Fig. 3: Humoral response after BTI in PLWH.

A Quantification of anti-SARS-CoV-2 IgG antibodies after BTI in PLWH (n = 16, 4–6 weeks post-BTI). Scatter plots with medians are shown. Dotted lines demarcate ranges ( > 2000, 200–2000, 20–200 BAU/mL), to visualize patients with good, low, and non-seroconversion, respectively. The VOC-specific serology (IgG anti-nucleocapsid combined with anti-BA1 or -BA2) was detailed before and after BTI in PLWH stratified by immune status (INR vs. IR). Mann–Whitney test, two-tailed p-values < 0.05 (*), values < 0.01 (**), values < 0.001 (***), and <0.0001 (****). B Quantification of RBD, Spike, and Nucleocapsid-binding B cells in PLWH after vaccination and BTI. Left: Frequency of SARS-CoV-2 -binding B cells including Spike⁺ RBD⁺, Spike⁺ RBD^- or Nucleocapsid after the vaccine in HD (n = 11, 5–6 months post-Dose 2) vs. PLWH (n = 41, 4–5 months post-Dose 2) or natural infection in convalescent COVID-19 (n = 18, 1-month post-infection) or BTI in HD (n = 14, 4–6 weeks post-BTI). Mann–Whitney test, two-tailed p-values < 0.05 (*), values < 0.01 (**), values < 0.001 (***), and <0.0001 (****). Right: Longitudinal frequency of SARS-CoV-2 -binding B cells including Spike⁺ RBD⁺, Spike⁺ RBD^- or Nucleocapsid after BTI in PLWH (n = 16, 4–6 weeks post-BTI). Wilcoxon matched-pair signed rank test, with ** and *** denoting p < 0.01 and p < 0.001. C Peripheral detection of anti-RBD humoral immunity in PLWH. Correlation plots between the concentration of anti-RBD IgG (Log10 transformed BAU/mL) and the frequencies of SARS-CoV-2 RBD- or Spike-binding B cells in total B cells from peripheral blood of PLWH stratified by immune (CD4 count) and infection (BTI) status. Pearson correlations are indicated with * for p < 0.05 and ** for p < 0.01. D Anti-SARS-CoV-2 humoral signature of PLWH after vaccination (n = 41) and BTI (n = 16). Visualization by PCA of WT or VOC IgG anti-RBD serological concentration, anti-Spike, and anti-nucleocapsid. Ellipses were automatically generated to delineate PLWH based on Immune (INR vs. IR) and infection status (vaccination vs. BTI). E Phenotype of SARS-CoV-2 Spike-binding B cells in PLWH after vaccination (n = 41, 4–5 months post-Dose 2). Frequency of Spike- and RBD-binding B cells expressing CD21, CD24, CD27, CD38, CD71, IgD, IgG, or IgM after the second dose of the COVID-19 vaccine. Kruskal–Wallis test was used to compare the different groups with a p-value of * for p < 0.05. See also Supplementary Fig. 3.