文档介绍：结果:
1、组织学观察
正常对照组牙周膜组织结构正常,未见炎症细胞浸润。根尖周肉芽组:可见明显的炎性细胞浸润。根尖囊肿组:上皮层表现为细胞间水肿、以及上皮层下方明显的慢性炎症细胞浸润;囊壁的纤维组织层见密集的胶原纤维组织。
2、TGF-β1 免疫组织化学法结果
正常对照组未见 TGF-β1 的表达。根尖肉芽肿组:TGF-β1 在毛细血管内皮细胞和少量的炎症细胞上表达。根尖囊肿组:TGF-β1 在囊肿壁的上皮层细胞、上皮层下方的炎症细胞和毛细血管中大量表达;在囊肿的纤维组织层,TGF-β1 在成纤维细胞、纤维组织、血管和血管周围浸润的炎症细胞上均有大量的表达。结果显示, TGF-β1 在根尖囊肿表达明显高于根尖肉芽肿(P<)。
3、α-SMA 免疫组织化学法结果
正常对照组α-SMA 表达阴性。根尖肉芽肿组:α-SMA 主要表达于毛细血管内皮细胞及毛细血管壁。根尖囊肿组:在根尖囊肿的上皮层细胞轻度表达α-SMA,毛细血管壁和毛细血管的内皮细胞均表达α-SMA;在根尖囊肿的纤维组织层见
α-SMA 大量表达。结果显示,根尖囊肿组α-SMA 的表达明显高于根尖肉芽肿组(P
<)。结论:
1. 与正常组相比较,各组慢性根尖周疾病组织中 TGF-β1 和α-SMA 的表达水平明显升高。
2. 与根尖肉芽肿组相比较,根尖囊肿组 TGF-β1 和α-SMA 的表达水平明显升高。
TGF-β1 可能在慢性根尖周疾病的致病机制,尤其在根尖周囊肿的纤维组织形成中发挥作用,其具体的作用机制仍需要进一步的研究。
关键词:
根尖周疾病;转化生长因子-β1;α-平滑肌肌动蛋白
Abstract
Background and objective
Periapical lesions are a response of the host, which actively prevents dissemination of bacteria from an infected root canal into the surrounding tissue. Although it has been well recognized that the immune response participates in the formation of periapical lesions, their pathogenicity has not been clearly defined.
Transforming growth factor-β1 (TGF-β1) is one of the cytokines released during tissue injury and by inflammatory cells exposed to bacteria and their products. It has proinflammatory properties, triggering the production of bone-resorptive cytokines. In a variety of fibrotic diseases and wound healing studies, it has been shown that the differentiation of myofibroblast induced by TGF-β1 is the key to tissue repair, can accelerate the injury healing and tissue reconstruction.
α-smooth muscle actin (α-SMA), as the most used marker of myofibroblast, has been studied in wound healing and fibrotic diseases. It is widely accepted that after tissue injury, fibroblasts expressing α-SMA stimulated by TGF-β1, causing excessive extracellular matrix synthesis and accumulation, lead to fibrous lesions ans and tissue.
Whether the expression of TGF-β1 and α-SMA takes part in the pathogenesis of periapical diseases has not been reported.