Bone marrow separation, purification and cryopreservation: application for autologous bone marrow transplant (ABMT)

Autologous bone marrow transplantation is used in the treatment of patients suffering from malignant diseases. The intention of this study was to develop a technique for cryopreservation of bone marrow stem cells. A technique of purification described elsewhere (2), gave recoveries of 80% of nucleated blood cells and 87% of mononucleated blood cells after apheresis and centrifugation of buffy-coat, but when applied to bone marrow only 59% of NBC and 32% of CFUc have been harvested. We therefore modified the apheresis technique and replaced the centrifugation step by sedimentation with hydroxy-ethyl-starch. This change resulted in a small but significant increase in the yield of bone marrow cells and improved the asepsis of the procedure. From a second group of bone marrow handled with this modified protocol, final yields of 46% of NBC and 62% of MNC were obtained. After cryopreservation 87% of NBC were recovered as assessed by counting.