The effects of perioperative administration of donor lymphocytes via portal vein in rat skin transplant model]

The effects of perioperative portal venous (P.V.) administration of donor lymphocytes on skin allograft survival were investigated in rat skin transplant model. Heterotopic skin transplantations were performed form Brown-Norway (BN, RT-1n) to Lewis (LEW, RT-1(1] male rats. P.V. administration of donor BN lymphocytes (1 x 10(8] resulted in significant prolongation of BN skin graft survival (MST = 13.4 +/- 3.9 days, p less than 0.05) compared with I.V. administration of same number of donor lymphocytes (8.6 +/- 1.2 days) or with PV administration of third party DA (RT-1a) rat's lymphocytes (7.4 +/- 0.8 days) or with untreated controls (9.0 +/- 1.4 days). These results suggested that this effect was antigen specific. P.V. administration of donor lymphocytes prevented recipient which received BN skin graft form developing delayed-type hypersensitivity responses to donor antigen. Serum from LEW recipients which induced unresponsiveness by PV administration with donor BN lymphocytes had significant antigen specific suppressor effect (77.0 +/- 5%) on the MLR proliferative reaction of LEW responder cells toward donor BN cells, but not third party DA stimulation. Moreover, this immunological unresponsiveness was transferable by the serum in kidney transplant model. These results indicate that PV administration of donor lymphocytes induces recipient's unresponsiveness to donor alloantigen in rat skin transplant model, and this effect is transferable by the suppressor factor in the serum.