MD Anderson Study Finds Immature Cord Blood NK Cells Undermine CAR NK Therapy

Researchers at the University of Texas MD Anderson Cancer Center discovered that a small population of immature natural killer (NK) cells present in donor umbilical cord blood can impair the activity of chimeric antigen receptor (CAR) NK cell therapies. These immature NK cells engage in trogocytosis, acquiring tumor antigens and mistakenly directing engineered CAR NK cells to attack each other instead of cancer cells. Cord blood units enriched for mature NK cells were linked to stronger therapeutic responses and better patient outcomes, while higher levels of immature NK cells correlated with reduced efficacy.

The team demonstrated that removing immature NK cells during manufacturing restores CAR NK cell potency and improves tumor control in pre‑clinical models. This finding offers a practical manufacturing strategy to enhance the consistency and effectiveness of off‑the‑shelf CAR NK cell products.