D. Prigent et al., PROTEOGLYCAN DEGRADING ACTIVITY IN GRANULOMATOUS INFLAMMATION - COMPARISON BETWEEN THE C57BL 6 AND C57BG/BG MOUSE/, Inflammation research, 45(10), 1996, pp. 494-498
Objective and Design: Proteoglycan (GAG) and collagen are lost from ca
rtilage juxtaposed to murine granulomatous tissue in both control and
C57bg/bg (elastase deficient mice). The objective was to extract and c
haracterise proteoglycan degrading activity within granulomas of both
strains. Materials: 15 animals (female C57b1/6 and C57bg/bg mice) per
group were used. Treatment: Cotton-wrapped rat femoral head cartilages
were implanted subcutaneously into the dorsum of the mice and the gra
nulomas excised fourteen days later. Methods: Granuloma and granuloma
cell-granule preparations were fractionated within a detergent-based b
uffer and tested for their abilities to degrade cartilage in vitro in
the presence and absence of enzyme inhibitors. Elastase and cathepsin
G activities were also assessed using specific substrates. Statistical
significance was calculated using Student's t-test. Results: Extracts
from both strains induced the loss of cartilage GAG. This was correla
ted with cathepsin G activity (r=0.96) and was inhibited by a specific
cathepsin-G inhibitor (95%, p < 0.001), but not specific elastase or
metalloproteinase inhibitors. Elastase activity but not that of cathep
sin G was absent in the beige mice, whilst both enzymes were active in
the controls. Conclusions: It appears that neutrophil cathepsin G may
play an important role in the degradation of cartilage proteoglycan i
n the murine cotton-pellet granuloma in both C57b1/6 and C57bg/bg.