98th Annual Meeting DOG 2000

S 472

Importance of MHC class II-antigens in high-risk keratoplasty

B. Nölle, N. Zavazava, E. Westphal, S. Jenisch, G. I. W. Duncker and Kiel-Cornea-Transplantation-Group

Purpose: Immune privilege of the cornea and anterior chamber is abrogated in high risk keratoplasties. Therefore, one could assume all HLA-antigens are relevant for corneal allograft rejections. Some studies show a clear importance of MHC-class I-antigens, but for MHC-class II-antigens data are still controversial, a final, generally accepted conclusion has not be drawn yet.

Study design: Since october 1-st 1993 a multicenter, randomized, prospective, double-blinded study to evaluate the relevance of MHC-class II-antigens in high risk penetrating keratoplasties with special respect to presensitization was started. EUROTRANSPLANT / Bio Implant Services, Leiden (NL) and "Deutsche Stiftung Organtransplantation" support the study. Major aspects of the study are: HLA-typing is allowed to be performed in only two laboratories with PCR-methods for MHC class II-antigens; graft diameter should be between 7 and 8 mm; systemic immunosuppression is not allowed; a treatment schedule and regular follow-up of at least 3 years have been established. For calculation of the graft numbers needed the following parameters were chosen: power 0.8; significance level 0.05; difference of graft rejection between test groups 10%; loss of patients 20%. The study control group should consist of 300 keratoplasties with optimal MHC class I-matching and class II-antigens offered at random. The verum group will consist of 300 keratoplasties with optimal matching for MHC class I- and II-antigens.

Results: Up to now 400 keratoplasties have been performed within the study. The study has not completed. 30 eye clinics of Germany support the project.

Discussion: Completion of the study will allow to evaluate the importance of MHC class II-antigens in high risk penetrating keratoplasties.

Universitäts-Augenklinik und Institut für Immunologie, Hegewischstr. 2, D-24105 Kiel