title: Tolerance to incompatible ABO blood group antigens is not observed following homograft implantation.
abstract: Failure to develop antibodies to nonself A and B blood group antigens is well described after infant ABO-incompatible heart transplantation and suggests that exposure to incompatible ABO antigens early in life may lead to tolerance rather than immunogenicity. If this finding is also true following ABO-incompatible cryopreserved homograft implantation, then such patients who require transplantation may be able to accept certain ABO-incompatible organs. In this study, we measured anti-A and -B antibody titers (isohemagglutinins) and allosensitization to human leukocyte antigens (HLA) in 21 patients after homograft placement (12 of whom were <1 year of age at initial homograft exposure) in childhood. We also examined homograft explant specimens for endothelial preservation and expression of HLA and A and B blood group antigens. We observed no differences in isohemagglutinins between patients who received ABO-incompatible versus ABO-compatible homografts. Allosensitization to HLA was present in 88% of patients (9 of 9 ABO-incompatible recipients and 5 of 7 ABO-compatible recipients). In 7 homograft explant specimens (median implant duration 10.1 years), the vasa vasorum endothelium was intact with ABO blood group antigen expression on 3 of 5 non-O homografts. These data suggest that tolerance to incompatible A and B blood group antigens does not occur following placement of ABO-incompatible homografts in childhood.
authors.affiliation: Pediatric Cardiology, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, PA 15224, USA. brian.feingold@chp.edu
authors.forename: Brian
authors.initials: B
authors.lastname: Feingold
authors.forename: Jay S
authors.initials: JS
authors.lastname: Raval
authors.forename: Csaba
authors.initials: C
authors.lastname: Galambos
authors.forename: Mark
authors.initials: M
authors.lastname: Yazer
authors.forename: Adriana
authors.initials: A
authors.lastname: Zeevi
authors.forename: Carol
authors.initials: C
authors.lastname: Bentlejewski
authors.forename: Victor O
authors.initials: VO
authors.lastname: Morell
authors.forename: Peter D
authors.initials: PD
authors.lastname: Wearden
authors.forename: Steven A
authors.initials: SA
authors.lastname: Webber
mesh_terms: D000017:ABO Blood-Group System / Q000276:immunology*; D000328:Adult; D001011:Aorta / Q000002:abnormalities / Q000276:immunology* / Q000601:surgery; D001787:Blood Group Incompatibility / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006084:Graft Rejection / Q000276:immunology*; D006680:HLA Antigens / Q000276:immunology; D006388:Hemagglutinins / Q000097:blood / Q000276:immunology; D006801:Humans; D007108:Immune Tolerance; D007223:Infant; D007518:Isoantibodies / Q000097:blood / Q000276:immunology; D008297:Male; D011651:Pulmonary Artery / Q000002:abnormalities / Q000276:immunology* / Q000601:surgery; D012189:Retrospective Studies; D014184:Transplantation, Homologous; D019737:Transplants; D014481:United States
chemical_list: D000017:ABO Blood-Group System; D006680:HLA Antigens; D006388:Hemagglutinins; D007518:Isoantibodies