title: Histopathologic changes in anti-angiotensin II type 1 receptor antibody-positive kidney transplant recipients with acute rejection and no donor specific HLA antibodies.
abstract: OBJECTIVE
  To determine the association of antibodies against angiotensin II type 1 receptor (AT1R Ab) and histopathologic changes seen in patients with kidney allograft rejection and negative donor specific HLA antibodies (DSA).
  
  
  METHODS
  Stored sera from 27 patients who had biopsy-proven rejection in the absence of DSA were tested for AT1R Ab. Biopsy slides of all patients were re-examined and classified according to Banff 2013 criteria. Histopathologic changes were compared between AT1R positive and negative patients.
  
  
  RESULTS
  75% of patients with positive pre-transplant AT1R Ab had antibody mediated rejection (AMR) compared to 37% of AT1R Ab-negative patients. A trend towards increased interstitial inflammation was observed in the AT1R Ab positive group (p=0.08). More patients in the AT1R Ab positive group had microcirculation inflammation (88% vs 58% with glomerulitis scores ≥1; 75% vs 58% with peritubular capillaritis scores ≥1).
  
  
  CONCLUSIONS
  In kidney transplant recipients with rejection and no DSA, a higher incidence of AMR and worse inflammation scores are observed in the presence of positive pre-transplant AT1R antibodies.
authors.affiliation: Department of Medicine, Renal Electrolyte and Hypertension Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States. Electronic address: Maryann.lim@uphs.upenn.edu.
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Lim
authors.affiliation: Department of Pathology and Laboratory Medicine, Perelman School of Medicine, Philadelphia, PA, United States.
authors.forename: Matthew
authors.initials: M
authors.lastname: Palmer
authors.affiliation: Department of Medicine, Renal Electrolyte and Hypertension Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Department of Pharmacy Services, Hospital of the University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Trofe-Clark
authors.affiliation: Department of Medicine, Renal Electrolyte and Hypertension Division, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
authors.forename: Roy D
authors.initials: RD
authors.lastname: Bloom
authors.affiliation: Department of Medicine, Johns Hopkins University, Baltimore, MD, United States.
authors.forename: Annette
authors.initials: A
authors.lastname: Jackson
authors.affiliation: Department of Medicine, Johns Hopkins University, Baltimore, MD, United States.
authors.forename: Mary Carmelle
authors.initials: MC
authors.lastname: Philogene
authors.affiliation: Clinical Immunology and Histocompatibility Laboratory, Perelman School of Medicine, Philadelphia, PA, United States.
authors.forename: Malek
authors.initials: M
authors.lastname: Kamoun
mesh_terms: D000208:Acute Disease; D000328:Adult; D000920:Antibody-Dependent Cell Cytotoxicity; D001323:Autoantibodies / Q000378:metabolism*; D005260:Female; D005921:Glomerulonephritis / Q000453:epidemiology; D006084:Graft Rejection / Q000453:epidemiology / Q000276:immunology*; D006801:Humans; D015994:Incidence; D007518:Isoantibodies / Q000378:metabolism*; D007668:Kidney / Q000276:immunology / Q000473:pathology*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D044140:Receptor, Angiotensin, Type 1 / Q000276:immunology; D012189:Retrospective Studies; D014657:Vasculitis / Q000453:epidemiology
chemical_list: D001323:Autoantibodies; D007518:Isoantibodies; D044140:Receptor, Angiotensin, Type 1
keywords: Anti-angiotensin II; Antibody; Kidney transplant; Non-HLA; Rejection