title: HLA-A, HLA-B and HLA-DR matching reduces the rate of corneal allograft rejection.
abstract: OBJECTIVE
  The purpose of this study is to determine the effectiveness of HLA typing in preventing corneal allograft rejection.
  
  
  METHODS
  This retrospective single-center study analyzed 459 consecutive HLA-typed patients who underwent perforating keratoplasty (PKP) between 1983 and 2001. Grafts were postoperatively transparent after donor-recipient selection by HLA-A, -B and -DR typing. Patients were divided into a low- and a high-risk group based on their preoperative diagnosis.
  
  
  RESULTS
  The estimated 1-, 5- and 10-year graft survival (Kaplan-Meier) was 93, 88 and 67% in low-risk patients and 73, 43 and 38% in high-risk patients. We found a significant correlation between the number of HLA mismatches and the rate of allograft rejections: a donor-recipient match of two or more alleles in HLA-A, -B or -DR reduces the rejection rate by at least 10% in low-risk (10 years after PKP; P<0.04) and 40% in high-risk patients (3 years after PKP; P<0.0001). Especially HLA-B mismatches are important prognostic factors for both low- ( P<0.008) and high-risk patients ( P<0.003). Considering both HLA-B and -DR mismatches significantly reduces the rate of allograft rejection, particularly in high-risk patients ( P<0.0001). Matching on a split typing level offers no significant advantage over broad level matching.
  
  
  CONCLUSIONS
  Clinical results confirm theories developed to explain the function of the HLA (MHC) receptor. The closest possible donor-recipient match of HLA antigens based on broad level typing significantly reduces the rate of allograft rejection and thus improves the prognosis for long-term transparency of corneal grafts in both high- and low-risk patients.
authors.affiliation: Department of Ophthalmology, Charité University Medicine Berlin, Benjamin Franklin Campus, Hindenburgdamm 30, 12200 Berlin, Germany. riad.khaireddin@gmx.com
authors.forename: Riad
authors.initials: R
authors.lastname: Khaireddin
authors.forename: Joachim
authors.initials: J
authors.lastname: Wachtlin
authors.forename: Werner
authors.initials: W
authors.lastname: Hopfenmüller
authors.forename: Friedrich
authors.initials: F
authors.lastname: Hoffmann
mesh_terms: D003315:Cornea / Q000276:immunology*; D015925:Cryopreservation; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000517:prevention & control*; D006085:Graft Survival / Q000502:physiology; D015234:HLA-A Antigens / Q000276:immunology*; D015235:HLA-B Antigens / Q000276:immunology*; D006684:HLA-DR Antigens / Q000276:immunology*; D006650:Histocompatibility Testing; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D015948:Keratoplasty, Penetrating / Q000276:immunology*; D009926:Organ Preservation; D012189:Retrospective Studies; D014184:Transplantation, Homologous
chemical_list: D015234:HLA-A Antigens; D015235:HLA-B Antigens; D006684:HLA-DR Antigens; D007166:Immunosuppressive Agents