FIG. 1.

Absence of MMP-1 activity in GCF samples. APMA-activated MMP-8 from neutrophil preparations, MMP-1 from cultured fibroblasts, and GCF samples from eight different periodontitis patients were incubated with blocking antibody to MMP-1 (+) or distilled water (−) for 1 h and then tested by SBA. Digestion patterns are shown above. Note that, in the MMP-1 sample, activity was completely inhibited by the neutralizing antibody while the activity in neutrophils (MMP-8) and in GCF samples remained unchanged.