Expression of matrix metalloproteinases and tissue inhibitors of matrix metalloproteinase in the encapsulation process against titanium implant

钛种植体已广泛应用于口腔癌的重建手术和下颌骨骨折的植骨。植入物周围的成纤维组织由活化的成纤维细胞组成，并在整个过程中被重塑。组织重塑是由细胞外基质合成与分解的平衡构成的。成纤维组织中梭形细胞（成纤维细胞或巨噬细胞）、血管内皮细胞和平滑肌细胞中基质金属蛋白酶（MMP）和基质金属蛋白酶组织抑制剂（TIMP）的表达情况如下。MMP-1、MMP-3、MMP-8、MMP-9均为阴性。TIMP-2呈强阳性。相比之下，瘢痕组织内的成纤维细胞既不表达MMPs也不表达TIMPs。此外，我们还研究了钛种植体包封组织周围皮瓣的炎症反应。多数病例可见明显炎性改变。白色念珠菌感染的皮瓣出现炎症变化。真皮浸润的白细胞是表达CD4/CD45RO的记忆型T淋巴细胞。淋巴细胞聚集朗格汉斯细胞（cdla +）。真皮朗格汉斯细胞为B7-2+/CD-83+，与记忆型T淋巴细胞密切接触。CD4+ T淋巴细胞Ki-67标记指数高于CD8+ T淋巴细胞。淋巴管中可见大量成熟朗格汉斯细胞。这些朗格汉斯细胞为B7-2+/B7-1+/CD83+。这些结果表明朗格汉斯细胞在抗钛种植体的包封过程中起重要作用。

Titanium implant has been widely used for the reconstruction surgery of oral cancer and for the osteosynthesis of mandibular fracture.The fibrogenic tissue surrounding the implants consists of activated fibroblasts and is remodeled throughout. Tissue remodeling is made up of the balance between synthesis and decomposition of extracellular matrix. Expression of matrix metalloproteinases (MMP) and tissue inhibitors of matrix metalloproteinase (TIMP) in the spindle-shaped cells (fibroblasts or macrophages), vascular endothelial cells and smooth muscle cells within the fibrogenic tissue was as follows. MMP-1, MMP-3, MMP-8 and MMP-9 were negative. TIMP-2 was strongly positive. By contrast, fibroblasts within the scar tissue expressed neither MMPs nor TIMPs.Furthermore, we investigated the inflammatory response of skin flaps surrounding the encapsulation tissue of titanium implant. Prominent inflammatory changes were observed in most cases. Skin flaps showing inflammatory changes were infected by Candida albicans. Infiltrating leukocytes to the dermis were memory-type T lymphocytes expressing CD4/CD45RO. These lymphocytes were clustered with Langerhans cells (CD la+). Langerhans cells in the dermis were B7-2+/CD-83+, and intimately touched to the memory -type T lymphocytes. Ki-67 labeling index of CD4+ T lymphocytes was higher than that of CD8+ T lymphocytes. Numerous mature Langerhans cells were observed in the lymphatic vessels. These Langerhans cells were B7-2+/B7-1+/CD83+. These results suggest that Langerhans cells play an important roles in the encapsulation process against titanium implant.