Increases in mast cells and chymase in fibroproliferative paws of collagen-induced arthritic mice

Inflamm Res. 1999 Jun;48(6):318-24. doi: 10.1007/s000110050467.


Objective and design: To investigate whether mast cells (MCs) and chymase, the major protease of murine MCs, were involved in a chronic fibroproliferative disorder of the paws associated with type II collagen (CII)-induced arthritis.

Materials: Eighteen DBA/1J mice were divided into 3 groups and were used to study fibroproliferative changes in paws elicited by immunization.

Treatment: Arthritis was induced by immunization with CII, which was intradermally injected as an emulsion made with adjuvant. A booster shot was done 3 weeks after the initial shot. A group with no treatment and that received adjuvant alone served as control.

Methods: Twelve weeks after the booster shot, inflammation of the paws was evaluated for pathological and biochemical indices. Chymase activity was determined with a chromogenic peptide substrate.

Results: In CII-immunized group, collagen bundles accumulated around the destructed joints. In accordance with the pathological findings, MC density in the affected paws was increased (154.8+/-13.3/mm2; p<0.05 vs. control) and chymase activity was also increased (29.5+/-2.8 mU/mg protein; p<0.01 vs. control).

Conclusions: The present results demonstrate increases in MCs and chymase in fibroproliferative paws of collagen-induced arthritic mice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Arthritis, Rheumatoid / chemically induced
  • Arthritis, Rheumatoid / enzymology*
  • Arthritis, Rheumatoid / pathology*
  • Cell Count
  • Chymases
  • Collagen
  • Fibrosis
  • Mast Cells / pathology*
  • Mice
  • Mice, Inbred DBA
  • Serine Endopeptidases / metabolism*
  • Statistics, Nonparametric


  • Collagen
  • Serine Endopeptidases
  • Chymases