title: cPRA Increases With DQA, DPA, and DPB Unacceptable Antigens in the Canadian cPRA Calculator.
abstract: A calculated panel reactive antibody (cPRA) estimates the percentage of donors with unacceptable antigens (UA) for a recipient. cPRA may be underestimated in transplant candidates with UA to DQA, DPA, and DPB if these are not included in the calculation program. To serve the National Canadian Transplant Programs, a cPRA calculator was developed with complete molecular typing for all donors at HLA-A, B, C, DRB1, DRB3/4/5, DQA1, DQB1, DPA1, and DPB1, all resolved to serologic equivalents. The prevalence of UA at DQA, DPA and DPB was evaluated in a sensitized regional population. The impact of adding these additional UA to cPRA was calculated alone and in combination, and compared to the baseline cPRA for UA at A, B, C, DR, DR51/52/53, and DQ. Of 740 sensitized transplant candidates, 18% of total and 32% with cPRA≥95% had DQA UA. Twenty-seven percent of total and 54% with cPRA≥95% had DPB UA. Of 280/740 subjects with these UA, 36/280 (13%) had cPRA increase of >20% when they were included, 7% increased cPRA to ≥80% and 6% to ≥95%. Inclusion of DQA, DPA, and DPB UA in Canadian cPRA calculations improves the accuracy of cPRA where these are relevant in allocation.
authors.affiliation: Division of Nephrology, Department of Medicine and HLA Laboratory, University Health Network, University of Toronto, Toronto, Ontario, Canada.|Canadian Blood Services, Organ and Tissue Donation and Transplantation, Ottawa, Ontario, Canada.
authors.forename: K J
authors.initials: KJ
authors.lastname: Tinckam
authors.affiliation: Department of Pathology and Laboratory Medicine, Dalhousie University, Nova Scotia, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Liwski
authors.affiliation: Transplant Immunology Laboratory, Diagnostic Services Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: D
authors.initials: D
authors.lastname: Pochinco
authors.affiliation: Canadian Blood Services, Organ and Tissue Donation and Transplantation, Ottawa, Ontario, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Mousseau
authors.affiliation: Canadian Blood Services, Organ and Tissue Donation and Transplantation, Ottawa, Ontario, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Grattan
authors.affiliation: Canadian Blood Services, Organ and Tissue Donation and Transplantation, Ottawa, Ontario, Canada.|Transplant Immunology Laboratory, Diagnostic Services Manitoba, Winnipeg, Manitoba, Canada.|Section of Nephrology, Department of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Nickerson
authors.affiliation: Division of Medicine and Laboratory Medicine, University of Alberta, Edmonton, Alberta, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Campbell
mesh_terms: D000465:Algorithms; D006682:HLA-DP Antigens / Q000276:immunology*; D006683:HLA-DQ Antigens / Q000276:immunology*; D006684:HLA-DR Antigens / Q000276:immunology*; D006650:Histocompatibility Testing; D006801:Humans; D007518:Isoantibodies / Q000097:blood* / Q000276:immunology; D016377:Organ Transplantation; D010641:Phenotype; D011379:Prognosis
chemical_list: D006682:HLA-DP Antigens; D006683:HLA-DQ Antigens; D006684:HLA-DR Antigens; D007518:Isoantibodies
keywords: Alloantibody; alloantigen; immunogenetics; panel reactive antibody (PRA)