Fig. 2

Negative association between MAIT cell activation markers and vaccine responses. Uniform Manifold Approximation and Projection (UMAP) plots of the total MAIT cell pool with overlay color indicating data from high or low spike-specific CD4 T cell responses (A, left) or S-antibody titer (B, left) and showing MAIT cell expression of the activation marker CD69 (A, right; B, right). Concatenated flow cytometry plots (C) and combined data (D) of MAIT cell CD69 expression (n = 36–42) at the different time points in the healthy donor group. Correlation of the percentage of CD40L+CD69+CD4 T cells at day 35 (n = 42) with the percentage of CD69 + MAIT cells at day 0 (n = 42) (E) or day 35 (n = 42) (F). G Correlation between the S-antibody titer at day 35 (n = 41) and expression of CD69 on MAIT cells at day 35 (n = 42). Concatenated flow cytometry plot (H) and combined data (I) of MAIT cell CD38 expression (n = 36–42) at the different time points in the healthy donor group. J Correlation between the S-antibody titer at day 35 (n = 42) and the CD38 expression on MAIT cells at day 0 (n = 42). Associations were assessed using the Spearman rank correlation in E–G and J