Journal: Cell Reports

Article Title: Structural analysis of receptor engagement and antigenic drift within the BA.2 spike protein

doi: 10.1016/j.celrep.2022.111964

Figure Lengend Snippet: Global prevalence and S protein mutations of the Omicron sub-lineages (A) Global prevalence of Omicron sub-lineages BA.1, BA.1.1, and BA.2 from November 2021 to March 2022. Only Omicron sub-lineages surpassing 1% global frequency are displayed. Sequence data were downloaded from the Global Initiative on Sharing All Influenza Data (GISAID) and graphed as weekly prevalence. (B) SARS-CoV-2 spike (S) protein amino acid sequence boxplots for the wild-type (D614G), BA.1/BA.1.1, and BA.2 Omicron sub-lineages. The BA.1.1 lineage is identical to BA.1 with the exception of an additional R346K mutation. NTD, N-terminal domain; RBD, receptor-binding domain; RBM, receptor-binding motif. (C) Cryo-EM-derived atomic model of the BA.2 S glycoprotein. Each S protein protomer is colored in different shades of blue. The locations of modeled amino acid mutations are shown as spheres on one protomer. BA.1-, BA.1.1-, and BA.2-specific mutations are colored in magenta, light magenta, and purple, respectively. Shared mutations across BA.1, BA.1.1, and BA.2 sub-lineages are colored in gray.

Article Snippet: BA.1 RBD , Sino Biological , Cat# 40592-V08H121.

Techniques: Sequencing, Mutagenesis, Binding Assay, Cryo-EM Sample Prep, Derivative Assay

Journal: Cell Reports

Article Title: Structural analysis of receptor engagement and antigenic drift within the BA.2 spike protein

doi: 10.1016/j.celrep.2022.111964

Figure Lengend Snippet: Binding affinity and cryo-EM structure of the Omicron BA.2 S protein-human ACE2 complex (A) Surface plasmon resonance experiments measuring dimeric human ACE2 (hACE2) binding to immobilized wild-type (WT), BA.1, and BA.2 RBDs, performed in technical triplicates. Summary data are shown at the top with representative surface plasmon resonance (SPR)-binding curves (colored solid line), and fitted 1:1 binding models (black dashed line) are shown on bottom. (B) As in (A) but measuring WT, BA.1, and BA.2 RBDs binding to immobilized dimeric hACE2, performed in at least technical quadruplicates. (C) As in (A) but measuring WT, BA.1, and BA.2 ectodomains binding to immobilized dimeric hACE2, performed in at least technical duplicates. The WT and BA.1 data in (C) were previously reported. Pairwise statistical significance test was performed using a one-way ANOVA test ( ∗ p ≤ 0.05; ∗∗ p ≤ 0.01; ∗∗∗ p ≤ 0.001; ∗∗∗∗ p ≤ 0.0001, ns, not significant). (D) Focus-refined cryo-EM density map and fitted atomic model of the BA.2 RBD in complex with hACE2 at 2.8 Å. (E) Aligned atomic models of hACE2 bound to BA.1 and BA.2 RBDs. The BA.1 RBD (PDB: 7T9L ) and complexed hACE2 atomic models are shown in magenta and dark blue, respectively. The BA.2 RBD and complexed hACE2 atomic models are shown in purple and light blue, respectively. (F) Atomic model of the BA.1 S protein-hACE2 complex, focused on residue S496. The hydrogen bonding interaction between BA.1 S protein residue S496 and hACE2 residue K353 is indicated by an orange dashed line. (G) As in (F) but for the BA.2 S protein-hACE2 complex, focused on residue G496.

Article Snippet: BA.1 RBD , Sino Biological , Cat# 40592-V08H121.

Techniques: Binding Assay, Cryo-EM Sample Prep, SPR Assay, Residue

Journal: Cell Reports

Article Title: Structural analysis of receptor engagement and antigenic drift within the BA.2 spike protein

doi: 10.1016/j.celrep.2022.111964

Figure Lengend Snippet: Cryo-EM structure of the Omicron BA.2 S protein-mouse ACE2 complex (A) Cryo-EM density map of BA.2 S protein in complex with mouse ACE2 at 2.5 Å. Mouse ACE2 is shown in green, and protomers of the BA.2 S protein are shown in shades of purple. (B) Focus-refined cryo-EM density map and fitted atomic model of the BA.2 RBD-mouse ACE2 (mACE2) complex at 2.7 Å. (C) Aligned atomic models of the BA.1 and BA.2 RBD-mACE2 complexes. The BA.1 RBD and complexed hACE2 atomic models are shown in magenta and dark green, respectively. The BA.2 RBD and complexed hACE2 atomic models are shown in purple and light green, respectively. (D) Atomic model of the BA.2 RBD-mACE2 complex, focused on residues Y501 and H505. (E) As in (D) but focused on residue R493. (F) Atomic model of the WT RBD-hACE2, focused on residues N501 and Y505. (G) As in (H) but focused on residue Q493. (H) Atomic model of mACE2 from the perspective of a binding RBD. Black labels are mACE2 residues, and gray labels denote the interacting residues in a bound RBD. Gold labels denote the interacting residues in a bound RBD that are mutated in the BA.1 and BA.2 Omicron sub-lineages.

Article Snippet: BA.1 RBD , Sino Biological , Cat# 40592-V08H121.

Techniques: Cryo-EM Sample Prep, Residue, Binding Assay

Journal: Cell Reports

Article Title: Structural analysis of receptor engagement and antigenic drift within the BA.2 spike protein

doi: 10.1016/j.celrep.2022.111964

Figure Lengend Snippet: Antigenic shift of the BA.2 S protein (A) Percentage of binding of monoclonal antibodies against the BA.1 and BA.2 S proteins relative to WT as assessed by ELISA, performed in technical triplicates. (B) Antibody epitopes with the side chains of contacted residues within the RBD or NTD shown and colored. BA.1- and BA.2-mutated residues are labeled within the antibody epitopes in magenta and purple, respectively, with shared mutations labeled in gray. (C) Alignment of WT, BA.1, and BA.2 RBDs, with shared, BA.1-specific, and BA.2-specific mutations labeled in gray, magenta, and purple, respectively. (D) Alignment of select patient-derived RBD-directed antibodies on the RBD. CB6, PDB: 7C01 ; REGN10933/REGN10987, PDB: 6XDG ; CV2-75, PDB: 7M31 ; CR3022, PDB: 6YLA . (E) Side-by side comparison of WT (PDB: 7KRS ), BA.1 (PDB: 7TNW ), and BA.2 NTDs with a focused view on the structural rearrangement of the 67–79 loop and N1 antigenic loop. (F) Alignment of deposited patient-derived NTD-directed antibody atomic models with PDB IDs listed in Table S2 . The labels of antibodies that make intermolecular contacts with the N1 and/or 67–79 loop are colored in orange and/or underlined in green, respectively. The NTD is shown in gray with its N1 loop highlighted in orange and the 67–79 loop in green. (G) Schematic and BA.2/BA.1 antibody-binding ratio for domain-enriched (ectodomain, NTD, or RBD) BA.1-convalescent polyclonal sera. Serum was pooled from 18 BA.1-convalescent patients (16 breakthrough cases and 2 infections in non-vaccinated patients) prior to incubation with either BA.1 ectodomain, NTD, or RBD to enrich domain-specific BA.1-convalescent antibodies. The samples were washed prior to quantification of IgG binding by ELISA and plotting of the BA.2/BA.1 ratio of domain-specific antibody binding. Data are derived from serum from 18 pooled BA.1-convalescent patients, and the ELISA assays were performed in technical duplicates.

Article Snippet: BA.1 RBD , Sino Biological , Cat# 40592-V08H121.

Techniques: Binding Assay, Enzyme-linked Immunosorbent Assay, Labeling, Derivative Assay, Comparison, Incubation

Journal: Cell Reports

Article Title: Structural analysis of receptor engagement and antigenic drift within the BA.2 spike protein

doi: 10.1016/j.celrep.2022.111964

Figure Lengend Snippet:

Article Snippet: BA.1 RBD , Sino Biological , Cat# 40592-V08H121.

Techniques: Recombinant, Software

Journal: iScience

Article Title: Controllable self-replicating RNA vaccine delivered intradermally elicits predominantly cellular immunity

doi: 10.1016/j.isci.2023.106335

Figure Lengend Snippet: c-srRNA vaccine elicits cellular immunity (A–C) Cellular immunity assessed by enzyme-linked immunospot (ELISpot) assays. A single dose or two doses of a placebo (PBO) or 5 μg, or 25 μg of EXG-5003 RNAs, prepared as naked RNAs without LNP or other transfection reagents and in lactated Ringer’s solution, were administered intradermally to BALB/c mice. To assess cellular immunity, an ELISPOT assay, which quantitates the number of cytokine-secreting cells, was performed on splenocytes isolated on Day 14 and Day 42. The splenocytes were stimulated for 24 h with pools of peptides: 9mer peptides for RBD of SARS-CoV-2 (original strain) or 15mer peptides for RBD of SARS-CoV-2 (original strain). Data are presented as mean (SD). (D) Cellular immunity was assessed by intracellular cytokine staining (ICS) and flow cytometry assays. The FACS-ICS assays were performed on splenocytes isolated on Day 42. MFI, mean fluorescence intensity; p, placebo; v, EXG-5003. Data are presented as mean ± SEM. Two-tailed unpaired t-test: ns (p > 0.05), ∗ (p ≤ 0.05), ∗∗ (p ≤ 0.01), ∗∗∗ (p ≤ 0.001), ∗∗∗∗ (p ≤ 0.0001). (E) Cellular immunity assessed by in vivo tumor cell elimination assays. A single EXG-5003 vaccination suppresses the growth of 4T1-LUC tumor cells carrying SARS-CoV-2 spike protein (4T1-LUC-Spike cells). Data are presented as mean (SD).

Article Snippet: On day 14 (second treatment), the mice were treated with an intradermal injection of a placebo (PBO: buffer only), 25 μg EXG-5003 (c-srRNA1 encoding RBD [original strain]), 25 μg of EXG-5003o (c-srRNA3 encoding RBD [omicron variant B.1.1.529 BA.1]), or 10 μg RBD protein (Sino Biological SARS-CoV-2) + adjuvant (AddaVax).

Techniques: Enzyme-linked Immunospot, Transfection, Isolation, Staining, Flow Cytometry, Fluorescence, Two Tailed Test, In Vivo

Journal: iScience

Article Title: Controllable self-replicating RNA vaccine delivered intradermally elicits predominantly cellular immunity

doi: 10.1016/j.isci.2023.106335

Figure Lengend Snippet: c-srRNA vaccines can prime the immune system for the subsequent induction of neutralizing antibodies against a variant antigen upon exposure to the variant antigen (A) A schematic diagram of experimental procedures. EXG-5003 RNAs were prepared as naked RNAs, without LNP or other transfection reagents, in lactated Ringer’s solution. (B–D) Groups of CD-1 outbred mice (N = 10) received one of three formulations by intradermal injection on Day 0 and Day 14 (black arrows): (B) a placebo (buffer only), (C) 5 μg of EXG-5003 RNA, or (D) 5 μg of EXG-5003 RNA in combination with an RNase inhibitor (3 units of RNasin Plus; Promega, Madison, WI). Subsequently, all mice received a recombinant RBD protein (Ala319-Phe541, with a C-terminal 6-His tag, NCBI accession number: YP_009724390.1, R&D Systems, Minneapolis, MN) by intradermal injection on Day 49 (open arrows). To assess humoral immunity, an enzyme-linked immunosorbent assay (ELISA), which quantitates the amount of immunoglobulin G (IgG) specific to a recombinant RBD protein (represented as the geometric mean of endpoint titer in triplicate), was performed on serum obtained from the mice on Day −3, Day 14, Day 28, Day 46, Day 56, and Day 63. Data are presented as mean (SD). (E) A schematic diagram of experimental procedures. On day −40, blood was drawn from female BALB/c mice for a plaque reduction neutralization test (PRNT). On day −36, these mice received an intradermal injection of EXG-5003 RNA, which was prepared as a naked RNA, without an LNP or transfection reagent. On day −22 (14 days after EXG-5003 vaccination), half of the mice were sacrificed to obtain splenocytes for ELISpot assays. On day 0, the remaining mice were intradermally injected with the spike protein of the SARS-CoV-2 delta variant (B.1.617.2: R&D Systems) mixed with adjuvant—AddaVax (Invivogen). On day 7 (7 days after the spike protein injection), blood was drawn for the PRNT assay. (F) The induction of cellular immunity against the RBD protein by a single intradermal administration of EXG-5003 RNA. The ELISpot assay shows the number of IFN-γ spot-forming cells (SFCs) in 1 × 10ˆ6 splenocytes from immunized mice restimulated by culturing in the presence or absence of a pool of 15mer peptides for RBD of SARS-CoV-2 (original strain). The number of SFC obtained in the presence of peptides was plotted on the graph after subtracting the number of SFC obtained in the absence of peptides (background). The average and standard deviation (error bars) of five mice (n = 5) are shown for each group. (G) The titer of serum antibodies that can neutralize (50%) the SARS-CoV-2 virus (delta variant B.1.617.2), measured by the PRNT assay. Exposure to the spike protein of the SARS-CoV-2 virus (delta variant B.1.617.2) induced neutralization antibodies against the delta variant of the SARS-CoV-2 virus only in mice vaccinated with EXG-5003, which encodes the RBD of SARS-CoV-2 (original strain). Data are presented as mean (SD).

Article Snippet: On day 14 (second treatment), the mice were treated with an intradermal injection of a placebo (PBO: buffer only), 25 μg EXG-5003 (c-srRNA1 encoding RBD [original strain]), 25 μg of EXG-5003o (c-srRNA3 encoding RBD [omicron variant B.1.1.529 BA.1]), or 10 μg RBD protein (Sino Biological SARS-CoV-2) + adjuvant (AddaVax).

Techniques: Variant Assay, Transfection, Injection, Recombinant, Enzyme-linked Immunosorbent Assay, Plaque Reduction Neutralization Test, Enzyme-linked Immunospot, Standard Deviation, Neutralization

Journal: iScience

Article Title: Controllable self-replicating RNA vaccine delivered intradermally elicits predominantly cellular immunity

doi: 10.1016/j.isci.2023.106335

Figure Lengend Snippet: Improvement of c-srRNA and its use as a booster vaccine to induce antibodies against an antigen, following earlier administration of the antigen protein (A) Comparison of srRNA and c-srRNAs for T cell-inducibility. A schematic diagram of experimental procedures. On day 0, mice were intradermally injected with either placebo (PBO, buffer only), srRNA0, c-srRNA1, or c-srRNA3. The srRNA0, c-srRNA1, and c-srRNA3 encode the same RBD of SARS-CoV-2 (original strain). On day 14, mice were sacrificed and splenocytes were isolated for ELISpot assays. (B) The ELISpot assay shows the number of IFN-γ spot-forming cells (SFCs) in 1 × 10ˆ6 splenocytes from immunized mice restimulated by culturing in the presence or absence of a pool of 15mer peptides for RBD of SARS-CoV-2 (original strain). The number of SFC obtained in the presence of peptides was plotted on the graph after subtracting the number of SFC obtained in the absence of peptides (background). The average and standard deviation (error bars) are shown for each group. Two-tailed unpaired t test: ns (p > 0.05), ∗ (p ≤ 0.05), ∗∗ (p ≤ 0.01), ∗∗∗∗ (p ≤ 0.0001). (C) Use of c-srRNA vaccine as a booster to induce antibodies against an antigen, following earlier administration of the antigen protein. A schematic diagram of experimental procedures. On day 0 (first treatment), female C57BL/6 mice were treated with an intradermal injection of 10 μg RBD protein (Sino Biological SARS-CoV-2 [original strain]) + adjuvant (AddaVax). On day 14 (second treatment), the mice were treated with an intradermal injection of a placebo (PBO: buffer only), 25 μg EXG-5003 (c-srRNA1 encoding RBD [original strain]), 25 μg of EXG-5003o (c-srRNA3 encoding RBD [omicron variant B.1.1.529 BA.1]), or 10 μg RBD protein (Sino Biological SARS-CoV-2) + adjuvant (AddaVax). On day 28, the mice were sacrificed, and splenocytes and serum were collected for ELISpot and ELISA assays. (D) The induction of cellular immunity is shown by the frequency of IFN-γ spot-forming cells (SFC) in 1 × 10ˆ6 splenocytes restimulated by culturing in the presence or absence of a pool of 15mer peptides for RBD of SARS-CoV-2 (original strain) (RBD-PBO, RBD-EXG-5003, RBD-RBD) or 15mer peptides for RBD of SARS-CoV-2 (omicron variant) (RBD-EXG-5003o). The frequency obtained in the presence of peptides is plotted in the graph after subtracting the frequency obtained in the absence of peptides (background). Data are represented as mean (SD). (E) The levels of serum antibodies against the RBD protein of the SARS-CoV-2 (original strain), measured by an ELISA assay. The levels of antibodies are represented by the OD450 measurement. The average and standard deviation (error bars) of five mice (n = 5) are shown for each group. The data from Day −1 (before the first treatment) and the data from Day 28 (after the second treatment) are shown for each group. Data are represented as mean (SD).

Article Snippet: On day 14 (second treatment), the mice were treated with an intradermal injection of a placebo (PBO: buffer only), 25 μg EXG-5003 (c-srRNA1 encoding RBD [original strain]), 25 μg of EXG-5003o (c-srRNA3 encoding RBD [omicron variant B.1.1.529 BA.1]), or 10 μg RBD protein (Sino Biological SARS-CoV-2) + adjuvant (AddaVax).

Techniques: Injection, Isolation, Enzyme-linked Immunospot, Standard Deviation, Two Tailed Test, Variant Assay, Enzyme-linked Immunosorbent Assay

Journal: iScience

Article Title: Controllable self-replicating RNA vaccine delivered intradermally elicits predominantly cellular immunity

doi: 10.1016/j.isci.2023.106335

Figure Lengend Snippet: Generation of EXG-5008, encoding RBD and nucleoproteins of SARS-CoV-2 and MERS (A) A schematic diagram of EXG-5008, encoding a fusion protein of the signal peptide of CD5, the RBD and nucleoprotein of SARS-CoV-2, and the RBD and nucleoprotein of MERS-CoV. (B and C) The frequency of IFN-γ spot-forming cells (B) and the frequency of IL-4 spot-forming cells (C) in 1 × 10ˆ6 splenocytes obtained from female C57BL/6 mice that were immunized by a single intradermal injection of 100 μL solution containing either placebo (PBO: buffer only), 25 μg of EXG-5006a, or 25 μg of EXG-5008. The splenocytes were restimulated by culturing in the presence or absence of pools of peptides: 15mer peptides for RBD of SARS-CoV-2 (original strain) ( 1 ); 15mer peptides for nucleoprotein of SARS-CoV-2 (original strain) ( 2 ); 15mer peptides for nucleoprotein of MERS-CoV ( 3 ); 15mer peptides for the spike of MERS-CoV ( 4 ). The cellular immunity was analyzed by ELISpot assays. The frequency obtained in the presence of peptides is plotted in the graph after subtracting the frequency obtained in the absence of peptides (background). The average and standard deviation (error bars) of five mice (n = 5) for PBO, four mice (n = 4) for EXG-5006, and five mice (n = 5) for EXG-5008, are shown for each group. Splenocytes were isolated 14 days after vaccination. (D) A model showing how the c-srRNA booster vaccine works. Primary series of vaccines or prior infections expose naive B cells to viral surface proteins and turn them into memory B cells in a manner dependent on CD4 + helper T cells. Skin delivery of a c-srRNA booster vaccine encoding a fusion antigen of the viral surface proteins and internal proteins, whose sequences are more evolutionarily conserved than the surface proteins, is primarily incorporated into skin antigen-presenting cells such as Langerhans cells and dendritic cells. Within the antigen-presenting cells, c-srRNA replicates and produces the fusion antigen. The antigen-presenting cells digest the antigen into peptides and present these peptides to T cells. The peptides presented through this pathway stimulate MHC-I-restricted CD8 + cytotoxic T cells as well as MHC-II-restricted CD4 + helper T cells. CD8 + cytotoxic T cells eliminate infected cells (B) CD4 + helper T cells stimulate the memory B cells and enhance or restore the production of neutralizing antibody, which prevents infection.

Article Snippet: On day 14 (second treatment), the mice were treated with an intradermal injection of a placebo (PBO: buffer only), 25 μg EXG-5003 (c-srRNA1 encoding RBD [original strain]), 25 μg of EXG-5003o (c-srRNA3 encoding RBD [omicron variant B.1.1.529 BA.1]), or 10 μg RBD protein (Sino Biological SARS-CoV-2) + adjuvant (AddaVax).

Techniques: Injection, Enzyme-linked Immunospot, Standard Deviation, Isolation, Infection

Journal: iScience

Article Title: Controllable self-replicating RNA vaccine delivered intradermally elicits predominantly cellular immunity

doi: 10.1016/j.isci.2023.106335

Figure Lengend Snippet:

Article Snippet: On day 14 (second treatment), the mice were treated with an intradermal injection of a placebo (PBO: buffer only), 25 μg EXG-5003 (c-srRNA1 encoding RBD [original strain]), 25 μg of EXG-5003o (c-srRNA3 encoding RBD [omicron variant B.1.1.529 BA.1]), or 10 μg RBD protein (Sino Biological SARS-CoV-2) + adjuvant (AddaVax).

Techniques: Recombinant, Modification, Derivative Assay, Variant Assay, Plasmid Preparation, Enzyme-linked Immunospot, Double-Color Enzymatic ELISPOT, Enzyme-linked Immunosorbent Assay, Plaque Reduction Neutralization Test, Software, Imaging

Journal: Scientific Reports

Article Title: Functional antibody responses targeting the Spike protein of SARS-CoV-2 Omicron XBB.1.5 in elderly nursing home residents following Wuhan-Hu-1-based mRNA booster vaccination

doi: 10.1038/s41598-024-62874-7

Figure Lengend Snippet: Neutralizing antibody titres (reciprocal IC 50 ) against the spike protein of Wuhan-Hu-1 ( A ), Omicron BA.4/5 ( B ), and Omicron XBB.1.5 ( C ) in elderly nursing home residents before and after one (pre-3D and post-3D, respectively) or two (pre-4D and post-4D, respectively) COVID-19 vaccine booster doses. The number of plasma samples analysed at the different sampling times is shown. Bars indicate medians and IQRs. P values for differences are shown.

Article Snippet: Briefly, purified, recombinant S proteins, corresponding to the SARS-CoV-2 Spike S1 + S2 trimer protein of either the D614G or Omicron XBB.1.5 variants (SinoBiological, Eschborn, Germany), were plated overnight in Thermo NUNC MaxiSorp 96-well plates at 3 μg/ml in borate buffered saline at 4ºC.

Techniques: Sampling

Journal: Scientific Reports

Article Title: Functional antibody responses targeting the Spike protein of SARS-CoV-2 Omicron XBB.1.5 in elderly nursing home residents following Wuhan-Hu-1-based mRNA booster vaccination

doi: 10.1038/s41598-024-62874-7

Figure Lengend Snippet: Neutralizing antibody titres (reciprocal IC 50 ) against the spike protein of Wuhan-Hu-1, Omicron BA.4/5 , and Omicron XBB.1.5 in elderly nursing home residents before and after one (pre-3D and post-3D, respectively) or two (pre-4D and post-4D, respectively) COVID-19 vaccine booster doses, according to their SARS-CoV-2 infection status (experienced/Vac-ex or naïve/Vac-n). The number of plasma samples analysed at the different sampling times is shown. Bars indicate medians and IQRs. P values for differences are shown.

Article Snippet: Briefly, purified, recombinant S proteins, corresponding to the SARS-CoV-2 Spike S1 + S2 trimer protein of either the D614G or Omicron XBB.1.5 variants (SinoBiological, Eschborn, Germany), were plated overnight in Thermo NUNC MaxiSorp 96-well plates at 3 μg/ml in borate buffered saline at 4ºC.

Techniques: Infection, Sampling

Journal: Scientific Reports

Article Title: Functional antibody responses targeting the Spike protein of SARS-CoV-2 Omicron XBB.1.5 in elderly nursing home residents following Wuhan-Hu-1-based mRNA booster vaccination

doi: 10.1038/s41598-024-62874-7

Figure Lengend Snippet: Comparison of antibody-dependent NK cell-mediated responses against SARS-CoV-2 Wuhan-Hu-1 and Omicron XBB.1.5 spike variants in elderly nursing home residents before and after one (pre-3D and post-3D, respectively) or two (pre-4D and post-4D, respectively) COVID-19 vaccine booster doses. Frequencies of LAMP1- (lysosomal-associated membrane protein 1) and IFN (interferon) γ-producing NK cells are shown in panels A and B, respectively. The number of participants analysed at the different sampling times is shown. Bars indicate medians and IQRs. P values for differences are shown.

Article Snippet: Briefly, purified, recombinant S proteins, corresponding to the SARS-CoV-2 Spike S1 + S2 trimer protein of either the D614G or Omicron XBB.1.5 variants (SinoBiological, Eschborn, Germany), were plated overnight in Thermo NUNC MaxiSorp 96-well plates at 3 μg/ml in borate buffered saline at 4ºC.

Techniques: Comparison, Membrane, Sampling

Journal: Scientific Reports

Article Title: Functional antibody responses targeting the Spike protein of SARS-CoV-2 Omicron XBB.1.5 in elderly nursing home residents following Wuhan-Hu-1-based mRNA booster vaccination

doi: 10.1038/s41598-024-62874-7

Figure Lengend Snippet: Impact of COVID-19 booster vaccination on antibody-dependent NK cell-mediated responses against SARS-CoV-2 Wuhan-Hu-1 and Omicron XBB.1.5 spike variants in elderly nursing home residents. The frequencies of LAMP1 (lysosomal-associated membrane protein 1)-producing NK cells against Wuhan-Hu-1 and Omicron XBB.1.5 are shown in ( A ) and ( B ), respectively. The frequencies of IFN (interferon) γ-producing NK cells against Wuhan-Hu-1 and Omicron XBB.1.5 are shown in ( C ) and ( D ), respectively. The number of participants analysed at the different sampling times is shown. Bars indicate medians and IQRs. P values for differences are shown.

Article Snippet: Briefly, purified, recombinant S proteins, corresponding to the SARS-CoV-2 Spike S1 + S2 trimer protein of either the D614G or Omicron XBB.1.5 variants (SinoBiological, Eschborn, Germany), were plated overnight in Thermo NUNC MaxiSorp 96-well plates at 3 μg/ml in borate buffered saline at 4ºC.

Techniques: Membrane, Sampling

Journal: Scientific Reports

Article Title: Functional antibody responses targeting the Spike protein of SARS-CoV-2 Omicron XBB.1.5 in elderly nursing home residents following Wuhan-Hu-1-based mRNA booster vaccination

doi: 10.1038/s41598-024-62874-7

Figure Lengend Snippet: Antibody-dependent NK cell-mediated responses against SARS-CoV-2 Wuhan-Hu-1 and Omicron XBB.1.5 spike variants in elderly nursing home residents according to their SARS-CoV-2 infection status (experienced/Vac-ex or naïve/Vac-n). The frequencies of LAMP1- (lysosomal-associated membrane protein 1)-producing NK cells against Wuhan-Hu-1 and Omicron XBB.1.5 at the different testing times are shown in ( A ) and ( B ), respectively. The frequencies of IFN (interferon)γ-producing NK cells against Wuhan-Hu-1 and Omicron XBB.1.5 are shown in ( C ) and ( D ), respectively. The number of participants analysed at the different sampling times is shown. Bars indicate medians and IQRs. P values for differences are shown.

Article Snippet: Briefly, purified, recombinant S proteins, corresponding to the SARS-CoV-2 Spike S1 + S2 trimer protein of either the D614G or Omicron XBB.1.5 variants (SinoBiological, Eschborn, Germany), were plated overnight in Thermo NUNC MaxiSorp 96-well plates at 3 μg/ml in borate buffered saline at 4ºC.

Techniques: Infection, Membrane, Sampling

Journal: Scientific Reports

Article Title: Functional antibody responses targeting the Spike protein of SARS-CoV-2 Omicron XBB.1.5 in elderly nursing home residents following Wuhan-Hu-1-based mRNA booster vaccination

doi: 10.1038/s41598-024-62874-7

Figure Lengend Snippet: Correlation between Neutralizing antibody (NtAb) levels and frequencies of LAMP1- (lysosomal-associated membrane protein 1)-producing or (interferon)γ-producing NK cells against Wuhan-Hu-1 ( A and B , respectively) and Omicron XBB.1.5 ( C and D , respectively). Rho and P values by the Spearman Rank test are shown.

Article Snippet: Briefly, purified, recombinant S proteins, corresponding to the SARS-CoV-2 Spike S1 + S2 trimer protein of either the D614G or Omicron XBB.1.5 variants (SinoBiological, Eschborn, Germany), were plated overnight in Thermo NUNC MaxiSorp 96-well plates at 3 μg/ml in borate buffered saline at 4ºC.

Techniques: Membrane