Serum glycoproteins in autoimmune diseases

The concentration of IgA, IgG, IgM, coeruloplasmin, alpha-2-macroglobulin, beta-1-C-globulin, transferrin as well as of alpha-2-haptoglobin, orosomucoid and haemopexin has been studied in the serum of patients with disseminated lupus erythematosus, chronic progressive polyarthritis and immunopathological syndromes. The concentration of the carbohydrate components bound to serum proteins was also determined. In disseminated lupus erythematosus, the concentration of IgA, IgG, IgM, coeruloplasmin, and hexose, hexosamine and sialic acid bound to proteins, as well as of seromucoid was increased. In chronic progressive polyarthritis the IgA, IgG, IgM, coeruloplasmin, alpha-2-macroglobulin and beta-1-C-globulin concentration and the carbohydrate components bound to serum proteins rose. In immunopathological syndromes, too, the serum IgA, IgG, IgM, coeruloplasmin, and protein-bound hexosamine and sialic acid levels were increased. Under the effect of treatment, the elevated glycoprotein concentrations usually decrease, but the level of carbohydrate components bound to serum proteins hardly changes. The pathogenic and diagnostic significance of serum glycoproteins is discussed.