CD19嵌合抗原受体T细胞靶向B细胞肿瘤细胞株过程中糖皮质激素对其扩增影响的体外研究

OBJECTIVE: To evaluate the effects of glucocorticoids (dexamethasone and methylprednisolone) on the proliferation of CD19 Chimeric antigen receptor (CAR) modified T cells in vitro. METHODS: Peripheral blood mononuclear cells from healthy volunteers were collected as T cells. CD19 CAR-T cells were prepared by CD3 magnetic beads sorting and CD19 CAR lentivirus transfection. The transfection rates and the proportion of CD19 CAR-T cells in the culture system were analyzed using a flow cytometer. The mean fluorescence intensity (MFI) of CD19 CAR-T cells was measured after staining with Carboxyfluorescein diacetate succinimidyl ester cell proliferation tracer fluorescent probe, Lactate dehydrogenase (LDH) cytotoxicity assay was used to detect the effects of different concentrations of glucocorticoid on the killing activity of B-cell tumor cell lines. RESULTS: In this study, the CD19 CAR transfection rate of CD19 CAR-T cells was (51.34±5.28)％. The killing activities of different doses of methylprednisolone on Nalm6, Pfeiffer, and U2932 tumor cells were higher than that of dexamethasone at 24 h. The killing activities of 4 mg/mL methylprednisolone on Nalm6, Pfeiffer, and U2932 were higher than that of 0.75 mg/ml group, while the killing activity of 12 mg/ml methylprednisolone was lower than that of 2.25 mg/ml dexamethasone at 48 h. However, the killing activities of different doses of methylprednisolone on EHEB tumor cells were lower than those of different doses of dexamethasone at 24 and 48 h. The average MFI and proportion of CD19 CAR-T cells under different concentrations of glucocorticoid the proliferation inhibition of CD19 CAR-T cells by dexamethasone was higher than that of methylprednisolone. The proliferation inhibition of CD19 CAR-T cells of the two glucocorticoids in high concentration groups were more obvious than that in low concentration groups. When CD19 CAR-T cells were co-cultured with different tumor cells, the proportion and average MFI of CD19 CAR-T cells showed that the proliferation inhibition of dexamethasone was higher than that of methylprednisolone. The proliferation inhibition of CD19 CAR-T cells of the two glucocorticoids in high concentration groups was more obvious than that in low concentration groups. CONCLUSION: Dexamethasone inhibits the cell proliferation of CD19 CAR-T cells more than methylprednisolone during the targeting of different tumor cell lines. The inhibition effect of dexamethasone on the proliferation and amplification of CD19 CAR-T cells was greater than that of methylprednisolone during the targeting of CD19 CAR-T cells to different tumor cell lines. Moreover, the inhibition effect of the high dose group was more obvious.