Chapter 84 – Anticollagen Antibodies

Collagen is a triple-helical molecule, which functions as the major scaffold protein in tissues and participates in cell–matrix interactions. Its deposition in the extracellular compartment renders it an immunogen and a target for attack by autoantibodies in susceptible individuals. Several types of collagens have been described as the target of autoantibodies in autoimmune diseases, and the clinical features of the ensuing disease reflect the organ location of the specific collagen. Collagens that are implicated in autoimmunity include types I, II, III, V (e.g., adult and juvenile rheumatoid arthritis (RA)), type IV (Goodpasture syndrome), types VII and XVII (immunobullous diseases), and type XIII (Graves’ disease). In some cases, the causative role of antibodies has been clearly established in animal models. In everyday clinical practice, identification of anticollagen antibodies in the appropriate setting may help the clinician in establishing an accurate diagnosis and in predicting the prognosis.