Fig. 9: Tregs treated with SAR’336 are potent suppressors of CD8 + T cell proliferation ex vivo.

a Schematic of the experiment to measure ex vivo suppressive capacity of Tregs: mice were administered either vehicle or SAR’336 (0.3 mg/kg), and splenocyte populations were collected at 2 days post-dose. The CD4+ Treg cells were isolated from the splenocytes derived from dosed and naïve animals. Next, CD4 or CD8 + T cells were harvested from splenocytes from naïve or vehicle-treated animals. To measure ex vivo suppressive capacity, Tregs were co-cultured at different ratios with CD4 or CD8 + T cells from naïve or vehicle-treated animals. After 3 days of co-culture, the (b) CD4 + T cells and (c) CD8 + T cell populations from each condition were analyzed for proliferation using thymidine incorporation (b) or flow cytometry (c); [mean ± SD]. d CD8 + T cells and Tregs were sorted from freshly isolated PBMC and cultured 4 days with recombinant IL-2 or SAR’336. Proliferation of CD8 T cells is reported. N = 2 donors pooled from independent experiments. Symbols represent individual donors. Lines represent mean response. CD4 cluster of differentiation 4, CD8 cluster of differentiation 8, CTV CellTrace Violet™ (dye), conv conventional T cell, Treg regulatory T cell. Mouse vector illustration credit: [baluchis]/stock.adobe.com.