Fig. 2

PD-L1 expression on OE-MSC-Exos and mechanisms of OE-MSC-Exos on suppressing Tfh cell polarization. (a) Flow cytometry analysis of PD-L1 expression on the surface of OE-MSC-Exos. (b, c) Tfh cell polarization in the presence of OE-MSC-Exos or OE-MSC-Exos (siPD-L1) after 72 h analyzed by flow cytometry assay. Values represent means ± S.D. (n = 3). (d, e) The phosphorylation levels of PI3K and AKT in naïve T cells treated with OE-MSC-Exos or OE-MSC-Exos (siPD-L1) under Tfh polarization conditions. Values represent means ± S.D. (n = 3). *P < 0.05, **P < 0.01