In situ detection of matrix metalloproteinase-9 (MMP-9) in gingival epithelium in human periodontal disease.
OBJECTIVE
As the periodontal lesion develops, the junctional epithelium migrates apically in conjunction with the dissolution of the most coronal Sharpey's fibers. Because matrix metalloproteinase-9 (MMP-9) has been identified in migrating epithelial cells and invading tumors, we propose that this enzyme is produced by gingival keratinocytes in advanced periodontal lesions.


METHODS
To test this idea, biopsies of inflamed gingival tissues were obtained from patients with advanced periodontitis. Healthy gingival tissue samples were utilized as controls. The presence and activity of MMP-9 was evaluated by combining indirect immunofluorescence of gingival tissue samples and gelatin zymography of gingival epithelium separated from connective tissue.


CONCLUSIONS
The staining pattern showed the presence of MMP-9 in junctional and pocket gingival epithelial cells, polymorphonuclear neutrophils (PMNs) and as a scattered deposit along connective tissues of periodontitis-affected gingival tissues. Gelatin zymography permitted the identification of pro-MMP-9 in surcular/pocket epithelium derived from inflamed gingival tissues. Lower levels of MMP-9 were detected in epithelium not exposed to inflammation. These observations suggest a role for MMP-9 in gingival epithelial response to periodontal infection.
Faculty of Odontology, University of Chile, Santiago, Chile. psmithf@inta.cl
Patricio C
PC
Smith
Valeria C
VC
Muñoz
Lucía
L
Collados
Alejandro D
AD
Oyarzún
D000328:Adult; D000368:Aged; D003238:Connective Tissue / Q000201:enzymology; D004591:Electrophoresis, Polyacrylamide Gel; D004846:Epithelial Attachment / Q000201:enzymology; D004847:Epithelial Cells / Q000201:enzymology; D004848:Epithelium / Q000201:enzymology; D019084:Fluorescent Antibody Technique, Indirect; D005881:Gingiva / Q000201:enzymology*; D005888:Gingival Pocket / Q000201:enzymology; D006801:Humans; D015603:Keratinocytes / Q000201:enzymology; D020780:Matrix Metalloproteinase 9 / Q000032:analysis*; D008875:Middle Aged; D009504:Neutrophils / Q000201:enzymology; D010514:Periodontal Pocket / Q000201:enzymology; D010518:Periodontitis / Q000201:enzymology*
D020780:Matrix Metalloproteinase 9