Investigating the effect of treatment with thalidomide on the expression of inflammatory and anti-inflammatory genes in monocyte-derived dendritic cells and their co-culture on the response of autologous T cells (cancer vaccine production)

Abstract

Dendritic cells (DCs) are highly specialized antigen-presenting cells that integrate a variety of signals and regulate the immune responses. DCs and antigen-specific T cells interact to generate antigen-specific T cell responses, including their activation or development of tolerance. Thalidomide is a drug that was initially used as a sedative, however was quickly abandoned due to its teratogenic effects. This drug is known as a strong suppressor of the immune system due to its anti-inflammatory and anti-angiogenic properties. But it has been demonstrated that thalidomide and chemically related drugs like lenalidomide and pomalidomide, which have a similar structure, improve the function of DCs by interfering with several signaling pathways in cells. Our aim in this study was to investigate the effects of thalidomide on the differentiation, maturation and expression of inflammatory markers in thalidomide treated DCs and the impact of this treatment on the response of T cells in T/DC co-cultures. Materials and methods After isolation of peripheral blood mononuclear cells (PBMCs) using the Ficoll technique, monocytes were isolated from PBMCs by MACS method. After cultivating monocytes in 6-well plates and adding cytokines including granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4), the plate was placed in the incubator and checked daily for contamination. On day 3, half of the medium on the wells was slowly removed and replaced with fresh medium containing cytokines. After examining the differentiation of mo-DCs by flow cytometry, mo-DCs were treated with thalidomide. To investigate the effect of thalidomide treatment on the phenotypic characteristics of mo-DCs, flow cytometry technique was used. The real-time PCR method was used to investigate the gene expression of various inflammatory and anti-inflammatory factors in treated and untreated mo-DC groups. Finally, to investigate the effect of thalidomide-treated-mDCs on the T cells response, the expression levels of T-bet, IFN-ɤ, FOXP3, and TGF-β genes in co-cultured T cells with mDCs was investigated by real-time PCR method. Results Thalidomide treatment significantly increased the expression of the maturation and antigen-presentation-related markers including CD11c, CD86, and HLA-DR in mDCs. Also, this treatment increased IL-12 gene expression in mDCs. Co-culture of autologous T cells and Thalidomide-mDCs led to enhanced expression of IFN-ɤ and T-bet in T cells compared to mDC/T cells co-cultures. Conclusion Treatment of DCs with thalidomide significantly improves their maturation and stimulatory capacity. In addition, treated DCs can increase the gene expression of anti-tumoral cytokines in co-cultured T cells. Our findings showed that thalidomide can be used as an adjuvant for application in cancer immunotherapy with DC vaccine. Keywords DC, T cells, Thalidomide, Cancer