Research on the in vitro cytotoxic effects of CAR-NK cells targeting CD20 on B-Cell Lymphoma Raji-GFP-Luc Cells

Following titer determination, the retroviruses were transduced into activated primary human NK cells to generate CD20-1.5.3 CAR-NK and CD20-Leu16 CAR-NK cells. The CAR-positive rates were determined by flow cytometry. Untransduced NK cells and the two CAR-NK cell populations were co-cultured with Raji-GFP-Luc target cells at varying effector-to-target ratios.

Thereafter, target cell lysis was quantified via a luciferase-based cytotoxicity assay for the comparative evaluation of the anti-tumor activity of the two CAR-NK cell products.Results CD20-1.5.3 CAR-NK and CD20-Leu16 CAR-NK cells were successfully generated, with CAR-positive rates of 67.5% and 87.4%, respectively. Both CAR-NK cell populations exhibited significantly enhanced cytotoxic activity against Raji-GFP-Luc cells compared to untransduced NK cells across all effector-to-target ratios tested (P < 0.05).

Notably, at lower effector-to-target ratios, the CD20-Leu16 CAR-NK cells demonstrated superior cytotoxic activity compared to the CD20-1.5.3 CAR-NK cells (P < 0.05).Conclusion Fourth-generation CD20-targeted CAR-NK cells were successfully generated and demonstrated potent in vitro cytotoxicity against Raji-GFP-Luc cells, providing experimental evidence supporting the potential application of CD20 CAR-NK cell therapy for B-cell non-Hodgkin lymphoma.