INTEGRATION OF BIOLOGICAL, PROCEDURAL, APHERESIS PRINCIPLES OF PERIPHERAL-BLOOD STEM-CELL TRANSPLANTATION PROGRAMS

Collection and use of peripheral blood stem cells have rapidly replace d harvesting of pelvic bone marrow for transplant protocols. The mobil ization of progenitor populations into the peripheral blood by chemoth erapy and/or cytokine stimulation of marrow hematopoietic production h as made it possible, in general, to collect larger quantities of proge nitor populations than obtained in a single harvest of marrow. Technol ogical advances through flow cytometry and generation of monoclonal an tibodies to identify CD34 antigen expression on cells has provided a r apid means of assessing leukapheresis products for the presence of pro genitor populations and has largely replaced the laborious 14 day cult ure assays' to measure colony forming units. Unlike apheresis platelet collection, where the yields are predictable through integration of d onor biological variability, total volume of blood processed, and mach ine efficiency, CD34+ cell yields are not predictable. This has led to great diversity in stem cell collection procedures. Analyses of the s ame variables used to predict platelet yields, if applied to CD34+ cel l collection, might lead to useful algorithms for development of stand ardized guidelines for stem cell collection. (C) 1997 Published by Els evier Science Ltd.