Preliminary study on immunologic mechanism of chemokine receptor CXCR3 and its ligands involved in mouse fulminant hepatitis
Objective To investigate the role of the chemokine receptor CXCR3 and its ligands in the migration of lymphocytes and acute hepatic failure. Methods BALB/cJ mice (6-8 weeks, female) were intraperitoneally injected with 100 PFU mouse hepatitis virus-3(MHV-3). The proportions and numbers of T cells and NK cells in liver, spleen, and blood as well as the expression of CXCR3 in T cells, and NK cells post MHV-3 infection was analyzed by flow cytometry. The hepatic mRNA level of the CXCR3-associated chemokines(CXCL9 and CXCL10) was detected by real-time PCR. A transwell migration assay was used to assess the chemotactic effect of MHV-3-infected hepatocytes and CXCL10 on the splenic lymphocytes. Results Following MHV-3 infection, the number of hepatic NK cells and T cells and the frequencies of hepatic NK cells and T cells expressing CXCR3 increased markedly; however, in the spleen and peripheral blood, they both decreased significantly. Moreover, the hepatic mRNAs levels of CXCL9 and CXCL10 were significantly elevated post infection. The transwell migration assay demonstrated that MHV-3-infected hepatocytes have the capacity to attract and recruit the splenic NK cells and T cells, and CXCL10 plays a key role in lymphocyte mobilization from the spleen. Conclusion Interactions between CXCR3 and its ligands (CXCL9 and CXCL10),especially CXCL10 may play a key role in the recruitment of intrahepatic lymphocytes and subsequent necroinflammation and acute hepatic failure in MHV-3 infection. 
 
Key words: 
Chemokine;  CXCR3; CXCL10;  Fulminant hepatitis;  Natural killer cell