Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou 510055, Guangdong, China.
Hospital of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou 510055, Guangdong, China.
Arch Oral Biol. 2020 Sep;117:104794. doi: 10.1016/j.archoralbio.2020.104794. Epub 2020 Jun 8.
This study aims to investigate the expression pattern of nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 6 (NLRP6) in human dental pulp tissues and cells, and roughly explore the role of NLRP6 in dental pulp immunity.
Immunohistochemistry and immunofluorescence double staining were performed to determine the expression and localization of NLRP6 in healthy and inflamed pulp tissues. The expression of NLRP6 in human dental pulp cells (HDPCs) was investigated by immunocytofluorescence. Furthermore, reverse transcription polymerase chain reaction (RT-PCR) and western blot were used to evaluate the impact of lipopolysaccharide (LPS) stimulation on NLRP6 expression in HDPCs. Last, NLRP6 gene was silenced by lentiviral short hairpin RNA to explore the impact of NLRP6 on LPS-induced interleukin (IL)-1β.
NLRP6 was predominantly expressed in odontoblasts layer and blood vessels of healthy dental pulp, as well as infiltrated immune cells and fibroblasts of inflamed pulp. Further immunofluorescence double staining showed that pericytes and endothelial cells in the dental pulp blood vessels, macrophages and T cells as well as fibroblasts in the inflamed pulp expressed NLRP6. NLRP6 was also basically expressed in cultured HDPCs and upregulated by LPS stimulation. Knockdown of NLRP6 in HDPCs significantly inhibited the LPS-induced IL-1β expression.
Our study revealed the expression and distribution of NLRP6 in human dental pulp tissues. Furthermore, NLRP6 was also basically expressed in cultured HDPCs, which could be upregulated by LPS stimulation, indicating the involvement of NLRP6 in dental pulp immune response.
本研究旨在探讨核苷酸结合寡聚化结构域样受体家族富含吡咯结构域蛋白 6（NLRP6）在人牙髓组织和细胞中的表达模式，并初步探讨 NLRP6 在牙髓免疫中的作用。
采用免疫组织化学和免疫荧光双染法检测 NLRP6 在健康和炎症牙髓组织中的表达和定位。采用免疫细胞荧光法检测 NLRP6 在人牙髓细胞（HDPCs）中的表达。此外，采用逆转录聚合酶链反应（RT-PCR）和蛋白质印迹法评估脂多糖（LPS）刺激对 HDPCs 中 NLRP6 表达的影响。最后，通过慢病毒短发夹 RNA 沉默 NLRP6 基因，探讨 NLRP6 对 LPS 诱导的白细胞介素（IL）-1β的影响。
NLRP6 主要表达于健康牙髓的成牙本质细胞层和血管中，以及炎症牙髓中的浸润免疫细胞和纤维母细胞。进一步的免疫荧光双染显示，牙髓血管中的周细胞和内皮细胞、炎症牙髓中的巨噬细胞和 T 细胞以及纤维母细胞均表达 NLRP6。培养的 HDPCs 中基本表达 NLRP6，并受 LPS 刺激上调。HDPCs 中 NLRP6 的敲低显著抑制了 LPS 诱导的 IL-1β表达。
本研究揭示了 NLRP6 在人牙髓组织中的表达和分布。此外，NLRP6 也基本表达于培养的 HDPCs 中，并可受 LPS 刺激上调，提示 NLRP6 参与牙髓免疫反应。
