CD4 and head and neck squamous cell carcinoma: To elucidate the mechanism by which factors produced by premalignant lesion cells and HNSCC cells, respectively, are modulating immune cell cytokine production, future studies will focus on the effect of lesion and tumor supernatant on isolated CD4+ and CD8+ T cells, F4/80+ macrophages, and CD11b+/CD11c+ dendritic cells.