Characterization of antigen-specific CD8+ T cells response after in vivo treatment with 5-aza-2'-deoxycytidine.

Abstract

Cancer is a result of a series of events that alter the normal properties of cells. Those cells begin to proliferate uncontrollably, invading tissue and impairing the function of a given system of the body. Cancer cells also have the ability to evade the immune system by a mechanism denominated immunoediting. Therefore, the currently search is for treatments in which the immune system could re-start to recognize cancer cells. Thus, besides the immunotherapy in which was considered a breakthrough in the past years, the epigenetics changes observed in cancer cells seems to be another key for treatment. The current belief is that tumor suppressor genes are methylated in cancer cells, and that the DNA demethylating agents would act by re-activating those genes. Nevertheless, recently, it was shown that these drugs induce the expression of endogenous retroviral genes that would fold into dsRNA leading the cell to be recognized as a virus-infected cell. This process makes the cancer cells more immunogenic by triggering a more effective immune response. However, very little is known about the action of DNA demethylating agents in vivo on CD8+ T cells. Thus, this project aims to fully characterize the CD8 T cell after treatment with 5-aza-22-deoxycytidine in vivo. We will immunize mice with recombinant adenovirus carrying the OVA protein and treat them or not with 5-aza-22-deoxycytidine. After, we will isolate the antigen-specific CD8+ T cells and perform transcriptome (RNAseq and qPCR) and methylome analyses (methylation assay) together with other evaluations such as cytokine production (ICS and ELISA) and proliferation activity.