Chen S S, Wang K, Zhao J, Wu W C, Wu Y F, Zhao L
State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University, Chengdu, Sichuan, China.
Department of Periodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China.
J Periodontal Res. 2017 Jun;52(3):512-521. doi: 10.1111/jre.12417. Epub 2016 Sep 14.
Periodontitis is an infectious disease in which the host immune and inflammatory responses play essential roles in resistance to bacterial infection, as well as the induction of tissue destruction if the immune response is dysregulated. The triggering receptor expressed on myeloid cells (TREMs) modulates inflammatory and innate immune signaling. TREM-1 is considered as an amplifier of the immune response, while TREM-2 is a negative regulator that has yet to be explored in periodontal disease before. We hypothesized that TREMs participated in the innate immune responses during the pathogenesis of periodontitis. Therefore, the aim of this study was to evaluate TREM-1 and TREM-2 expression in the gingival tissues from patients with chronic periodontitis and healthy subjects as well as their correlation with clinical periodontal parameters. This study is the first to identify TREM-2 in periodontal tissue, as well as the protein expression changes of TREM-1 and TREM-2 in periodontal tissues.
Gingival tissue sections were collected from 31 healthy subjects and 53 patients with chronic periodontitis. Immunohistochemistry and quantitative real-time polymerase chain reaction were employed to evaluate the protein and mRNA expression of these receptors in gingival tissues. The recorded clinical parameters were probing depth, clinical attachment loss, plaque index and bleeding on probing.
In addition to myeloid cells in gingival connective tissues, TREM-1 and TREM-2 were also found expressed in gingival epithelial cells. In particular, TREM-1 was detected in almost all gingival epithelium from both healthy and inflamed biopsies. The expression levels of TREM-1 and TREM-2 were significantly increased in the periodontitis group compared to the healthy group. Increased levels of these receptors are to be positively correlated with site-specific periodontal parameters.
The increased expression of TREM-1 and TREM-2 levels in periodontitis may confer diagnostic and potential therapeutic targets as well as indicating their association with the clinical severity of the disease.
牙周炎是一种感染性疾病，宿主免疫和炎症反应在抵抗细菌感染中起重要作用，但若免疫反应失调则会引发组织破坏。髓系细胞触发受体（TREMs）可调节炎症和固有免疫信号传导。TREM-1被认为是免疫反应的放大器，而TREM-2作为负调节因子，此前在牙周疾病中尚未得到研究。我们推测TREMs参与了牙周炎发病过程中的固有免疫反应。因此，本研究旨在评估慢性牙周炎患者和健康受试者牙龈组织中TREM-1和TREM-2的表达情况，以及它们与临床牙周参数的相关性。本研究首次在牙周组织中鉴定出TREM-2，以及牙周组织中TREM-1和TREM-2的蛋白表达变化。
收集31名健康受试者和53名慢性牙周炎患者的牙龈组织切片。采用免疫组织化学和定量实时聚合酶链反应评估这些受体在牙龈组织中的蛋白和mRNA表达。记录的临床参数包括探诊深度、临床附着丧失、菌斑指数和探诊出血。
除牙龈结缔组织中的髓系细胞外，还发现TREM-1和TREM-2在牙龈上皮细胞中表达。特别是，在健康和炎症活检的几乎所有牙龈上皮中均检测到TREM-1。与健康组相比，牙周炎组中TREM-1和TREM-2的表达水平显著升高。这些受体水平的升高与特定部位的牙周参数呈正相关。
牙周炎中TREM-1和TREM-2水平的升高可能为诊断和潜在治疗靶点提供依据，并表明它们与疾病临床严重程度的关联。
