TCR alpha/beta Monoclonal Antibody (R73), FITC, Invitrogen™

Description

• The T cell antigen receptor (TCR) consists of a ligand-specific alpha/beta heterodimer non-covalently associated with five invariant chains including the CD3 gamma/delta/eta and zeta subunits, all of which are required for efficient surface expression
• T cell activation through the TCR induces cellular differentiation and/or proliferation and the production of lymphokines and cytokines
• Both the CD3 and TCR zeta subunits are proposed to be responsible for the intracellular signal transduction events
• Majority of T cells present in the blood, lymph and secondary lymphoid organs express TCR alpha/beta heterodimers, whereas the T cells expressing TCR gamma/delta heterodimers are localized mainly in epithelial tissues and at the sites of infection
• The subunits of TCR heterodimers are covalently bonded and associate with the CD3 subunits in the endoplasmic reticulum to form functional TCR-CD3 complex
• Lack of expression of any of the chains is sufficient to stop cell surface expression
• The ability of T cell receptors (TCR) to discriminate foreign from self-peptides presented by major histocompatibility complex (MHC) class II molecules is essential for an effective adaptive immune response
• TCR recognition of self-peptides has been linked to autoimmune disease
• Mutant self-peptides have been associated with tumors
• Engagement of TCRs by a family of bacterial toxins know as superantigens has been responsible for toxic shock syndrome
• Autoantibodies to V beta segments of T cell receptors have been isolated from patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE)
• The autoantibodies block TH1-mediated inflammatory auto-destructive reactions and are believed to be a method by which the immune system compensates for disease (ref5)
• T Cell and TCR Diversity Most human T cells express the TCR alpha-beta and either CD4 or CD8 molecule (single positive, SP)
• A small number of T cells lack both CD4 and CD8 (double negative, DN)
• Increased percentages of alpha-beta DN T cells have been identified in some autoimmune and immunodeficiency disorders
• Gamma-delta T cells are primarily found within the epithelium
• They show less TCR diversity and recognize antigens differently than alpha-beta T cells
• Subsets of gamma-delta T cells have shown antitumor and immunoregulatory activity.