Genetic Engineering of the Murine Melanoma D5.1G4 to Express a Model Antigen for Evaluation of Anti‐tumor CD8+ T Cell Responses

Skin cancers are among the most common form of all cancers and specifically melanoma accounts for 5% of skin cancer cases, affecting 76,100 Americans and resulting in 9,710 deaths in 2013. Due to the prevalence of melanoma in the population and it's potential to metastasize throughout the body, extensive research has been conducted in order to develop novel therapies, including immunotherapeutic approaches, for treating this disease. Prior research in a murine model has explored CD8+ T cell responses to an ovalbumin‐expressing transfectant of B16‐F1, a highly tumorigenic melanoma cell line. While CD8+ T cell responses elicited against this tumor exhibit limited effector function, it is unknown how the responsiveness of these cells compares with those elicited against melanomas that are immunologically controlled. Importantly, the chemically mutated variant of B16 known as D5.1G4 is significantly less tumorigenic than its wild type counterpart, and we have therefore recently transfected this D5.1G4 melanoma with a plasmid encoding ovalbumin so that we may compare the quality of CD8+ T cell responses to the OVA 257 epitope derived from this antigen and expressed on both B16‐cOVA and D5.1G4‐cOVA melanomas. In this study, we provide a characterization of the expression of OVA 257 in the context of the H‐2K b MHC class I molecule on both of these tumors. This system will serve as an excellent model for future studies of CD8+ T cell responses against melanomas of differing tumorigenicities.