Serological Inhibition of Graft Versus Host Disease: Recent Results in 28 Patients with Leukemia

Abstract

One major obstacle to the successful application of allogeneic bone marrow transplantation is the occurrence of immunologic complications when donor and recipient are not monozygous twins and express differences in their histocompatibility properties. Even after transplantation of HLA-identical and MLC-negative marrow grafts the occurrence of graft versus host disease (GvHD) cannot be excluded due to genetic differences not detected by present histocompatibility typing techniques. In the past, several experimental approaches have been designed to eliminate the GvH-reactive cell populations in the donor marrow by incubating the graft in vitro with specific antibody preparations whose stem cell toxicity had been absorbed by various tissues, in particular non-T-lymphocytes. Pretreatment of donor spleen marrow with absorbed anti-T cell antisera suppressed GvHD in over 90% of H-2 incompatible semiallogeneic mice preirradiated with 900 R [1]. Also monoclonal Anti-Th-1 antibodies have been effective in preventing GvH reactions in incompatible murine combinations [2]. A suppressing effect of GvHD by incubation with T-cell-specific antibodies could also be shown in a canine model transferring incompatible DLA homozygous marrow to DLA heterozygous lethally irradiated littermates [3]. Since then an anti-T-cell globulin for human cells with comparable serological characteristics has been developed [4]. The present report describes the effect of an incubation treatment with anti-T-cell globulin in 28 cases of bone marrow transplantation in acute leukemias.