Description
Principle of the assay: human MDC ELISA Kit was based on standard sandwich enzyme-linked immune-sorbent assay technology. A monoclonal antibody from mouse specific for MDC has been precoated onto 96-well plates. Standards(E.coli, G25-Q93) and test samples are added to the wells, a biotinylated detection polyclonal antibody from goat specific for MDC is added subsequently and then followed by washing with PBS or TBS buffer. Avidin-Biotin-Peroxidase Complex was added and unbound conjugates were washed away with PBS or TBS buffer. HRP substrate TMB was used to visualize HRP enzymatic reaction. TMB was catalyzed by HRP to produce a blue color product that changed into yellow after adding acidic stop solution. The density of yellow is proportional to the human MDC amount of sample captured in plate.
Background: Macrophage-derived chemokine (MDC), also called Chemokine, cc motif, ligand 22 (CCL22) or Small inducible cytokine subfamily A, member 22 (SCY22). MDC is a recently identified member of the CC chemokine family. It is not closely related to other chemokines, sharing most similarity with thymus- and activation-regulated chemokine (TARC), which contains 37% identical amino acids. In addition, MDC gene is mapped to chromosome 16q13, the same position reported for the TARC gene. MDC has the four-cysteine motif and other highly conserved residues characteristic of CC chemokines, but it shares <35% identity with any of the known chemokines. Recombinant MDC was expressed in Chinese hamster ovary cells and purified by heparin-Sepharose chromatography. MDC is highly expressed in macrophages and in monocyte-derived dendritic cells, but not in monocytes, natural killer cells, or several cell lines of epithelial, endothelial, or fibroblast origin. High expression was also detected in normal thymus and less expression in lung and spleen. MDC is thus a unique member of the CC chemokine family that may play a fundamental role in the function of dendritic cells, natural killer cells, and monocytes