Inertial Microfluidic Purification of CAR‐T‐Cell Products

Abstract

Chimeric antigen receptor T (CAR‐T) cell therapy is rapidly becoming a frontline cancer therapy. However, the manufacturing process is time‐, labor‐ and cost‐intensive, and it suffers from significant bottlenecks. Many CAR‐T products fail to reach the viability release criteria set by regulators for commercial cell therapy products. This results in non‐recoupable costs for the manufacturer and is detrimental to patients who may not receive their scheduled treatment or receive out‐of‐specification suboptimal formulation. It is demonstrated here that inertial microfluidics can, within minutes, efficiently deplete nonviable cells from low‐viability CAR‐T cell products. The percentage of viable cells increases from 40% (SD ± 0.12) to 71% (SD ± 0.09) for untransduced T cells and from 51% (SD ± 0.12) to 71% (SD ± 0.09) for CAR‐T cells, which meets the clinical trials’ release parameters. In addition, the processing of CAR‐T cells formulated in CryStor yields a 91% reduction in the amount of the cryoprotectant dimethyl sulfoxide. Inertial microfluidic processing has no detrimental effects on the proliferation and cytotoxicity of CAR‐T cells. Interestingly, ≈50% of T‐regulatory and T‐suppressor cells are depleted, suggesting the potential for inertial microfluidic processing to tune the phenotypical composition of T‐cell products.

Separation of Activated T Cells Using Multidimensional Double Spiral (MDDS) Inertial Microfluidics for High-Efficiency CAR T Cell Manufacturing

“…The first factor is the different proliferation behaviors across the outputs. As shown in Figure 3c and represented in previous work, 30 separation of larger T cells provides a population with better viability and improved proliferation rate. In the case of the IW output, most T cells would have a good proliferation rate, whether it is activated (transducible) or unactivated (not transducible).…”

“…[16][17][18]23,28,29 Another key work by Elsemary et al presented a spiral inertial microfluidic purification device specifically designed for CAR T cell products. 30 Their study aimed to purify T cells to achieve higher viability by removing nonviable cells. The results indicated that the larger T cell population obtained from the developed device exhibited significantly improved viability for both untransduced T cells and CAR T cells.…”

“…Another key work by Elsemary et al presented a spiral inertial microfluidic purification device specifically designed for CAR T cell products . Their study aimed to purify T cells to achieve higher viability by removing nonviable cells.…”