A modified method for human bone marrow filtration prior to bone marrow transplantation

A technique is described for filtering harvested bone marrow using disposable materials, namely a 4 x 4 inch piece of sterile gauze that is gently packed into the barrel of a 60-ml plastic disposable syringe, which is connected directly to a blood collection bag. The filtration of marrow directly into the collection bag eliminates additional filtration steps and therefore may potentially reduce the incidence of inadvertent microbial contamination. In this study we describe this filtering technique and compare it to the method described by Thomas and Storb. Numbers of granulopoietic progenitors (CFU-GM) and erythropoietic progenitors (BFU-E), total white cell counts, percentage of cells positive for the CD3 (OKT3) lymphocyte surface membrane marker, and volume changes were studied following filtration by each method. The two techniques were shown to be comparable in terms of these parameters. Furthermore, when compared with historical controls, this method resulted in a reduced incidence of microbial contamination compared to filtration using successive stainless steel screens.