Journal: Vaccines

Article Title: Longitudinal Analyses after COVID-19 Recovery or Prolonged Infection Reveal Unique Immunological Signatures after Repeated Vaccinations

doi: 10.3390/vaccines10111815

Figure Lengend Snippet: Serum antibody features in COVID-19 patients during hospitalization: Graphs show serum anti-S-RBD IgM ( A ) and IgG ( B ) levels for each disease severity ( n = 9 patients/mild group; 10 patients/moderate I group; 9 patients/moderate II patients). Blue and red dots indicate admission and discharge, respectively; the duration of hospitalization is indicated at the bottom of each panel. Graphs show the correlation between anti-S-RBD IgM or IgG and neutralizing antibody titer ( C ) and age, as well as the change in the titer against the WT strain in patients infected with the WT and VOCs ( D ). Each dot denotes disease severity, and Spearman’s correlation coefficients are shown within the graph. Gray areas indicate a 95% confidence interval (CI) for the total. ( E ) Dot plot indicates the neutralizing potency against the WT strain by sex. Graphs show the serum-neutralizing antibody titer against WT ( F ), Kappa ( G ), and Delta ( H ) variants at each severity (moderate II is classified by the infected strains, n = 9 patients/mild group; 10 patients/moderate I group; 9 patients/WT-infected moderate II group; 8 patients/VOC-infected moderate II group). Statistical significances were determined using the Tukey–Kramer test and Welch’s t -test. All horizontal bars show mean values. Cross, deceased; #, long-term observed healthcare worker. * p < 0.05; *** p < 0.005; ns, not significant.

Article Snippet: Isolated PBMCs were incubated with His-tagged SARS-CoV-2 S-RBD recombinant protein (Cell Signaling Technology, Danvers, MA, USA) for 30 min on ice.

Techniques: Infection

Journal: Vaccines

Article Title: Longitudinal Analyses after COVID-19 Recovery or Prolonged Infection Reveal Unique Immunological Signatures after Repeated Vaccinations

doi: 10.3390/vaccines10111815

Figure Lengend Snippet: Longitudinal analyses of serum neutralizing antibody activities and PBMCs in a patient with high neutralizing potency: ( A ) Concentration of anti-S-RBD IgM and IgG in the serum of a healthcare worker (indicated by # in ) upon infection. ( B ) Fluctuation of each neutralizing antibody titer from onset to post-vaccination ( n = 1). ( C ) Representative FACS plots of cell population are shown in panels. The numbers indicate the positive rate of each cell population. Graphs show the absolute number of IgG + S-RBD + Bmems ( D ) and the frequency of lymphocyte ( E ), CD19 + CD27 + CD38 high , and IgG + Bmems (( F ); n = 1, 3–5 technical replicates). Black dots indicate technical replicates. Each number indicates the mean.

Article Snippet: Isolated PBMCs were incubated with His-tagged SARS-CoV-2 S-RBD recombinant protein (Cell Signaling Technology, Danvers, MA, USA) for 30 min on ice.

Techniques: Concentration Assay, Infection

Journal: Vaccines

Article Title: Longitudinal Analyses after COVID-19 Recovery or Prolonged Infection Reveal Unique Immunological Signatures after Repeated Vaccinations

doi: 10.3390/vaccines10111815

Figure Lengend Snippet: Affinity maturation of S-RBD-specific memory B-cells after vaccination: Pie charts show the distribution of heavy chain genes ( A ) and light chain genes ( B ) from onset to post-vaccination, comparing patients with the recovered individual ( n = 1) and a prolonged COVID-19 patient ( n = 1). The number in the inner circle indicates the number of sequenced clones. ( C ) Graphs show the number of somatic hypermutations in each antibody gene. Statistical significances were determined using Tukey–Kramer test. ( D ) Graphs show the distribution of CDR3 length in each antibody gene (heavy chains; n = 34–45 clones/recovered individual, 14 clones/prolonged COVID-19 patient; light chains; 18–66 clones/recovered individual, 15 clones/prolonged COVID-19 patient).

Article Snippet: Isolated PBMCs were incubated with His-tagged SARS-CoV-2 S-RBD recombinant protein (Cell Signaling Technology, Danvers, MA, USA) for 30 min on ice.

Techniques: Clone Assay

Journal: Frontiers in Immunology

Article Title: Single-Cell Immunogenomic Approach Identified SARS-CoV-2 Protective Immune Signatures in Asymptomatic Direct Contacts of COVID-19 Cases

doi: 10.3389/fimmu.2021.733539

Figure Lengend Snippet: Study approach and distinct antibody responses to SARS-CoV-2 along with neutralization assay. (A) Outline delineating the experimental workflow. (B) Box plots showing the anti-SARS-CoV-2 total, IgA, IgM, and IgG antibody proportions in serum samples from controls, symptomatic- and asymptomatic-infected individuals and in contacts (C) . Pie chart showing the overall immunoglobulin response across subject groups. (D) Box plot depicting the percent inhibition of neutralizing antibodies in an in vitro spike RBD-ACE2 interaction-based surrogate virus neutralization assay. Statistical comparisons were performed using unpaired Wilcoxon test. p-values are written against respective comparisons, where n = number of individuals; IgA, immunoglobulin A; IgM, immunoglobulin M; IgG, immunoglobulin G; control (n = 14), infected (n = 23), symptomatic (n = 10), asymptomatic (n = 13), and contact (n = 24).

Article Snippet: For IgA and IgM quantification, receptor binding domain (RBD) (SARS-CoV-2 spike RBD recombinant protein, mFc-Tag, CST # 41701S) antigen at a concentration of 200 ng/well was coated in a 96-well high binding microtiter plate (HIMEDIA-EP1) in 1× Tris-buffered saline (TBS) pH-7.4 for 2 h at 37°C.

Techniques: Neutralization, Infection, Inhibition, In Vitro

Journal: medRxiv

Article Title: SARS-CoV-2 specific immune-signature in direct contacts of COVID-19 cases protect them from contracting disease: A Retrospective Study

doi: 10.1101/2021.03.11.21253367

Figure Lengend Snippet: A , Box plots showing the anti-SARS-CoV-2 IgA, IgM and IgG antibody proportions in serum samples from control, infected and contact along with B , Serum cytokine levels in pg/ml (Eotaxin, G-CSF, IL-7, MIF and MIP 1-□) determined by bio plex. C , The area under the receiver-operating characteristic (ROC) curve of the cytokines having more than 0.8 AUC. D , Box plot depicting the percent inhibition of neutralizing antibodies in an in -vitro spike RBD-ACE2 interaction based Surrogate Virus Neutralization assay. Statistical comparisons were performed using unpaired Wilcoxon test, p-values are written against respective comparisons. Where, n = number of individuals, IgA-Immunoglobulin A, IgM-Immunoglobulin M and IgG-Immunoglobulin G, control (n-14), infected (n-23, Symptomatic n-10 and Asymptomatic n-13) and contact (n-24).

Article Snippet: For IgA and IgM quantification, RBD (SARS-CoV-2 spike RBD recombinant protein, mFc-Tag, CST # 41701S) antigen at a concentration of 200ng/well was coated in a 96-well high binding micro titre plate (HIMEDIA-EP1) in 1x TBS pH-7.4 for 2h at 37□.

Techniques: Infection, Inhibition, In Vitro, Neutralization