Journal: Cell Reports

Article Title: Isolation and characterization of cross-neutralizing coronavirus antibodies from COVID-19+ subjects

doi: 10.1016/j.celrep.2021.109353

Figure Lengend Snippet: Epitope specificities and cross-reactivity of SARS-CoV-2 Abs The percentage of mAbs from each donor specific for the SARS-CoV-2 spike subdomains and their cross-reactivity was determined by biolayer interferometry (BLI). (A) Using S1 and S2 monomer proteins, mAbs were grouped into the Abs that bound the RBD in the S1 subunit (S1: RBD, blue), mAbs that bound S1 outside of the RBD (S1: non-RBD, teal), mAbs that bound the S2 ECD (S2 ECD, yellow), or those that bound S2P but did not bind either S1 or S2 (S2P: Non-S1/Non-S2). (B) The percentage of mAbs that bind to SARS-CoV-1, MERS, and the four common human coronavirus was also measured by BLI using S2-P timers for SARS-CoV1 and MERS and S1+S2 monomers for the four human coronavirus antigens. (C) The percentage of mAbs that bound each subdomain of the coronavirus spike for the mAbs cross-reactive with SARS-CoV-1, MERS S-2P, and the four common human coronaviruses. Only mAbs isolated from the four SARS-CoV-2-infected donors are included. Significant differences were determined using two-way ANOVA with Tukey’s multiple comparison test. ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001, ∗∗∗∗ p < 0.0001. Additional BLI data and comparison to number of amino acid mutations in Figure S3 .

Article Snippet: SARS-CoV-1 RBD , Sino biologics , Cat#: 40150-V08B2.

Techniques: Isolation, Infection

Journal: Cell Reports

Article Title: Isolation and characterization of cross-neutralizing coronavirus antibodies from COVID-19+ subjects

doi: 10.1016/j.celrep.2021.109353

Figure Lengend Snippet: SARS-CoV-1 and SARS-COV-2 cross-neutralizing properties of mAbs The 14 neutralizing mAbs were characterized. (A) Percentage of mAbs capable of achieving 50% neutralization of SARS-CoV-2 pseudovirus at a concentration of 50 μg/ml from each donor. (B) The IC 50 s of each nAb in comparison to a negative control (AMMO1) are graphed. Each data point represents an independent replicate, with the mean and SD indicated with error bars. The non-RBD-binding mAbs, CV1-1 and CV3-25, on the left side of the graph are separated by a dashed line from the RBD-binding mAbs on the right side of graph. (C) SARS-CoV-2 neutralizing mAbs were assessed for their ability to neutralize SARS-CoV-1. CR3022 is a control SARS-CoV-1 neutralizing mAb. Horizontal line indicates mean with error bars at SD. Full data in A–S4D. (D) The IC 50 s of the iGL versions of the mAbs (open dots) are compared to IC 50 s of mutated mAbs (solid dots). Additional data in Figure S5 . (E) Competition of mAbs for binding to ACE2. mAbs that show competition have a binding signal below the dotted line and block ACE2 binding, and mAbs with a binding signal above the dotted line enhance ACE2 binding by increasing avidity through immune complex formation. Competition is calculated as the area under the curve (AUC) of mAb binding to the RBD in the presence of ACE2 divided by the AUC of mAb binding to RBD alone. Dots are shown as the median of two replicates, with SD indicated by error bars. The dotted line at the RBD-alone condition indicates BLI signal of uninhibited RBD:ACE2 binding. The NTD-specific CV1-1 mAb is used a negative control. (F) Correlation between SARS-CoV-2 neutralization IC 50 with AUC of the BLI of competition with ACE2 for RBD binding. R 2 value for nonlinear fit and Spearmen correlation p value are shown. (G) The competition of mAbs for binding to SARS-CoV-1 RBD with ACE2 is compared on this graph performed as in (E). Full ACE2 competition data in F–S4J. Additional characterization of CV1-1 and CV2-75 in Figure S6 .

Article Snippet: SARS-CoV-1 RBD , Sino biologics , Cat#: 40150-V08B2.

Techniques: Neutralization, Concentration Assay, Negative Control, Binding Assay, Blocking Assay

Journal: Cell Reports

Article Title: Isolation and characterization of cross-neutralizing coronavirus antibodies from COVID-19+ subjects

doi: 10.1016/j.celrep.2021.109353

Figure Lengend Snippet: Neutralization of the mutant B.1.351 variant The SARS-CoV-1 neutralizing mAbs were tested against the B.1.351 strain. (A) CV2-71. (B) CV2-75. (C) CV3-17. (D) CV3-25. Graphs show neutralization curves for the Wuhan strain of SARS-CoV-2 in blue and the curve for the B.1.351 strain in red. Bars indicate SD.

Article Snippet: SARS-CoV-1 RBD , Sino biologics , Cat#: 40150-V08B2.

Techniques: Neutralization, Mutagenesis, Variant Assay

Journal: Nature communications

Article Title: Ultrapotent SARS coronavirus-neutralizing single-domain antibodies that clamp the spike at its base.

doi: 10.1038/s41467-025-60250-1

Figure Lengend Snippet: Fig. 6 | X-ray structure of the R3DC23 – HR2 complex. a left: model of full-length prefusion S (6VSB_1_1_269) with superimposition of the R3DC23 – HR2 complex, all shown in molecular surface representation, with N-glycans in stick representation. R3DC23 VHHs are colored in orange, labeled S protein regions: cytoplasmic domain (red; CP), transmembrane domain (gray; TM), heptad repeat 2 (blue; HR2), S2 stem helix (deep pink; SH), heptad repeat 1 (lemon, HR1), central helix and connector domain (pink; CH-CD), the S1 regions encompassing the N-terminal domain (NTD) and receptor binding domain (RBD) (light blue). Right: model of the proteolytically processed postfusion S2 subunit (7E9T70), color coded as in prefusion spike. b Side and axial view (inset) of the R3DC23 – HR2 complex (sand and blue, respectively)

Article Snippet: Wells of microtiter plates (type II, F96 Maxisorp, Nunc) were coated overnight at 4 °C with 100ng of recombinant SARS-Cov-2 S-2P, SARSCoV-2 S-6P protein, recombinant SARS-CoV-1 spike protein, recombinant MERS-CoV spike protein, recombinant HKU1 spike protein (all kindly provided by Dr. Jason McLellan), SARS-CoV-2 Omicron BA.1 S protein (ACROBiosystems), mouse Fc-tagged SARS-CoV-2 RBD (Sino Biological, 40592-V05H), the SARS-CoV-2 spike S2 subunit (ACROBiosystems, S2NC52H5) or BSA.

Techniques: Labeling, Binding Assay

Journal: Biosensors & Bioelectronics

Article Title: Magnetic beads combined with carbon black-based screen-printed electrodes for COVID-19: A reliable and miniaturized electrochemical immunosensor for SARS-CoV-2 detection in saliva

doi: 10.1016/j.bios.2020.112686

Figure Lengend Snippet: The MBs-based assay for SARS-CoV-2 detection in untreated saliva.

Article Snippet: The use of the high sensitive antibodies is one of the main task to develop high sensitive and selective analytical device, thus for the selection of antibodies, spectrophotometric ELISA was carried out to assess the reactivity of MAb and two different PAb (Sinobiological, Germany and ProSci, USA) towards two different S proteins namely SARS Coronavirus 2019 Spike Recombinant protein (1000–1200 aa) and Recombinant Spike protein SARS-CoV Spike protein, S1 subunit.

Techniques:

Journal: Biosensors & Bioelectronics

Article Title: Magnetic beads combined with carbon black-based screen-printed electrodes for COVID-19: A reliable and miniaturized electrochemical immunosensor for SARS-CoV-2 detection in saliva

doi: 10.1016/j.bios.2020.112686

Figure Lengend Snippet: A) ELISA response for two different PAb anti-SARS-CoV-2 1 μg/mL (Sinobiological and ProSci) towards two different Spike proteins coated at 2 ng/mL. B) Binding curve of colorimetric ELISA for MAb anti-SARS-CoV-2 ranging from 0.12 – 2 μg/mL. Coating of Spike protein: 2 ng/mL. C) Electrochemical response using the MBs-based assay using CB-based modified electrode (blue line) and bare electrode (black line). The mean value (n = 3) with the corresponding standard deviation was reported for each measurement. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Article Snippet: The use of the high sensitive antibodies is one of the main task to develop high sensitive and selective analytical device, thus for the selection of antibodies, spectrophotometric ELISA was carried out to assess the reactivity of MAb and two different PAb (Sinobiological, Germany and ProSci, USA) towards two different S proteins namely SARS Coronavirus 2019 Spike Recombinant protein (1000–1200 aa) and Recombinant Spike protein SARS-CoV Spike protein, S1 subunit.

Techniques: Enzyme-linked Immunosorbent Assay, Binding Assay, Modification, Standard Deviation

Journal: Biosensors & Bioelectronics

Article Title: Magnetic beads combined with carbon black-based screen-printed electrodes for COVID-19: A reliable and miniaturized electrochemical immunosensor for SARS-CoV-2 detection in saliva

doi: 10.1016/j.bios.2020.112686

Figure Lengend Snippet: A) Study of the signal response for evaluating PAb concentration. 10 μL of MBs, 200 μL of PAb anti SARS-CoV-2 0.5, 1, and 2 μg/mL (in PBS) + 200 μL of PAb-AP anti rabbit IgG 0.5, 1, and 2 μg/mL (in PBS) + 300 μL of tested sample, incubation time 30 min without stirring, 3 washing steps, testing a negative control and 0.16 μg/mL of S protein. B) Study of the signal response for evaluating the effect of incubation time. 10 μL of MBs, 200 μL of PAb anti SARS-CoV-2 1 μg/mL (in PBS) + 200 μL of PAb-AP anti rabbit IgG 1 μg/mL (in PBS) + 300 μL of tested sample, incubation time (15/30 min) without stirring, 3 washing steps, testing a negative control, 0.16 and 2.5 μg/mL of S protein. C) Study of the signal response as function of mixing during the incubation step. 10 μL of MBs, 200 μL of PAb anti SARS-CoV-2 1 μg/mL (in PBS) + 200 μL of PAb-AP anti rabbit IgG 1 μg/mL (in PBS) + 300 μL of tested sample, incubation time 30 min with and without stirring, 3 washing steps, testing a negative control and 0.16 and 2.5 μg/mL of S protein. D) Study of the signal response for evaluating the effect of number of washing steps. 10 μL of MBs, 200 μL of PAb anti SARS-CoV-2 1 μg/mL (in PBS) + 200 μL of PAb-AP anti rabbit IgG 1 μg/mL (in PBS) + 300 μL of tested sample, incubation time 30 min without stirring, 1/2/3 washing steps, testing a negative control and 0.16 μg/mL of S protein. The mean value (n = 3) with the corresponding standard deviation was reported for each measurement.

Article Snippet: The use of the high sensitive antibodies is one of the main task to develop high sensitive and selective analytical device, thus for the selection of antibodies, spectrophotometric ELISA was carried out to assess the reactivity of MAb and two different PAb (Sinobiological, Germany and ProSci, USA) towards two different S proteins namely SARS Coronavirus 2019 Spike Recombinant protein (1000–1200 aa) and Recombinant Spike protein SARS-CoV Spike protein, S1 subunit.

Techniques: Concentration Assay, Incubation, Negative Control, Standard Deviation

Journal: Biosensors & Bioelectronics

Article Title: Magnetic beads combined with carbon black-based screen-printed electrodes for COVID-19: A reliable and miniaturized electrochemical immunosensor for SARS-CoV-2 detection in saliva

doi: 10.1016/j.bios.2020.112686

Figure Lengend Snippet: A) Electrochemical calibration curve (inset the voltammograms) using the optimized parameters for S protein detection in buffer (black line) and in untreated saliva (red line) (n = 3). B) Electrochemical calibration curve (inset the voltammograms) for N protein detection in buffer (black line) and untreated saliva (red line) (n = 3). C) Voltammograms obtained without (black line) and with (blue line) cultured SARS-CoV-2 virus at concentration 6.5 PFU/mL using MBs-based immunoassay for S protein. D) Voltammograms obtained without (black line) and with (blue line) cultured SARS-CoV-2 virus at concentration 6.5 x 10 4 PFU/mL using MBs-based immunoassay for N protein. E) Exclusivity test on seasonal influenza virus A (H1N1) (10 2.9 TCID50 mL −1 ) and Influenza 2009 pH1N1 virus (10 4.15 TCID50 mL −1 ) in comparison to SARS-CoV-2 (6.5 PFU/mL) using assay for S protein (n = 3). F) Exclusivity test on seasonal influenza virus A (H1N1) (10 2.9 TCID50 mL −1 ) and 2009 influenza virus pH1N1 (10 4.15 TCID50 mL −1 ) in comparison to SARS-CoV-2 (6.5 x 10 4 PFU/mL) using assay for N protein (n = 3). (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Article Snippet: The use of the high sensitive antibodies is one of the main task to develop high sensitive and selective analytical device, thus for the selection of antibodies, spectrophotometric ELISA was carried out to assess the reactivity of MAb and two different PAb (Sinobiological, Germany and ProSci, USA) towards two different S proteins namely SARS Coronavirus 2019 Spike Recombinant protein (1000–1200 aa) and Recombinant Spike protein SARS-CoV Spike protein, S1 subunit.

Techniques: Cell Culture, Concentration Assay

Journal: Biosensors & Bioelectronics

Article Title: Magnetic beads combined with carbon black-based screen-printed electrodes for COVID-19: A reliable and miniaturized electrochemical immunosensor for SARS-CoV-2 detection in saliva

doi: 10.1016/j.bios.2020.112686

Figure Lengend Snippet: Overview of biosensors for SARS-CoV-2 detection.

Article Snippet: The use of the high sensitive antibodies is one of the main task to develop high sensitive and selective analytical device, thus for the selection of antibodies, spectrophotometric ELISA was carried out to assess the reactivity of MAb and two different PAb (Sinobiological, Germany and ProSci, USA) towards two different S proteins namely SARS Coronavirus 2019 Spike Recombinant protein (1000–1200 aa) and Recombinant Spike protein SARS-CoV Spike protein, S1 subunit.

Techniques: CRISPR, Amplification, Reporter Assay, SPR Assay, Transduction, Fluorescence, Immunochromatographic Assay