The prevention of graft-versus-host disease by the serum of liver retransplanted rats

Abstract

The effect of serum from orthotopic liver retransplanted plants (re-OLT serum) on graft-versus-host disease (GVHD) was studied in rats. In the re-transplantation model of rat liver, orthotopic liver transplantation (OLT) was carried out in the DA (RT1 a) into PVG (RT1 c) combination; two days later the DA liver was removed and a new PVG liver implanted into the same recipient (re-OLT). In the in vivo GVHD model, male PVG rats were sublethally irradiated and injected intravenously with 3 × 10 8 DA or BN (RT1 n) spleen cells through the penial vein. Within 1 h of the inoculation, rats of the experimenta;l group were injected with 1 ml of re-OLT serum taken at postoperative day (POD) 7. Rats in the control group received 1 ml of normal PVG serum or syngeneic re-OLT inoculation of DA or BN spleen lymphocytes. However, when the animals were treated with re-OLT serum, 100% ( 6 6 ) of the rats survived more than 60 days, following inoculation with DA lymphocytes but now with BN lymphocytes. The POD 7 re-OLT serum showed a strong inhibition against DA anti-PVG mixed lymphocyte reaction (MLR), although re-OLT serum did not contain soluble DA class I antigens, anti-DA class I or II antibody. The potential GVHD inhibitory factors in re-OLT serum may be two unique immunosuppressive proteins, which have been detected by SDS PAGE and reported previously. We conclude that re-OLT serum has immunisuppressive factors, which, at least in part, prevented the induction of GVHD in rats.