A study on possible roles of granulocyte neutral proteinases and the control mechanism of their activities in the process of periodontal breakdown

为了阐明宿主来源的溶酶体蛋白在牙周破裂机制中的作用，我们研究了组织蛋白酶G和髓质蛋白这两种主要的丝氨酸蛋白酶。在牙周炎患者的龈沟液中，几乎没有检测到这两种酶的全部活性，而酶联免疫吸附试验检测到的这两种酶的量随着牙周炎患者牙周炎的量的增加而增加，这表明这两种酶参与了牙周炎的进展。它们在GCF中失去活性的原因是它们被其特异性的血清衍生蛋白酶抑制剂，特别是α_1-蛋白酶抑制剂所阻断，因为用每种酶和α_1-蛋白酶抑制剂对GCF进行的免疫印迹分析显示，它们各自的酶和抑制剂的蛋白条带很弱，而它们的复合体有一条很强的条带。不采取所有口腔卫生措施21d…所致牙周炎的实验研究此外，在各种临床监测指标检测到炎症之前，GCF中这些酶的显著升高，提示参与了炎症的发展。在炎症的牙龈组织中，这些酶仅局限于中性粒细胞和巨噬细胞，尤其集中在袋上皮附近，部分伴有细胞外脱颗粒。这一发现表明，除了对细菌病原体的宿主防御机制外，这些酶还参与了宿主组织的直接降解。此外，将纯化的酶注射到兔牙龈中可引起炎症反应，其特征是血管损伤明显，炎症细胞包括中性粒细胞和巨噬细胞轻度渗入。然而，这些酶的功能在它们的特异性抑制剂、α_1-蛋白水解酶抑制剂或α_1-抗糜蛋白酶的处理下完全丧失。根据这项研究的发现，组织蛋白酶G和延髓蛋白存在于牙周组织和牙龈组织中，并参与了血清衍生的蛋白酶抑制物调节的宿主防御机制。一旦酶-抑制物失去平衡，这两种酶反过来对牙周组织起破坏性作用。较少

To clarify the role of host-derived lysosomal proteinases in the mechanism of periodontal breakdown, cathepsin G and medullasin, two major serine proteinases, were investigated. In gingival crevicular fluid (GCF) obtained from periodontitis patients, almost all activities of both enzymes were not detected, while the amounts of both enzymes determined by enzyme-linked immunosorbent assay increased with increasing GCF volume, indicating the participation of the enzymes in the progression of periodontitis. The reason why their activities were lost in GCF is suggested that they were blocked by their specific serum-derived proteinase inhibitor, especially alpha_1-proteinase inhibitor, since immunoblotting analyzes of GCF using each enzyme and alpha_1-proteinase inhibitor revealed a weak protein band of the respective enzyme and the inhibitor alone and a strong band of the complex of those. In experimental gingivitis of volunteers induced by refraining from all oral hygiene measures for 21 d … More ays, a remarkable increase of these enzymes in GCF were shown prior to the detection of inflammation monitored by various clinical parameters, suggesting the involvement in the development of inflammation. In inflamed gingival tissues, these enzymes were restricted in neutrophils and macrophages and concentrated especially in the vicinity of pocket epithelium partly with degranulation extracelluarly. This finding suggests the participation of these enzymes in direct degradation of host tissues besides the host-defensive mechanism against bacterial pathogens. Moreover, purified enzymes injected into rabbit gingivae caused inflammatory response characterized by noticeable injury to vessels and mild infiltration of inflammatory cells including neutrophils and macrophages. The function of the enzymes, however, were completely lost with the treatment by their specific inhibitor, alpha_1-proteinase inhibitor or alpha_1-antichymotrypsin. From the findings in this study, cathepsin G and medullasin are present in GCF and gingival tissue and participated in the host-defensive mechanism modulated by serum-derived proteinase inhibitors. Once the enzyme-inhibitor balance is lost, these two enzymes conversely play a destructive role against periodontal tissues. Less