Prevention of Graft-Versus-Host Disease by Intrathymic Injection of Recipient-Type Splenocytes into Donor

The study demonstrated that graft-versus-host disease (GVHD) could be prevented by tolerizing graft donors to host antigens through intrathymic injection of recipient-type splenocytes into donors. In a model using Lewis rats as donors and (Lewis x Brown Norway)F1 rats as recipients, five treatment groups were tested. The group receiving both antilymphocyte antiserum (ALS) intraperitoneally and intrathymic allograft (group 4) showed no signs of GVHD in any of the 14 hosts up to 300 days post-injection. This indicated that the thymic route was superior for tolerance induction compared to the intravenous route, and a single ALS injection was necessary to eliminate the antihost response from the donor.