Stable mixed donor/host hematopoietic chimerism can be accomplished in dog leukocyte antigen (DLA)-identical littermate @entity235 given sublethal (200 cGy) @entity348 ( @entity348 ) before and immunosuppression with @entity618 ( @entity2098 ) and @entity205 (CSP) after transplant (Blood 89:3048, 1997). Studies were based on the hypothesis that drugs that prevent @entity2132 ( @entity2132 ) after transplant also suppress host-versus-graft (HVG) reactions and thereby enhance engraftment. Here, we asked whether pretransplant @entity348 provided marrow space for the graft to home or caused host immunosuppression. To address the questions, recipients were given pretransplant irradiation to cervical, thoracic, and abdominal lymph nodes (except pelvis), DLA-identical littermate marrow grafts, and @entity2098 /CSP posttransplant. Six @entity235 that received 450 cGy irradiation showed initial engraftment. Two rejected their grafts after 8 and 18 weeks, 1 died with @entity2132 and engraftment, and 3 are alive as mixed chimeras after 57 to 97 weeks. Four @entity235 given 200 cGy irradiation also showed initial engraftment, but rejected their grafts after 10 to 18 weeks. Mixed chimerism was present in nonirradiated marrow and lymph node spaces and involved granulocytes, T cells, and monocytes. While other explanations are possible, results seem consistent with the hypothesis that pretransplant radiation provides host immunosuppression, and grafts can create their own marrow space. These data set the stage for the development of novel transplant regimens that substitute immunosuppressive for cytotoxic agents.

Stable mixed hematopoietic chimerism in dog leukocyte antigen-identical littermate XXXX given lymph node irradiation before and pharmacologic immunosuppression after marrow transplantation.

@entity235 :: ('9615', 'Species') :: ['dogs'] @entity205 :: ('MESH:D016572', 'Chemical') :: ['cyclosporine'] @entity2098 :: ('CHEBI:8764', 'Chemical') :: ['MMF'] @entity2132 :: ('MESH:D006086', 'Disease') :: ['GVHD', 'graft-versus-host disease'] @entity348 :: ('MESH:C535338', 'Disease') :: ['total-body irradiation', 'TBI'] @entity618 :: ('MESH:C063008', 'Chemical') :: ['mycophenolate mofetil']
@entity235 :: (9615,Species) :: ['dogs']
