Standardization and characterization of the procedure for in vitro treatment of human bone marrow with cyclophosphamide derivatives.

Thirty human bone marrow (BM) suspensions from patients with acute leukaemia patients in remission were processed with the Haemonetics 30 flow cell separator in order to separate buffy-coats and to treat them in vitro with a derivative of cyclophosphamide (ASTA Z 7557). After processing, the volumes of BM suspensions were reduced to 25%. Recoveries of leucocytes, CFUc and BFUe were respectively 62, 85 and 84%. In vitro treatment with doses of ASTA Z ranging from 50 to 140 micrograms/2 X 10(7) leucocytes (according to the CFUc sensitivity of each patient) destroyed 95 +/- 5% of initial CFUc. After freezing and thawing, recovery of CFUc from treated BM was poor (24%) in comparison to that obtained with untreated BM (79%).