Expression of thyrotropin-receptor mRNA in healthy and Graves' disease retro-orbital tissue

It is not clear whether the ophthalmopathy present in Graves' disease is related to autoimmune reactions to common thyroid/orbit components or is due to specific ocular antigens unrelated to the thyroid. In Graves' disease, serum antibodies to the thyrotropin receptor (TSH-R) can stimulate thyroid function, but no link between the TSH-R and ocular tissues has been found. We have shown, by polymerase chain reaction amplification of specific cDNA, that mature TSH-R mRNA is expressed in the retro-orbital tissue of both healthy subjects and patients with Graves' disease. Of other tissues and cells tested (fibroblasts, lymphocytes, muscle, and thyroid), only thyroid tissue expressed the TSH-R mRNA.