Changes in tear protein composition in Graves' ophthalmopathy

Abstract

The tear protein composition of normal volunteers and that of patients suffering from hyperthyroidism and various degrees of infiltrative endocrine ophthalmopathy were studied by polyacrylamide-gel electrophoresis, radial immunodiffusion and laser nephelometry. Increased level of IgG, serum albumin and transferrin was demonstrated in hyperthyroidism and severe infiltrative ophthalmopathy. Elevated IgA, IgM and immune complex (IC) levels were detected in cases with mild and severe infiltrative ophthalmopathy, which showed good correlation with the severity of the disease. A decrease in the level of tear specific proteins showed the dysfunction of the lacrimal glands in long-standing cases of Graves' ophthalmopathy. Elevated immunoglobulin levels in cases with irritation are partly the result of increased vascular permeability. High IgA, IgM and 1C levels observed without permeability changes in mild ophthalmopathy suggest the local production of immunoglobulins in infiltrative ophthalmopathy and their possible role in the development of the eye manifestations of Graves' disease. The use of tear protein determinations in the diagnosis and in the evaluation of different therapeutic procedures is discussed.

Key Words:

• tear protein composition
• Graves' ophthalamopathy
• immunoglobulins
• immune complexes
• permeability changes
• local immunological reactions