EVIDENCE OF A DIRECT RELATIONSHIP BETWEEN NEUTROPHIL COLLAGENASE ACTIVITY AND PERIODONTAL TISSUE DESTRUCTION IN-VIVO - ROLE OF ACTIVE ENZYME IN HUMAN PERIODONTITIS

To assess the temporal relationship between periodontal tissue destruc tion and the activity of collagenase, exudate from inflamed periodonta l tissues was collected and latent and active collagenase activities w ere measured by a functional assay in a longitudinal cohort study. Com parisons were made between human subjects with either: 1) inflammation with a previous history of progressive loss of connective tissue and bone support (n=14); 2) inflammation and previous history of bone loss but now clinically stable (n=27); or 3) inflammation and no loss of b one support (n=17). Experiments using specific enzyme inhibitors, bloc king antibodies and SDS-PAGE fluorograph to identify the pattern of co llagen substrate degradation demonstrated that the collagenase activit y was derived from neutrophils and not from bacteria or other host cel ls. Active collagenase activity pooled from 6 sites per subject was re spectively 5 and 6-fold higher in the group with progressive loss of c onnective tissue compared to the groups with either inflamed tissues a lone or with inflammation and previous bone loss. In contrast, latent collagenase was increased up to 2 fold higher in the group with inflam mation but no bone loss compared to the group with progressive lesions . Moreover, the ratio of active to total collagenase activity was 50% higher in the group with progressive lesions. Although in all subjects successive measurements of site-specific active collagenase I month a part demonstrated wide variation (r<0.50), only in sites with progress ive periodontal destruction was there significant increase of active c ollagenase with time (1.28x10(-4) collagenase units per day). There we re also sharp elevations in active enzyme level at the time of detecti on of loss of connective tissue attachment in specific sites of 8 Subj ects. At the time of detection of connective tissue attachment loss, t here was an overall 40% increase of pooled active collagenase activity in all subjects with progressive loss of connective tissue compared t o pre-breakdown sampling times. These data provide strong in vivo evid ence for a direct role of active neutrophil collagenase in the patholo gical destruction of periodontal connective tissue.