In Experimental and Molecular Pathology, researchers in China and the US report that IL-21R expression on CD8+ T-cells promotes their activation in coxsackievirus B3-induced myocarditis. The team infected C57Bl/6 and IL-21R knock-out mice with CVB3 and found that the IL-21RKO mice developed significantly less myocarditis than C57Bl/6 animals. "Numbers of CD8+IFNγ+ cells were decreased in IL-21RKO mice but numbers of either CD4+IFNγ+ or CD4+IL-4+ cells were not significantly different from C57Bl/6 animals indicating a selective effect of IL-21 signaling on the CD8+ T cell response," the authors write. This, they add, suggests that IL-21 signaling directly in CD8+ T-cells in required for CVB3-induced myocarditis.
Also in Experimental and Molecular Pathology this week, researchers in New York report that the drug sirolimus modulates the HIV-associated nephropathy phenotype by inhibiting epithelial mesenchymal transition. In its study, the team observed the effects of sirolimus on the development of renal cell EMT and on HIVAN in a mouse model of HIVAN. The HIVAN mice that received saline showed enhanced proliferation of both glomerular and tubular cells compared to control mice that also received saline, the team says. However, HIVAN mice receiving sirolimus showed attenuated renal cell proliferation compared to HIVAN mice receiving saline. "Since sirolimus attenuated renal cell ZEB expression (a repressor of E-cadherin transcription), it appears that sirolimus may be attenuating renal cell EMT by preserving epithelial cell E-cadherin expression," the authors add.