Collagenolysis is a prominent feature in acute and chronic inflammation. The loss of collagen, either quantitatively or qualitatively, may lead to abnormal function of various tissues. Collagenases, metalloproteinases primarily responsible for the degradation of native collagen, are synthesized by a variety of cell types. While the interstitial collagenases of the fibroblast and synovial cell apppear virtually identical, the collagenase of the neutrophil shows distinct, although controversial, differences in synthesis and storage as well as biochemical and immunological differences. This project will utilize a monoclonal antibody to neutrophil collagenase developed and characterized by the investigator to aid in the purification of this enzyme from neutrophil supernatants (see appended reprint and manuscript). The purified enzyme will be characterized by quantitative amino acid analysis, amino-terminal amino acid sequence analysis, peptide mapping and neutral sugar analysis. The substrate specificity of the purified collagenase will be assessed as well as the activation energy and deuterium isotope effect. The specific cleavage site of the degraded collagen will be determined by amino acid sequence analysis. The degree of immunological cross-reactivity between human neutrophil and skin collagenase will be evaluated in a competitive inhibition ELISA using a polyclonal antibody to HNC. The proposed studies will provide an increased understanding of the biochemistry of neutrophil collagenase from both structural and functional aspects as well as further define the differences between this collagenase and the previously characterized collagenases. This fundamental biochemical and immunologic characterization should provide a better assessment of the potential of neutrophil collagenase as well as facilitate further studies on the actual participation of this proteinase in connective tissue destruction during inflammation.
