[An immunohistochemical study of cornea and adjacent bulbar conjunctiva in Mooren's ulcer]

The specimens of the corneal lesions and their adjacent bulbar conjunctivas taken from 14 cases with Mooren's ulcers were studied by immunohistochemical techniques to investigate the expression of HLA-DR antigen and the subgroups of lymphocytes. It is discovered that there is an aberrant expression of HLA-DR antigen in a large amount of keratoconjunctival epithelial cells and stromal keratocytes and simultaneously, the CD4/CD8 ratio is significantly higher than that of the normal control group. The results suggest that the aberrant expression of MHC-II antigen in the resident cells at the peripheral cornea and its adjacent conjunctiva and a raised local TH/TS ratio leading to an excessive autoimmune reactivity be possibly the direct cause of the pathogenesis of the Mooren's ulcer.