Immune complexes and autoantibodies in patients with giant cell arteritis and their relationship with autologous rosette-forming cells.

Serologic studies and lymphocyte analysis were carried out in 29 patients with giant cell arteritis (GCA). IgA-containing circulating immune complexes (CIC) were detected in 16 GCA patients with or without polymyalgia rheumatica (55%). A significant difference was demonstrated in autologous rosette-forming cells between the patients as a whole, and matched controls (8.6 +/- 2.0 vs 11.6 +/- 2.4, p less than 0.001), and also between patients with and patients without CIC (7.9 +/- 1.6 vs 9.4 +/- 2.0, p less than 0.001).