An enzyme linked immunosorbent assay for detection of anti-aorta antibodies in Takayasu arteritis patients.

Thirty cases of clinically and angiographically proven non-specific aortoarteritis with appropriate controls were studied. Antiaorta antibody titres were estimated using enzyme linked immunosorbent assay (ELISA) method. The controls included patients of vascular diseases other than non-specific aortoarteritis, autoimmune diseases (rheumatoid arthritis and systemic lupus erythematosis), and normal healthy individuals. An absorbance value at 492 nm at a dilution of 1:500 of patients' sera was expressed as the antiaorta antibody titre. There was a significant difference (P < 0.005) between the mean value of the antibody titre of non-specific aortoarteritis patients (0.471 +/- 0.073) and patients of other vascular diseases (0.209 +/- 0.056), autoimmune disease patients (0.143 +/- 0.024) and controls (0.108 +/- 0.012). Collagenase treatment of the aorta resulted in the fall of the antibody titre of aortitis patients (0.162 +/- 0.036) suggesting that the collagen might be one of the components responsible for autoantigenecity of the aorta resulting in aortitis. The precise nature of the antigen needs to be identified.