Koji Kishino

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.

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

Abstract 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 (⩾0·5×109/l) and platelet recovery (⩾20×109/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.

GUIDELINE FOR PROCESSING CELLULAR THERAPY PRODUCTS ROUTINELY USED FOR HEMATOPOIETIC STEM CELL TRANSPLANTATION IN JAPAN

既に治療法として確立している造血幹細胞移植に用いる細胞処理のガイドラインを，日本輸血・細胞治療学会と日本造血細胞移植学会との共同指針として今回初めて策定した．欧米のFACT-JACIE基準を参考にする一方で，移植施設が小規模で分散し移植に係るコメディカルの少ないわが国の状況を踏まえて，多くの施設が受容し得る内容とした．ただし，必ずしも現在の大半の施設が満たす基準ではなく「目指すべき基準（理想的な基準）」の内容も含めた．構成は，1目的，2対象，3細胞の採取，4責任者と作業者，5設備・機器，6細胞処理（プロセシング），7払い出し，8保存と解凍，9検体保存，10投与，11廃棄，12雑則からなり，教育的観点から「付」として代表的な細胞処理法に関して，解説，標準作業手順書（SOP）サンプル，記録シートサンプル，結果シートサンプルなどを設けた．今後この指針が多くの場面で運用されるように努めるとともに，現場に即した指針となるように改訂を重ねていく必要がある．また，将来的に欧米の最新の指針と同等の基準となり，また輸血・細胞処理部門認定や有害事象の監視体制を構築するのに活用されることが期待される．