肥大细胞转化生长因子β在人慢性根尖周病组织中的表达

目的:本研究旨在观察不同类型慢性根尖周病组织中肥大细胞(mast cells,MCs)的分布,分析转化生长因子β(transforming growth factor-β,TGF-β)在MCs上的表达情况,探讨类胰蛋白酶(tryptase)-TGF-β双阳性MCs在慢性根尖周病免疫病理中的作用。方法:共收集78例样本,分为3组:(1)根尖肉芽肿组25例;(2)根尖囊肿组25例;(3)正常对照组28例。组织标本经4%甲醛固定48 h以上。石蜡包埋、制备组织连续切片。HE染色,观察其组织学改变;采用甲苯胺蓝染色法观察各组标本组织中MCs的数量及MCs脱颗粒情况;采用免疫荧光双染色法,在荧光显微镜下观察各组标本组织中tryptase-TGF-β双阳性MCs的数量。结果:(1)与正常对照组相比,两组慢性根尖周病组织中tryptase-TGF-β双阳性MCs密度显著增多(P0.01);(2)根尖囊肿组tryptase-TGF-β双阳性MCs密度明显高于根尖肉芽肿组(P0.01);(3)与甲苯胺蓝染色法相比,tryptase-TGF-β免疫荧光双染色法结果中各组标本组织的MCs密度显著增多(P0.01)。结论:慢性根尖周病组织,尤其是根尖囊肿组织中tryptaseTGF-β双阳性细胞明显增多,提示tryptase-TGF-β双阳性MCs可能在慢性根尖周病中的致病过程,尤其在根尖周囊肿纤维组织形成中发挥作用。Tryptase免疫荧光染色法比传统鉴别肥大细胞的甲苯胺蓝染色法更灵敏。

Expression of transforming growth factor-β on mast cells in human chronic periapical diseases

AIM: To investigate the distribution of mast cells (MCs) and the expression of transforming growth factor-β (TGF-β) on tryptase positive MCs in different types of human periapical diseases. METHODS: Total 78 cases of specimens were involved in this study, including healthy control, periapical cyst and periapical granuloma. The tissue samples were fixed in 10% formalin for at least 48 h, stained with hematoxylin and eosin for histopathological examination, stained with toluidine blue staining for identifying MCs and MCs degranulation, and stained with double immunofluorescence for identification of tryptase-TGF-β double positive MCs. RESULTS: The density of tryptase-TGF-β double positive MCs in the periapical lesions was significantly higher than that in the healthy controls (P<0.01). The number of TGF-β positive MCs in the periapical cyst was significantly higher than that in the periapical granuloma (P<0.01). Compared with toluidine blue staining, the number of MCs with double immunofluorescence staining significantly increased (P<0.01). CONCLUSION: The TGF-β positive MCs may play an important role in the pathogenesis of human chronic periapical diseases, particularly in the formation of fibrous tissue in periapical cyst. Double immunofluorescence staining is more sensitive than the traditional toluidine blue staining for identifying MCs.