Immunohistochemical identification of MMP-2 and MMP-9 in human dentin: Correlative FEI-SEM/TEM analysis

Annalisa Mazzoni, David H. Pashley, Franklin R. Tay, Pietro Gobbi, Giovanna Orsini, Alessandra Ruggeri, Marcela Carrilho, Leo Tjäderhane, Roberto Di Lenarda, Lorenzo Breschi

Research output: Contribution to journalArticlepeer-review

102 Scopus citations


Matrix metalloproteinases (MMPs) are a family of peptidases trapped within mineralized dentin matrix and involved with degradation of the extracellular matrix components in hybrid layers and caries. Despite their identification through indirect evidences and biochemical assays, MMP-2 and-9 have not been localized within the human dentin extracellular organic matrix. Thus, this study aimed to assess the localization and distribution of MMP-2 and-9 in human dentin organic matrix by employing a correlative field emission in-lens-scanning electron microscopy (FEI-SEM) and transmission electron microscopy (TEM) immuno-histochemical approach. Dentin specimens were submitted either to a preembedding or to a postembedding immuno-labeling technique using primary monoclonal antibodies anti-MMP-2 and anti-MMP-9 and exposed to a secondary antibody conjugated with gold nanoparticles. MMP-2 and-9 labelings were identified in the demineralized dentin matrix as highly electron-dense gold particles dispersed on the collagen fibrils. Correlative FEI-SEM/TEM observations confirmed that MMP-2 and MMP-9 are endogenous components of the human dentin organic matrix and revealed the three-dimensional relationship between these proteinases and the collagen fibrils, showing that both antibodies yielded a similar labeling pattern. In conclusion, the results of the study contribute to reveal distinct distribution pattern of gelatinases and support the hypothesis that these enzymes are intrinsic constituents of the dentin organic matrix after decalcification.

Original languageEnglish (US)
Pages (from-to)697-703
Number of pages7
JournalJournal of Biomedical Materials Research - Part A
Issue number3
StatePublished - Mar 1 2009


  • Dentin
  • High-resolution SEM
  • Immunohystochemistry
  • MMP-2
  • MMP-9
  • Matrix metalloproteinases

ASJC Scopus subject areas

  • Ceramics and Composites
  • Biomaterials
  • Biomedical Engineering
  • Metals and Alloys


Dive into the research topics of 'Immunohistochemical identification of MMP-2 and MMP-9 in human dentin: Correlative FEI-SEM/TEM analysis'. Together they form a unique fingerprint.

Cite this