Abstract
Autologous cell therapy has proven to be an effective treatment for
hematological malignancies. Cell therapies for solid tumors are on the
horizon, however the high cost and complexity of manufacturing these
therapies remain a challenge. Routinely used open steps to transfer
cells and reagents through unit operations further burden the workflow
reducing efficiency and increasing the chance for human error. Here we
describe a fully closed, autologous bioprocess generating MAGE-B2 TCR-T
cells. This bioprocess yielded 5 – 12e9 MAGE-B2-specific TCR-expressing
T cells, transduced at low MOIs, within 7 to 10 days, and cells
exhibited an enriched memory T cell phenotype and enhanced metabolic
fitness. It was demonstrated that activating, transducing, and expanding
leuko-apheresed cells in a single bioreactor without a T cell enrichment
step promoted lentivirus transduction efficiency while resulting in
comparable level of T cell purity (~97%) as that of
leukopak cells that went through CD8+ and CD4+ positive selection. The
critical process parameters of the bioreactor, including culturing at a
high cell density (7e6 cells/mL), adjusting rocking agitations during
phases of scale up, lowering glycolysis through addition of
2-Deoxy-D-glucose (2-DG), and modulating IL-2 levels, were shown to
positively regulate TCR expression and cell doubling time, and promote
resistance to effector-associated apoptosis of TCR-T cells. The
bioprocess described herein supports scale-out feasibility by enabling
processing of multiple patients’ batches in parallel within a Grade C
cleanroom.