Culturing neutrophils from human CD34⁺ HSPCs: Why medium matters

The cell culturing field is constantly improving cell differentiation protocols to better study and recapitulate human immune cells. The most appropriate culturing medium, which growth factors to use, and supplementation of cytokines need to be optimized. In this study, two cell culturing media for differentiating CD34⁺ hematopoietic stem and progenitor cells (HSPCs) into neutrophils were compared. Iscove's Modified Dulbecco's Medium (IMDM) resulted in hybrid neutrophil-like cells, expressing higher levels of CD14 and HLA-DR next to the typical neutrophil surface proteins. Serum-free Stemline-II (SL-II) medium resulted in cells closely resembling functional human blood neutrophils. Since CD34⁺ HSPCs cultured in SL-II medium outperform the more standard IMDM in neutrophil differentiation, a viable replacement for the discontinued SL-II medium is required. Lonza TheraPEAK X-Vivo 15 Serum-Free Hematopoietic Cell Medium, Cell Genix GMP Stem Cell Growth Medium, and StemMACS PSC-Brew XF were tested as possible replacements, from which StemMACS PSC-Brew XF seems most promising.