title: IgA rheumatoid factor in the sera and saliva of patients with rheumatoid arthritis and Sjögren's syndrome.
abstract: With a sensitive radioimmunoassay we have found elevated IgA rheumatoid factor (IgA-RF) levels in the sera of patients with rheumatoid arthritis, Sjögren's syndrome, and systemic lupus erythematosus. The IgA--RF showed a pattern of reaction with human IgG subclasses and animal gammaglobulins similar to that of IgM-RF from the same patients. Rheumatoid factors of both classes were shown to be present in saliva of patients with rheumatoid arthritis and Sjögren's syndrome.
mesh_terms: D001172:Arthritis, Rheumatoid / Q000276:immunology*; D003429:Cross Reactions; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis*; D007075:Immunoglobulin M / Q000032:analysis; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D011863:Radioimmunoassay; D012217:Rheumatoid Factor / Q000032:analysis*; D012463:Saliva / Q000276:immunology*; D012859:Sjogren's Syndrome / Q000276:immunology*
chemical_list: D007070:Immunoglobulin A; D007075:Immunoglobulin M; D012217:Rheumatoid Factor