Survival of transfused donor white blood cells in HIV-infected recipients

The appearance and expansion of donor white blood cells in a recipient afte r transfusion has many potential biologic ramifications. Although patients with HIV infection are ostensibly at high risk for microchimerism, transfus ion-associated graft-versus-host disease (TA-GVHD) is rare. The purpose of this study was to search for sustained microchimerism in such patients. Blo od samples were collected from 93 HIV-infected women (a subset from the Vir al Activation Transfusion Study, an NHLBI multicenter randomized trial comp aring leukoreduced versus unmodified red blood cell [RBC] transfusions) bef ore and after transfusions from male donors. Donor lymphocytes were detecte d in posttransfusion specimens using a quantitative Y-chromosome-specific p olymerase chain reaction (PCR) assay, and donor-specific human leukocyte an tigen (HLA) alleles were identified with allele-specific PCR primers and pr obes. Five of 47 subjects randomized to receive nonleukoreduced RBCs had de tectable male lymphocytes 1 to 2 weeks after transfusion, but no subject ha d detectable male cells more than 4 weeks after a transfusion. In 4 subject s studied, donor-specific HLA haplotypes were detected in posttransfusion s pecimens, consistent with one or mom donors' cells. None of 46 subjects ran domized to receive leukoreduced RBCs had detectable male lymphocytes in the month after transfusion. Development of sustained microchimerism after tra nsfusion in HIV-infected patients is rare; HIV-infected patients do not app ear to be at risk for TA-GVHD. (C) 2001 by The American Society of Hematolo gy.