Effect of interferon-alpha on MHC expression and influx of inflammatory cells on the rat eye

Interferon-alpha can be used as additional treatment of herpes keratitis. However, several studies have demonstrated that interferon-alpha can induce immunological changes in several tissues, and if used in a patient with a corneal transplantation, those changes might induce rejection of the corneal transplant. In order to determine the immunological changes in corneal tissue, we examined the effect of local treatment with interferon-alpha on MHC Class I and II expression, and inflammatory cell influx in the rat eye, and compared this with the changes induced by intrastromal sutures. These changes were evaluated by immunohistology for MHC Class I and II and several immunologically active cells. Intrastromal sutures induced an influx of lymphocytes and macrophages and induction and/or upregulation of MHC Class I and II. Local treatment with interferon-alpha did not have any of these effects. We conclude that topical use of interferon-alpha is not likely to induce rejection of a corneal graft.