Invitrogen™ CD152 (CTLA-4) Monoclonal Antibody (14D3), Brilliant Ultra Violet™ 805, eBioscience™, Invitrogen™

Description

The 14D3 monoclonal antibody reacts with human CD152, also known as CTLA-4. CTLA-4, a protein with structural similarities to CD28, is expressed on activated T cells (activated B cells may also express CTLA-4) and binds the B7 family members, CD80 and CD86, with higher affinity than CD28 does. CTLA-4 and CD28 appear to deliver opposing signals to T cells: while CD28 is a potent costimulator, CTLA-4 restricts the progression of T cells to an activated state by inhibiting IL-2 secretion and cellular proliferation. The cytoplasmic portion of CTLA-4 contains ER retention motifs, resulting in intracellular localization of a large proportion of newly synthesized CTLA-4 in response to TCR signaling. The 14D3 antibody also recognizes rhesus monkey and has inhibitor activity. This 14D3 antibody has been reported for use in flow cytometric analysis. This 14D3 antibody has been pre-diluted and tested by intracellular staining followed by flow cytometric analysis of stimulated normal human peripheral blood cells using the Intracellular Fixation & Permeabilization Buffer Set (Product # 88-8824-00). This may be used at 5 μL (0.25 μg) per test. Cell number can range from 10^5 to 10^8 cells/test. Furthermore, due to the intracellular localization of a large portion of CTLA-4, for complete detection it may be necessary to assess intracellular expression, in addition to surface expression of CTLA-4. Brilliant Ultraviolet 805 is a tandem dye that emits at 797 nm.

CTLA4 (Cytotoxic T-Lymphocyte Antigen 4) is a CD28-family receptor expressed on mainly CD4+ T cells. It binds the same ligands as CD28 (CD80 and CD86 on B cells and dendritic cells), but with higher affinity than CD28. However, in contrast to CD28 which enhances cell function when bound at the same time as the T cell receptor, CTLA4 inhbits the T cell and prevents it from functioning. Intracellular CTLA4 is also found in regulatory T cells and may be important to their function.