Expression Of TNFR1 In Fulminant Hepatic Failure Of Mice Induced By LPS And GalN

Fulminant hepatic failure (FHF) is a kind of severe disease in clinic. The patients' liver function may deteriorate rapidly, and sometimes they have to receive a liver transplantation in the end. The mechanism of FHF has not been understood clearly yet. It is supposed that liver necrosis is caused by cytokines network, which may be activated by a variety of inducing factors. Tumor necrosis factor (TNF) is one of most important cytokines, which can be classified into TNF - α, secreted by mononuclear and macrophage, and TNF -β, secreted by lymphocyte. Depending on the transmembrane receptor, TNFR1, to elecit its function, TNF - α plays a key role in the course of FHF. To understand the pathogenesis of FHF, it is critical to study the expression and function of TNFR1 in liver cell membrane. In this study, we detect the expression of TNFR1 in liv-er membrane of mice with FHF induced by LPS and GaIN at deferent time points. We also detect the blocking effect of anti - TNF - α antibody and anti -TNFR1 antibody in the course of FHF.METHOD1. Constituting animal model. 208 male BALE/ c mice were divided randomly into 6 groups. The mice in first group acted as control, which were injected NaCl to the peritoneum celiac. The second group were injected LPS l0μg/ kg, the third group received GaIN 800mg/kg, the fourth received both LPS 10μg/kg and GaIN 800mg/kg, the fifth and sixth groups received not only LPS 10μg/kg and GaIN 800mg/kg but also anti - TNF - α 100mg or anti - TNFR1 l00mg. The mice in the second, third and fourth groups were killed at 2nd, 6th ,9th, 12th and 24th hour after injection. Mice in the first, fifth, and sixth groupsixth group were killed at 9th hour. Blood and liver specimens were stored for test.2. Examining ALT at different time points in different groups.3. Staining liver specimens by HE method to confirm whether and how much they were injured. Immunohistochemistry method was applied to detect TNFR1 expression in liver cells at different time points of different groups.4. Using SPSS software to do the statistics analysis. One - way AN OVA was used to determine whether the difference of ALT level had any statistics significance among groups.RESULTS1. Mice in the fourth group began to die after six hours, mortality was 16. 2% , and it reached peak at the ninth hour of 60%. The mice living after 12 hours would survive. Total mortality was 66. 6%.. No mice in other groups died.2. ALT in the fourth group at 2nd hour was similar to the other groups. ALT at 6th, 9th, 12th,and 24th hour rised to 2054.18 654.26U/L, 7972.33 1332.18U/L, 10165.25 981.54U/L, and 6877.14 1763. 63U/L respec-tively. It was significantly higher than that of other groups at the same time ( p < 0. 05 ). The ALT of 9th hour in group 5 and 6 was 257. 06 83. 19U/L and 1116. 8 231. 30U/L respectively, which was significantly lower than it in group 4(p<0.05).3. By HE staining, liver cells in group 4 showed necrosis and infiltration of inflammatory cells, which became obviously with time passed. And it peaked at 9 hour and a little better at 12th hour. Similar courses were observed in group 2 and 3 , but it is less seriously. Pathological changes were less seriously in group 5 and 6. By immunohistochemistry assay, we found that TNFR1 began to express after 2 hours in the fourth group, and became more and more after time passed and peaked at 9th hour. There were much less TNFR1 expression in group 2 and 3.CONCLUSIONInjection GalN or LPS separately does not induce FHF in mice. But injection both of them could lead to FHF, which can be blocked by anti - TNF antibody and anti - TNFR1 antibody. The expression of TNFR1 in liver cells is correlative to the degree of liver damnification.