 While targeting BRAF can lead to survival benefits in patients with melanoma expressing BRAF mutation it is becoming increasingly apparent that the immune system is important in modulating the growth of melanoma. As such there are immune therapies FDA approved for the treatment of stage IV melanoma including ipilimumab which confers an overall survival benefit by activating the immune system through inhibition of the CTLA-4 protein expressed on certain T-cells. Little is known about how the exposure of different classes of immune cells to vemurafenib modulates the activity of the immune system. We do know that many melanomas express differentiation antigens which could potentially be recognized by the immune system. This recognition could potentially be utilized in the development of novel immunotherapeutic treatment approaches. The pharmacologic inhibition of the MAPK pathway does lead to increased expression of various melanoma differentiation antigens along with improved recognition by antigen-specific T-lymphocytes. Evaluation of a limited number of tumor biopsy specimens suggest that the infiltration of melanomas by CD4 and CD8 T-lymphocytes markedly increases following treatment with a BRAF inhibitor. Furthermore the viability and function determined using assays for cytokine release assays and cytotoxic activity of T-lymphocytes was not negatively affected by exposure to vemurafenib at concentrations known to cause anti-tumor effects. 