Fig. 2: Enhancement of the T cell response to COVID-19 vaccines in BCD participants with MS.

S-reactive T cells were identified following stimulation with S peptide pools using the activation-induced marker (AIM) assay (see methods). Representative flow cytometry plots of CD4⁺ (a) and CD8⁺ (b) T cells (see gating strategy Supplementary Fig. 1a) expressing activation markers after control DMSO stimulation (top) or S peptide stimulation (bottom) in non-BCD (left) or BCD (right) participants. S-reactive CD4⁺ (c) and CD8⁺ (d) T cells in non-BCD (black) vs BCD (red) participants (left) and BCD participants taking OCR (dark red), RTX (red), and OFA (pink) (right) shown as a percentage of non-naïve T cells in each site. e S-reactive CD4⁺T cells over time post-vaccination for non-BCD (black, left) and BCD (red, right) participants. f Same as (e) for CD8⁺T cells. Statistics: (c–d) Bar plots represent data as mean ± standard deviation and a one-way analysis of covariance (ANCOVA) was used to evaluate the difference in quantities of S-reactive T cells between cohorts after controlling for age, sex, vaccine type, and time-post vaccination. e–f A linear model was used to investigate the relationship between S-reactive T cell frequency and time post-vaccination controlling for age, sex, and vaccine-type. **p < 0.01, *p < 0.05, ns p ≥ 0.05 Abbreviations: BCD (B cell depleting/depleted), non-BCD (non B cell depleting/depleted), OCR (Ocrelizumab), RTX (Rituximab), OFA (Ofatumumab), S (Spike protein).