Immune regulatory effect of natural killer T cells in the early stage of murine liver injury induced by type 5 adenovirus / 中华微生物学和免疫学杂志

ABSTRACT

Objective To study the immune regulatory effect of natural killer cell(NKT) in the early stage of murine liver injury induced by type 5 adenovirus(Ad5). Methods Animal models were con-structed by injected C57BL/6 mice with 1.5×109-3×109 PFU Ad5 into the tail vein. Liver injury of mouse at day 0, 1, 2, 3, 4, 5 after infection was determined by HE staining and serum ALT/AST(alanine amin-otransferase/aspartate aminotransferase) level. Flow cytometry analysis was used to measure the proportion of lymphocytes, expression of Fas/FasL on the surface of NKT cells and level of IL-4, IFN-γ/in NKT cell plasma in the infected mouse liver. RT-PCR was applied to semi-quantify the chemokines and their receptors mRNA in infected mouse liver. Results NKT cells of mouse increased significantly at day 1 after infected with high titer Ads(3×109 PFU), expression of FasL on NKT cell and plasma IL-4, IFN-γ/level in NKT cells were also up-regulated, hence the obviously infiltration of lymphocytes in routine liver. Comparing with high titer Ads infection, low titer Ads infection (1.5×109 PFU) lead to little change of NKT cell proper-tion, and fewer infiltration of lymphocytes in murine liver. Hepatic chemokine RANTES, 1P-10, and MIP-1β mRNA expression in C57BL/6 was up-regulated 2 d after intravenous administration of 3×109 PFU Ad5. Corresponding chemokine receptor CCR5, CCR1, CXCR3 mRNA expression was up-regulated 3 d after in-fection. Conclusion NKT cells play an important role in lymphocytes recruitment into the liver of mouse in-fected with AdS, which may relate to up-regulatio of the plasma IL-4, IFN-γ level and expression of FasL of NKT cells, therefore facilitating the production of chemokines, e.g. IP-10 and Mig.