"Atypical p-ANCA" in IBD and hepatobiliary disorders react with a 50-kilodalton nuclear envelope protein of neutrophils and myeloid cell lines

Gastroenterology. 2000 Aug;119(2):310-22. doi: 10.1053/gast.2000.9366.


Background & aims: Atypical "antineutrophil cytoplasmic antibodies" (ANCA) are present in patients with ulcerative colitis (UC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH). Recently, we showed that atypical p-ANCA react with nuclear envelope proteins of neutrophils. Based on this observation, we aimed to characterize the nuclear antigen recognized by atypical p-ANCA.

Methods: We prepared cytoplasmic and nuclear extracts of human neutrophils, human HL-60, and murine 32D myeloid cells. Proteins were resolved by 1- and 2-dimensional gel electrophoresis. Reactive proteins were detected by immunoblotting with sera from 118 individuals (UC, 25; PSC, 28; AIH, 35; disease and normal controls, 30). Atypical p-ANCA (n = 64) were affinity-purified against the reactive protein and investigated for their immunofluorescence pattern using confocal microscopy.

Results: Immunoblotting showed reactivity to a myeloid-specific 50-kilodalton nuclear protein with an isoelectric point of pH 6.0 detected in 92% (59 of 64) of the patients with inflammatory bowel or hepatobiliary diseases and atypical p-ANCA. Affinity-purified antibodies against the 50-kilodalton protein gave a nuclear rim-like fluorescence on myeloid cells examined by immunofluorescence microscopy. Affinity-purified antibodies did not recognize antigens in nonmyeloid cells.

Conclusions: Atypical p-ANCA in UC, PSC, or AIH recognize a 50-kilodalton myeloid-specific nuclear envelope protein.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Animals
  • Antibodies, Antineutrophil Cytoplasmic / immunology*
  • Antibody Specificity
  • COS Cells
  • Cell Fractionation
  • Child
  • Cholangitis, Sclerosing / immunology*
  • Colitis, Ulcerative / immunology*
  • Female
  • Fluorescent Antibody Technique
  • HL-60 Cells
  • HeLa Cells
  • Hepatitis, Autoimmune / immunology*
  • Humans
  • Immune Sera
  • Liver / cytology
  • Male
  • Middle Aged
  • Molecular Weight
  • Neutrophils / chemistry
  • Neutrophils / immunology*
  • Nuclear Envelope / chemistry
  • Nuclear Envelope / immunology*
  • Nuclear Proteins / analysis
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / immunology


  • Antibodies, Antineutrophil Cytoplasmic
  • Immune Sera
  • Nuclear Proteins