CD4/CD25 Antibody Cocktail, FITC, PE, eBioscience™

Product Specific Information

Description: This product consists of two fluorochrome-conjugated monoclonal antibodies to identify CD4+CD25+ human peripheral blood cells. The RPA-T4 monoclonal antibody (mouse IgG1, kappa) reacts with human CD4, a 59 kDa cell surface receptor that is expressed by a majority of thymocytes, a subpopulation of mature T cells (T helper cells) and at low levels on monocytes. The BC96 monoclonal antibody (mouse IgG1, kappa) reacts with human CD25, the 55 kDa interleukin-2 receptor alpha chain (IL-2Ralpha). This cocktail of RPA-T4 and BC96 can be used for the flow cytometric detection of human regulatory T cells, which also express Foxp3.

Applications Reported: This product has been reported for use in flow cytometric analysis.

Applications Tested: This cocktail has been pre-titrated and tested by flow cytometric analysis of normal human peripheral blood cells. This can be used at 20 µL per test (containing 1 µg of Anti-Human CD4 (RPA-T4) FITC and 0.125 µg of Anti-Human CD25 (BC96) PE). 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.

Target Information

The CD4 antigen is involved in the recognition of the type II MHC antigen. It is also a receptor for HIV. It is present on most T helper cells and normal thymocytes. The cytoplasmic portion of CD4 is associated with p56lck tyrosine kinase. CD4 expression is commonly found in human lymph nodes and tonsils. CD44 is a type 1 transmembrane glycoprotein also known as Phagocytic Glycoprotein-1 (pgp-1) and HCAM. CD44 is the receptor for hyaluronate and exists as a large number of different isoforms due to alternative RNA splicing. The major isoform expressed on lymphocytes, myeloid cells, and erythrocytes is a glycosylated type 1 transmembrane protein. Other isoforms contain glycosaminoglycans and are expressed on hematopoietic and non-hematopoietic cells. CD44 is involved in adhesion of leukocytes to endothelial cells, stromal cells, and the extracellular matrix. CD25: IL2 receptor alpha (IL2RA) and beta (IL2RB) chains, together with the common gamma chain (IL2RG), constitute the high-affinity IL2 receptor. Homodimeric alpha chains (IL2RA) result in low-affinity receptor, while homodimeric beta (IL2RB) chains produce a medium-affinity receptor. Normally an integral-membrane protein, soluble IL2RA has been isolated and determined to result from extracellular proteolyisis. Alternately-spliced IL2RA mRNAs have been isolated, but the significance of each is presently unknown. Mutations in this gene are associated with interleukin 2 receptor alpha deficiency.