PDCD4 and systemic lupus erythematosus: Although the mechanism whereby PDCD4 regulates IL-10 and other cytokines remain an area of active investigation (49, 50), other groups have demonstrated that the miR-21/PDCD4 axis represents a key target for immunoregulation in multiple contexts, namely in protecting from type 1 diabetes (51), as a target for the endogenous danger ligand decorin-1 (52) and in regulating T-cell activation and polarization in SLE (53).