Invitrogen™ CD86 Recombinant Rat Monoclonal Antibody (PO3)

CD86, along with CD80, is a member of the B7 family of costimulatory molecules and plays a crucial role in T cell activation and immune response regulation. CD86 is expressed at low levels on B cells, macrophages, and dendritic cells, and its expression is upregulated on B cells through various stimuli, including the BCR complex, CD40, and certain cytokine receptors. As a type I membrane protein and member of the immunoglobulin superfamily, CD86 serves as a ligand for the T cell surface proteins CD28 and CTLA-4 (CD152). The interaction between CD86 and CD28 provides a costimulatory signal essential for T cell activation during antigen presentation, while binding with CTLA-4 negatively regulates T cell activation, diminishing the immune response. This interaction is critical for T-B cell crosstalk, T cell costimulation, autoantibody production, and Th2-mediated Ig production. The kinetics of CD86 upregulation upon stimulation suggest its significant contribution during the primary phase of an immune response. CD86 and CD80 have distinct roles in T helper cell differentiation, and insufficient co-stimulation involving these molecules can induce tolerance. Alternative splicing of CD86 results in two transcript variants encoding different isoforms, with additional variants described but not fully sequenced. Dysfunction in CD86 is associated with diseases such as gallbladder squamous cell carcinoma and myocarditis.