Journal: medRxiv

Article Title: The Contrasting Role of Nasopharyngeal Angiotensin Converting Enzyme 2 ( ACE2 ) Expression in SARS-CoV-2 Infection: A Cross-Sectional Study of People Tested for COVID-19 in British Columbia

doi: 10.1101/2020.11.23.20237206

Figure Lengend Snippet: The other does not include the transmembrane domain (pink) and lays nested between two motifs known to interact with the SARS-CoV receptor binding domain (blue). The measure of soluble ACE2 represents normalized expression of the pink to yellow target, or the proportion of non-transmembrane ACE2 to transmembrane ACE2 .

Article Snippet: Soluble ACE2 was defined as absolute relative expression between the Hs01085333_m1 (ThermoFisher) and HS01085340_m1 (ThermoFisher) gene targets ( ).

Techniques: Binding Assay, Expressing

Journal: medRxiv

Article Title: The Contrasting Role of Nasopharyngeal Angiotensin Converting Enzyme 2 ( ACE2 ) Expression in SARS-CoV-2 Infection: A Cross-Sectional Study of People Tested for COVID-19 in British Columbia

doi: 10.1101/2020.11.23.20237206

Figure Lengend Snippet: Boxplots of transmembrane ACE2 expression by nine-year age categories in COVID-19-negative participants between the ages of 19 and 98 (n=198); boxes represent the Q1-Q3 interquartile range, whiskers represent 1.5x the Q1 or Q3 and horizontal lines the median transmembrane ACE2 expression by age category. Nine-year categories were selected to optimize the distribution of observations between groups. Participants who tested negative younger than 19 or older than 98 were excluded based on n<10 observations per age group. No difference was detected in mean transmembrane ACE2 expression among age categories (ANOVA, P=0·092).

Article Snippet: Soluble ACE2 was defined as absolute relative expression between the Hs01085333_m1 (ThermoFisher) and HS01085340_m1 (ThermoFisher) gene targets ( ).

Techniques: Expressing

Journal: medRxiv

Article Title: The Contrasting Role of Nasopharyngeal Angiotensin Converting Enzyme 2 ( ACE2 ) Expression in SARS-CoV-2 Infection: A Cross-Sectional Study of People Tested for COVID-19 in British Columbia

doi: 10.1101/2020.11.23.20237206

Figure Lengend Snippet: Gene expression is portrayed in kernel density plots stratified by COVID-19 test result. Probability densities of relative host gene expression are shown by positive (red, transmembrane ACE2 ; blue, soluble ACE2 ; yellow, TMPRSS2 ) and negative COVID-19 test results (grey). Levene’s test was used to detect non-equal variance in gene expression for all host targets between COVID-19-negative and -positive participants. A two-tailed, t-test was used to examine mean difference in host gene expression by COVID-19 test result assuming unequal variance: transmembrane ACE2 (P=1·2e-4), soluble ACE2 (P<0·0001) and TMPRSS2 (P<0·0001).

Article Snippet: Soluble ACE2 was defined as absolute relative expression between the Hs01085333_m1 (ThermoFisher) and HS01085340_m1 (ThermoFisher) gene targets ( ).

Techniques: Gene Expression, Two Tailed Test

Journal: medRxiv

Article Title: The Contrasting Role of Nasopharyngeal Angiotensin Converting Enzyme 2 ( ACE2 ) Expression in SARS-CoV-2 Infection: A Cross-Sectional Study of People Tested for COVID-19 in British Columbia

doi: 10.1101/2020.11.23.20237206

Figure Lengend Snippet: The level of transmembrane ACE2 (red), soluble ACE2 (blue) and TMPRSS2 (black) expression in positive cases of COVID-19 and its relationship with SARS-CoV-2 RNA is shown in Log 10 genome equivalents per millilitre (GE/mL). Host gene expression was measured by quantitative real-time PCR and normalized to expression of the housekeeping gene GAPDH by the (2 -ΔΔCt ) method. Soluble ACE2 was defined as absolute relative expression between the Hs01085333_m1 (ThermoFisher) and HS01085340_m1 (ThermoFisher) gene targets . Simple linear regression was used estimate correlations, the reported P values are for the B eta-coefficients of host gene expression.

Article Snippet: Soluble ACE2 was defined as absolute relative expression between the Hs01085333_m1 (ThermoFisher) and HS01085340_m1 (ThermoFisher) gene targets ( ).

Techniques: Expressing, Gene Expression, Real-time Polymerase Chain Reaction

Journal: medRxiv

Article Title: The Contrasting Role of Nasopharyngeal Angiotensin Converting Enzyme 2 ( ACE2 ) Expression in SARS-CoV-2 Infection: A Cross-Sectional Study of People Tested for COVID-19 in British Columbia

doi: 10.1101/2020.11.23.20237206

Figure Lengend Snippet: Soluble ACE2 expression was categorized into low, mean and high levels to demonstrate the relationship. The low category (grey) represents soluble ACE2 expression two standard deviations below the mean expression. The mean category (orange) codes for the mean soluble ACE2 expression, zero standard deviations. The high category (blue) indicates soluble ACE2 expression two standard deviations above mean expression. Shaded areas represent 95% confidence intervals, solid lines represent B coefficients from multiple linear regression.

Article Snippet: Soluble ACE2 was defined as absolute relative expression between the Hs01085333_m1 (ThermoFisher) and HS01085340_m1 (ThermoFisher) gene targets ( ).

Techniques: Expressing

Journal: British journal of pharmacology

Article Title: Veklury® (remdesivir) formulations inhibit initial membrane-coupled events of SARS-CoV-2 infection due to their sulfobutylether-β-cyclodextrin content.

doi: 10.1111/bph.16063

Figure Lengend Snippet: FIGURE 1 Veklury® (remdesivir) formulations induce alterations in membrane structure and disrupt lipid rafts similarly to cyclodextrins (CDs) in a cholesterol-dependent manner independently of remdesivir. (a) Control HEK/ACE2 + TMPRSS2 cells and those treated with 1-, 5- or 10-mM MβCD, HPβCD, SBECD, Veklury® P (powder) or Veklury® S (solution), 100-μM remdesivir (REM) or 200-μM cholesterol (CHOL) were labelled with cholera toxin subunit B (CTX-B), a lipid raft marker, and N-[3-(40-dihexylamino-3-hydroxy-flavonyl-6-oxy)-propyl]N,N-dimethyl-N- (3-sulfopropyl)-ammonium inner salt (F66), an environment-sensitive fluorescent indicator. Representative confocal microscopic images taken from the flat, bottom membrane region adjacent to the coverslip show F66 intensities of the normal (N*) and tautomeric (T*) excited states and the T*/N* emission ratios calculated pixel by pixel. Cell membrane masks selected manually in CTX-B images were segmented using the maxentropy algorithm to ‘raft’ (CTX-B high) and ‘non-raft’ (CTX-B low) regions corresponding to high and low intensities of the raft markers, respectively, and average T*/N* intensity ratios were determined separately for the two masks (symbols in [c]). (b) Pixelwise distributions of the T*/N* F66 emission ratio in CTX-B high ‘raft’ and CTX-B low ‘non-raft’ regions of control cells are displayed. As an alternative definition for raft regions, a threshold value of the T*/N* ratio was determined (red dashed line) and membrane pixels were considered as ‘raft’ and ‘non-raft’ regions when being above and below the threshold, respectively (evaluation shown by the bars in [c]). The threshold value was chosen to result in a segmentation pattern similar to that obtained in (a). (c) The average F66 T*/N* ratios calculated for CTX-B high ‘raft’ and CTX-B low ‘non-raft’ pixels (circles and squares, respectively; numerical values to be read on the left vertical axis) as well as the relative fraction of ‘raft’ pixels (bars, numerical values to be read on the right vertical axis) above the F66 emission ratio threshold (shown by the red line in [b]) were determined in individual cells (n = 20) and the mean ± SD values are plotted. Asterisks indicate significant differences compared to the control samples (*P < 0.05; one-way ANOVA followed by Tukey's HSD test). See details of statistical analysis in Table S1.

Article Snippet: In general, reductions of internalization were higher in Calu-3 cells (at 5-mM CD, trimer uptake was reduced to 46%–58% for WT and 53%–67% for Delta) than in HEK/ACE2 + TMPRSS2 (for WT, significant differences were found between the two cell types after all examined CDs, whereas for Delta, in the cases of HPβCD and Veklury® P; P < 0.05).

Techniques: Membrane, Control, Marker

Journal: British journal of pharmacology

Article Title: Veklury® (remdesivir) formulations inhibit initial membrane-coupled events of SARS-CoV-2 infection due to their sulfobutylether-β-cyclodextrin content.

doi: 10.1111/bph.16063

Figure Lengend Snippet: FIGURE 2 Methyl-β cyclodextrin (MβCD)-induced reductions in ACE2 binding of Wuhan-Hu-1 strain of SARS-CoV-2 (WT) and Delta SARS- CoV-2 spike receptor-binding domains (RBDs) negatively correlate with the applied RBD concentrations. HEK/ACE2 + TMPRSS2 cells were treated with different concentrations of MβCD ranging between 0.25 and 10 mM. Fluorescence intensities of cells were measured using flow cytometry for 5 min continuously starting immediately after the addition of GFP-conjugated WT (a) or Delta (b) SARS-CoV-2 spike RBDs applied at various concentrations between 0.1 and 5 μgml1, or 0.05 and 2.5 μgml1, respectively. Moving averages of time-correlated fluorescence intensities of at least 50,000 cells of normal morphology were determined with a window size of 10 s and subsequently normalized to the average of intensities obtained in the last time window of untreated control samples. Mean ± SD values were calculated from data of six independent samples per treatment condition and plotted as a function of time (starting 20 s after RBD addition). The extents of inhibition of WT (a) and Delta (b) RBD binding at the end of the measurement time in response to various MβCD concentrations were calculated and plotted as mean ± SD as a function of the applied RBD concentration in the right panels. Asterisks indicate significant differences of samples treated with the lowest versus highest RBD concentrations at each applied CD concentration (*P < 0.05; two-way ANOVA followed by Tukey's HSD test). See details of statistical analysis in Table S2.

Article Snippet: In general, reductions of internalization were higher in Calu-3 cells (at 5-mM CD, trimer uptake was reduced to 46%–58% for WT and 53%–67% for Delta) than in HEK/ACE2 + TMPRSS2 (for WT, significant differences were found between the two cell types after all examined CDs, whereas for Delta, in the cases of HPβCD and Veklury® P; P < 0.05).

Techniques: Binding Assay, Fluorescence, Flow Cytometry, Control, Inhibition, Concentration Assay

Journal: British journal of pharmacology

Article Title: Veklury® (remdesivir) formulations inhibit initial membrane-coupled events of SARS-CoV-2 infection due to their sulfobutylether-β-cyclodextrin content.

doi: 10.1111/bph.16063

Figure Lengend Snippet: FIGURE 3 Veklury® (remdesivir) formulations and cyclodextrin (CDs) reduce the cellular binding of Wuhan-Hu-1 strain of SARS-CoV-2 (WT) and Delta SARS-CoV-2 spike receptor-binding domain (RBDs) in a cholesterol-dependent manner. HEK/ACE2 + TMPRSS2 (a) or Calu-3 (b) cells were treated with a dilution series of MβCD, HPβCD, SBECD, Veklury® P (powder), Veklury® S (solution) or a 1:1 (w/w) mixture of Veklury® P and SBECD at CD concentrations ranging between 0.078 and 20 mM, remdesivir (REM) between 75 and 1200 μM or cholesterol (CHOL) between 12.5 and 800 μM. HEK/ACE2 + TMPRSS2 cells were incubated in the presence of 0.2-μgml1 WT or 0.1-μgml1 Delta SARS-CoV-2 spike RBD–GFP, whereas Calu-3 cells were labelled with 1-μgml1 WT or 0.5-μgml1 Delta RBD–GFP for 4 min. The emitted fluorescence intensities of individual cells were subsequently measured using flow cytometry and the mean intensity was calculated from data of at least 10,000 cells of normal morphology per sample. The average values of six independent measurements (±SD) were calculated, normalized to the mean value determined in untreated control samples and plotted as a function of the applied concentrations of CD (in the left panels) and CHOL or REM (in the right panels). Asterisks indicate significant differences of samples treated with the highest applied concentrations compared to the control samples (*P < 0.05; two-way ANOVA followed by Tukey's HSD test). See details of statistical analysis in Table S3.

Article Snippet: In general, reductions of internalization were higher in Calu-3 cells (at 5-mM CD, trimer uptake was reduced to 46%–58% for WT and 53%–67% for Delta) than in HEK/ACE2 + TMPRSS2 (for WT, significant differences were found between the two cell types after all examined CDs, whereas for Delta, in the cases of HPβCD and Veklury® P; P < 0.05).

Techniques: Binding Assay, Incubation, Fluorescence, Flow Cytometry, Control

Journal: British journal of pharmacology

Article Title: Veklury® (remdesivir) formulations inhibit initial membrane-coupled events of SARS-CoV-2 infection due to their sulfobutylether-β-cyclodextrin content.

doi: 10.1111/bph.16063

Figure Lengend Snippet: FIGURE 6 Veklury® (remdesivir) formulations effectively decrease ACE2 binding of Omicron SARS-CoV-2 spike receptor-binding domain (RBD) and the cellular uptake of Omicron SARS-CoV-2 spike trimer due to their SBECD content. (a) HEK/ACE2 + TMPRSS2 (left panel) or Calu-3 cells (right panel) were treated with SBECD, Veklury® P (powder) or Veklury® S (solution) at CD concentrations of 1, 5 and 10 mM. Then, HEK/ ACE2 + TMPRSS2 cells were incubated in the presence of 0.2-μgml1 Omicron SARS-CoV-2 spike RBD–GFP, whereas Calu-3 cells were labelled with 1-μgml1 Omicron RBD–GFP for 4 min. The emitted fluorescence intensities of individual cells were subsequently measured using flow cytometry, and the mean intensity was calculated from data of at least 10,000 cells of normal morphology per sample. The average values of six independent measurements (±SD) were calculated, normalized to the mean value determined in untreated control samples and plotted as a function of the applied concentrations of CD. Asterisks indicate significant differences of samples treated with the highest applied concentrations compared to the control samples (*P < 0.05; two-way ANOVA followed by Tukey's HSD test). See details of statistical analysis in Table S6. (b) HEK/ACE2 + TMPRSS2 (left panel) or Calu-3 cells (right panel) treated with SBECD, Veklury® P or Veklury® S at CD concentrations of 1 and 5 mM for 1 h were subsequently incubated for 4 h in the presence of Omicron SARS-CoV-2 spike trimers conjugated with Alexa Fluor 488. The average fluorescence intensity values emitted by Alexa Fluor 488-labelled trimers were calculated using data of intracellular pixels identified using the membrane marker N-[3-(40-dihexylamino-3-hydroxy-flavonyl-6-oxy)-propyl]N,N-dimethyl-N-(3-sulfopropyl)-ammonium inner salt (F66) as described in Figure 5 for individual cells, which were subsequently normalized to the median value determined in untreated control samples. The number of cells obtained from five independent experiments and involved in the analysis was from left to right: 382, 348, 373, 396, 388, 402 and 393 for Omicron trimer uptake in HEK/ACE2 + TMPRSS2 and 308, 250, 256, 223, 222, 232 and 296 for Omicron trimer uptake in Calu-3. Data points indicated in the figure were obtained from individual cells and plotted along with median values with quartiles. Grey shaded areas show ranges between 0.5 and 1. Asterisks indicate significant differences compared to the control samples (*P < 0.05; one-way ANOVA followed by Tukey's HSD test). See details of statistical analysis in Table S6.

Article Snippet: In general, reductions of internalization were higher in Calu-3 cells (at 5-mM CD, trimer uptake was reduced to 46%–58% for WT and 53%–67% for Delta) than in HEK/ACE2 + TMPRSS2 (for WT, significant differences were found between the two cell types after all examined CDs, whereas for Delta, in the cases of HPβCD and Veklury® P; P < 0.05).

Techniques: Binding Assay, Incubation, Fluorescence, Flow Cytometry, Control, Membrane, Marker

Journal: Advanced Therapeutics

Article Title: Discovery of Small Anti‐ACE2 Peptides to Inhibit SARS‐CoV‐2 Infectivity

doi: 10.1002/adtp.202100087

Figure Lengend Snippet: Discovery of anti‐ACE2 peptides using phage display biopanning. a) Schematic of blocking SARS‐CoV‐2 infections by anti‐ACE2 peptides. b) The number of eluted phages after each round of biopanning. c) Sequences of identified anti‐ACE2 peptides. d) Blocking effect of the anti‐ACE2 peptides (10 × 10 −6 m ) and an anti‐ACE2 antibody (200 × 10 −9 m ) on the SARS‐CoV‐2‐RBD/ACE2 interaction. All results are presented as the mean ± SD ( n = 3).

Article Snippet: Competition SPR was used to assess the ability of the anti‐ACE2 peptides to block the interaction between human ACE2 (catalog# AC2‐H52H8, Acro Biosystems, Newark, DE) and SARS‐CoV‐2 S protein RBD.

Techniques: Blocking Assay

Journal: Advanced Therapeutics

Article Title: Discovery of Small Anti‐ACE2 Peptides to Inhibit SARS‐CoV‐2 Infectivity

doi: 10.1002/adtp.202100087

Figure Lengend Snippet: Blockade assay of the SARS‐CoV‐2‐RBD/ACE2 and SARS‐CoV‐1‐RBD/ACE2 interactions by anti‐ACE2 peptides. Blocking efficiency and IC 50 of a) the anti‐ACE2 antibody, b) CPS4 peptide, c) CPS13 peptide, and d) the dimer of CPS4 peptide against the SARS‐CoV‐2‐RBD/ACE2 interaction. Blocking efficiency and IC 50 of e) the CPS4 peptide and f) CPS4 dimer against the SARS‐CoV‐1‐RBD/ACE2 interaction. All results are presented as the mean ± SD ( n = 3).

Article Snippet: Competition SPR was used to assess the ability of the anti‐ACE2 peptides to block the interaction between human ACE2 (catalog# AC2‐H52H8, Acro Biosystems, Newark, DE) and SARS‐CoV‐2 S protein RBD.

Techniques: Blocking Assay

Journal: Advanced Therapeutics

Article Title: Discovery of Small Anti‐ACE2 Peptides to Inhibit SARS‐CoV‐2 Infectivity

doi: 10.1002/adtp.202100087

Figure Lengend Snippet: Evaluation of binding affinity and blocking efficiency of the peptides to ACE2 using competition SPR. a) Schematic of the competition of SPR. b) SPR sensorgram, c) response curve, and d) blocking curve of the CSP4 peptide. e) SPR sensorgram, f) response curve, and g) blocking curve of the CSP4 peptide dimer. All results are presented as the mean ± SD ( n = 3).

Article Snippet: Competition SPR was used to assess the ability of the anti‐ACE2 peptides to block the interaction between human ACE2 (catalog# AC2‐H52H8, Acro Biosystems, Newark, DE) and SARS‐CoV‐2 S protein RBD.

Techniques: Binding Assay, Blocking Assay

Journal: Advanced Therapeutics

Article Title: Discovery of Small Anti‐ACE2 Peptides to Inhibit SARS‐CoV‐2 Infectivity

doi: 10.1002/adtp.202100087

Figure Lengend Snippet: Binding specificity of anti‐ACE2 peptides to ACE2. Percent of A549 and A549/ACE2 cells that bind to Cy5‐labeled peptides a) CSP4, b) CSP13, and c) CSP4 dimer at different concentrations and their corresponding histogram plots. Statistical significance was determined by two‐tailed Student's t ‐test (** P < 0.01). d) Representative western blot images of ACE2 expression levels in A549, A549/ACE2, DU‐145, Vero‐E6, and Huh‐7 cells. e) Binding of CSP4 dimer at different concentrations (500 × 10 −9 , 1000 × 10 −9 , and 2000 × 10 −9 m ) to A549, A549/ACE2, DU‐145, Vero‐E6, and Huh‐7 cells. All results are presented as the mean ± SD ( n = 3).

Article Snippet: Competition SPR was used to assess the ability of the anti‐ACE2 peptides to block the interaction between human ACE2 (catalog# AC2‐H52H8, Acro Biosystems, Newark, DE) and SARS‐CoV‐2 S protein RBD.

Techniques: Binding Assay, Labeling, Two Tailed Test, Western Blot, Expressing

Journal: Advanced Therapeutics

Article Title: Discovery of Small Anti‐ACE2 Peptides to Inhibit SARS‐CoV‐2 Infectivity

doi: 10.1002/adtp.202100087

Figure Lengend Snippet: Safety and stability evaluation of the anti‐ACE2 peptides. a) Cytotoxicity of CSP4, CSP13, and CSP4 dimer peptides in Vero‐E6 cells at different concentrations. Triton X‐100 was used as a positive control. b) Cytotoxicity of CSP4, CSP13, and CSP4 dimer peptides in Huh‐7 cells at different concentrations. Triton X‐100 was used as a positive control. Representative H&E staining of lung specimens from the mice (3–4 mice per group) 72 h after intratracheal administration of c) saline, d) CSP4, and e) CSP4 dimer peptides (Scale bar: 100 µm). The peptides were administrated at a dose of 2 mg kg −1 . f) Inflammation scores (0–5 scale) of the lung specimens. g) Stability of CSP4 dimer peptide in PBS and human serum. h) Effect of anti‐ACE2 peptides on ACE2 enzyme activity. The ACE2 inhibitor MLN‐4760 was used as a positive control. Cytotoxicity and ACE2 enzyme activity results are presented as the mean ± SD ( n = 3). Statistical significance was determined by one‐way ANOVA (a, b, f, and h) with Tukey's multiple comparison. ** p < 0.01.

Article Snippet: Competition SPR was used to assess the ability of the anti‐ACE2 peptides to block the interaction between human ACE2 (catalog# AC2‐H52H8, Acro Biosystems, Newark, DE) and SARS‐CoV‐2 S protein RBD.

Techniques: Positive Control, Staining, Saline, Activity Assay, Comparison

Journal: Advanced Therapeutics

Article Title: Discovery of Small Anti‐ACE2 Peptides to Inhibit SARS‐CoV‐2 Infectivity

doi: 10.1002/adtp.202100087

Figure Lengend Snippet: The CSP4 dimer inhibits the infectivity of SARS‐CoV‐2 in Vero‐E6 cells. Vero‐E6 cells were incubated with the anti‐ACE2 peptides at 37 ℃ for 1 h, followed by incubation with 100 pfu of SARS‐CoV‐2 virus at 37 ℃ for 1 h. After removing the virus, overlay media were added, and the plate were incubated at 37 ℃ for 4 d. The cells were then stained, and plaques were counted to determine the inhibitory effect of the peptides. The results are presented as the mean ± SD ( n = 3).

Article Snippet: Competition SPR was used to assess the ability of the anti‐ACE2 peptides to block the interaction between human ACE2 (catalog# AC2‐H52H8, Acro Biosystems, Newark, DE) and SARS‐CoV‐2 S protein RBD.

Techniques: Infection, Incubation, Virus, Staining

Journal: International Journal of Molecular Sciences

Article Title: Artificial Intelligence Reveals Nature: Functional Parallels Between a Designed and a Natural Peptide

doi: 10.3390/ijms262110607

Figure Lengend Snippet: RBD-ACE2 interaction inhibition assays. ( a ) Schematic illustration of ELISA experiment to evaluate the ability of the A13 or Nat1 to prevent the interaction of SARS-CoV-2 S1 protein RBD to human receptor ACE2. First the plates were incubated with immobilized RBD. They were then inoculated with peptides prior to the addition of recombinant human receptor ACE2. ( b ) Inhibition of RBD-ACE2 binding via A13 or Nat1. The level of RBD-ACE2 binding was measured by chemiluminescence. The negative control with no peptide representing RBD-ACE2 interaction was set to 1.00 (3.2 × 10 4 RLU) and other values were normalized to this number. To the same extent, at the concentration of 0.1 µg/mL, both peptides reduced ACE2 binding compared to the control. At 1.0 µg/mL, inhibition was further enhanced. The negative control peptide did not exhibit a notable inhibition. Data represent the mean value from at least three independent experiments. Error bars represent standard deviation. Statistical significance was determined using the nonparametric two-tailed Student’s t -test (**** p ≤ 0.0001).

Article Snippet: The ability of the peptides to block the interaction between the RBD and ACE2 was assessed using a commercial ACE2 inhibition assay kit (BPS Bioscience, San Diego, CA, United States, CAT# 79931).

Techniques: Inhibition, Enzyme-linked Immunosorbent Assay, Incubation, Recombinant, Binding Assay, Negative Control, Concentration Assay, Control, Standard Deviation, Two Tailed Test

Journal: International Journal of Molecular Sciences

Article Title: Artificial Intelligence Reveals Nature: Functional Parallels Between a Designed and a Natural Peptide

doi: 10.3390/ijms262110607

Figure Lengend Snippet: NanoLuc bioreporter assays. ( a ) A schematic illustration for the NanoLuc bioreporter assay to determine SARS-CoV-2 S1 RBD—ACE2 inhibition by A13 or Nat1. ( b ) NanoLuc bioreporter assay indicates that both peptides reduce luciferase complementation to the same extent. The signal value for no peptide control was set to 1.00 (6.30 × 10 5 RLU) and all other values were normalized to it. In cell lysates, A13 and Nat1 both reduced luminescence, indicating inhibition of RBD-ACE2 binding. The negative control peptide had no significant effect. Data represent the mean value from at least three independent experiments. Error bars represent standard deviation. Statistical significance was determined using the nonparametric two-tailed Student’s t -test (**** p ≤ 0.0001, ** p ≤ 0.01).

Article Snippet: The ability of the peptides to block the interaction between the RBD and ACE2 was assessed using a commercial ACE2 inhibition assay kit (BPS Bioscience, San Diego, CA, United States, CAT# 79931).

Techniques: Inhibition, Luciferase, Control, Binding Assay, Negative Control, Standard Deviation, Two Tailed Test

Journal: International Journal of Molecular Sciences

Article Title: Artificial Intelligence Reveals Nature: Functional Parallels Between a Designed and a Natural Peptide

doi: 10.3390/ijms262110607

Figure Lengend Snippet: Pseudovirus infectivity assays. ( a ) A schematic illustration for pseudovirus infectivity assay to determine the inhibition ability of the peptides to prevent psuedovirus to enter the cell. ( b ) Pseudovirus infectivity assays indicates that both peptides exhibit similar effects on pseudovirus infected cells. The signal value for pseudovirus infection with no peptide was set to 1.00 and corresponding values were normalized to it. Cells were incubated with pseudovirus in the absence/presence of A13 or Nat1, and infection was measured using a luciferase reporter. Both peptides reduce pseudovirus entry into ACE2-expressing cells. Neither peptide shows any visible effects on the non-peptide sample. Data represents the mean value from at least three independent experiments. Error bars represent standard deviation. Statistical significance was determined using the nonparametric two-tailed Student’s t -test (**** p ≤ 0.0001, ** p ≤ 0.01).

Article Snippet: The ability of the peptides to block the interaction between the RBD and ACE2 was assessed using a commercial ACE2 inhibition assay kit (BPS Bioscience, San Diego, CA, United States, CAT# 79931).

Techniques: Infection, Inhibition, Incubation, Luciferase, Expressing, Standard Deviation, Two Tailed Test