Inhibition of COX-2 Ameliorates Murine Liver Schistosomiasis Japonica Through Splenic Cellular Immunoregulation
Abstract We have reported the positive association of cyclooxygenase 2 (COX-2)/prostaglandin E2 (PGE2) axis with liver fibrosis induced by Schistosoma japonicum (Sj) infection, and TLR4 signaling controlled this axis. However, how COX-2 regulated immune response during Sj infection is still unclear. Here we further studied the effect of COX-2 specific inhibitor-NS398 on liver granulomatous inflammation, fibrosis and explored the mechanisms via evaluating different immune cell during Sj infection.The results showed that NS398 significantly reduced the size of liver granuloma, spleen and mesenteric lymph node (MLN) and alleviated chronic granulomatous inflammation. Mechanically, it might be via decreasing the numbers of Sj-induced T helper type 1 (Th1), Th2, T follicular helper (Tfh), T follicular regulatory cells (Tfr) and germinal center B (GCB) cells to alleviate the liver inflammation and fibrosis. In addition, there were no difference of the numbers of macrophages, neutrophils, MDSCs,Th17 and total B cells in the spleen of the mice with or without NS-398 treatment. Our above data suggests that COX-2/PGE2 inhibition may represent a potential therapeutic approach to schistosomiasis japonica.