Objective: To evaluate the effect of immunomagnetic technique in purging of peripheral blood progenitor cell (PBPC) of breast cancer patients.
Methods: A sample of APBSC from non-breast cancer patients mixed with 1% MCF-7 cell lines and 10 samples of APBSC from breast cancer patients were subjected to positive purging, negative purging, and positive/positive purging. The CD34 + cell purity, CD34 + cell recovery rate and the enrichment of colony form units were compared. The number of tumor cells before and after immunochemistry (ICC) and flow detected purging procedure cytometry (FCM). The influence of refrigeration on the effect of purging was analyzed.
Results: The TC depletion in 10 samples of PBPC of breast cancer patients after positive purging was 2.1 (1.1 approximately 2.7) log steps, the CD34 + cell purity was 55.1 (25.9 approximately 99.5)%, and the CD34 + cell recovery was 39.4 (34.0 approximately 80.0)%. After the 6 samples of ICC positive PBPC from breast cancer patients were subjected to negative selection and subsequent positive purging, the mean CD34 cell purity was 64.3 (34.0 approximately 86.4)%, the mean CD34 + cell recovery was 35.0 (24.0 approximately 52.5)%, the purging efficiency was 3.0 (1.8 approximately 3.9) log, and the enrichment of colony-forming units-granulocyte macrophage (CFU-GM) and burst-forming unit-erythrocyte (BFU-E) were 2.2 and 3.1 respectively. TCs were detectable in all 6 cases prior to the purging procedure by ICC and FCM. After the -/+ purging procedure, only one case was tumor cell positive by ICC and residual tumor cells could be detected by FCM, however the number of TCs was evidently decreased. Along with the extension of refrigeration time, the CD34 cell purity, CD34 cell recovery, and tumor cell clearance rate decreased.
Conclusion: Immunomagnetic double negative/positive selections an effective, rapid and simple purging method.