Expression of glucocorticoid induced tumor necrosis factor receptor ligand during acute rejection after rat liver transplantation

Abstract

Objective To investigate te changes of glucocorticoid induced tumor necrosis factor receptor ligand (GITRL) in hepatic allograft rejection. Methods Liver transplantation from Lewis rats (n = 5 ) to Brown Norway (BN) rats was performed by Kamada' s two-cuff technique as acute rejection group. Liver transplantation from BN to BN rats ( n = 5 ) was performed as tolerance group. Recipients were sacrificed at 24th h postoperation. Blood samples were collected and grafts were harvested, then Kupffer cells were isolated. GITRL and tumor necrosis factor (TNF)-α protein expression in the hver was tested by immunohistochemistry, and the GITRL expression in Kupffer cells by immunocytochemistry. Enzyme linked immunosorbent assay (ELISA) was employed to detect the changes of TNF-α protein in the serum and supernatant. The staining intensity was analyzed by Image-Pro Plus 6. 0 image analysis software. Results At 24th h postoperation, the liver GITRL expression levels in tolerance and rejection groups were 0. 113 ± 0. 007 and 0. 270 ±0. 018, respectively (P ＜0. 05). The TNF-α expression levels in the liver in tolerance and rejection groups were 0. 114 ± 0. 004 and 0. 141 ± 0. 005 respectively ( P ＜ 0.05 ). The GITRL expression levels in Kupffer cells in tolerance and rejection groups were 0. 206 ±0. 017 and 0. 337 ±0. 018 respectively (P ＜0. 05 ). As compared with tolerance group (68. 66 ±21.12) ng/L, TNF-α protein expression levels were up-regulated in the supernatant of rejection group ( 178.33 ± 29. 39 ) ng/L ( P ＜ 0. 05 ).Conclusion The expression of GITRL in the liver and Kupffer cells was increased in the early stage of rejection, and monitoring and interfering GITRL may be useful for the early diagnosis and management of an acute rejection in liver transplantation. Key words: GITRL; Liver transplantation; Acute rejection; Kupffer cells