标准化 CAR-T 细胞监测的挑战：两种流式细胞术方法的比较及与 qPCR 技术的相关性

Chimeric antigen receptor (CAR) T-cell therapy is a breakthrough in hematologic malignancies, such as acute B lymphoblastic leukemia (B-ALL). Monitoring this treatment is recommended, although standardized protocols have not been developed yet. This work compares two flow cytometry monitoring strategies and correlates this technique with qPCR method.

CAR-T cells were detected by two different flow-cytometry protocols (A and B) in nine blood samples from one healthy donor and five B-ALL patients treated with Tisagenlecleucel (Kymriah , USA). HIV-1 viral load allowed CAR detection by qPCR, using samples from seven healthy donors and nine B-ALL patients. CAR detection by protocol A and B did not yield statistically significant differences (1. 9% vs. 11. 8% CD3 + CAR+, p = 0. 07).

However, protocol B showed a better discrimination of the CD3 + CAR+ population. A strong correlation was observed between protocol B and qPCR (r = 0. 7, p < 0. 0001). CD3 + CAR+ cells were detected by flow cytometry only when HIV-1 viral load was above 10 4 copies/mL.

In conclusion, protocol B was the most specific flow-cytometry procedure for the identification of CAR-T cells and showed a high correlation with qPCR.

Further efforts are needed to achieve a standardized monitoring approach.