Potency of human hematopoietic cells from a novel CD34+ isolation technique

Hematopoietic stem and progenitor cells are responsible for maintenance of the immune system and can be a source of cells for therapies. A critical step in studying or utilizing hematopoietic cells is subpopulation isolation. FerroBio is an emerging technology that uses a streamlined, semi-automated approach to isolate CD34+ cells, which are highly enriched for hematopoietic stem and progenitors. This technology also results in isolation of bead-free CD34+ cell samples, in contrast to traditional kits where beads persist following isolation. Here, we showed a side-by-side comparison of FerroBio isolated cells with CD34+ cells isolated by traditional column-based kits. We showed that FerroBio yields similar numbers of CD34+ cells with similar viability, yield, and gated purity and higher overall purity compared to control kits. FerroBio isolated similar numbers of progenitor cells but significantly higher stem cells. Ex vivo, cells isolated by FerroBio showed the same ability to form colonies in culture, but FerroBio colony-forming units expanded to a greater extent in liquid culture compared to control. Critically, FerroBio isolated cells had equivalent long-term engraftment capacity with significantly better intermediate-term engraftment compared to control in mouse models of transplantation. Based on microscopy images showing altered morphology co-localized with beads, we inferred that the persistence of magnetic microbeads may be associated with the observed differences. These data demonstrated that specific subpopulations of progenitors from FerroBio isolated CD34+ cells have better potency compared to cells isolated with column-based kits. Thus, FerroBio is a viable strategy for isolating CD34+ cells for research and potentially translational utility.