Department of Operative Dentistry, University of North Carolina, Chapel Hill, NC 27599, USA.
Caries Res. 2011;45(5):453-9. doi: 10.1159/000330601. Epub 2011 Aug 26.
It has been suggested that host matrix metalloproteinase-2 (MMP-2) present in dentin may be involved in caries progression, however, its response to caries is not known. Bone sialoprotein (BSP) has been implicated in dentin mineralization and MMP-2 modulation.
To identify and compare the distribution of MMP-2 and BSP in healthy human coronal dentin and those with early caries.
Freshly extracted 3rd molars and premolars with and without early caries were fixed, demineralized and subjected to immunohistochemistry using a monoclonal anti-MMP-2 antibody and monoclonal anti-BSP antibody with an avidin-biotin complex method. Immunoreactivity was visualized with 3,3'-diaminobenzidine substrate and observed under light microscopy.
Immunohistochemical analysis revealed that MMP-2 and BSP are not detected in the tubule lumens of healthy dentin. However, intense immunoreactivity for MMP-2 and BSP was detected in association with the full length of the caries-affected dentinal tubules. The MMP-2 and BSP at the dentino-enamel junction appeared unaltered.
The results indicate that MMP-2 and BSP may be actively secreted by odontoblasts in response to carious insult. MMP-2 and BSP accumulation in the caries-affected dentinal tubules may indicate their potential involvement in the host defense mechanism which results in calcification of regions affected by the carious process.
有研究表明，牙本质中存在的宿主基质金属蛋白酶-2（MMP-2）可能与龋病进展有关，但目前尚不清楚其对龋病的反应。骨涎蛋白（BSP）已被认为与牙本质矿化和 MMP-2 调节有关。
确定并比较 MMP-2 和 BSP 在健康人冠部牙本质和早期龋牙本质中的分布。
用抗 MMP-2 单克隆抗体和抗 BSP 单克隆抗体，通过免疫组织化学方法，对无龋和有早期龋的第三磨牙和前磨牙进行检测。采用 avidin-biotin 复合物法，用 3,3'-二氨基联苯胺底物进行免疫反应显色，在光镜下观察。
免疫组织化学分析显示 MMP-2 和 BSP 均未在健康牙本质的管腔中检测到。然而，在受龋影响的牙本质小管全长均可见到强烈的 MMP-2 和 BSP 免疫反应。牙釉质牙本质交界处的 MMP-2 和 BSP 似乎没有改变。
结果表明 MMP-2 和 BSP 可能是成牙本质细胞对龋损刺激的主动分泌。MMP-2 和 BSP 在龋病受累牙本质小管中的积聚可能表明它们可能参与宿主防御机制，导致受龋病过程影响的区域发生钙化。
