084 Neoantigen-specific T cell responses constrain cutaneous squamous cell carcinoma

The role of neoantigens in generating T cell responses that control cutaneous squamous carcinoma (cSCC) is unknown. To investigate this, solar UV-induced invasive cSCC tumors were used to create clonal lines on the BALB/c background. These constitutively express MHC class I, and thus, can be targeted for destruction by CD8 cells. Intradermal injection these cells reliably forms wild-type mice. grow faster athymic mice, lacking mature cells, compared supporting constrain growth. Both CD4 expressing granzyme B+ IFN-γ+, infiltrate tumors. Mice depleted or alone have increased tumor growth, mice both fastest demonstrating a controlling Vaccination with irradiated completely protects from challenge, this response dependent another line does not protect vaccination-induced protection due shared antigen. Whole exome RNA sequencing was performed two lines. identify anticipated elicit responses, missense mutations prioritized based predicted binding affinity, presentation MHC, expression. do share any neoantigens, vaccination neoantigen specific. results support neoantigen-specific growth model. This model will enable identification features promote rejection.