Recombinant human proteinase 3, the Wegener's autoantigen, expressed in HMC-1 cells is enzymatically active and recognized by c-ANCA

Ulrich Specks, David N. Fass, Michael P Fautsch, Amber M. Hummel, Margaret A. Viss

Research output: Contribution to journalArticle

41 Scopus citations


We developed a stable expression system for conformationally intact recombinant human PR3 (rPR3) using the human mast cell line HMC-1. Like in U937 cells, the rPR3 is processed from a 34 kDa precursor to the 29 kDa mature form, primarily as the result of oligosaccharide trimming. The rPR3 binds [3H]DFP and hydrolyzes the substrate N-methoxysuccinyl-Ala-Ala-Pro-Val-pNA. The enzymatic activity is inhibited by greater than 95% by α1-PI. The rPR3 and the enzymatically inactive mutant rPR3-S176A are both packaged in granules. Thus, proteolytic autoprocessing is not required for PR3's targeting to granules. This rPR3 is the first to be recognized by most c-ANCA from WG patients and all anti-PR3 ANCA that were detected by standard anti-PR3 specific ELISA. This expression system for rPR3 represents a versatile tool for the analysis of its intracellular processing, structure-function relationships and interaction with autoantibodies.

Original languageEnglish (US)
Pages (from-to)265-270
Number of pages6
JournalFEBS Letters
Issue number3
StatePublished - Jul 29 1996



  • Anti-neutrophil cytoplasmic antibody
  • Expression system
  • Human
  • Mast cell
  • Neutral serine protease
  • Proteinase 3

ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

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