title: Anti-HLA class II antibodies in kidney retransplant patients.
abstract: The relevance of anti-HLA class II antibodies for kidney graft survival is still controversial. In part, this can be attributed to difficulties to detect and differentiate anti-HLA class II antibodies. Anti-HLA class II IgG antibody screening was performed by enzyme-linked immunosorbent assay. Subsequently, all anti-HLA class II-positive sera were subjected to the determination and specification using color-coded microspheres coated with purified HLA antigens. In a cohort of 934 patients awaiting kidney transplantation, 41 sera (4.4%) were positive for IgG anti-HLA class II antibodies. The presence was confirmed in 90.2% sera by retesting. Subsequently, all anti-HLA class II-positive patients (n = 27) who in the past had undergone a kidney transplantation with an HLA-DR and/or -DQ-mismatched graft were selected. In 25 of 27 sera (92.6%), the alloantibody specificities corresponded to the known previous transplant mismatches on a broad antigen level. In 20 of 27 sera (74.1%), anticlass I antibodies were detected as well. Anti-HLA-DP antibodies were seen in 24 of the 27 sera of this cohort. In the majority of the cases, the reactivities with different DPB1 alleles could be explained by involvement of a single, specific DPB1 epitope. Donor-specific anti-HLA-DR and -DQ antibodies were seen in the majority of cases with graft failure following HLA class II alloantigen exposure in prior kidney transplantations. In addition, HLA-DP may serve as a transplantation antigen in kidney transplantation, leading to a humoral response.
authors.affiliation: Institute for Clinical Immunology and Department of Medicine, University of Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: M-L
authors.initials: ML
authors.lastname: Arnold
authors.forename: R
authors.initials: R
authors.lastname: Pei
authors.forename: B
authors.initials: B
authors.lastname: Spriewald
authors.forename: R
authors.initials: R
authors.lastname: Wassmuth
mesh_terms: D004797:Enzyme-Linked Immunosorbent Assay; D006681:HLA-D Antigens / Q000276:immunology*; D006801:Humans; D007518:Isoantibodies / Q000276:immunology*; D016030:Kidney Transplantation; D012086:Reoperation; D014019:Tissue Donors
chemical_list: D006681:HLA-D Antigens; D007518:Isoantibodies