title: Flow cytometric monitoring of red blood cell chimerism after bone marrow transplantation.
abstract: Chimerism after bone marrow transplantation (BMT) was investigated by flow cytometry analysis of red blood cells (RBCs) and of reticulocytes using a series of selected monoclonal or polyclonal antibodies directed against ABO, Rhesus, Kell, Duffy or MNSs antigens. The method allows the routine detection of less than 0.1% of positive cells in artificial mixed field populations. Blood samples from 135 patients undergoing BMT were investigated around days 15, 30, 45, 60, 90, 180, and then every 6 months after transplantation. Characteristic patterns showing expression of donor red blood cell antigens (expansion markers) and concomitant decrease of recipient specific antigens (depletion markers) within days 16-20 were observed for 125 successfully engrafted patients. Distinct patterns were obtained in 10 patients. A delay in engraftment was evidenced in four patients by the absence of chimerism during the first 6 months without any sign of relapse. Re-appearance of recipient RBCs and reticulocytes was observed in five patients; it was consistent with relapse that was later confirmed by clinical, haematological and cytogenetic studies. Finally, a stable and partial chimerism with 20% of RBCs expressing a marker from the recipient was observed in one patient without any sign of relapse. The reported investigation demonstrated that flow cytometry of RBCs and reticulocytes represents a powerful method to efficiently monitor bone marrow transplanted patients on a long-term basis.
authors.affiliation: Etablissement de Transfusion Sanguine de Loire-Atlantique/Vendée, site de Nantes, France.
authors.forename: B
authors.initials: B
authors.lastname: David
authors.forename: D
authors.initials: D
authors.lastname: Bernard
authors.forename: J M
authors.initials: JM
authors.lastname: Navenot
authors.forename: J Y
authors.initials: JY
authors.lastname: Muller
authors.forename: D
authors.initials: D
authors.lastname: Blanchard
mesh_terms: D000293:Adolescent; D000328:Adult; D000941:Antigens / Q000032:analysis; D001789:Blood Group Antigens / Q000276:immunology; D016026:Bone Marrow Transplantation; D002648:Child; D002675:Child, Preschool; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007223:Infant; D007938:Leukemia / Q000628:therapy; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012074:Remission Induction; D012156:Reticulocytes / Q000276:immunology; D013997:Time Factors; D018183:Transplantation Chimera
chemical_list: D000941:Antigens; D001789:Blood Group Antigens