Signosis’ Autoimmune ELISA Kits detect autoimmune antibodies in human serum using a standard ELISA format. A specific antigen is pre-coated onto microtiter wells to capture the target antibodies. During the assay, the sample is added, and autoimmune antibodies, if present, bind to the immobilized antigen.

An HRP-conjugated anti-human IgG antibody is then added, forming a complex. After washing away unbound components, a substrate is added. HRP catalyzes a color change—turning blue, then yellow after Stop Solution is added. The intensity of the yellow color, measured at 450 nm, is directly proportional to the concentration of autoimmune antibodies in the sample.