Effective chimeric antigen receptor (CAR)-T cell therapy is dependent on optimal cell culture methods conducive to the activation and expansion of T cells ex vivo, as well as infection with CAR. Media formulations used in CAR-T cell manufacturing have not been optimized for gene delivery, cell expansion, and overall potency. Bioactive components and derivatives that support the generation of functionally-competent T cell progeny with long-lasting persistence are largely undefined. Current media formulations rely on fetal bovine serum (FBS) or human serum (HS), which suffer from a lack of consistency or supply issues. We recognize that components of blood cellular fractions that are absent in serum may have therapeutic value. Here we investigate whether a concentrated growth factor extract, purified from human transfusion grade whole blood fractions, and marketed as PhysiologixTM xeno-free (XF) hGFC (Phx), supports CAR-T cell expansion and function. We show that Phx supports T cell proliferation in clinical and research-grade media. We also show that Phx treatment enhances lentiviral-mediated gene expression across a wide range of multiplicity of infections (MOIs). We compared the ability of anti-GD-2 CAR-T cells expanded ex vivo in medium conditioned with either Phx or HS to clear tumor burden in a human xenograft model of neuroblastoma.
Ghassemi S, Martinez-Becerra FJ, Master AM, Richman SA, Heo D, Leferovich J, Tu Y, García-Cañaveras JC, Ayari A, Lu Y, Wang A, Rabinowitz JD, Milone MC, June CH, O’Connor RS. Enhancing Chimeric Antigen Receptor T Cell Anti-tumor Function through Advanced Media Design. Mol Ther Methods Clin Dev. 2020 Jul 9;18:595-606. doi: 10.1016/j.omtm.2020.07.008. PMID: 32775494; PMCID: PMC7397397.