ABSTRACT
The technique described by Thomas and Storb in 1970 [1] has undergone few major changes, and is still the basis of marrow harvesting today. Historically, transplant physicians have aimed to acquire 2-4×108 nucleated cells/kg recipient body weight for an unmanipulated allogeneic marrow graft, and 1-3×108 nucleated cells/kg for an unmanipulated autologous graft [2]. In general, this number of cells may be acquired with a collection of 10-20 ml of marrow/kg recipient body weight, although donors under the age of 20 years may have significantly more cells per volume harvested, while those over the age of 60 years may have significantly less [3]. When deciding how much marrow to harvest, it is imperative to know whether a graft will undergo manipulation, and what the cell loss associated with processing is likely to be, in order to harvest sufficient cells to ensure an adequate graft.
