Shi Lei, Fu Shanqi, Fahim Sidra, Pan Shuang, Lina He, Mu Xiaodan, Niu Yumei
Department of Endodontics, The First Affiliated Hospital of Harbin Medical University, 143 Yiman Street, Nangang District, Harbin, 150001, China; Oral Biomedical Research Institute of Harbin Medical University, 143 Yiman Street, Nangang District, Harbin, 150001, China.
Department of Endodontics, The First Affiliated Hospital of Harbin Medical University, 143 Yiman Street, Nangang District, Harbin, 150001, China.
Arch Oral Biol. 2017 Mar;75:48-54. doi: 10.1016/j.archoralbio.2016.12.005. Epub 2016 Dec 15.
The dissemination of stem cells into tissues requiring inflammatory and reparative response is fundamentally dependent upon their chemotactic migration. Expression of TNF-α is up regulated in inflamed pulps. Dental pulp cells are also known to express integrin α6 subunit. Expression of integrin subunit α6 has been linked to the acquisition of migratory potential in a wide variety of cell types in both pathological and physiological capacities. Therefore, in this study we examined the effects of a pleiotropic cytokine TNF-α on the migration of hDPSCs and investigated its relationship with expression of integrin α6 in hDPSCs during chemotactic migration.
hDPSC cultures were established. Protein expression profile of α6 integrin subunit was determined. Effect of exogenous TNF-α (50ng/mL) on hDPSCs' migration potential was evaluated by transwell inserts and in vitro scratch assay. Upregulation/downregulation of TNF-α mediated migration was assayed in presence/absence of integrin α6 respectively. To suppress integrin α6 expression, cells were transfected with integrin α6 siRNA and then cell migration and cytoskeletal changes were evaluated.
Our results showed significant increase of hDPSCs' migration after stimulation with TNF-α. By knockdown of integrin α6, which is upregulated by TNF-α, we observed a decrease in the TNF-α directed chemotaxis of hDPSCs.
In this study, we show that activation of integrin α6 brought about by TNF-α led to an increase in migratory activity in DPSCs in vitro thus describing a novel association between a cytokine TNF-α and α6 chain of an adhesion receptor integrin in regulating migration of hDPSCs.
干细胞向需要炎症和修复反应的组织中的扩散从根本上取决于它们的趋化性迁移。肿瘤坏死因子-α（TNF-α）在炎症牙髓中表达上调。牙髓细胞也已知表达整合素α6亚基。整合素亚基α6的表达与多种细胞类型在病理和生理能力下获得迁移潜能有关。因此，在本研究中，我们检测了多效细胞因子TNF-α对人牙髓干细胞（hDPSCs）迁移的影响，并研究了其在趋化性迁移过程中与hDPSCs中整合素α6表达的关系。
建立hDPSC培养物。测定α6整合素亚基的蛋白质表达谱。通过Transwell小室和体外划痕试验评估外源性TNF-α（50ng/mL）对hDPSCs迁移潜能的影响。分别在存在/不存在整合素α6的情况下检测TNF-α介导的迁移的上调/下调。为了抑制整合素α6的表达，用整合素α6 siRNA转染细胞，然后评估细胞迁移和细胞骨架变化。
我们的结果显示，TNF-α刺激后hDPSCs的迁移显著增加。通过敲低被TNF-α上调的整合素α6，我们观察到hDPSCs的TNF-α定向趋化性降低。
在本研究中，我们表明TNF-α引起的整合素α6激活导致体外DPSCs迁移活性增加，从而描述了细胞因子TNF-α与粘附受体整合素的α6链在调节hDPSCs迁移中的新关联。
