title: [ABO blood group expression in corneal allograft failures].
abstract: BACKGROUND
  ABO blood group antigens are only expressed by the epithelial cells of normal human corneas. Since AB0 blood group antigens are also known to be expressed on stromal and endothelial cells of inflamed corneas, this study aimed to investigate the extend of ABO blood group antigen expression in corneal allograft failures.
  
  
  METHODS
  Twenty-two failed corneal allografts of 22 patients were examined. In 12 cases the patients had clinically proven corneal allograft rejection. In 10 cases there was no evident history of allograft rejection and the diagnosis graft failure due to chronic endothelial cell loss was made. Immunohistochemical staining of paraffin embedded sections was performed with monoclonal mouse antibodies to human blood group antigen A or B using the streptavidin-biotin-peroxidase complex technique.
  
  
  RESULTS
  Blood group antigens A or B were expressed by stromal keratocytes in 5 out of 12 and by endothelial cells in 7 out of 12 corneas with clinically proven immunologic graft rejection. Corneal transplants with chronic endothelial cell loss expressed blood group antigens A and/or B on the endothelial cells in three out of ten cases.
  
  
  CONCLUSIONS
  The results of this study show that ABO blood group antigens can be up-regulated in cases of corneal allograft failure, especially in cases of immune mediated graft rejection. This phenomenon might play a role in corneal allograft rejection.
authors.affiliation: Universitäts-Augenklinik, Medizinische Universität, Graz, Osterreich. navid.ardjomand@meduni-graz.at
authors.forename: N
authors.initials: N
authors.lastname: Ardjomand
authors.forename: P
authors.initials: P
authors.lastname: Komericki
authors.forename: A
authors.initials: A
authors.lastname: Klein
authors.forename: D
authors.initials: D
authors.lastname: Mattes
authors.forename: Y
authors.initials: Y
authors.lastname: El-Shabrawi
authors.forename: H
authors.initials: H
authors.lastname: Radner
mesh_terms: D000017:ABO Blood-Group System; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003315:Cornea / Q000166:cytology / Q000276:immunology; D016039:Corneal Transplantation / Q000276:immunology; D005260:Female; D006084:Graft Rejection / Q000276:immunology*; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D013997:Time Factors
chemical_list: D000017:ABO Blood-Group System