Patent ID: 7993866

Claim:
A method for performing an assay for improving the diagnosis of Crohn's disease, said method comprising: (a) contacting a patient's sample containing IgA anti-outer membrane protein antibodies (anti-OmpC antibodies) with an OmpC antigen, or reactive fragment thereof to form a complex between the OmpC antigen or reactive fragment thereof and the IgA anti-OmpC antibodies; (b) contacting the sample from step (a) with an enzyme-labeled anti-IgA antibody to form a labeled complex; (c) contacting the sample from step (b) containing a labeled complex with an enzyme substrate; and (d) analyzing the sample from step (c) for the presence or absence of the labeled complex using a spectrophotometer, wherein the analysis detects the labeled complex, to improve the diagnosis of Crohn's disease.