The objective of this study was to compare the performance of two immunomagnetic separation technologies to deplete T cells from buffy coats of human blood. Specifically, two versions of the commercial MACS® Technology: MiniMACS and SuperMACS, and a prototype, flow-through system, the QMS, were evaluated. Peripheral blood mononuclear leukocytes (PBL) were isolated from buffy coats and an immunomagnetic separation of CD3+ cells was conducted using company and optimized labeling protocols. To mimic peripheral blood containing bone marrow purged hematopoietic stem cells, HSC, CD34 expressing-cells (KG1a) were spiked into PBL prior to T-cell depletion once optimized depletion conditions were determined. Once the labeling protocol was optimized, the MiniMACS system performed well by producing a highly enriched CD3+ fraction, and a respectable level of depletion of T cells and recovery of KG1a cells in the depleted fraction; an average log10 depletion of T cells of 2.88 ± 0.17 and an average recovery of the KG1a cells of 60.8 ± 5.94% (n = 14). The performance of the SuperMACS system was very similar with an average log10 depletion of T cells of 2.89 ± 0.22 and an average recovery of KG1a of 63.1 ± 8.55% (n = 10). In contrast, the QMS system produced an average log10 depletion of T cells of 3.98 ± 0.33 (n = 16) with a corresponding average recovery of 57.9 ± 16.6% of the spiked CD34+ cells. The aforementioned QMS performance values were obtained using sorting speeds ranging from 2.5 × 104 to 1.7 × 105 cells per second. It is suggested that the lack of a 100% recovery of the unlabeled KG1a cells is the result of a previously reported "drafting" phenomena which pulls unlabeled cells in the direction of the magnetically labeled cells thereby resulting in loss of the unlabeled cells.
- Cell separation
- HCS transplantation
- T cell depletion
ASJC Scopus subject areas
- Applied Microbiology and Biotechnology