Failure of autologous marrow reconstitution after cytolytic treatment of marrow with anti-Ia monoclonal antibody

Abstract

Hematopoietic stem cell toxicity of the murine monoclonal antibody 7.2, recognizing Ia-like antigens on canine cells, was tested in an autologous bone marrow transplantation model. Dogs were given 9.2 Gy of total body irradiation followed by the infusion of autologous marrow treated by one of two methods to remove Ia+ cells. In six dogs, the marrow cells were pelleted, treated with antibody 7.2 (1:1,000) and rabbit complement (1:4), resuspended in culture medium, and infused. All six dogs had prompt and sustained engraftment surviving >26 days. Indirect immunofluorescence showed, however, that the depletion of Ia+ cells was incomplete. Four dogs received marrow cells first separated by densi..