Fig. 4

CD4⁺ T cell-mediated immune responses after stimulation in vitro. (A–I) Representative tSNE plots of flow cytometry for the HCs at before, post-D2 (7 days after D2), and post-D3 (7 days after D3). Using tSNE projection of CD4⁺ T cells for five HCs participants pooled, gates defining the indicated cell subsets and relative protein expression levels of IFNγ (A), TNFα (D), and IL21 (G) are shown. Black highlighted areas are with IFNγ⁺, TNFα⁺, and IL21⁺ cells. Representative gating strategies and scatterplots of IFNγ⁺ (B), TNFα⁺ (E), and IL21⁺ (H) cells within CD4⁺ T cells in KTRs (red) and HCs (black) at before, post-D2, and post-D3, measured by flow cytometry. Comparison of the frequency of IFNγ⁺ (C), TNFα⁺ (F), and IL21⁺ (I) cells in the two groups. Blue bars represent the medians. Data were analyzed using the Mann–Whitney U test (*P < 0.05, **P < 0.01, ***P < 0.001). NC, negative controls.