Histocompatibility antigen and passenger cell content of normal and diseased human cornea.

The outcome of clinical corneal transplantation depends on the degree of vascularization and inflammation present in the graft bed at the time of the operation, but the reason for this is unclear. Normal, diseased, and rejected human corneas have been examined with an immunoperoxidase staining procedure, employing monoclonal antibodies to class I and II major histocompatibility complex (MHC) antigens and to other leukocyte markers. In particular, departures from normal in the expression of MHC antigens and in the passenger cell distribution in the diseased or rejected corneas were sought. MHC antigen expression did not alter with inflammation, vascularization, or rejection. However, dendritic-like passenger cells, which were found in low numbers throughout the central stroma of normal cornea as well as in basal epithelium, significantly increased in number in vascularized corneas. We suggest that the breakdown of corneal privilege in vascularized eyes may reflect the increased number of accessory cells in the graft bed.

Leukocytes in the graft bed associated with corneal graft failure. Analysis by immunohistology and actuarial graft survival.

Immunohistochemical staining analysis using monoclonal antibodies was performed on 107 recipient corneas removed at graft. There were significantly more infiltrating cells bearing one or more of the leukocyte-common antigen, class II major histocompatibility complex antigens, various myeloid-lineage markers, and a peripheral T cell marker, in the graft beds of those recipients who subsequently lost a corneal graft than there were in the graft beds of those for whom the outcome was successful. The hypothesis that large numbers of leukocytes in the recipient graft bed would be correlated with subsequent graft failure was examined by actuarial graft survival analysis. Recipients whose corneas contained fewer than 50 leukocyte-common antigen-positive cells/mm2 of corneal stroma showed a 3-year actuarial graft survival of 83%, compared with 39% in those whose corneas contained more than 50 such cells/mm2. The corneal leukocyte count was a particularly useful prognostic indicator of outcome in those patients judged clinically to be at risk of graft failure.

Long-term outcome after corneal transplantation. Visual result and patient perception of success.

Snellen acuity, reading line, and keratometry were measured in a cohort of 60 patients at 2 or more years after penetrating keratoplasty was performed. Patients were asked to complete a questionnaire to elicit information on their perceptions of visual function and the success of the procedure. Using preferred correction, a Snellen acuity of 6/18 or better was achieved by 65%, and a reading line of N8 or better was achieved by 57% of index grafts. Thirty-eight percent had more than 5 diopters (D) of astigmatism in the graft. Approximately 75% of patients reported satisfaction with their graft (satisfaction being associated with better acuity in the grafted eye than the other eye), graft clarity, and a perceived improvement in lifestyle. Dissatisfaction appeared to be associated with graft failure and problems with contact lens wear. The findings have implications for patient selection for corneal transplantation and for the measurement of outcome.