[Effects of partial hepatectomy on the alloimmune responses in mice]

The alloimmune responses in mice were studied. As a model of hepatic damage, groups of 6-8 week old male BALB/c mice were subjected to 70% partial hepatectomy (PH). When PH was performed 5-8 days prior to C3H/HeN skin grafting, the mean skin graft survival time of ALS-treated mice was prolonged. In addition, inhibited delayed type hypersensitivity against allogeneic spleen cells in PH mice was measured by a footpad increment assay. Immunosuppressive acidic protein (IAP) levels increased in the sera from 5 to 8 days following PH, then decreased within 14 days. Chemiluminescence analysis specific to each subclass of spleen macrophage Fc-receptors (FcRs) revealed pronounced expression of not only FcR-I but FcR-II in mice from 5 to 8 days following PH. Alloreactive CTL induction in the spleen cells of mice 8 days following PH was suppressed. Its immunosuppressive property was found in the macrophage fraction which was activated in the spleen of PH mice. In conclusion, suppressed alloimmune responses were observed in PH mice. This suggests that in the process of liver regeneration following PH, the activated suppressor macrophages in the spleen may be playing an important role in this phenomenon.