miR-638/Fosb axis and its role in Treg differentiation and immune tolerance. (A) Bioinformatic analysis indicated that Fosb as a potential target of miR-638. (B) Luciferase reporter assay validating the direct interaction between miR-638 and Fosb. (C) q-PCR and western blotting analysis of Fosb expression in HEK293T cells treated with miR-638 mimics or inhibitors, showing inverse effects. (D) Representative images of flow cytometry and quantification analysis of FoxP3 + Tregs. n = 3 biological replicates per group. Data are expressed as the mean ± SD. *P < .05, **P < .01, ***P < .001.