CD133 (Prominin-1) Monoclonal Antibody (EMK08), FITC, eBioscience™, Invitrogen™

Description

The EMK08 monoclonal antibody reacts with human CD133 (Prominin-1), a 120 kDa member of the pentaspan family of proteins, which also includes Prominin-2. Their expression is found within plasma membrane protrusions such as epithelial microvilli. CD133 can exist in a number of alternatively spliced isoforms, and the protein has several N-linked glycosylation sites; the occurrence of both may be tissue-dependent. Human CD133 was first identified as an epitope expressed on CD34+ hematopoietic progenitors. Although the ligand and function of CD133 remain unknown, it has since proven to be very useful as a marker for both stem cells and cancer stem cells. In addition to its expression on hematopoietic precursors, CD133 has been used to identify tumorigenic colon cancer stem cells, brain cancer stem cells, prostate cancer stem cells, in addition to others. The binding of the EMK08 antibody does not block the binding of another anti-human CD133 antibody, TMP4 (cat. 12-1338) indicating that they recognize distinct epitopes. This EMK08 antibody has been pre-titrated and tested by flow cytometric analysis of normal human peripheral blood cells. 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. Filtration: 0.2 μm post-manufacturing filtered.

The CD133 (AC133) antigen is a 97 kDa glycoprotein, with 5 transmembrane domains, that shows up as a 120 kDa band on protein gels due to glycosylation. CD133 is a cell surface marker expressed by immature hematopoietic stem cells but not mature blood cells. In addition to hematopoietic stem and progenitor cells, CD133 has been found to be a marker for other stem and progenitor cells including neural and embryonic stem cells. CD133 has been shown to be expressed in cancers, including some leukemias and brain tumors, that may be derived from stem cells. Low level expression could also be detected in the kidney, pancreas, placenta, and fetal liver. Mutations in this gene have been shown to result in retinitis pigmentosa and Stargardt disease. Expression of the CD133 gene is also associated with several types of cancer. CD133 is expressed from at least five alternative promoters that are expressed in a tissue-dependent manner, and multiple transcript variants encoding different isoforms have been found.