Granulocyte-macrophage colony-stimulating factor and car-t technology for solid tumors in experiment

Abstract

© 2020 Practical Medicine Publishing House. All rights reserved. Background. Cytokines are considered as important factors that enhance the efficacy of CAR-T cell therapy. Besides, they are key elements of the pathogenesis of cytokine release syndrome and neurotoxicity in applying the CAR-T technology. However, cytokine effects in the context of CAR-T therapy have not yet been properly studied. Aim. To quantitatively assess cytokine secretion using multiplex assay with co-incubation of anti-CD19 CAR-T lymphocytes with epithelial HeLa and A431 cell lines expressing CD19 on their surface. Materials & Methods. T-lymphocytes were transduced with the lentiviral vector containing anti-СD19-CAR gene. CAR expression was tested based on GFP reporter using flow cytometry. To confirm a specific CAR-T cell activation response to tumor antigen, the levels of interleukin-2, interferon-γ, and tumor necrosis factor-α were measured by means of immunoassay. Cytotoxic activity of CAR-T lymphocytes obtained was examined with their direct co-culturing with target cells. The levels of cytokines isolated prior to and after incubation of targets with CAR-T cells were compared using multiplex assay. Results. The level of some proinflammatory cytokines (interleukin-6, interleukin-1β, interferon-γ) (p < 0.01) increased. The difference in the levels of anti-inflammatory cytokines (interleukin-4, interleukin-10) was inconsiderable, and in the HeLa cell line experiment it was insignificant (p > 0.05). The concentration of granulocyte-macrophage colony-stimulating factor (GM-CSF) was many times higher after incubation with CAR-T lymphocytes (p < 0.01). Conclusion. The trial revealed multiple enhancement of GM-CSF, one of the key elements of the pathogenesis of cytokine release syndrome and CAR-T-associated neurotoxicity. The results of further studies of GM-CSF can contribute to improving the efficacy of CAR-T therapy with considerably lower toxicity.