IFNG and myelodysplastic syndrome: In addition, some MSCs of HR-MDS (Yin) can promote the pro-inflammatory cytokines such as TNF-α and IFN-γ secretion (Yang) which induce the increase of PD-L1/2 synthesis and secretion, and finally inhibit the activation and proliferation of CD4+T cells and promote the apoptosis of T cells (Yin) (43).