Collagen is the chief component of connective tissue, representing 30% of the protein in the human body. This protein may be target by a malfunctioning immune system. The set of diseases in which this occurs is known as collagen vascular disease.

A properly functioning immune system protects the body against infection, however, in cases of autoimmunity, including collagen vascular diseases, the immune system attacks the body’s own tissues. Antibodies may be targeted against antigens in the blood, skin, muscles and other organs, resulting in chronic inflammation and gradual degeneration of the affected tissues. As research into autoimmunity continues, the causal mechanisms are becoming better understood. Factors contributing to autoimmunity in general and collagen vascular diseases in particular include genetic make up, environmental factors and infection. Infectious agents may prime the immune system to attack structures in the body which they resemble. Proper treatment of these conditions requires prompt and accurate diagnosis. Laboratory studies supporting diagnosis include testing for anti-nuclear antibodies (ANA). This is particularly the case in Connective Tissue Disease, a subset of Collagen Vascular Disorders. Methods of ANA detection are detailed on the following pages.