Donor-HLA-incompatible Marrow Transplantation with an Anti-donor Cytotoxic Antibody in the Serum of the Patient

A 42-year-old female with acute mixed lineage leukemia received a marrow transplantation from an HLA non-identical sibling. The serum of the patient showed a positive crossmatch for anti-donor lymphocytotoxic antibody and exhibited a complement-mediated cytotoxicity to donor hematopoietic progenitor cells. In an attempt to reduce the risk of graft rejection, a large volume plasma exchange was performed, which was followed by an infusion of irradiated donor lymphocytes to eliminate remaining antibodies from her serum. The level of anti-donor antibody fell below the sensitivity of the anti-human immunoglobulin lymphocytotoxicity test after the infusion of donor lymphocytes. The cytotoxic activity against donor progenitor cells also disappeared from the serum. Cyclosporin had been administered for 2 weeks before marrow infusion, and methylprednisolone and prednisolone for 1 week before the initiation of conditioning chemoradiotherapy. Conditioning comprised cytosine arabinoside 5.6 g/m2, cyclophosphamide 4500 mg/m2 and fractionated total body irradiation with 15 Gy followed by an infusion of 4.0 x 10(8) cells/kg of unmodified marrow cells. Engraftment of donor cells was documented by HLA typing of peripheral lymphocytes. A sustained engraftment may be obtained in a donor-incompatible HLA non-identical marrow transplantation with anti-donor antibody by elimination of the antibody and achieving an intensive immunosuppression in the recipient before marrow infusion.