Immunopathology of vitreous and retinochoroidal biopsy in posterior uveitis.

The authors used immunopathologic techniques to study vitreous and/or retinochoroidal biopsies from 23 patients with posterior uveitis unresponsive to conventional therapy or who had developed significant complications despite therapy. Results indicated that during active uveitis from many causes, T-helper cells predominated in the vitreous and retinochoroidal biopsies. Monocytes were not prominent constituents except in several cases of granulomatous etiology (e.g., syphilis and acute retinal necrosis). Class II major histocompatibility complex (MHC) antigens were increased on the retinal vascular endothelium, implicating an important role for these cells in the local cellular immune response. These results may be of great importance in our understanding of uveitis, as well as being helpful in categorizing posterior uveitis, permitting appropriate therapy to be given.