Immunological activity to different corneal antigens in patients with corneal diseases.

Patients suffering from various corneal diseases and waiting for keratoplasty have been immunologically investigated in order to establish sensitisation to corneal antigens. The presence of lymphocytes sensitised to the soluble from human corneas, bovine corneal epithelium, and bovine corneal stroma, which all possess common antigenicity, could be demonstrated in 30%, 50%, and 23%, respectively, of all patients. In none of these patients could a positive plasma antibody titre to human corneal antigens be detected. The results suggest the dominance of T-lymphocyte activity. No correlation was found between the degree of corneal vascularisation and the presence of sensitised lymphocytes to human corneal antigens. Arrangement of the patients according to diagnosis showed that especially those suffering from herpes simplex virus keratitis reacted positively to human corneal antigens. A possible explanation is given. Lymphocytes of controls showed no or only very low stimulation with the soluble fractions of human corneas or bovine corneal stromas. The soluble fraction of bovine corneal epithelium stimulated the lymphocytes of 6 out of 19 controls. The elimination of the donor corneal epithelium before transplantation may be beneficial in view of the involvement of histocompatibility antigens.