sars-cov-2 omicron (b.1.1.529) variant spike rbd elisa kit  (Sino Biological)

Journal: mBio

Article Title: Re-infection with SARS-CoV-2 is associated with increased antibody breadth and potency against diverse sarbecovirus strains

doi: 10.1128/mbio.03612-25

Figure Lengend Snippet: Functional activity of PVI-2 antibodies compared to PVI-1 antibodies from the same clonal family. ( A ) Percent somatic hypermutation of IgG heavy chain and light chain among clonal lineage members. ( B ) Comparison of binding profiles between PVI-1 mAbs and clonal lineage members in PVI-2. The heatmap shows OD450 nm binding activity by ELISA, with the antigens tested shown to the left. The antibodies tested are indicated at the top with mAbs from PVI-1 in orange text and PVI-2 in black text. mAbs were tested in duplicate at a fixed concentration of 1,000 ng/mL. Green indicates binding with increasing shades of green indicating increasing OD450 values, as indicated in the key to the right. The cases with the darkest green (>3.0 OD450) are qualitative and not quantitative results, as the assay would be saturated for the most potent binding mAbs. Gray indicates no detectable binding. ( C ) Heatmap of neutralization IC50s (µg/mL) of the same antibodies as in panel B. Viruses tested are shown to the left, with SARS-CoV-2 variants in the top half and more diverse sarbecoviruses in the bottom half. The color gradient represents neutralization activity as shown in the key to the right, with darker shades of blue correlating with IC50 potency. Gray indicates no detectable neutralization (IC50), and white indicates the mAbs were not tested because they did not bind SARS-CoV-1 spike trimer. IC50 values were averaged from 2 to 6 independent experiments performed in technical duplicate. IC50 values were calculated with GraphPad Prism, with a four-parameter non-linear regression model. ( D ) Geometric mean of the IC50 values (µg/mL) and 95% confidence intervals (CI) of the panel of viruses tested in panel C . IC50 >20 µg/mL was set to 20 µg/mL in this calculation. The number of viruses neutralized is displayed as a fraction of viruses that the antibody neutralizes with an IC50 <20 µg/mL, over the total number of viruses the antibody was tested against.

Article Snippet: In addition, a subset was also tested for binding to SARS-CoV-2 Delta trimer (Sino Biological, cat. 40589-V08H10) and SARS-CoV-2 B.Q.1.1 trimer (Sino Biological, cat. 40589-V08H41).

Techniques: Functional Assay, Activity Assay, Comparison, Binding Assay, Enzyme-linked Immunosorbent Assay, Concentration Assay, Neutralization

Journal: mBio

Article Title: Re-infection with SARS-CoV-2 is associated with increased antibody breadth and potency against diverse sarbecovirus strains

doi: 10.1128/mbio.03612-25

Figure Lengend Snippet: Binding and neutralization of antibodies representing new clonal lineages specific to PVI-2. ( A ) Heatmap shows binding (green) and neutralization IC50s (blue, last two columns). Viruses tested are shown at the top, and mAbs are indicated to the left, after the clonal family designation. IC50 values were averaged from two independent experiments performed in technical duplicate. Figure details are as described in . ( B ) Comparison of IC50s for SARS-CoV-2 XBB1.5 and SARS-CoV-1 for antibodies from PVI-2 specific clonal lineages. The P value is calculated from the Wilcoxon matched-paired signed rank test. Antibodies with no neutralization activity (IC50 > 20 µg/mL) were set to 20 µg/mL for this comparison.

Article Snippet: In addition, a subset was also tested for binding to SARS-CoV-2 Delta trimer (Sino Biological, cat. 40589-V08H10) and SARS-CoV-2 B.Q.1.1 trimer (Sino Biological, cat. 40589-V08H41).

Techniques: Binding Assay, Neutralization, Comparison, Activity Assay

Journal: mBio

Article Title: Re-infection with SARS-CoV-2 is associated with increased antibody breadth and potency against diverse sarbecovirus strains

doi: 10.1128/mbio.03612-25

Figure Lengend Snippet: Functional characterization of a pan-sarbecovirus neutralizing antibody C68.490. ( A ) Binding breadth of C68.490 and previously characterized antibodies with known pan-sarbecovirus activity against a library of yeast-display sarbecovirus RBDs. Antibodies tested are shown to the left with the specific RBD indicated at the bottom. RBDs are classified by clades as shown above and color-coded. Data for VIR-7229, SA55, and S2X259 were previously published by reference and shown for comparison. ( B ) Comparison of C68.490 binding with other pan-sarbecovirus antibodies by sarbecovirus clade. Statistically significant differences in mean EC50 values between C68.490 and other antibodies were assessed using the Friedman test with Dunn’s multiple comparisons test. Sarbecovirus RBDs were assigned to clades based on existing clade definitions . ( C ) Neutralization of SARS-CoV-2 and sarbecovirus variants by C68.490. Antibodies tested are described at the top and include two control mAbs for comparison. The viruses tested are shown to the left, with a line separating SARS-CoV-2 variants from the more diverse sarbecoviruses. Neutralization data are represented as IC50s (µg/mL) and color-coded as shown in the table below. IC50 values were averaged from 2 to 4 independent experiments performed in technical duplicate, with the exception of neutralization of S2X259 against SARS-CoV-1, which was only tested once. Data for C68.61, which was tested in parallel to the C68.490, was also reported in reference . Other details are as in .

Article Snippet: In addition, a subset was also tested for binding to SARS-CoV-2 Delta trimer (Sino Biological, cat. 40589-V08H10) and SARS-CoV-2 B.Q.1.1 trimer (Sino Biological, cat. 40589-V08H41).

Techniques: Functional Assay, Binding Assay, Activity Assay, Comparison, Neutralization, Control

Journal: mBio

Article Title: Re-infection with SARS-CoV-2 is associated with increased antibody breadth and potency against diverse sarbecovirus strains

doi: 10.1128/mbio.03612-25

Figure Lengend Snippet: Characterization of C68.490 escape mutations. ( A ) Top, sites of binding escape and residues conferring escape from C68.490 in different viral backgrounds (WH1 = SARS-CoV-2 Wuhan-Hu-1, BA.2 = SARS-CoV-2 Omicron BA.2, SARS1 = SARS-CoV-1 Urbani) by deep mutational scanning of the RBD. Amino acid numbering based on the SARS-CoV-2 WH1 sequence. Bottom, sites of escape mapped onto surface representation of the RBD (key interacting motifs of ACE2 shown as the gray ribbon). Color gradient represents the escape fraction, with darker red encompassing degree of escape. ( B ) Multi-clade sarbecovirus sequence alignments. Conserved sites (in blue) and variable residues (in white) across sarbecoviruses around the epitope of C68.490 defined in panel A are depicted. C68.490 sites of escape are indicated with yellow arrows. ( C ) Genotype at SARS-CoV-2 spike amino acid sites 378 and 384 from 2,967 GenBank sequences. Adapted from Nextstrain.org (retrieved 16 November 2025).

Article Snippet: In addition, a subset was also tested for binding to SARS-CoV-2 Delta trimer (Sino Biological, cat. 40589-V08H10) and SARS-CoV-2 B.Q.1.1 trimer (Sino Biological, cat. 40589-V08H41).

Techniques: Binding Assay, Sequencing