Fig. 1

PPARγ agonists promote the generation and function of Treg cells. a–d The cells isolated from mesenteric lymph nodes of mice were cultured with rosiglitazone (0, 1, 3, 10, 30, 100 μM), 15d-PGJ2 (0, 1, 3, 10, 30, 100 μM) and morin (0, 1, 3, 10, 30, 100 μM). Cell viability was analyzed by MTT and CCK-8 assay after 72 h, and the mRNA expression of LPL was measured by Q-PCR after 24 h. e–g The naïve CD4⁺ T cells were prepared and treated with anti-CD3/CD28 in the presence or absence of TGF-β (5 ng/mL), rosiglitazone (10, 30 μM), 15d-PGJ2 (3, 10 μM) as well as morin (10, 30 μM) for 72 h. The frequency of CD4⁺Foxp3⁺ T cells was examined by flow cytometry (e), the protein level of Foxp3 was detected by western blotting (f), and the mRNA expression levels of IL-10, CTLA4 and TIGIT were measured by Q-PCR (g). h The naïve CD4⁺ T cells were stimulated under Treg differentiation conditions for 72 h, and then treated with anti-CD3/CD28 in the presence or absence of rosiglitazone (30 μM), 15d-PGJ2 (10 μM) as well as morin (30 μM) for another 72 h. The mRNA expression levels of IL-10, CTLA4 and TIGIT were measured by Q-PCR. i The naïve CD4⁺ T cells were stimulated under Treg differentiation conditions for 72 h, and then co-cultured with CFSE-labeled CD4⁺ T cells under the stimulation of anti-CD3/CD28 in the presence or absence of rosiglitazone (30 μM), 15d-PGJ2 (10 μM) as well as morin (30 μM) for another 72 h. The suppressive activity of Treg cells were examined by flow cytometry. j The naïve CD4⁺ T cells were prepared and treated with anti-CD3/CD28 in the presence or absence of TGF-β (5 ng/mL), rosiglitazone (10, 30 μM), 15d-PGJ2 (3, 10 μM) as well as morin (10, 30 μM) for 72 h. The mRNA expression level of Foxp3 was measured by Q-PCR. k, l The naïve CD4⁺ T cells were prepared and treated with anti-CD3/CD28 in the presence or absence of TGF-β (5 ng/mL), actinomycin D (Act-D; 1 μM), rosiglitazone (30 μM), 15d-PGJ2 (10 μM) as well as morin (30 μM) for 72 h. The mRNA expression level of Foxp3 was measured by Q-PCR (k), and the protein level of Foxp3 was detected by western blotting (l). Data were presented as the means ± S.E.M. of three independent experiments (n = 3). ^#P < 0.05, ^##P < 0.01 versus control group; *P < 0.05, **P < 0.01 versus TGF-β group (model group); ^$$P < 0.01 versus rosiglitazone group; ^&&P < 0.01 versus 15d-PGJ2 group; ^††P < 0.01 versus morin group