牙源性囊肿和成釉细胞瘤体外骨吸收的实验研究

In vitro study on bone resorption of odontogenic cysts and ameloblastomas

目的定量分析牙源性角化囊肿和成釉细胞瘤的体外骨吸收效应,探讨其颌骨吸收机制。方法收集25例牙源性囊肿[牙源性角化囊肿(OKC)14例、牙源性角化囊肿伴感染6例、含牙囊肿(DC)5例]和7例成釉细胞瘤的新鲜组织块行体外培养(24h),取其上清液与SD大鼠(新生5天)颅盖骨培养体系继续培养48h,以原子分光光度计法检测培养体系上清液中的Ca2+含量,从而判断不同牙源性病损在体外导致骨吸收作用的差异。同时采用放射免疫技术检测牙源性病损体外培养上清液中的骨吸收相关因子:白细胞介素6(IL6)、肿瘤坏死因子α(TNFα)、前列腺素E2(PGE2)、骨钙素(BGP)和降钙素(CT)等的含量。结果各组牙源性囊肿和肿瘤引起大鼠颅盖骨培养Ca2+析出的浓度显著高于空白组(P<0.01);OKC伴感染组Ca2+浓度显著高于OKC组和成釉细胞瘤组(P<0.05)。各组牙源性囊肿和成釉细胞瘤培养上清液中IL6、TNFα、PGE2和CT含量显著高于空白对照组(P<0.05);OKC组和OKC伴感染组IL6含量显著高于成釉细胞瘤组(P<0.05);OKC伴感染组CT含量显著高于OKC组和含牙囊肿组(P<0.05)。这些因子和Ca2+含量的相关性分析结果显示,IL6与钙值之间呈显著性正相关(P<0.01)。结论颌骨牙源性病损在体外可促进骨吸收,此作用可能与其产生的某些细胞因子有关。

Objective To investigate the effect of bone resorption by odontogenic cysts and ameloblastomas in vitro. Methods Fragments of odontogenic cysts (14 odontogenic keratocysts, 6 inflamed odontogenic keratocysts, 5 dentigerous cysts) and ameloblastomas (n=7) were incubated in vitro for 24 h. The supernatant was then removed into the culture system of SD rat calvaria. After incubation (48 h), the calcium contents of the media were measured by atom spectrophotometer. The supernatant of odontogenic cysts and ameloblastomas was measured for the bone resorption related factors such as IL-6, TNF-α, PGE_2, bone Gla-containing protein (BGP) and calcitonin (CT) by a radioimmunoassay system. Results The calcium released in the calvaria culture media by all the odontogenic lesions was significantly higher than that in the blank controls (P<0.01). The inflamed odontogenic keratocyst group had a significantly higher calcium concentration than odontogenic keratocyst and ameloblastoma groups (P<0.05). In addition, the concentration of IL-6、TNF-α、PGE_2 and CT in the culture media of all odontogenic lesions were significantly higher than that of the blank controls (P<0.05). IL-6 concentration in the inflamed and non-inflamed odontogenic keratocyst groups were significantly higher than that of ameloblastoma group (P<0.05). CT concentration in the inflamed odontogenic keratocyst was significantly higher than those of odontogenic keratocyst and dentigerous cyst groups (P<0.05). Correlation and regression analysis showed that IL-6 was significantly correlated with the calcium content (P<0.01). Conclusions The odontogenic lesions could promote bone resorption in vitro and it is likely to be related to some of the cytokines secreted by the lesions.