Expression of Metalloproteinase 2 in the Cell Response to Porous Demineralized Bovine Bone Matrix

Abstract

The purpose of the study was to analyze the involvement of metalloproteinase 2 (MMP-2) and macrophages in the tissue and cell response to the organic graft material produced from bovine cancellous bone. Thirty adult male white Wistar rats (Rattus norvegicus) received implants of blocks of demineralized bovine bone matrix between the fasciae of the quadriceps muscle. The specimens collected at 3, 7, 14, 21 and 28 days after implantation (n = 6/period). Sections of 6 microm thick were stained with hematoxylin and eosin and immunolabeled with anti-MMP-2 and anti-CD68 using standard avidin-biotin-peroxidase method. The tissue response to the material was initially mediated by polymorphonuclear neutrophils, evolving to a mononuclear inflammatory infiltrate with macrophages and few lymphocytes and plasma cells and presence of inflammatory multinucleated giant cells (GC) in contact with the material that exhibited signs of resorption. The number of cells immunolabeled to MMP-2 was highest at day 7 (103.2 +/- 39.1), but significantly decreased (F = 3.67; p = 0.044) until day 28 (45.9 +/- 13.1). CD68 immunostaining also significantly decreased (F = 6.75; p = 0.007) from day 7 (49.5 +/- 10.4) to day 28 (19.5 +/- 8.9). A positive and statistically significant correlation was observed between the evolutions of these two variables. The material had been almost completely resorbed at day 28. Among cells present at the granuloma, anti-MMP-2 immunostaining was predominant and more intense in macrophages, yet lightly immunolabeled multinucleated giant cells were found in close contact with the material. Thus, considering the experimental limitations of this study, we concluded that MMP-2 produced by macrophages participates in the resorption of demineralized bovine bone.

Development of secondary palate requires strict regulation of ECM remodeling: sequential distribution of RECK, MMP-2, MMP-3, and MMP-9

“…The slides were dried overnight at 37°C, the paraffin was removed in xylene, and re-hydration was achieved with consecutive ethanol washes (100%, 95%, 70%). Endogenous peroxidase was blocked in 3% hydrogen peroxide for 45 min, antigenic retrieval was performed in phosphate-citrate buffer (pH 6.0 at 96°C; P4809, Sigma-Aldrich, Mo., USA) for 20 min, and non-specific binding was blocked by incubation with 4% non-fat milk solution for 20 min, as described elsewhere (Accorsi-Mendonça et al 2005;Menezes et al 2006;Corotti et al 2009;Zambuzzi et al 2009b). Sections were incubated overnight at 4°C with polyclonal primary antibodies, namely goat anti-human MMP-2 (sc 6838), goat anti-human MMP-3 (sc 6839), goat anti-mouse MMP-9 (sc 6841), and goat anti-mouse RECK (sc 9689).…”

Intracellular signal transduction as a factor in the development of “Smart” biomaterials for bone tissue engineering

“…For this purpose, biomaterials for bone repair are constantly being developed and modified with the ideal intent of stimulating the chemo-recruitment, proliferation, and differentiation of osteoprogenitor cells on a given injured region (Accorsi-Mendonça et al, 2005;Zambuzzi et al, 2005;Zambuzzi et al, 2006;Zambuzzi et al, 2009a). If the biomaterial does not induce the biomolecular cascade of reaction that induce/accelerate regeneration, it should at least serve as a scaffold for the migration and proliferation of host cells.…”

Morphologic evaluation and expression of matrix metalloproteinases-2 and 9 and nitric oxide during experimental periodontal disease in rat

“…According to Accorsi-Mendonça et al 2005, MMP-2 also plays a role in the resorption of the extracellular matrix and degradation of the demineralized organic bovine bone, essentially constituted by type I collagen, especially when expressed in macrophages and multinucleated cells. Additionally, MMP-9 is specifically expressed in the osteoclastic lineages of bone cells, and degrades collagens and related proteins in bone matrix (Reponen et al 1994).…”