Percentage of CD4
T cells expressing interleukin-6 (IL-6) or IL-9. The upper panel shows the percentage (mean ± standard deviation) of CD4+ T cells expressing IL-6 (within total CD4+ T cells) and of total, CD4+, and CD8+ T cells producing IL-9 (within total T cells, CD4+ T cells, and total CD8+ T cells, respectively), after mononuclear cell (MNC) stimulation with phorbol myristate acetate (PMA) plus ionomycin in the absence of mesenchymal stromal cells (MSCs) (MNCs + PMA + ionomycin) or in co-culture with MSCs (MSCs + MNCs + PMA + ionomycin). The lower panel shows the percentage of inhibition induced by MSCs on the percentage of total, CD4+ and/or CD8+ T cells expressing IL-6 or IL-9. Statistically significant differences were considered when P <0.05 for Wilcoxon paired-sample test: *versus MSCs + MNCs + PMA + ionomycin.