RETRO-ORBITAL AUTOIMMUNITY

What causes Graves' ophthalmopathy is still a mystery, but the disease process results from a complex interplay of genetic and environmental factors. Genes such as those encoding for human leukocyte antigens, c ytokines or putative target antigens may determine a patient's suscept ibility to the disease and the disease severity, but environmental fac tors may determine its course, During the last 5 years, significant pr ogress has been made towards a more in-depth understanding of the init iating events of the orbital immune process which occur in the context of autoimmune thyroid disease. Once established, the chronic inflamma tory process within the orbital tissues appears to take on a momentum of its own. The work of many investigators has recently helped to exte nd our knowledge about the effector and target cells, and their recipr ocal interaction, in the evolution and perpetuation of the orbital imm une process. This chapter's focus is on the more recent aspects of ret ro-orbital autoimmunity, discussing new developments concerning orbita l T-cell repertoires, candidate orbital antigens, potential target and effector cells, and their role in the extrathyroidal manifestations o f autoimmune thyroid disease.