Significant correlation between matrix metalloproteinase activity and tumor necrosis factor-α in salivary extravasation mucoceles

We examined the matrix metalloproteinase (MMP) activity and tumor necrosis factor (TNF)-α in luminal fluid of 18 extravasation mucoceles and in saliva from Wharton's duct of five patients by means of gelatin zymography and enzyme immunoassay, respectively. The luminal fluid showed a high level of MMP activity compared with the saliva. Quantitative determination by enzyme immunoassay revealed that the luminal fluid contained higher levels of TNF-α than the saliva. In addition, the amount of TNF-α in luminal fluid exhibited a direct correlation with MMP activity estimated by densitometric analysis of gelatin zymograms. Since TNF-α stimulates the production of MMPs from cells such as fibroblasts, these results suggest that TNF-α is one of the causal molecules that enhance the accumulation of proteolytic enzymes in luminal fluid of mucoceles.