Immunology Diagnosis

A study published last year by the team at LUMC in Proceedings of the National Academy of Sciences showed that IgG and IgA antibodies recognizing carbamylated antigens were present in about 50% of RA patients. Anti-CarP antibodies recognize homocitrulline and are therefore distinct from anti-citrullinated protein antibodies (ACPA), including anti-Cyclic Citrullinated Peptide (anti-CCP), a biomarker commonly used to diagnose RA. Anti-CarP IgG and IgA were detected in 16% and 30% of ACPA negative RA patients respectively. Additionally, anti-CarP antibodies were shown to be predictive of a more severe course of disease as measured by radiological progression in ACPA negative RA patients.2,3