The IDK® sIgA ELISA is an enzyme immunoassay intended for the quantitative determination of secretory IgA (sIgA) in saliva and stool.

FDA Class 1 Exempt. For In Vitro Diagnostic Use. Health Canada Licensed.

For Laboratory Professional Use Only.

Fecal sIgA is the most abundant class of antibodies found in the intestinal lumen. The immune tolerance of the intestinal mucosa can be evaluated using the concentration of fecal secretory IgA. A deficiency of sIgA points to diminished activity of the mucosa immune system, whereas increased sIgA values indicate increased activity and local inflammation of the intestinal mucosa.

The IDK® sIgA ELISA is compatible with our IDK Extract® Stool Sample Preparation System.

The IDK® sIgA ELISA is also available in a customized bulk pack (20 plates) if your lab is testing at high volumes.

Developed by Immundiagnostik AG.

Test Principle of the IDK® sIgA ELISA

In the first incubation step, the sIgA in the samples is bound to polyclonal antibodies (rabbit anti-human IgA), which are immobilized to the surface of the microtiter wells. To remove all unbound substances, a washing step is carried out.

In the second incubation step, a peroxidase-labeled conjugate (mouse anti-sIgA) is added, specifically recognizing the bound secretory IgA. After another washing step to remove all unbound substances, the solid phase is incubated with a tetramethylbenzidine (TMB) substrate. An acidic stop solution is then added to stop the reaction. The color converts from blue to yellow. The intensity of the yellow color is directly proportional to the concentration of secretory IgA.

A dose-response curve of the absorbance unit (optical density, OD) vs. concentration is generated using the results obtained from the standards. The presence of secretory IgA in the patient samples is determined directly from this curve.