The ImmuChrom Secretory IgA ELISA Kit is intended for the quantitative determination of sIgA in stool and saliva. This immunoassay allows an easy, rapid and precise quantification of secretory IgA. The kit includes all reagents ready to use for preparation of the samples.
Secretory IgA is comprised of two immunglobulin A molecules, which are joined by a J-protein and a secretory component. The secretory component is synthesized by epithelial cells of the mucous membrane of gastrointestinal, respiratory and urogenitaltract. It is also produced by the saliva, tear and mammary glands. The plasma cells in the subendothelial area of mucous membranes are releasing a complex of two IgA-molecules, which are joined over the J-protein. This complex is binding to a secretory component, located at the surface of the epithelia cell. After binding, the sIgA is transported across the cell and excreted by exocytosis. The determination of secretory IgA (sIgA) allows a first overview of the functionality of the gastrointestinal associated immune system (GALT). With this the secretory power and the degree of stimulation of the plasma cells of the intestinal submucosa is determined.
Sandwich ELISA, HRP-labelled antibody
secretory IgA, sIgA
Principle of Method
The sIgA-ELISA test determines human secretory IgA according to the “sandwich”-principle. sIgA in samples, standard and controls binds to antibodies, which are coated on the microtiterplate. After the washing step, a peroxidase labeled detection antibody is added. A second washing step is followed by the addition of the substrate which is converted to a colored product by the peroxidase. The reaction is terminated by the addition of an acidic stop solution. The optical densities are read at 450 nm (against the reference wavelength 620 nm) in a microtiterplate reader. The sIgA concentration can be calculated from the standard curve.
Stool: 100 mg (collected sample) in glass/plastic vials or ~20mg in stick vials
Saliva: 10 µl of centrifuged sample.
Calibration Range: 22.2 ng/ml - 600 ng/ml
Limit of Detection
Intra-assay (Within-Run) C.V.
Inter-assay (Run-to-Run) C.V.
Ilex Life Sciences LLC is an authorized distributor of Immuchrom GmbH products.