recombinant human ace2 (race2) Search Results


96
Sino Biological hace2
(A) Schematics of the constructs of ACE2hR and ACE2iRb3 for generations of ACE2-overexpressing cell lines. EF1αp, human EF-1 alpha promoter; <t>hACE2,</t> human ACE2; IRES, internal ribosome entry site; H2BmRb3, H2B-fused mRuby3; BsR, blasticidin S-resistance gene; 2A, P2A peptide; ins, insulator; hCMVmie, a modified CMV promoter derived from pEE12.4 vector; hACE2-mRb3, <t>human</t> <t>ACE2</t> with C-terminal fusing of mRuby3; H2BiRFP, H2B-fused iRFP670; PuR, puromycin resistance gene. (B) Western blot analyses of expressions of ACE2 and TMPRSS2 in 293T and H1299 cells stably transfected with different constructs. NT cell, non-transfected cells. (C) Fluorescence confocal images of 293T-ACE2iRb3 cells incubated with SARS-CoV2-RBG and SARS-CoV2-STG for different times. The nucleus H2B-iRFP670 was pseudo-colored blue. The scale bar was 10 μm. (D) Schematic illustration of the procedures of cell-based high-content imaging assay using fluorescent RBG or STG viral entry sensors. (E) Dose-dependent fluorescence responses (cMFI) of various probes derived from different CoVs on 293T-ACE2iRb3 cells. SARS-CoV2-RBD488 was a dylight488-conjugated SARS-CoV2-RBD protein, and SARS-CoV2-ST488 was a dylight488-conjugated SARS-CoV2-ST protein. Each probe was tested at 500, 250, 125, 62.5, and 31.25 nM, respectively. (F) Comparisons of the fluorescence response (cMFI) of various SARS-CoV-2 probes on 293T-ACE2iRb3 cells. For panel E and F, cell images were obtained for 25 different views for each test, and the data were expressed as mean±SD. (G) Dose-dependent cMFI inhibition of recombinant ACE2, SARS-CoV2-RBD, and SARS-CoV2-S1 proteins for the binding and uptake of SARS-CoV2-STG (upper panel) and SARS-CoV2-RBG (lower panel). The experiments were performed following the procedure as described in panel D. The data were mean±SD. CSBT, cell-based spike function blocking test; CRBT, cell-based RBD function blocking test.
Hace2, supplied by Sino Biological, used in various techniques. Bioz Stars score: 96/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/bio_rxiv__2020__07__22__215236-228-11-16?v=Sino+Biological
Average 96 stars, based on 1 article reviews
hace2 - by Bioz Stars, 2026-07
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90
GeneTex recombinant human ace2 (race2)
Significant increase of CR Abs IgG in moderate/severe COVID-19 patients’ sera may contribute to cytokine secretion and NET formation in human leukocytes in the presence of RBD. IgG against nucleocapsid, N, RBD and <t>ACE2</t> proteins in sera from COVID-19 patients and healthy donors (HD) were measured by ELISA. Comparison of ( A ) the levels of IgG against N, ( B ) RBD, and ( C ) ACE2 in mild vs. moderate/severe COVID-19 patients. ( D ) Anti-ACE2 IgG levels in sera of mild vs. moderate/severe COVID-19 patients after BSA or RBD preadsorption. For the leukocyte activation test, isolated human leukocytes were preincubated with 1:100 diluted HD serum or sera from CR Ab-positive COVID-19 patients (CR serum) as indicated in the presence or absence of additional <t>rACE2</t> (10 μg/mL) for 30 min. Afterward, unbound antibodies were removed by centrifugation, and the cells were treated with the RBD protein (10 μg/mL) for 24 h. The supernatants were collected to measure the ( E ) TNF-α, ( F ) IL-1β, ( G ) IL-6, ( H ) IL-8, and ( I ) MPO levels using ELISA kits. The averages of triplicate cultures ± SD are shown. Multiple comparison of antibody response and leukocyte activation tests ( n = 3–5) was conducted by one-way ANOVA and Tukey’s post hoc test. The comparison between BSA and RBD preadsorption was analyzed by paired Student’s t-test; P values were displayed, and for values less than 0.0001, they were represented as ****
Recombinant Human Ace2 (Race2), supplied by GeneTex, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc11027296-50-0-7?v=GeneTex
Average 90 stars, based on 1 article reviews
recombinant human ace2 (race2) - by Bioz Stars, 2026-07
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95
R&D Systems recombinant ace2 race2
Effect of recombinant mouse <t>ACE2</t> (740) on systolic blood pressure increases induced by Ang II and Ang-(1-12) injection. The effect of recombinant mouse ACE2 (1 μg/g BW) on systolic blood pressure (SBP) responses caused by the injection of Ang II (left panel), Ang-(1-12) (middle panel) (both 0.2 μg/g BW, arrow), and Ang II and Ang-(1-12) superimposed over each other. ( Left ): Compared to a PBS pre-injected control group, <t>rACE2</t> reduced the SBP response to Ang II over ten minutes after injection by p = 0.0248 (rACE2) by 2-way ANOVA. When comparing over fifteen minutes, the injection of rACE2 reduced the SBP response by p = 0.058 (N = 4 vs. N = 4). ( Middle ): As compared to a PBS pre-injected control group, rACE2 did not reduce the SBP response to Ang-(1-12) either over ten minutes after injection ( p = 0.5461) or over fifteen minutes after injection ( p = 0.6610) (N = 5 vs. N = 3). ( Right ): Direct comparison of the effect of rACE2 on reducing the SBP response between the Ang II-induced (blue) and Ang-(1-12) (red)-induced SBP increase which was significantly different both over ten minutes from the injection ( p = 0.0176) and over fifteen minutes from the injection of the peptides ( p = 0.0230) (N = 4 vs. N = 5).
Recombinant Ace2 Race2, supplied by R&D Systems, used in various techniques. Bioz Stars score: 95/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc12296148-117-1-4?v=R%26D+Systems
Average 95 stars, based on 1 article reviews
recombinant ace2 race2 - by Bioz Stars, 2026-07
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92
R&D Systems recombinant mouse ace2
<t> ACE2 </t> substrate/assay buffer solution a
Recombinant Mouse Ace2, supplied by R&D Systems, used in various techniques. Bioz Stars score: 92/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc07121061-55-17-22?v=R%26D+Systems
Average 92 stars, based on 1 article reviews
recombinant mouse ace2 - by Bioz Stars, 2026-07
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95
R&D Systems recombinant human ace2
<t> ACE2 </t> substrate/assay buffer solution a
Recombinant Human Ace2, supplied by R&D Systems, used in various techniques. Bioz Stars score: 95/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc07121061-55-2-7?v=R%26D+Systems
Average 95 stars, based on 1 article reviews
recombinant human ace2 - by Bioz Stars, 2026-07
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90
APEIRON Biologics soluble human recombinant ace2 race2
SARS-CoV-2 infection in male and female k18-hace2 mice over 7 days post-infection (dpi) (A) Body weight loss in response to intranasal inoculation of SARS-CoV-2 (4 × 10 5 TCID50/50μL/mouse). ∗p < 0.05 vs. male. Data represented in median ± IQR. (B) Lung injury scoring assessed on a scale of 0–4 for each of the following criteria: 1) neutrophil numbers in the alveolar space, 2) alveolar septal thickening, 3) number of hyaline membranes, 4) alveolar hemorrhage, and 5) cellular hyperplasia. ∗p < 0.05 vs. Ctrl and male. Data represented in mean ± SEM. (C) Viral RNA levels in oropharyngeal swabs at 2, 4, and 6 dpi. ∗p < 0.05 vs. male. Data represented in median ± IQR. (D–G) Copy numbers of E-gene and RdRp-gene in multiple organ tissues. ∗p < 0.05 vs. Ctrl. Data represented in mean ± SEM. (H) Detection of SARS-CoV-2 nucleocapsid protein (red) in lung tissues. Scale bars, 50 μm (main images) and 20 μm (magnified). (I) Protein expression in lung tissue detected by western blots in vehicle control (C) and at 7 dpi. (J) Concentration of soluble RAGE protein in plasma in vehicle control and at 7 dpi. ∗p < 0.05 vs. other groups. Data represented in mean ± SEM. (K) Correlation of protein levels of <t>ACE2</t> and ERα in lung tissue of male mice before and after infection at 7 dpi. (L) Estrogen receptor alpha (ERα)/androgen receptor (AR) ratio assessed from western blot analysis in relation to β-actin loading control. ∗p < 0.05 vs. male. Data represented in mean ± SEM. (M) Concentration of 17β Estradiol in lung tissue homogenates in vehicle control and at 7 dpi. ∗p < 0.05 vs. male. n = 5–7 biologically independent mice for all groups. Data represented in mean ± SEM. (see also <xref ref-type=Figure S1 ). " width="250" height="auto" />
Soluble Human Recombinant Ace2 Race2, supplied by APEIRON Biologics, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc10440513-276-7-12?v=APEIRON+Biologics
Average 90 stars, based on 1 article reviews
soluble human recombinant ace2 race2 - by Bioz Stars, 2026-07
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90
Bachem disulfide bridged cyclic variant of dx600
Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or <t>DX600</t> (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)
Disulfide Bridged Cyclic Variant Of Dx600, supplied by Bachem, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc07121061-131-13-14?v=Bachem
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disulfide bridged cyclic variant of dx600 - by Bioz Stars, 2026-07
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90
Millennium Pharmaceuticals ace2 inhibitor mln-4760
Composition and function of the renin-angiotensin system and its main regulators and inhibitors. RAS: Rennin angiotensin system; ACEI: Angiotensin-converting enzyme inhibitor; ARB: Angiotensin II receptor blocker; ACE: Angiotensin-converting enzyme; <t>ACE2:</t> Angiotensin-converting enzyme 2; AT1R: Angiotensin type 1 receptor; AT2R: Angiotensin type 2 receptor; MasR: Mas receptor; MLN-4760: A specific ACE2 inhibitor; Organ damage: Renal damage, lung damage, cardiovascular damage, etc.
Ace2 Inhibitor Mln 4760, supplied by Millennium Pharmaceuticals, used in various techniques. Bioz Stars score: 90/100, based on 1 PubMed citations. ZERO BIAS - scores, article reviews, protocol conditions and more
https://www.bioz.com/product/recombinant+human+ace2+%28race2%29/pmc08192247-168-16-26?v=Millennium+Pharmaceuticals
Average 90 stars, based on 1 article reviews
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Image Search Results


(A) Schematics of the constructs of ACE2hR and ACE2iRb3 for generations of ACE2-overexpressing cell lines. EF1αp, human EF-1 alpha promoter; hACE2, human ACE2; IRES, internal ribosome entry site; H2BmRb3, H2B-fused mRuby3; BsR, blasticidin S-resistance gene; 2A, P2A peptide; ins, insulator; hCMVmie, a modified CMV promoter derived from pEE12.4 vector; hACE2-mRb3, human ACE2 with C-terminal fusing of mRuby3; H2BiRFP, H2B-fused iRFP670; PuR, puromycin resistance gene. (B) Western blot analyses of expressions of ACE2 and TMPRSS2 in 293T and H1299 cells stably transfected with different constructs. NT cell, non-transfected cells. (C) Fluorescence confocal images of 293T-ACE2iRb3 cells incubated with SARS-CoV2-RBG and SARS-CoV2-STG for different times. The nucleus H2B-iRFP670 was pseudo-colored blue. The scale bar was 10 μm. (D) Schematic illustration of the procedures of cell-based high-content imaging assay using fluorescent RBG or STG viral entry sensors. (E) Dose-dependent fluorescence responses (cMFI) of various probes derived from different CoVs on 293T-ACE2iRb3 cells. SARS-CoV2-RBD488 was a dylight488-conjugated SARS-CoV2-RBD protein, and SARS-CoV2-ST488 was a dylight488-conjugated SARS-CoV2-ST protein. Each probe was tested at 500, 250, 125, 62.5, and 31.25 nM, respectively. (F) Comparisons of the fluorescence response (cMFI) of various SARS-CoV-2 probes on 293T-ACE2iRb3 cells. For panel E and F, cell images were obtained for 25 different views for each test, and the data were expressed as mean±SD. (G) Dose-dependent cMFI inhibition of recombinant ACE2, SARS-CoV2-RBD, and SARS-CoV2-S1 proteins for the binding and uptake of SARS-CoV2-STG (upper panel) and SARS-CoV2-RBG (lower panel). The experiments were performed following the procedure as described in panel D. The data were mean±SD. CSBT, cell-based spike function blocking test; CRBT, cell-based RBD function blocking test.

Journal: bioRxiv

Article Title: Virus-free and live-cell visualizing SARS-CoV-2 cell entry for studies of neutralizing antibodies and compound inhibitors

doi: 10.1101/2020.07.22.215236

Figure Lengend Snippet: (A) Schematics of the constructs of ACE2hR and ACE2iRb3 for generations of ACE2-overexpressing cell lines. EF1αp, human EF-1 alpha promoter; hACE2, human ACE2; IRES, internal ribosome entry site; H2BmRb3, H2B-fused mRuby3; BsR, blasticidin S-resistance gene; 2A, P2A peptide; ins, insulator; hCMVmie, a modified CMV promoter derived from pEE12.4 vector; hACE2-mRb3, human ACE2 with C-terminal fusing of mRuby3; H2BiRFP, H2B-fused iRFP670; PuR, puromycin resistance gene. (B) Western blot analyses of expressions of ACE2 and TMPRSS2 in 293T and H1299 cells stably transfected with different constructs. NT cell, non-transfected cells. (C) Fluorescence confocal images of 293T-ACE2iRb3 cells incubated with SARS-CoV2-RBG and SARS-CoV2-STG for different times. The nucleus H2B-iRFP670 was pseudo-colored blue. The scale bar was 10 μm. (D) Schematic illustration of the procedures of cell-based high-content imaging assay using fluorescent RBG or STG viral entry sensors. (E) Dose-dependent fluorescence responses (cMFI) of various probes derived from different CoVs on 293T-ACE2iRb3 cells. SARS-CoV2-RBD488 was a dylight488-conjugated SARS-CoV2-RBD protein, and SARS-CoV2-ST488 was a dylight488-conjugated SARS-CoV2-ST protein. Each probe was tested at 500, 250, 125, 62.5, and 31.25 nM, respectively. (F) Comparisons of the fluorescence response (cMFI) of various SARS-CoV-2 probes on 293T-ACE2iRb3 cells. For panel E and F, cell images were obtained for 25 different views for each test, and the data were expressed as mean±SD. (G) Dose-dependent cMFI inhibition of recombinant ACE2, SARS-CoV2-RBD, and SARS-CoV2-S1 proteins for the binding and uptake of SARS-CoV2-STG (upper panel) and SARS-CoV2-RBG (lower panel). The experiments were performed following the procedure as described in panel D. The data were mean±SD. CSBT, cell-based spike function blocking test; CRBT, cell-based RBD function blocking test.

Article Snippet: For determinations of the binding affinities of SARS-CoV2-RBG and SARS-CoV2-STG to hACE2 , rACE2 (mouse-Fc tagged, Sino Biological) proteins were immobilized to a protein A sensorchip a level of ~500 response units (RUs) using Biacore 8000 (GE Healthcare) and a running buffer of composed of 20mM PB7.4 with 300 mM NaCl.

Techniques: Construct, Modification, Derivative Assay, Plasmid Preparation, Western Blot, Stable Transfection, Transfection, Fluorescence, Incubation, Imaging, Inhibition, Recombinant, Binding Assay, Blocking Assay

Significant increase of CR Abs IgG in moderate/severe COVID-19 patients’ sera may contribute to cytokine secretion and NET formation in human leukocytes in the presence of RBD. IgG against nucleocapsid, N, RBD and ACE2 proteins in sera from COVID-19 patients and healthy donors (HD) were measured by ELISA. Comparison of ( A ) the levels of IgG against N, ( B ) RBD, and ( C ) ACE2 in mild vs. moderate/severe COVID-19 patients. ( D ) Anti-ACE2 IgG levels in sera of mild vs. moderate/severe COVID-19 patients after BSA or RBD preadsorption. For the leukocyte activation test, isolated human leukocytes were preincubated with 1:100 diluted HD serum or sera from CR Ab-positive COVID-19 patients (CR serum) as indicated in the presence or absence of additional rACE2 (10 μg/mL) for 30 min. Afterward, unbound antibodies were removed by centrifugation, and the cells were treated with the RBD protein (10 μg/mL) for 24 h. The supernatants were collected to measure the ( E ) TNF-α, ( F ) IL-1β, ( G ) IL-6, ( H ) IL-8, and ( I ) MPO levels using ELISA kits. The averages of triplicate cultures ± SD are shown. Multiple comparison of antibody response and leukocyte activation tests ( n = 3–5) was conducted by one-way ANOVA and Tukey’s post hoc test. The comparison between BSA and RBD preadsorption was analyzed by paired Student’s t-test; P values were displayed, and for values less than 0.0001, they were represented as ****

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: Significant increase of CR Abs IgG in moderate/severe COVID-19 patients’ sera may contribute to cytokine secretion and NET formation in human leukocytes in the presence of RBD. IgG against nucleocapsid, N, RBD and ACE2 proteins in sera from COVID-19 patients and healthy donors (HD) were measured by ELISA. Comparison of ( A ) the levels of IgG against N, ( B ) RBD, and ( C ) ACE2 in mild vs. moderate/severe COVID-19 patients. ( D ) Anti-ACE2 IgG levels in sera of mild vs. moderate/severe COVID-19 patients after BSA or RBD preadsorption. For the leukocyte activation test, isolated human leukocytes were preincubated with 1:100 diluted HD serum or sera from CR Ab-positive COVID-19 patients (CR serum) as indicated in the presence or absence of additional rACE2 (10 μg/mL) for 30 min. Afterward, unbound antibodies were removed by centrifugation, and the cells were treated with the RBD protein (10 μg/mL) for 24 h. The supernatants were collected to measure the ( E ) TNF-α, ( F ) IL-1β, ( G ) IL-6, ( H ) IL-8, and ( I ) MPO levels using ELISA kits. The averages of triplicate cultures ± SD are shown. Multiple comparison of antibody response and leukocyte activation tests ( n = 3–5) was conducted by one-way ANOVA and Tukey’s post hoc test. The comparison between BSA and RBD preadsorption was analyzed by paired Student’s t-test; P values were displayed, and for values less than 0.0001, they were represented as ****

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Enzyme-linked Immunosorbent Assay, Comparison, Activation Assay, Isolation, Centrifugation

CR Abs induce human neutrophils to secrete IL-8 and MPO in the presence of RBD. ( A , B ) Isolated human neutrophils (2 × 10 6 cells/mL, 0.3 mL/test) were treated with the recombinant RBD protein in the presence or absence of the indicated antibodies (mAb 127 or cmIgG) for different time points (1, 3, 6, and 24 h). ( C , D ) Neutrophils were cotreated with 10 μg/mL RBD recombinant protein and mAb 127 or cmIgG at different concentrations (2.5, 5, or 10 μg/mL). ( E , F ) Neutrophils were stimulated with the recombinant RBD protein in the presence or absence of the indicated antibodies (mAbs 127, LGSV201, cmIgG, or anti-ACE2) for 24 h. The supernatants from these experiments were collected, and IL-8 and MPO levels were quantified using ELISA kits. The averages of triplicate cultures ± SD are shown. Statistical significance was calculated using one-way ANOVA and Tukey’s post hoc test; P values were displayed, and for values less than 0.0001, they were represented as ****

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: CR Abs induce human neutrophils to secrete IL-8 and MPO in the presence of RBD. ( A , B ) Isolated human neutrophils (2 × 10 6 cells/mL, 0.3 mL/test) were treated with the recombinant RBD protein in the presence or absence of the indicated antibodies (mAb 127 or cmIgG) for different time points (1, 3, 6, and 24 h). ( C , D ) Neutrophils were cotreated with 10 μg/mL RBD recombinant protein and mAb 127 or cmIgG at different concentrations (2.5, 5, or 10 μg/mL). ( E , F ) Neutrophils were stimulated with the recombinant RBD protein in the presence or absence of the indicated antibodies (mAbs 127, LGSV201, cmIgG, or anti-ACE2) for 24 h. The supernatants from these experiments were collected, and IL-8 and MPO levels were quantified using ELISA kits. The averages of triplicate cultures ± SD are shown. Statistical significance was calculated using one-way ANOVA and Tukey’s post hoc test; P values were displayed, and for values less than 0.0001, they were represented as ****

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Isolation, Recombinant, Enzyme-linked Immunosorbent Assay

NETosis triggered by CR Abs in the presence of RBD drives thrombosis-associated cell activation. ( A ) Isolated human neutrophils were treated with 10 μg/mL recombinant RBD protein and the indicated antibodies (mAbs 127, LGSV201, or cmIgG, 10 μg/mL) or not. After the indicated time points, the cell suspensions were spun onto a microscope slide by using a cytocentrifuge, fixed and stained with anti-CD66b antibody (green), anti-MPO antibody (red) and DAPI (blue) nuclear stain and then visualized using immunofluorescence staining. The area of NET formation at ( B ) different time points or ( C ) 24 h after stimulation was quantified by ImageJ. Views for NET quantification were randomly selected with 9 pictures from each experiment. The supernatants of neutrophils were harvested after different treatments and further administered to isolated human PBMCs, HUVECs, or platelets. Purified PMA-induced NETs (1 μg/mL) were used as the positive control, and in some experiments, rACE2 was added. Following 24 h of stimulation with neutrophil-conditioned media, PBMC supernatants were collected to measure the ( D ) TNF-α and ( E ) IL-6 levels using ELISA kits. ( F ) Endothelial barrier integrity was determined by a Transwell permeability assay, as described in the Materials and Methods. ( G ) After 15 min of stimulation, the percent fluorescence of P-selectin surface expression on platelets was measured by anti-CD62p FITC-conjugated antibodies and further analyzed by cytoFLEX. The averages of triplicate cultures ± SD are shown. Statistical significance was calculated using one-way ANOVA and Tukey’s post hoc test, **** p < 0.0001. Bar: 25 μm

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: NETosis triggered by CR Abs in the presence of RBD drives thrombosis-associated cell activation. ( A ) Isolated human neutrophils were treated with 10 μg/mL recombinant RBD protein and the indicated antibodies (mAbs 127, LGSV201, or cmIgG, 10 μg/mL) or not. After the indicated time points, the cell suspensions were spun onto a microscope slide by using a cytocentrifuge, fixed and stained with anti-CD66b antibody (green), anti-MPO antibody (red) and DAPI (blue) nuclear stain and then visualized using immunofluorescence staining. The area of NET formation at ( B ) different time points or ( C ) 24 h after stimulation was quantified by ImageJ. Views for NET quantification were randomly selected with 9 pictures from each experiment. The supernatants of neutrophils were harvested after different treatments and further administered to isolated human PBMCs, HUVECs, or platelets. Purified PMA-induced NETs (1 μg/mL) were used as the positive control, and in some experiments, rACE2 was added. Following 24 h of stimulation with neutrophil-conditioned media, PBMC supernatants were collected to measure the ( D ) TNF-α and ( E ) IL-6 levels using ELISA kits. ( F ) Endothelial barrier integrity was determined by a Transwell permeability assay, as described in the Materials and Methods. ( G ) After 15 min of stimulation, the percent fluorescence of P-selectin surface expression on platelets was measured by anti-CD62p FITC-conjugated antibodies and further analyzed by cytoFLEX. The averages of triplicate cultures ± SD are shown. Statistical significance was calculated using one-way ANOVA and Tukey’s post hoc test, **** p < 0.0001. Bar: 25 μm

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Activation Assay, Isolation, Recombinant, Microscopy, Staining, Immunofluorescence, Purification, Positive Control, Enzyme-linked Immunosorbent Assay, Permeability, Fluorescence, Expressing

CR Abs-triggered NETosis is dependent on ACE2 and the Fc receptor. Isolated human neutrophils were treated with recombinant RBD protein (10 μg/mL) and the indicated antibodies (mAb 127, mAb 127-F(ab’) 2 , or cmIgG-F(ab’) 2 , 10 μg/mL) in the presence or absence of additional rACE2 (1 or 10 μg/mL) for 24 h. The supernatants were collected to measure the levels of ( A , E ) IL-8 and ( B , F ) MPO using ELISA kits. ( C , D , G , H ) The cell suspensions were spun onto a microscope slide by using a cytocentrifuge and were fixed and subjected to immunofluorescence staining with an anti-MPO antibody (green), anti-histone antibody (red) and Hoechst (blue) nuclear stain, and the area of NET formation was quantified by ImageJ. The averages of triplicate cultures ± SD are shown. The views for NET quantification were randomly selected with 9 pictures from each experiment. Statistical significance was calculated using one-way ANOVA and Tukey’s post hoc test; P values were displayed, and for values less than 0.0001, they were represented as ****. Bar: 25 μm

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: CR Abs-triggered NETosis is dependent on ACE2 and the Fc receptor. Isolated human neutrophils were treated with recombinant RBD protein (10 μg/mL) and the indicated antibodies (mAb 127, mAb 127-F(ab’) 2 , or cmIgG-F(ab’) 2 , 10 μg/mL) in the presence or absence of additional rACE2 (1 or 10 μg/mL) for 24 h. The supernatants were collected to measure the levels of ( A , E ) IL-8 and ( B , F ) MPO using ELISA kits. ( C , D , G , H ) The cell suspensions were spun onto a microscope slide by using a cytocentrifuge and were fixed and subjected to immunofluorescence staining with an anti-MPO antibody (green), anti-histone antibody (red) and Hoechst (blue) nuclear stain, and the area of NET formation was quantified by ImageJ. The averages of triplicate cultures ± SD are shown. The views for NET quantification were randomly selected with 9 pictures from each experiment. Statistical significance was calculated using one-way ANOVA and Tukey’s post hoc test; P values were displayed, and for values less than 0.0001, they were represented as ****. Bar: 25 μm

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Isolation, Recombinant, Enzyme-linked Immunosorbent Assay, Microscopy, Immunofluorescence, Staining

CR IgG purified from unvaccinated COVID-19 patients induces neutrophil activation and NETosis in the presence of RBD. Isolated human neutrophils were preincubated with 100 μg/mL purified IgG from HD serum (HD IgG) or different COVID-19 patient sera: anti-RBD IgG (anti-ACE2 antibody negative but anti-RBD antibody positive), anti-ACE2 IgG (anti-ACE2 antibody positive), or CR IgG (CR antibody positive) in the presence or absence of additional rACE2 (10 μg/mL) or dasatinib (50 nM) as indicated for 30 min. After removing unbound antibodies by centrifugation, cells were treated with the RBD protein (10 μg/mL) for 24 h. ( A ) IL-8 and ( B ) MPO levels in the supernatants were measured using ELISA kits. ( C , D ) Cell suspensions were cytocentrifuged onto microscope slides, fixed, and subjected to immunofluorescence staining with anti-MPO antibody (green), anti-histone antibody (red), and Hoechst nuclear stain (blue). The red arrow indicates neutrophils that released NETs. The area of NET formation was quantified using ImageJ. Averages of triplicate cultures ± SD are shown. Views for NET quantification were randomly selected with 9 pictures from each experiment. Statistical significance was assessed using one-way ANOVA and Tukey’s post hoc test; **** p < 0.0001. Bar: 25 μm

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: CR IgG purified from unvaccinated COVID-19 patients induces neutrophil activation and NETosis in the presence of RBD. Isolated human neutrophils were preincubated with 100 μg/mL purified IgG from HD serum (HD IgG) or different COVID-19 patient sera: anti-RBD IgG (anti-ACE2 antibody negative but anti-RBD antibody positive), anti-ACE2 IgG (anti-ACE2 antibody positive), or CR IgG (CR antibody positive) in the presence or absence of additional rACE2 (10 μg/mL) or dasatinib (50 nM) as indicated for 30 min. After removing unbound antibodies by centrifugation, cells were treated with the RBD protein (10 μg/mL) for 24 h. ( A ) IL-8 and ( B ) MPO levels in the supernatants were measured using ELISA kits. ( C , D ) Cell suspensions were cytocentrifuged onto microscope slides, fixed, and subjected to immunofluorescence staining with anti-MPO antibody (green), anti-histone antibody (red), and Hoechst nuclear stain (blue). The red arrow indicates neutrophils that released NETs. The area of NET formation was quantified using ImageJ. Averages of triplicate cultures ± SD are shown. Views for NET quantification were randomly selected with 9 pictures from each experiment. Statistical significance was assessed using one-way ANOVA and Tukey’s post hoc test; **** p < 0.0001. Bar: 25 μm

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Purification, Activation Assay, Isolation, Centrifugation, Enzyme-linked Immunosorbent Assay, Microscopy, Immunofluorescence, Staining

Distribution of disease severity,  anti-ACE2  autoantibody and CR antibody positive rate in COVID-19 patients with vaccination (Vac) or without (UnVac)

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: Distribution of disease severity, anti-ACE2 autoantibody and CR antibody positive rate in COVID-19 patients with vaccination (Vac) or without (UnVac)

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques:

Vaccination is conducive to decreasing CR Abs IgG levels in the sera of COVID-19 patients. IgG against ( A ) RBD, ( B ) nucleocapsid, N and ( C ) ACE2 proteins in sera from different groups were measured by ELISA. ( D ) Anti-ACE2 IgG levels in sera of unvaccinated COVID-19 patients and vaccinated COVID-19 patients after BSA or RBD preadsorption. Multiple comparisons in COVID-19 samples were conducted by two-way ANOVA. The comparison between BSA and RBD preadsorption was analyzed by paired Student’s t-test; P values were displayed, and for values less than 0.0001, they were represented as ****

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: Vaccination is conducive to decreasing CR Abs IgG levels in the sera of COVID-19 patients. IgG against ( A ) RBD, ( B ) nucleocapsid, N and ( C ) ACE2 proteins in sera from different groups were measured by ELISA. ( D ) Anti-ACE2 IgG levels in sera of unvaccinated COVID-19 patients and vaccinated COVID-19 patients after BSA or RBD preadsorption. Multiple comparisons in COVID-19 samples were conducted by two-way ANOVA. The comparison between BSA and RBD preadsorption was analyzed by paired Student’s t-test; P values were displayed, and for values less than 0.0001, they were represented as ****

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Enzyme-linked Immunosorbent Assay, Comparison

The potential mechanisms underlying CR Ab-induced thrombosis. (1) CR Abs binding to RBD and ACE2 as well as Fc receptors on the surface of neutrophils induce signaling pathways. (2) Signaling pathways that regulate IL-8 secretion and NET formation are activated: SFK-AMPK signaling mediates IL-8 secretion, while SFK-PI3K-PAD4 signaling mediates NET formation. The actions of both IL-8 and NETs could be suppressed by dasatinib, which is an SFK inhibitor. (3) Secreted IL-8 and NETs subsequently cause (4) the secretion of TNFα, IL-6, and IL-1β from PBMCs, (5) enhanced expression of surface P-selectin on platelets, and (6) increased endothelial permeability. These processes collectively contribute to the eventual formation of thrombi. CR Ab, ACE2-cross-reactive RBD antibodies; ACE2, angiotensin converting enzyme-2; RBD, SARS-CoV-2 receptor binding domain; IL-8, interleukin-8; NETs, neutrophil extracellular traps; SFK, Src family kinases; AMPK, AMP-activated protein kinase; PI3K, phosphoinositide 3-kinase; PAD4, protein arginine deiminase 4; TNFα, tumor necrosis factor alpha; IL-6, interleukin-6; IL-1β, interleukin-1β; PBMC, peripheral blood mononuclear cells. Created with BioRender.com

Journal: Journal of Biomedical Science

Article Title: Enhancement of NETosis by ACE2-cross-reactive anti-SARS-CoV-2 RBD antibodies in patients with COVID-19

doi: 10.1186/s12929-024-01026-5

Figure Lengend Snippet: The potential mechanisms underlying CR Ab-induced thrombosis. (1) CR Abs binding to RBD and ACE2 as well as Fc receptors on the surface of neutrophils induce signaling pathways. (2) Signaling pathways that regulate IL-8 secretion and NET formation are activated: SFK-AMPK signaling mediates IL-8 secretion, while SFK-PI3K-PAD4 signaling mediates NET formation. The actions of both IL-8 and NETs could be suppressed by dasatinib, which is an SFK inhibitor. (3) Secreted IL-8 and NETs subsequently cause (4) the secretion of TNFα, IL-6, and IL-1β from PBMCs, (5) enhanced expression of surface P-selectin on platelets, and (6) increased endothelial permeability. These processes collectively contribute to the eventual formation of thrombi. CR Ab, ACE2-cross-reactive RBD antibodies; ACE2, angiotensin converting enzyme-2; RBD, SARS-CoV-2 receptor binding domain; IL-8, interleukin-8; NETs, neutrophil extracellular traps; SFK, Src family kinases; AMPK, AMP-activated protein kinase; PI3K, phosphoinositide 3-kinase; PAD4, protein arginine deiminase 4; TNFα, tumor necrosis factor alpha; IL-6, interleukin-6; IL-1β, interleukin-1β; PBMC, peripheral blood mononuclear cells. Created with BioRender.com

Article Snippet: Recombinant human ACE2 (rACE2) was purchased from Genetex (Irvine, CA).

Techniques: Binding Assay, Protein-Protein interactions, Expressing, Permeability

Effect of recombinant mouse ACE2 (740) on systolic blood pressure increases induced by Ang II and Ang-(1-12) injection. The effect of recombinant mouse ACE2 (1 μg/g BW) on systolic blood pressure (SBP) responses caused by the injection of Ang II (left panel), Ang-(1-12) (middle panel) (both 0.2 μg/g BW, arrow), and Ang II and Ang-(1-12) superimposed over each other. ( Left ): Compared to a PBS pre-injected control group, rACE2 reduced the SBP response to Ang II over ten minutes after injection by p = 0.0248 (rACE2) by 2-way ANOVA. When comparing over fifteen minutes, the injection of rACE2 reduced the SBP response by p = 0.058 (N = 4 vs. N = 4). ( Middle ): As compared to a PBS pre-injected control group, rACE2 did not reduce the SBP response to Ang-(1-12) either over ten minutes after injection ( p = 0.5461) or over fifteen minutes after injection ( p = 0.6610) (N = 5 vs. N = 3). ( Right ): Direct comparison of the effect of rACE2 on reducing the SBP response between the Ang II-induced (blue) and Ang-(1-12) (red)-induced SBP increase which was significantly different both over ten minutes from the injection ( p = 0.0176) and over fifteen minutes from the injection of the peptides ( p = 0.0230) (N = 4 vs. N = 5).

Journal: International Journal of Molecular Sciences

Article Title: Aminopeptidase A Effect on Angiotensin Peptides and Their Blood Pressure Action

doi: 10.3390/ijms26146990

Figure Lengend Snippet: Effect of recombinant mouse ACE2 (740) on systolic blood pressure increases induced by Ang II and Ang-(1-12) injection. The effect of recombinant mouse ACE2 (1 μg/g BW) on systolic blood pressure (SBP) responses caused by the injection of Ang II (left panel), Ang-(1-12) (middle panel) (both 0.2 μg/g BW, arrow), and Ang II and Ang-(1-12) superimposed over each other. ( Left ): Compared to a PBS pre-injected control group, rACE2 reduced the SBP response to Ang II over ten minutes after injection by p = 0.0248 (rACE2) by 2-way ANOVA. When comparing over fifteen minutes, the injection of rACE2 reduced the SBP response by p = 0.058 (N = 4 vs. N = 4). ( Middle ): As compared to a PBS pre-injected control group, rACE2 did not reduce the SBP response to Ang-(1-12) either over ten minutes after injection ( p = 0.5461) or over fifteen minutes after injection ( p = 0.6610) (N = 5 vs. N = 3). ( Right ): Direct comparison of the effect of rACE2 on reducing the SBP response between the Ang II-induced (blue) and Ang-(1-12) (red)-induced SBP increase which was significantly different both over ten minutes from the injection ( p = 0.0176) and over fifteen minutes from the injection of the peptides ( p = 0.0230) (N = 4 vs. N = 5).

Article Snippet: Moreover, recombinant ACE2 (rACE2) (R&D Systems, 100 fmol), a mono-carboxypeptidase enzyme that does not cleave N-terminal aspartate but cleaves C-terminal basic and hydrophobic amino acids [ ], was used as another negative control to show that, when incubated with Ang peptides bearing N-terminal aspartate, no fluorescent signal can be produced.

Techniques: Recombinant, Injection, Control, Comparison

 ACE2  substrate/assay buffer solution a

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: ACE2 substrate/assay buffer solution a

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques:

Components of  ACE2  activity standard curve solution (per well) a

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Components of ACE2 activity standard curve solution (per well) a

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay

Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or DX600 (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or DX600 (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Recombinant, Generated

Intra- and inter-assay coefficients of variability (CV)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Intra- and inter-assay coefficients of variability (CV)

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Inter Assay, Activity Assay, Intra Assay, Clinical Proteomics

Effect of ACE2 inhibitors MLN-4760 (10 −6 M), DX600 (10 −6 M), and ACE inhibitor captopril (10 −5 M) on ACE2 enzyme activity. The assay was performed for 16 h incubation. Graph depicts the concentrations of recombinant ACE2 versus the Relative Fluorescence Units (RFU). A background RFU value (67.5 RFU for a , 62.0 RFU for b ) of the substrate blank control was subtracted from the readings for each well. ( a ) Effect of MLN-4760, DX600, and captopril on human rACE2 activity. ( b ) Effect of MLN-4760, DX600, and captopril on mouse rACE2 activity

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of ACE2 inhibitors MLN-4760 (10 −6 M), DX600 (10 −6 M), and ACE inhibitor captopril (10 −5 M) on ACE2 enzyme activity. The assay was performed for 16 h incubation. Graph depicts the concentrations of recombinant ACE2 versus the Relative Fluorescence Units (RFU). A background RFU value (67.5 RFU for a , 62.0 RFU for b ) of the substrate blank control was subtracted from the readings for each well. ( a ) Effect of MLN-4760, DX600, and captopril on human rACE2 activity. ( b ) Effect of MLN-4760, DX600, and captopril on mouse rACE2 activity

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Recombinant, Fluorescence, Control

Effect of substrate concentrations on ACE2 activity. ( a ) The assay was performed with different ACE2 substrate concentrations (11.25, 5.63, 2.81, and 1.41 μM) for 16 h incubation using mouse rACE2 concentrations between 0 and 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the activity (RFU) at different substrate concentrations. ( b ) Standard curves generated for mouse rACE2 with 11.25 or 5.63 μM ACE2 substrate concentrations. A highly linear relationship between mouse rACE2 and the RFU exists for both substrate concentrations ( R 2 = 0.9994, p < 0.001 for 11.25 μM; R 2 = 0.9903, p < 0.001 for 5.63 μM)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of substrate concentrations on ACE2 activity. ( a ) The assay was performed with different ACE2 substrate concentrations (11.25, 5.63, 2.81, and 1.41 μM) for 16 h incubation using mouse rACE2 concentrations between 0 and 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the activity (RFU) at different substrate concentrations. ( b ) Standard curves generated for mouse rACE2 with 11.25 or 5.63 μM ACE2 substrate concentrations. A highly linear relationship between mouse rACE2 and the RFU exists for both substrate concentrations ( R 2 = 0.9994, p < 0.001 for 11.25 μM; R 2 = 0.9903, p < 0.001 for 5.63 μM)

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Generated

Time course of ACE2 activity assay. ACE2 activity was measured for 2, 6, 16, and 24 h incubation, with mouse rACE2 concentrations ranging from 0 to 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the ACE2 activity (RFU) at different time points. ( a ) Standard curve generated for mouse rACE2 for 2 h incubation. A highly linear relationship exists for rACE2 concentrations from 0 to 200 ng/ml ( R 2 = 0.9981, p < 0.001). The area marked with dashed lines is shown in b . ( b ) Standard curve generated for mouse rACE2 for 16 h incubation. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Time course of ACE2 activity assay. ACE2 activity was measured for 2, 6, 16, and 24 h incubation, with mouse rACE2 concentrations ranging from 0 to 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the ACE2 activity (RFU) at different time points. ( a ) Standard curve generated for mouse rACE2 for 2 h incubation. A highly linear relationship exists for rACE2 concentrations from 0 to 200 ng/ml ( R 2 = 0.9981, p < 0.001). The area marked with dashed lines is shown in b . ( b ) Standard curve generated for mouse rACE2 for 16 h incubation. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Generated

Effect of potential modulators on ACE2 activity assay. The assay was performed for 16 h incubation. ( a ) Graph shows ACE2 activity in defined medium (not incubated with mouse PT cells), and culture medium collected from primary cultures of mouse PT cells after 72 h incubation, in the presence of normal (7.8 mM) or high concentrations of d -glucose (HG, 25 mM). No ACE2 activity is detected in the defined medium. Results are means ± SEM; p > 0.05, culture medium vs culture medium + HG; n = 3. ( b ) Graph depicts the effect of addition of various concentrations of creatinine on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( c ) Graph depicts the effect of addition of various concentrations of urea on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( d ) Graph depicts the effect of addition of exogenous albumin on ACE2 activity (RFU) at different mouse rACE2 concentrations. Albumin at the indicated concentrations was added to urine samples (1 μl) from mice with gene deletion of ACE2. Results are means ± SEM; p > 0.05 for all graphs; n = 3

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of potential modulators on ACE2 activity assay. The assay was performed for 16 h incubation. ( a ) Graph shows ACE2 activity in defined medium (not incubated with mouse PT cells), and culture medium collected from primary cultures of mouse PT cells after 72 h incubation, in the presence of normal (7.8 mM) or high concentrations of d -glucose (HG, 25 mM). No ACE2 activity is detected in the defined medium. Results are means ± SEM; p > 0.05, culture medium vs culture medium + HG; n = 3. ( b ) Graph depicts the effect of addition of various concentrations of creatinine on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( c ) Graph depicts the effect of addition of various concentrations of urea on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( d ) Graph depicts the effect of addition of exogenous albumin on ACE2 activity (RFU) at different mouse rACE2 concentrations. Albumin at the indicated concentrations was added to urine samples (1 μl) from mice with gene deletion of ACE2. Results are means ± SEM; p > 0.05 for all graphs; n = 3

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation

 ACE2  substrate/assay buffer solution a

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: ACE2 substrate/assay buffer solution a

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques:

Components of  ACE2  activity standard curve solution (per well) a

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Components of ACE2 activity standard curve solution (per well) a

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay

Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or DX600 (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or DX600 (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Recombinant, Generated

Intra- and inter-assay coefficients of variability (CV)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Intra- and inter-assay coefficients of variability (CV)

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Inter Assay, Activity Assay, Intra Assay, Clinical Proteomics

Effect of ACE2 inhibitors MLN-4760 (10 −6 M), DX600 (10 −6 M), and ACE inhibitor captopril (10 −5 M) on ACE2 enzyme activity. The assay was performed for 16 h incubation. Graph depicts the concentrations of recombinant ACE2 versus the Relative Fluorescence Units (RFU). A background RFU value (67.5 RFU for a , 62.0 RFU for b ) of the substrate blank control was subtracted from the readings for each well. ( a ) Effect of MLN-4760, DX600, and captopril on human rACE2 activity. ( b ) Effect of MLN-4760, DX600, and captopril on mouse rACE2 activity

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of ACE2 inhibitors MLN-4760 (10 −6 M), DX600 (10 −6 M), and ACE inhibitor captopril (10 −5 M) on ACE2 enzyme activity. The assay was performed for 16 h incubation. Graph depicts the concentrations of recombinant ACE2 versus the Relative Fluorescence Units (RFU). A background RFU value (67.5 RFU for a , 62.0 RFU for b ) of the substrate blank control was subtracted from the readings for each well. ( a ) Effect of MLN-4760, DX600, and captopril on human rACE2 activity. ( b ) Effect of MLN-4760, DX600, and captopril on mouse rACE2 activity

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Recombinant, Fluorescence, Control

Effect of substrate concentrations on ACE2 activity. ( a ) The assay was performed with different ACE2 substrate concentrations (11.25, 5.63, 2.81, and 1.41 μM) for 16 h incubation using mouse rACE2 concentrations between 0 and 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the activity (RFU) at different substrate concentrations. ( b ) Standard curves generated for mouse rACE2 with 11.25 or 5.63 μM ACE2 substrate concentrations. A highly linear relationship between mouse rACE2 and the RFU exists for both substrate concentrations ( R 2 = 0.9994, p < 0.001 for 11.25 μM; R 2 = 0.9903, p < 0.001 for 5.63 μM)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of substrate concentrations on ACE2 activity. ( a ) The assay was performed with different ACE2 substrate concentrations (11.25, 5.63, 2.81, and 1.41 μM) for 16 h incubation using mouse rACE2 concentrations between 0 and 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the activity (RFU) at different substrate concentrations. ( b ) Standard curves generated for mouse rACE2 with 11.25 or 5.63 μM ACE2 substrate concentrations. A highly linear relationship between mouse rACE2 and the RFU exists for both substrate concentrations ( R 2 = 0.9994, p < 0.001 for 11.25 μM; R 2 = 0.9903, p < 0.001 for 5.63 μM)

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Generated

Time course of ACE2 activity assay. ACE2 activity was measured for 2, 6, 16, and 24 h incubation, with mouse rACE2 concentrations ranging from 0 to 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the ACE2 activity (RFU) at different time points. ( a ) Standard curve generated for mouse rACE2 for 2 h incubation. A highly linear relationship exists for rACE2 concentrations from 0 to 200 ng/ml ( R 2 = 0.9981, p < 0.001). The area marked with dashed lines is shown in b . ( b ) Standard curve generated for mouse rACE2 for 16 h incubation. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Time course of ACE2 activity assay. ACE2 activity was measured for 2, 6, 16, and 24 h incubation, with mouse rACE2 concentrations ranging from 0 to 200 ng/ml. Graph depicts the concentrations of mouse rACE2 versus the ACE2 activity (RFU) at different time points. ( a ) Standard curve generated for mouse rACE2 for 2 h incubation. A highly linear relationship exists for rACE2 concentrations from 0 to 200 ng/ml ( R 2 = 0.9981, p < 0.001). The area marked with dashed lines is shown in b . ( b ) Standard curve generated for mouse rACE2 for 16 h incubation. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation, Generated

Effect of potential modulators on ACE2 activity assay. The assay was performed for 16 h incubation. ( a ) Graph shows ACE2 activity in defined medium (not incubated with mouse PT cells), and culture medium collected from primary cultures of mouse PT cells after 72 h incubation, in the presence of normal (7.8 mM) or high concentrations of d -glucose (HG, 25 mM). No ACE2 activity is detected in the defined medium. Results are means ± SEM; p > 0.05, culture medium vs culture medium + HG; n = 3. ( b ) Graph depicts the effect of addition of various concentrations of creatinine on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( c ) Graph depicts the effect of addition of various concentrations of urea on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( d ) Graph depicts the effect of addition of exogenous albumin on ACE2 activity (RFU) at different mouse rACE2 concentrations. Albumin at the indicated concentrations was added to urine samples (1 μl) from mice with gene deletion of ACE2. Results are means ± SEM; p > 0.05 for all graphs; n = 3

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of potential modulators on ACE2 activity assay. The assay was performed for 16 h incubation. ( a ) Graph shows ACE2 activity in defined medium (not incubated with mouse PT cells), and culture medium collected from primary cultures of mouse PT cells after 72 h incubation, in the presence of normal (7.8 mM) or high concentrations of d -glucose (HG, 25 mM). No ACE2 activity is detected in the defined medium. Results are means ± SEM; p > 0.05, culture medium vs culture medium + HG; n = 3. ( b ) Graph depicts the effect of addition of various concentrations of creatinine on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( c ) Graph depicts the effect of addition of various concentrations of urea on ACE2 activity (RFU) at different mouse rACE2 concentrations. Results are means ± SEM; p > 0.05 for all graphs; n = 3. ( d ) Graph depicts the effect of addition of exogenous albumin on ACE2 activity (RFU) at different mouse rACE2 concentrations. Albumin at the indicated concentrations was added to urine samples (1 μl) from mice with gene deletion of ACE2. Results are means ± SEM; p > 0.05 for all graphs; n = 3

Article Snippet: ACE2 Standard: Recombinant human ACE2 (human rACE2, R&D Systems Inc., Minneapolis, MN, USA, Catalog Number: 933-ZN) and recombinant mouse ACE2 (mouse rACE2, R&D Systems Inc., Catalog Number: 3437-ZN).

Techniques: Activity Assay, Incubation

SARS-CoV-2 infection in male and female k18-hace2 mice over 7 days post-infection (dpi) (A) Body weight loss in response to intranasal inoculation of SARS-CoV-2 (4 × 10 5 TCID50/50μL/mouse). ∗p < 0.05 vs. male. Data represented in median ± IQR. (B) Lung injury scoring assessed on a scale of 0–4 for each of the following criteria: 1) neutrophil numbers in the alveolar space, 2) alveolar septal thickening, 3) number of hyaline membranes, 4) alveolar hemorrhage, and 5) cellular hyperplasia. ∗p < 0.05 vs. Ctrl and male. Data represented in mean ± SEM. (C) Viral RNA levels in oropharyngeal swabs at 2, 4, and 6 dpi. ∗p < 0.05 vs. male. Data represented in median ± IQR. (D–G) Copy numbers of E-gene and RdRp-gene in multiple organ tissues. ∗p < 0.05 vs. Ctrl. Data represented in mean ± SEM. (H) Detection of SARS-CoV-2 nucleocapsid protein (red) in lung tissues. Scale bars, 50 μm (main images) and 20 μm (magnified). (I) Protein expression in lung tissue detected by western blots in vehicle control (C) and at 7 dpi. (J) Concentration of soluble RAGE protein in plasma in vehicle control and at 7 dpi. ∗p < 0.05 vs. other groups. Data represented in mean ± SEM. (K) Correlation of protein levels of ACE2 and ERα in lung tissue of male mice before and after infection at 7 dpi. (L) Estrogen receptor alpha (ERα)/androgen receptor (AR) ratio assessed from western blot analysis in relation to β-actin loading control. ∗p < 0.05 vs. male. Data represented in mean ± SEM. (M) Concentration of 17β Estradiol in lung tissue homogenates in vehicle control and at 7 dpi. ∗p < 0.05 vs. male. n = 5–7 biologically independent mice for all groups. Data represented in mean ± SEM. (see also <xref ref-type=Figure S1 ). " width="100%" height="100%">

Journal: iScience

Article Title: Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

doi: 10.1016/j.isci.2023.107470

Figure Lengend Snippet: SARS-CoV-2 infection in male and female k18-hace2 mice over 7 days post-infection (dpi) (A) Body weight loss in response to intranasal inoculation of SARS-CoV-2 (4 × 10 5 TCID50/50μL/mouse). ∗p < 0.05 vs. male. Data represented in median ± IQR. (B) Lung injury scoring assessed on a scale of 0–4 for each of the following criteria: 1) neutrophil numbers in the alveolar space, 2) alveolar septal thickening, 3) number of hyaline membranes, 4) alveolar hemorrhage, and 5) cellular hyperplasia. ∗p < 0.05 vs. Ctrl and male. Data represented in mean ± SEM. (C) Viral RNA levels in oropharyngeal swabs at 2, 4, and 6 dpi. ∗p < 0.05 vs. male. Data represented in median ± IQR. (D–G) Copy numbers of E-gene and RdRp-gene in multiple organ tissues. ∗p < 0.05 vs. Ctrl. Data represented in mean ± SEM. (H) Detection of SARS-CoV-2 nucleocapsid protein (red) in lung tissues. Scale bars, 50 μm (main images) and 20 μm (magnified). (I) Protein expression in lung tissue detected by western blots in vehicle control (C) and at 7 dpi. (J) Concentration of soluble RAGE protein in plasma in vehicle control and at 7 dpi. ∗p < 0.05 vs. other groups. Data represented in mean ± SEM. (K) Correlation of protein levels of ACE2 and ERα in lung tissue of male mice before and after infection at 7 dpi. (L) Estrogen receptor alpha (ERα)/androgen receptor (AR) ratio assessed from western blot analysis in relation to β-actin loading control. ∗p < 0.05 vs. male. Data represented in mean ± SEM. (M) Concentration of 17β Estradiol in lung tissue homogenates in vehicle control and at 7 dpi. ∗p < 0.05 vs. male. n = 5–7 biologically independent mice for all groups. Data represented in mean ± SEM. (see also Figure S1 ).

Article Snippet: Male K18-hACE2 mice aged 8–10 weeks received soluble human recombinant ACE2 (rACE2, Apeiron Biologics, Vienna, Austria) either by intravenous injection (0.4 mg/kg) or nebulization (DD 12 mg/kg).

Techniques: Infection, Expressing, Western Blot, Control, Concentration Assay, Clinical Proteomics

Inhalation of rACE2 attenuates SARS-CoV-2 infection, replication, and lung injury and recovers expression of endogenous ACE2 and ERα in K18-hACE2 male mice at 7 dpi (A) Study scheme. Mice were intranasally inoculated with SARS-CoV-2 (4 × 10 5 TCID50/50μL/mouse) and 48 h later received daily nebulization of rACE2 (12 mg/kg) or vehicle control solution for 5 days. (B and C) Copy numbers of viral envelope (E) gene by RT-qPCR and titers (TCID50) in lung tissue in the SARS-CoV-2 infection alone and rACE2-treated groups. ∗p < 0.05 vs. SARS-CoV-2. Data represented in mean ± SEM. (D) Gene expression of IL-6 in lung tissue in the infection alone and rACE2-treated groups. ∗p < 0.05 vs. SARS-CoV-2. Data represented in mean ± SEM. (E) Concentration of soluble RAGE protein in plasma in infection alone and rACE2-treated mice. ∗p < 0.05 vs. SARS-CoV-2. Data represented in mean ± SEM. (F) Detection of SARS-CoV-2 nucleocapsid protein (red) in lung tissues. Scale bars, 50 μm (main images) and 20 μm (magnified). (G) Representative lung histology by H&E staining. Arrows indicate neutrophil infiltration in the alveolar space. Lung injury scores from 6 animals per group are also shown. ∗p < 0.05 vs. naive control (C), ♰p < 0.05 vs. SARS-CoV-2 alone & (C). Data represented in mean ± SEM. (H and I) Protein expression in lung tissue detected by western blots in naive control (C), SARS-CoV-2 (CoV2) alone, and rACE2-treated groups. ∗p < 0.05 vs. C & rACE2-treated groups. Data represented in mean ± SEM. (J and K). Fold changes in the concentrations of 17β Estradiol and ERα/AR ratio assessed from western blot analysis in relation to β-actin loading control in lung tissue in naive control (C), SARS-CoV-2 (CoV2) alone, and rACE2-treated groups. ∗p < 0.05 vs. C and SARS-CoV-2, respectively. n = 5–7 biologically independent mice for all groups. Data represented in mean ± SEM. (see also <xref ref-type=Figure S3 ). " width="100%" height="100%">

Journal: iScience

Article Title: Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

doi: 10.1016/j.isci.2023.107470

Figure Lengend Snippet: Inhalation of rACE2 attenuates SARS-CoV-2 infection, replication, and lung injury and recovers expression of endogenous ACE2 and ERα in K18-hACE2 male mice at 7 dpi (A) Study scheme. Mice were intranasally inoculated with SARS-CoV-2 (4 × 10 5 TCID50/50μL/mouse) and 48 h later received daily nebulization of rACE2 (12 mg/kg) or vehicle control solution for 5 days. (B and C) Copy numbers of viral envelope (E) gene by RT-qPCR and titers (TCID50) in lung tissue in the SARS-CoV-2 infection alone and rACE2-treated groups. ∗p < 0.05 vs. SARS-CoV-2. Data represented in mean ± SEM. (D) Gene expression of IL-6 in lung tissue in the infection alone and rACE2-treated groups. ∗p < 0.05 vs. SARS-CoV-2. Data represented in mean ± SEM. (E) Concentration of soluble RAGE protein in plasma in infection alone and rACE2-treated mice. ∗p < 0.05 vs. SARS-CoV-2. Data represented in mean ± SEM. (F) Detection of SARS-CoV-2 nucleocapsid protein (red) in lung tissues. Scale bars, 50 μm (main images) and 20 μm (magnified). (G) Representative lung histology by H&E staining. Arrows indicate neutrophil infiltration in the alveolar space. Lung injury scores from 6 animals per group are also shown. ∗p < 0.05 vs. naive control (C), ♰p < 0.05 vs. SARS-CoV-2 alone & (C). Data represented in mean ± SEM. (H and I) Protein expression in lung tissue detected by western blots in naive control (C), SARS-CoV-2 (CoV2) alone, and rACE2-treated groups. ∗p < 0.05 vs. C & rACE2-treated groups. Data represented in mean ± SEM. (J and K). Fold changes in the concentrations of 17β Estradiol and ERα/AR ratio assessed from western blot analysis in relation to β-actin loading control in lung tissue in naive control (C), SARS-CoV-2 (CoV2) alone, and rACE2-treated groups. ∗p < 0.05 vs. C and SARS-CoV-2, respectively. n = 5–7 biologically independent mice for all groups. Data represented in mean ± SEM. (see also Figure S3 ).

Article Snippet: Male K18-hACE2 mice aged 8–10 weeks received soluble human recombinant ACE2 (rACE2, Apeiron Biologics, Vienna, Austria) either by intravenous injection (0.4 mg/kg) or nebulization (DD 12 mg/kg).

Techniques: Infection, Expressing, Control, Quantitative RT-PCR, Gene Expression, Concentration Assay, Clinical Proteomics, Staining, Western Blot

Nebulization of rACE2 partially restores the ERα-associated signaling proteomic profiles in lung tissue at 7 dpi Proteomic analysis revealed that treatment with rACE2 resulted in an increase in 31 ERα-associated proteins and a decrease in 10 proteins. Of note, 16 of these proteins (highlighted in purple) were also found in female mice without rACE2 treatment at 7 dpi.

Journal: iScience

Article Title: Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

doi: 10.1016/j.isci.2023.107470

Figure Lengend Snippet: Nebulization of rACE2 partially restores the ERα-associated signaling proteomic profiles in lung tissue at 7 dpi Proteomic analysis revealed that treatment with rACE2 resulted in an increase in 31 ERα-associated proteins and a decrease in 10 proteins. Of note, 16 of these proteins (highlighted in purple) were also found in female mice without rACE2 treatment at 7 dpi.

Article Snippet: Male K18-hACE2 mice aged 8–10 weeks received soluble human recombinant ACE2 (rACE2, Apeiron Biologics, Vienna, Austria) either by intravenous injection (0.4 mg/kg) or nebulization (DD 12 mg/kg).

Techniques:

Treatment with rACE2 attenuates Delta variant replication and viral load and decreases cytopathic effects in human lung organoids (A) Human lung organoids expressing pro-surfactant protein C (SPC) and epithelial cell adhesion molecule (EpCAM). Scale bars, 20 μm (main images). (B) Representative images of human lung organoids in naive control (Ctrl, upper panel), Delta variant-challenged (middle panel), and treated with a pre-mixture of rACE2 (400 μg/mL) and Delta variant (1.8 × 10 7 TCID50/mL) for 30 min (lower panel). The expression of ACE2 (red) and viral nucleocapsid protein (green) were detected at 4 h post-infection. Scale bars, 5 μm. (see also <xref ref-type=Figure S4 ). (C) Levels of viral envelope (E) gene RNA were assessed by qRT-PCR after treatment with various concentrations of rACE2 in human lung organoids at 3 dpi. Supernatants of the Delta variant-infected lung organoids were collected and used to infect Vero E6 cells for TCID50 assay. ∗p < 0.05 vs. Mock; ♰ p < 0.05 vs. Delta variant alone. Data represented in mean ± SEM. (D) Representative images of cytopathic effects of human lung organoids in Delta variant infection and rACE2-treated groups at 3 dpi. Scale bars, 1000 μm (main images) and 400 μm (magnified). Data presented are representatives of three independent experiments. " width="100%" height="100%">

Journal: iScience

Article Title: Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

doi: 10.1016/j.isci.2023.107470

Figure Lengend Snippet: Treatment with rACE2 attenuates Delta variant replication and viral load and decreases cytopathic effects in human lung organoids (A) Human lung organoids expressing pro-surfactant protein C (SPC) and epithelial cell adhesion molecule (EpCAM). Scale bars, 20 μm (main images). (B) Representative images of human lung organoids in naive control (Ctrl, upper panel), Delta variant-challenged (middle panel), and treated with a pre-mixture of rACE2 (400 μg/mL) and Delta variant (1.8 × 10 7 TCID50/mL) for 30 min (lower panel). The expression of ACE2 (red) and viral nucleocapsid protein (green) were detected at 4 h post-infection. Scale bars, 5 μm. (see also Figure S4 ). (C) Levels of viral envelope (E) gene RNA were assessed by qRT-PCR after treatment with various concentrations of rACE2 in human lung organoids at 3 dpi. Supernatants of the Delta variant-infected lung organoids were collected and used to infect Vero E6 cells for TCID50 assay. ∗p < 0.05 vs. Mock; ♰ p < 0.05 vs. Delta variant alone. Data represented in mean ± SEM. (D) Representative images of cytopathic effects of human lung organoids in Delta variant infection and rACE2-treated groups at 3 dpi. Scale bars, 1000 μm (main images) and 400 μm (magnified). Data presented are representatives of three independent experiments.

Article Snippet: Male K18-hACE2 mice aged 8–10 weeks received soluble human recombinant ACE2 (rACE2, Apeiron Biologics, Vienna, Austria) either by intravenous injection (0.4 mg/kg) or nebulization (DD 12 mg/kg).

Techniques: Variant Assay, Expressing, Control, Infection, Quantitative RT-PCR, TCID50 Assay

Proposed mechanisms underlying biological sex differences in outcomes of SARS-CoV-2 and Delta variant infections and the therapeutic potential of inhaled ACE2 (A) Under physiological conditions, ACE2 catalyzes the conversion of Ang II to Ang1-7 for organ protection. The ACE2 gene is located at X chromosome p22.2, where genes are known to escape X-inactivation, contributing to phenotypic differences of ACE2 between biological sexes. Membrane expression of ACE2 can be upregulated by estrogens through estrogen receptor α (ERα), which exerts anti-inflammatory properties and further enhances organ protection. In contrast, androgen receptor (AR) can cleave ACE2 and mediate pro-inflammation and tissue injury. . (B) During SARS-CoV-2 infection, the virus binds to and decreases host cell surface ACE2. For a given infection, the reduction of endogenous ACE2 expression is associated with a dramatic decrease in ERα expression, resulting in loss of organ protection in males. In contrast, expression of endogenous ACE2 was sustained in females, potentially due to the extra X-linked ACE2 and well-maintained ERα expression, leading to compensatory mechanisms and persistent organ protection. (C) Inhalation of rACE2 can restore the balance of endogenous ACE2 and ERα by blocking or attenuating SARS-CoV-2 from binding to membrane ACE2 in males.

Journal: iScience

Article Title: Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

doi: 10.1016/j.isci.2023.107470

Figure Lengend Snippet: Proposed mechanisms underlying biological sex differences in outcomes of SARS-CoV-2 and Delta variant infections and the therapeutic potential of inhaled ACE2 (A) Under physiological conditions, ACE2 catalyzes the conversion of Ang II to Ang1-7 for organ protection. The ACE2 gene is located at X chromosome p22.2, where genes are known to escape X-inactivation, contributing to phenotypic differences of ACE2 between biological sexes. Membrane expression of ACE2 can be upregulated by estrogens through estrogen receptor α (ERα), which exerts anti-inflammatory properties and further enhances organ protection. In contrast, androgen receptor (AR) can cleave ACE2 and mediate pro-inflammation and tissue injury. . (B) During SARS-CoV-2 infection, the virus binds to and decreases host cell surface ACE2. For a given infection, the reduction of endogenous ACE2 expression is associated with a dramatic decrease in ERα expression, resulting in loss of organ protection in males. In contrast, expression of endogenous ACE2 was sustained in females, potentially due to the extra X-linked ACE2 and well-maintained ERα expression, leading to compensatory mechanisms and persistent organ protection. (C) Inhalation of rACE2 can restore the balance of endogenous ACE2 and ERα by blocking or attenuating SARS-CoV-2 from binding to membrane ACE2 in males.

Article Snippet: Male K18-hACE2 mice aged 8–10 weeks received soluble human recombinant ACE2 (rACE2, Apeiron Biologics, Vienna, Austria) either by intravenous injection (0.4 mg/kg) or nebulization (DD 12 mg/kg).

Techniques: Variant Assay, Membrane, Expressing, Infection, Virus, Blocking Assay, Binding Assay

Journal: iScience

Article Title: Inhalation of ACE2 as a therapeutic target on sex-bias differences in SARS-CoV-2 infection and variant of concern

doi: 10.1016/j.isci.2023.107470

Figure Lengend Snippet:

Article Snippet: Male K18-hACE2 mice aged 8–10 weeks received soluble human recombinant ACE2 (rACE2, Apeiron Biologics, Vienna, Austria) either by intravenous injection (0.4 mg/kg) or nebulization (DD 12 mg/kg).

Techniques: Virus, Isolation, Recombinant, Western Blot, Enzyme-linked Immunosorbent Assay, Plasmid Preparation, Software

Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or DX600 (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Standard curves for ACE2 activity assay. The assay was performed for 16 h incubation. Graph shows the concentrations of recombinant ACE2 (rACE2) versus the ACE2 activity (RFU). ( a ) Standard curves generated for human rACE2. The ACE2 inhibitors MLN-4760 (10 −6 M) or DX600 (10 −6 M) were used. The relationship is highly linear for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9998, p < 0.001 for MLN-4760, R 2 = 0.9999, p < 0.001 for DX600). ( b ) Standard curve generated for mouse rACE2. The ACE2 inhibitor MLN-4760 (10 −6 M) was used. A highly linear relationship exists for rACE2 concentrations between 0 and 50 ng/ml ( R 2 = 0.9976, p < 0.001)

Article Snippet: However, Ye et al. have reported that the disulfide bridged cyclic variant of DX600 (Bachem) had no inhibitory effect on mouse or rat ACE2, even at high concentrations, but effectively inhibited human rACE2 [ ].

Techniques: Activity Assay, Incubation, Recombinant, Generated

Effect of ACE2 inhibitors MLN-4760 (10 −6 M), DX600 (10 −6 M), and ACE inhibitor captopril (10 −5 M) on ACE2 enzyme activity. The assay was performed for 16 h incubation. Graph depicts the concentrations of recombinant ACE2 versus the Relative Fluorescence Units (RFU). A background RFU value (67.5 RFU for a , 62.0 RFU for b ) of the substrate blank control was subtracted from the readings for each well. ( a ) Effect of MLN-4760, DX600, and captopril on human rACE2 activity. ( b ) Effect of MLN-4760, DX600, and captopril on mouse rACE2 activity

Journal: Hypertension

Article Title: Measurement of Angiotensin Converting Enzyme 2 Activity in Biological Fluid (ACE2)

doi: 10.1007/978-1-4939-6625-7_8

Figure Lengend Snippet: Effect of ACE2 inhibitors MLN-4760 (10 −6 M), DX600 (10 −6 M), and ACE inhibitor captopril (10 −5 M) on ACE2 enzyme activity. The assay was performed for 16 h incubation. Graph depicts the concentrations of recombinant ACE2 versus the Relative Fluorescence Units (RFU). A background RFU value (67.5 RFU for a , 62.0 RFU for b ) of the substrate blank control was subtracted from the readings for each well. ( a ) Effect of MLN-4760, DX600, and captopril on human rACE2 activity. ( b ) Effect of MLN-4760, DX600, and captopril on mouse rACE2 activity

Article Snippet: However, Ye et al. have reported that the disulfide bridged cyclic variant of DX600 (Bachem) had no inhibitory effect on mouse or rat ACE2, even at high concentrations, but effectively inhibited human rACE2 [ ].

Techniques: Activity Assay, Incubation, Recombinant, Fluorescence, Control

Composition and function of the renin-angiotensin system and its main regulators and inhibitors. RAS: Rennin angiotensin system; ACEI: Angiotensin-converting enzyme inhibitor; ARB: Angiotensin II receptor blocker; ACE: Angiotensin-converting enzyme; ACE2: Angiotensin-converting enzyme 2; AT1R: Angiotensin type 1 receptor; AT2R: Angiotensin type 2 receptor; MasR: Mas receptor; MLN-4760: A specific ACE2 inhibitor; Organ damage: Renal damage, lung damage, cardiovascular damage, etc.

Journal: World Journal of Diabetes

Article Title: New perspectives on angiotensin-converting enzyme 2 and its related diseases

doi: 10.4239/wjd.v12.i6.839

Figure Lengend Snippet: Composition and function of the renin-angiotensin system and its main regulators and inhibitors. RAS: Rennin angiotensin system; ACEI: Angiotensin-converting enzyme inhibitor; ARB: Angiotensin II receptor blocker; ACE: Angiotensin-converting enzyme; ACE2: Angiotensin-converting enzyme 2; AT1R: Angiotensin type 1 receptor; AT2R: Angiotensin type 2 receptor; MasR: Mas receptor; MLN-4760: A specific ACE2 inhibitor; Organ damage: Renal damage, lung damage, cardiovascular damage, etc.

Article Snippet: Moreover, the prevention of Ang II-induced hypertension by mouse rACE2 was completely abolished by the specific ACE2 inhibitor MLN-4760, a nonpeptide inhibitor no longer available from Millennium Pharmaceuticals[ ].

Techniques:

List of animal studies on the high-sodium diet and  angiotensin-converting enzyme 2

Journal: World Journal of Diabetes

Article Title: New perspectives on angiotensin-converting enzyme 2 and its related diseases

doi: 10.4239/wjd.v12.i6.839

Figure Lengend Snippet: List of animal studies on the high-sodium diet and angiotensin-converting enzyme 2

Article Snippet: Moreover, the prevention of Ang II-induced hypertension by mouse rACE2 was completely abolished by the specific ACE2 inhibitor MLN-4760, a nonpeptide inhibitor no longer available from Millennium Pharmaceuticals[ ].

Techniques: Expressing, Staining

List of animal studies on renin angiotensin system inhibitors and  angiotensin-converting enzyme 2

Journal: World Journal of Diabetes

Article Title: New perspectives on angiotensin-converting enzyme 2 and its related diseases

doi: 10.4239/wjd.v12.i6.839

Figure Lengend Snippet: List of animal studies on renin angiotensin system inhibitors and angiotensin-converting enzyme 2

Article Snippet: Moreover, the prevention of Ang II-induced hypertension by mouse rACE2 was completely abolished by the specific ACE2 inhibitor MLN-4760, a nonpeptide inhibitor no longer available from Millennium Pharmaceuticals[ ].

Techniques: Ligation, Expressing

List of animal studies on the role of  angiotensin-converting enzyme 2  in diabetes, hypertension, cardiovascular disease, and acute lung injury

Journal: World Journal of Diabetes

Article Title: New perspectives on angiotensin-converting enzyme 2 and its related diseases

doi: 10.4239/wjd.v12.i6.839

Figure Lengend Snippet: List of animal studies on the role of angiotensin-converting enzyme 2 in diabetes, hypertension, cardiovascular disease, and acute lung injury

Article Snippet: Moreover, the prevention of Ang II-induced hypertension by mouse rACE2 was completely abolished by the specific ACE2 inhibitor MLN-4760, a nonpeptide inhibitor no longer available from Millennium Pharmaceuticals[ ].

Techniques: Control, Expressing, Isolation, Knock-Out, Injection, Clinical Proteomics, Activity Assay, Transgenic Assay, Generated, Activation Assay, Mutagenesis, Homologous Recombination, Plasmid Preparation, Over Expression, Suspension, Virus, Infection, Recombinant

List of epidemiological studies on the role of  angiotensin-converting enzyme 2  in diabetes, hypertension, cardiovascular disease, and acute lung injury

Journal: World Journal of Diabetes

Article Title: New perspectives on angiotensin-converting enzyme 2 and its related diseases

doi: 10.4239/wjd.v12.i6.839

Figure Lengend Snippet: List of epidemiological studies on the role of angiotensin-converting enzyme 2 in diabetes, hypertension, cardiovascular disease, and acute lung injury

Article Snippet: Moreover, the prevention of Ang II-induced hypertension by mouse rACE2 was completely abolished by the specific ACE2 inhibitor MLN-4760, a nonpeptide inhibitor no longer available from Millennium Pharmaceuticals[ ].

Techniques: Control, Expressing, Variant Assay, Methylation, Activity Assay, Clinical Proteomics, Concentration Assay