用于治疗慢性淋巴细胞白血病患者的抗 CD19 CAR-T 细胞制备优化

T cells expressing anti-CD19 chimeric antigen receptors (CARs) have activity against chronic lymphocytic leukemia (CLL), but complete response rates range from 18% to 29%, so improvement is needed. Peripheral blood mononuclear cells (PBMCs) of CLL patients often contain high levels of CLL cells that can interfere with CAR T cell production, and T cells from CLL patients are prone to exhaustion and other functional defects.

We previously developed an anti-CD19 CAR designated Hu19-CD828Z. Hu19-CD828Z has a binding domain derived from a fully human antibody and a CD28 costimulatory domain.

We aimed to develop an optimized process for producing Hu19-CD828Z-expressing T cells (Hu19-CAR T) from PBMC of CLL patients.

We determined that supplementing Hu19-CAR-T cultures with interleukin (IL)-7 + IL-15 had advantages over using IL-2, including greater accumulation of Hu19-CAR T cells during in vitro proliferation assays.

We determined that positive selection with anti-CD4 and anti-CD8 magnetic beads was the optimal method of T cell purification because this method resulted in high T cell purity.

We determined that anti-CD3/CD28 paramagnetic beads were the optimal T cell activation reagent.

Finally, we developed a current good manufacturing practices-compliant clinical-scale protocol for producing Hu19-CAR T from PBMC of CLL patients. These Hu19-CAR T exhibited a full range of in vitro functions and eliminated leukemia from mice.