Abstract 3569: Transcriptional signatures in human melanoma epitope MART-127-35 specific TCR-engineered T cells

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Adoptive Cell Therapies (ACT) with T cell receptor-engineered (TCReng) T cells have shown promising results. Unfortunately, for a fuller understanding of their biology, currently available immunological assays have proven inadequate. Given that RNA-Seq using Next Generation Sequencing (NGS) offers substantial opportunities, we carried out NGS of the MART-127-35 specific TCReng human primary CD8+ and CD4+ T-cells following cognate stimulation, to obtain a comprehensive understanding of the transcriptional signatures underlying their biology. Data analyses revealed approximately 30,000 transcripts, a sizeable number of which showing up- or down-regulation covering virtually all relevant aspects of T cell biology (i.e., effector function, differentiation, proliferative activities, apoptosis, etc.) when stimulated by the cognate epitope. The transcriptional profiles of the TCReng CD8+ and CD4+ T cells were found to be remarkably similar. Additionally, 72,000 known isoforms and about 20,000 previously undescribed isoforms were detected. Interestingly, a number of long noncoding RNAs (lncRNA) - some with known functions (e.g., NEAT1 and MALAT1, both implicated in RNA editing, were up-regulated in the two cell types), and others with unknown function (e.g., GAS5, MIAT, and FTX showing modulations in expression), were also detected in both cell types. Although a comprehensive knowledge of the transcriptional signatures and a clear understanding of the spliced variants, the novel isoforms, and the lncRNAs in T cell biology will require further work, our study shows that NGS of specific epitope reactive T cells will be a very useful tool in deciphering the transcriptional controls underlying the function and the fate of epitope specific anti-tumor T cells. Citation Format: Prashant Singh, Nitya G. Chakraborty, Umar Farooq, Upendra P. Hegde, Richard Everson, David I. Dorsky, Bijay Mukherji. Transcriptional signatures in human melanoma epitope MART-127-35 specific TCR-engineered T cells. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3569. doi:10.1158/1538-7445.AM2014-3569