Description: The 14D3 monoclonal antibody reacts with human CD152, also known as cytotoxic T lymphocyte antigen-4 (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 (B7-1) and CD86 (B7-2), 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. Applications Reported: This 14D3 antibody has been reported for use in intracellular staining followed by flow cytometric analysis. Applications Tested: This 14D3 antibody has been pre-titrated and tested by intracellular staining and flow cytometric analysis of stimulated human peripheral blood cells using the Intracellular Fixation and Permeabilization Buffer Set (cat. 88-8824) and protocol. Please refer to Best Protocols: Protocol A: Two step protocol for (cytoplasmic) intracellular proteins located under the Resources Tab online. This can be used at 5 μL (0.06 μg) per test.A test is defined as the amount (μg) of antibody that will stain a cell sample in a final volume of 100 μL. Cell number should be determined empirically but 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. APC-eFluor™ 780 emits at 780 nm and is excited with the Red laser (633 nm). Please make sure that your instrument is capable of detecting this fluorochrome. Light sensitivity: This tandem dye is sensitive to photo-induced oxidation. Please protect this vial and stained samples from light. Fixation: Samples can be stored in IC Fixation Buffer (Product No. 00-8222) (100 μL of cell sample + 100 μL of IC Fixation Buffer) or 1-step Fix/Lyse Solution (Product No. 00-5333) for up to 3 days in the dark at 4°C with minimal impact on brightness and FRET efficiency/compensation. Some generalizations regarding fluorophore performance after fixation can be made, but clone specific performance should be determined empirically. Excitation: 633-647 nm; Emission: 780 nm; Laser: Red Laser. Filtration: 0.2 μm post-manufacturing filtered. 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.
|Human, Rhesus Monkey|
|4° C, store in dark, DO NOT FREEZE!|
|PBS with 0.2% BSA and 0.09% sodium azide; pH 7.2|