Fig. 3

Immunostimulatory effect of Dex on T lymphocytes in vitro. a The proportions of CD69⁺, CD137⁺, CD107a⁺, perforin⁺ and GzmB⁺ cells in CD4⁺ T subpopulations after 36 h of incubation with PBS or exosomes were assessed by flow cytometry. b Effects of Dex on activation biomarkers, degranulation activity, and cytotoxic mediators including perforin and GzmB in CD8⁺ T lymphocytes after 36 h of incubation. c The proliferative ability of CD4⁺ and CD8⁺ T lymphocytes was assessed by CFSE-based analysis after coculture with PBS or exosomes for 72 h. d, e T lymphocytes were pretreated with exosomes. After 36 h, the T cells were seeded in ELISPOT plates overnight. The secretion of TNF-α (d) or IFN-γ (e) secreted by activated T lymphocytes was assessed by ELISPOT assays. f T cells were cocultured with PBS or exosomes for 36 h. ELISA was carried out to measure the concentration of IL-2 (pg/ml) in the supernatant of the T cells. g The cytotoxic effects of T lymphocytes pretreated with exosomes for 36 h were tested by an LDH assay at different E:T ratios (12.5:1, 25:1, 50:1, and 100:1). BP210 or BP210-T315I cells were used as the target cells. Values are presented as the mean ± SD. *p < 0.05, **p < 0.01, ***p < 0.001 vs. the mock group