Test Principle ImmunoCAP Specific IgG4

The ImmunoCAP Specific IgG4 assay is based upon the proven ImmunoCAP cellulose solid phase.  The ImmunoCAP solid phase consists of a three dimensional cellulose derivative, encased in a capsule, allowing for discrete, automated assay processing.  This classic “sandwich” immunoassay, by utilizing the cellulose solid phase, allows for the covalent binding of large amounts of the antigen of interest.  The cellulose matrix also makes it possible for the instrument to perform a thorough washing between sample and reagent additions, thus accounting for the observed low background signals.

 

The antigen of interest, covalently coupled to the solid phase, reacts with the specific IgG4 antibodies in the patient sample.
After washing away non-specific IgG4 antibodies, enzyme labelled antibodies against IgG4 are added to form a complex.
After incubation, unbound enzyme-anti-IgG4 is washed away and the bound complex is then incubated with a developing agent.
After stopping the reaction, the fluorescence of the eluate is measured. The higher the fluorescence, the more specific IgG4 antibodies are present in the sample.