title: Profiling antibodies to class II HLA in transplant patient sera.
abstract: Immunizing events including pregnancy, transfusions, and transplantation promote strong alloantibody responses to HLA. Such alloantibodies to HLA preclude organ transplantation, foster hyperacute rejection, and contribute to chronic transplant failure. Diagnostic antibody-screening assays detect alloreactive antibodies, yet key attributes including antibody concentration and isotype remain largely unexplored. The goal here was to provide a detailed profile of allogeneic antibodies to class II HLA. Methodologically, alloantibodies were purified from sensitized patient sera using an HLA-DR11 immunoaffinity column and subsequently categorized. Antibodies to DR11 were found to fix complement, exist at a median serum concentration of 2.3μg/mL, consist of all isotypes, and isotypes IgG2, IgM, and IgE were elevated. Because multimeric isotypes can confound diagnostic determinations of antibody concentration, IgM and IgA isotypes were removed and DR11-IgG tested alone. Despite removal of multimeric isotypes, patient-to-patient antibody concentrations did not correlate with MFI values. In conclusion, allogeneic antibody responses to DR11 are comprised of all antibody isotypes at differing proportions, these combined isotypes fix complement at nominal serum concentrations, and enhancements other than the removal of IgM and IgA multimeric isotypes may be required if MFI is to be used as a means of determining anti-HLA serum antibody concentrations in diagnostic clinical assays.
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Curtis
authors.initials: C
authors.lastname: McMurtrey
authors.affiliation: University of Warwick, Coventry, United Kingdom; NHSBT Birmingham, Birmingham, United Kingdom.
authors.forename: Dave
authors.initials: D
authors.lastname: Lowe
authors.affiliation: Pure Protein LLC, Oklahoma City, OK, United States.
authors.forename: Rico
authors.initials: R
authors.lastname: Buchli
authors.affiliation: University of Warwick, Coventry, United Kingdom; University Hospitals of Coventry & Warwickshire NHS Trust, Coventry, United Kingdom.
authors.forename: Sunil
authors.initials: S
authors.lastname: Daga
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Derek
authors.initials: D
authors.lastname: Royer
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Alisha
authors.initials: A
authors.lastname: Humphrey
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Steven
authors.initials: S
authors.lastname: Cate
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Sean
authors.initials: S
authors.lastname: Osborn
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Mojsilovic
authors.affiliation: Pure Protein LLC, Oklahoma City, OK, United States.
authors.forename: Rodney
authors.initials: R
authors.lastname: VanGundy
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Bardet
authors.affiliation: The Icahn School of Medicine at Mount Sinai, New York City, NY, United States.
authors.forename: Andrew
authors.initials: A
authors.lastname: Duty
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Danijela
authors.initials: D
authors.lastname: Mojsilovic
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Jackson
authors.affiliation: University of Texas Southwestern Medical Center, Dallas, TX, United States.
authors.forename: Peter
authors.initials: P
authors.lastname: Stastny
authors.affiliation: NHSBT Birmingham, Birmingham, United Kingdom.
authors.forename: David
authors.initials: D
authors.lastname: Briggs
authors.affiliation: University of Warwick, Coventry, United Kingdom; University Hospitals of Coventry & Warwickshire NHS Trust, Coventry, United Kingdom.
authors.forename: Daniel
authors.initials: D
authors.lastname: Zehnder
authors.affiliation: University Hospitals of Coventry & Warwickshire NHS Trust, Coventry, United Kingdom.
authors.forename: Rob
authors.initials: R
authors.lastname: Higgins
authors.affiliation: University of Oklahoma Health Science Center, Oklahoma City, OK, United States; Pure Protein LLC, Oklahoma City, OK, United States. Electronic address: William-hildebrand@ouhsc.edu.
authors.forename: William
authors.initials: W
authors.lastname: Hildebrand
mesh_terms: D000328:Adult; D000368:Aged; D000920:Antibody-Dependent Cell Cytotoxicity; D002460:Cell Line; D002846:Chromatography, Affinity; D003165:Complement System Proteins / Q000378:metabolism; D005260:Female; D006084:Graft Rejection / Q000175:diagnosis / Q000209:etiology / Q000276:immunology*; D059811:HLA-DRB1 Chains / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000097:blood / Q000276:immunology / Q000302:isolation & purification*; D007136:Immunoglobulins / Q000097:blood / Q000276:immunology / Q000302:isolation & purification*; D007159:Immunologic Tests; D007519:Isoantigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D019076:Transgenes / Q000235:genetics; D014180:Transplantation; D055815:Young Adult
chemical_list: D059811:HLA-DRB1 Chains; C509455:HLA-DRB1*11:01 antigen; D007132:Immunoglobulin Isotypes; D007136:Immunoglobulins; D007519:Isoantigens; D003165:Complement System Proteins