Activation Of The Immune Response: Antigen Presenting Cell Activates T-lymphocytes (smaller C Royalty-Free Stock Image

Dendritic cells present antigens green to lymphocytes through their membran bound MHC-molecules violet. CD4 molecules light blue bind to other portions of the MHC, strengthening the interaction. After binding to the MHC-antigen complex, The T-cell receptor blue sends a signal cascade through an attached G-protein into the T-lymphocyte cell, that activates an immune response.