title: Pathologic findings in lung allografts with anti-HLA antibodies.
abstract: BACKGROUND
  Despite data indicating a positive correlation between donor-specific anti-HLA antibodies (DSAs) and early development of bronchiolitis obliterans syndrome (BOS) in lung allografts, the role of an antibody-mediated process in acute and chronic lung allograft rejection has not been elucidated. In this study we evaluated pathologic features of transplant lung biopsies in patients with and without DSAs.
  
  
  METHODS
  Forty-one lung transplant biopsies from 41 patients at our institution were included in our study. The biopsy H&E slides were reviewed in a blinded fashion, and scored for presence of microvascular inflammation, acute rejection, bronchiolar inflammation and acute lung injury, as well as diffuse alveolar damage (DAD). Microvascular inflammation was graded by the presence of capillary neutrophils on a scale of 0 to 4(+). For immunohistochemical analysis, the pattern and intensity of staining for C4d and C3d deposition were evaluated in airways and alveolar capillaries.
  
  
  RESULTS
  Histopathology suspicious for antibody-mediated rejection (AMR)-defined as≥2(+) neutrophilic infiltration and/or DAD-were more common in DSA-positive cases than controls (11 of 16 vs 6 of 25, p<0.01). Evidence of allograft dysfunction was significantly more common among patients with both DSA and suspicious histopathology compared with controls (5 of 10 vs 3 of 25, p = 0.03). The combination of DSAs and histopathology suspicious for AMR was associated with both BOS (p = 0.002) and mortality (p = 0.03). Immunohistochemistry for C3d and C4d showed no correlation with each other, DSAs or histopathology.
  
  
  CONCLUSIONS
  Grade 2(+) neutrophilic infiltration is the histopathologic finding most closely related to DSAs with graft dysfunction and development of BOS in lung transplant recipients and may be a marker for AMR.
authors: Division of Anatomic Pathology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90025, USA.
authors: Matthew M
authors: MM
authors: DeNicola
authors: Sam S
authors: SS
authors: Weigt
authors: John A
authors: JA
authors: Belperio
authors: Elaine F
authors: EF
authors: Reed
authors: David J
authors: DJ
authors: Ross
authors: W Dean
authors: WD
authors: Wallace
mesh_terms: D000328:Adult; D000368:Aged; D000906:Antibodies / Q000276:immunology*; D001706:Biopsy; D001989:Bronchiolitis Obliterans / Q000209:etiology; D005260:Female; D006085:Graft Survival; D006680:HLA Antigens / Q000276:immunology*; D006801:Humans; D016040:Lung Transplantation / Q000009:adverse effects / Q000276:immunology* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014019:Tissue Donors; D014184:Transplantation, Homologous; D055815:Young Adult
chemical_list: D000906:Antibodies; D006680:HLA Antigens