Detection Method:Sandwich
Test principle:This assay employs a two-site sandwich ELISA to quantitate SIgA in samples. An antibody specific for SIgA has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and anySIgA present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for SIgA is added to the wells. After washing, Streptavidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of SIgA bound in the initial step. The color development is stopped and the intensity of the color is measured.
Product Overview:Secretory IgA (IgA) consists of two IgA monomers joined by the J-chain and furthermore a secretory component. It is secreted in plasma cells based in the lamina propia of mucosal membranes. Synthesis of IgA is independent from the synthesis of serum IgA. This means lack of serum IgA does not necessarily mean a lack of IgA.
IgA is found in secretions in a specific form called secretory IgA', Secretory IgA is the major immunoglobulin in saliva, tears, colostrum, nasal mucous, mother?s milk, tracheobronchial and gastrointestinal secretes. It plays a major role in preventing adherence of microorganisms to mucosal sites, in activation of the alternative complement pathway and in activating inflammatory reactions. Newborns are provided with IgA by mother?s milk and are passively immunized against gastrointestinal infections.
