Recombinant Human CD4/LEU3 Protein (His Tag)

CD4 is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard phenotype marker for the identification of T cell populations. Mature human CD4 consists of a 371 amino acid extracellular region containing four immunoglobulin-like domains; a 22 aa transmembrane segment; and a 40 aa cytoplasmic domain. CD4 is expressed along with CD8 on double positive T cells during their development in the thymus. CD4 binds directly to MHC class II molecules on antigen presenting cells (10) . This interaction contributes to the formation of the immunological synapse which is focused around the TCR-MHC class II-antigenic peptide interaction. CD4 also functions as a chemotactic receptor for IL-16 and; in human; as a co-receptor for the gp120 surface glycoprotein of HIV-1.

Generally, lyophilized proteins are stable for up to 12 months when stored at -20 to -80°C. Reconstituted protein solution can be stored at 4-8°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.