TGFB1 and Miyoshi myopathy: Furthermore, TGF-β has been directly implicated in instances of immune dysregulation, such as the defective upregulation of CD80 on dendritic cells from the peripheral blood of MM patients (41) and the impaired proliferation of T-cells as a result of TGF-β produced by either MM cells or by BM mesenchymal stromal cells derived from MM patients (27, 42).