Multicentre European study comparing selection techniques for the isolation of CD34(+) cells

Primitive haemopoietic cells are required for studies in both the clinical and research fields and a number of systems have been developed to facilita te isolation of these haemopoietic cell populations. We have analysed the r esults from several European centres using positive selection of CD34(+) ce lls from haemopoietic tissues (n = 110), Four selection techniques includin g immunoaffinity columns (Ceprate LC), immunomagnetic beads (Dynabeads, Bax ter Isolex 50) and submicroscopic magnetic beads (MACS) were used and the s elected CD34(+) cells were assessed for purity, yield and enrichment of col ony-forming cells (CFC), The mean purities for all samples ranged from 68.4 -78.4% for MACS, 33.9-69.9% for Dynabeads, 46.9-66.8% for Ceprate LC and 43 .2-65% for Baxter Isolex 50, Yields were variable,vith all techniques. On a verage CFC enrichment using the immunoaffinity columns was greater than tha t observed for the other systems. Some techniques appear to be problematic and may require further expertise to improve the results. Nevertheless, the study demonstrates that highly purified CD34(+) cells can be isolated from various haemopoietic sources, though yield and CFC enrichment varies signi ficantly depending on the technique selected. This extends our previous rep ort indicating that not all selection methods generate similar results and that there are differences in the purity, number and colony-forming ability of the cells recovered.