||Helper CD4 + T cells are necessary to provide regulatory functions and direct the adaptive immune response against pathogens. CD4 + T cell malfunctions have been implicated in a variety of pathological conditions. In order for naïve CD4 + T cells to carry out their role in adaptive immune response they first must be activated by a specific antigen presented to the naïve T cell receptor by a specialized antigen presenting cell. The assembly of membrane rafts is hypothesized to key in T cell activation and proliferation. To further investigate these hypotheses, I have disrupted membrane raft formation by incorporating 7-Ketocholesterol (7-KC) into the plasma membrane of naïve T cells. By disrupting membrane rafts, I show that antigen specific T cell response is significantly diminished. These data emphasize the importance of membrane rafts in CD4 + T cell responses and furthers our understanding of the mechanisms that regulate CD4 + T cell activation.