Conclusion
This study demonstrated that IL-21 is potentially involved in the pathogenesis of apical periodontitis lesions. A role in the exacerbation of chronic inflammation, as well as in bone resorption, is suspected. Further studies are required to elucidate the specific functions of IL-21 in periradicular inflammatory processes. 目的: 检测白细胞介素-21（IL-21）和破骨细胞核因子κB受体活化因子配体（RANKL）在根尖囊肿和根尖肉芽肿中的表达，分析两者在根尖周病中的关系，探讨IL-21在根尖周炎发病机制中的作用。 方法: 收集根尖囊肿23例和根尖肉芽肿32例作为实验组，记录相关病例的病损大小及有无叩痛表现；10例健康牙龈组织为对照组。利用免疫组织化学法检测所有样本中IL-21和RANKL蛋白的表达水平，分析IL-21的表达水平与RANKL表达、根尖病灶大小及叩痛的相关性。 结果: 所有病变组织均可检测到IL-21阳性细胞，而健康牙龈组织则未检测到IL-21的表达。根尖囊肿和肉芽肿中IL-21的表达强度分别为59.92±6.57和36.80±6.81，RANKL的表达强度分别为68.81±18.59和36.12±14.87。根尖囊肿组两种蛋白的表达水平均高于肉芽肿组（P<0.05）。相关性分析表明，IL-21的表达水平与RANKL及根尖病灶大小均呈正相关关系（P<0.05）。 结论: IL-21存在于人慢性根尖周炎病损组织中，其表达水平与RANKL的表达量及病损大小呈正相关关系；IL-21可能通过促进RANKL蛋白的表达参与慢性根尖周炎的发病机制。
Methods
A total of 32 PGs and 23 RCs were selected as experimental samples. Lesion size and occurrence of tenderness were recorded. Up to 10 healthy gingival tissues were collected as normal control samples. All tissues were subjected to immunohistocheincal analysis with anti-human IL-21 and RANKL polyclonal antibodies. The correlations of IL-21 with RANKL, lesion size, and the occurrence of tenderness of the PGs and RCs were evaluated.
Objective
This study aimed to detect the immunoexpression of interleukin-21 (IL-21) and receptor activator. of nuclear factor KB ligand (RANKL) in periapical granulomas (PGs) and radicular cysts (RCs). The interaction of IL-21 with RANKL and its role in periapical pathogenesis were also speculated.
Results
IL-21-positive cells were detected in all periapical lesion tissues but not in normal tissues. In the cyst group and granuloma group, the corresponding expression levels of IL-21 were 59.92±6.57 and 36.80± 6.81, whereas those of RANKL were 68.81±18.59 and 36.12±14.87, respectively. Moreover, t-test revealed a significantly higher expression of IL-21 and RANKL in RCs than in PGs (P<0.05). IL-21 and RANKL were positively correlated in both PGs and RCs (P<0.05). Furthermore, IL-21 was correlated with lesion size (P<0.05).