Expression profiles of I and sialosyl-I antigens on blood cells: the sialosyl-I antigen is expressed along the monocytic differentiation

Use of cryoprotectant-depleted allogeneic peripheral blood stem cells for transplantation

Transplantation with cryopreserved allogeneic peripheral blood stem cells (PBSCs) from related donors is widely conducted in Japan. To freeze PBSCs, a solution containing dimethyl sulfoxide (DMSO), which can have various adverse effects, is added. DMSO-depleted allogeneic PBSCs were transplanted into 21 patients. The cryoprotectant was manually removed from thawed PBSCs and the cells were mixed with a solution containing citrate dextrose as an anticoagulant and RPMI-1640 medium. DMSO-depleted PBSCs were immediately infused into patients subjected to conditioning. Infusion-related adverse effects were only observed in three patients. The median neutrophil recovery (⩾0·5×10(9)/l) and platelet recovery (⩾20×10(9)/l) were 13·0 and 14·0 days, respectively. Only one patient with mixed-lineage leukemia in non-complete remission did not show engraftment, likely due to a second transplantation and a two-antigen disparity in human leukocyte antigen system A. The results suggest the removal of DMSO from thawed PBSCs to be safe and useful for transplantation.

Evaluation of engraftment by ABO genotypic analysis of erythroid burst-forming units after bone marrow transplantation

Six patients received an allogeneic bone marrow transplant from HLA-identical ABO-mismatched donors. ABO genotype of erythroid burst-forming units (BFU-E) from peripheral blood was analyzed using polymerase chain reaction with sequence specific primers (PCR-SSP). After bone marrow transplantation (BMT), engraftment of donor cells by ABO genotypic analysis of BFU-E was compared with ABO phenotypic analysis of red blood cells (RBCs). During the early stage after BMT, ABO genotype of BFU-E in the recipients converted to that of the donors. In contrast, mixed ABO phenotype of RBCs persisted for about 3 months. In one patient, autologous hemopoietic cell recovery was detected by the ABO genotypic analysis before clinical manifestation. ABO genotypic analysis of BFU-E is relevant for enagraftment after ABO-mismatched BMT.