TGFB1 and plasma cell myeloma: MSCs in the myeloma BMME suppress T cell activation and proliferation, impair DC maturation, and induce Tregs via the secretion of several cytokines and interleukins such as IL-6, TGF-β, IL-10, and upregulation of surface molecules such as VCAM-1, ICAM-1, or CD40 [14,24,25].