The role of integrin-α5 in the proliferation and odontogenic differentiation of human dental pulp stem cells.
BACKGROUND
It has been reported that integrin-α5 (ITGA5) activity is related to cell proliferation, differentiation, migration, and organ development. However, the involvement of ITGA5 in the biological functions of human dental pulp stem cells (hDPSCs) has not been explored. The aim of this study was to investigate the role of ITGA5 in the proliferation and odontogenic differentiation of hDPSCs.


METHODS
We knocked down ITGA5 in hDPSCs using lentivirus-mediated ITGA5 short hairpin RNA (shRNA). Changes in the proliferation in hDPSCs infected with lentiviruses expressing ITGA5-specific shRNA or negative control shRNA were examined using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 5-ethynyl-2'-deoxyuridine labeling. Both ITGA5 knockdown cells and shMock cells were cultured in mineralization medium for 3 weeks, and the differentiation of cells was detected with alizarin red S staining. The expression of odontogenic differentiation-related molecular markers was assessed using real-time polymerase chain reaction and Western blot assays.


RESULTS
The knockdown of ITGA5 decreased the proliferation capacity of hDPSCs. ITGA5 shRNA promoted odontogenic differentiation of hDPSCs with the enhanced formation of mineralized nodules. It also up-regulated the messenger RNA expression of multiple markers of odontogenesis and the expression of dentin sialophosphoprotein protein.


CONCLUSIONS
These findings suggest that ITGA5 plays an important role in maintaining hDPSCs in a proliferative state. The inhibition of ITGA5 signaling promotes the odontogenic differentiation of hDPSCs.
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China.
Li
L
Cui
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China.
Shuaimei
S
Xu
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China.
Dandan
D
Ma
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China.
Jie
J
Gao
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China.
Ying
Y
Liu
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China.
Jing
J
Yue
Department of Stomatology, Nanfang Hospital, Guangzhou, China; College of Stomatology, Southern Medical University, Guangzhou, China. Electronic address: bulingwu1958@163.com.
Buling
B
Wu
D000880:Anthraquinones; D002113:Calcification, Physiologic / Q000235:genetics / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D002478:Cells, Cultured; D004396:Coloring Agents; D003782:Dental Pulp / Q000166:cytology*; D003857:Deoxyuridine / Q000031:analogs & derivatives; D016326:Extracellular Matrix Proteins / Q000032:analysis; D055785:Gene Knockdown Techniques; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D039482:Integrin alpha5 / Q000235:genetics / Q000502:physiology*; D016086:Lentivirus / Q000235:genetics; D009805:Odontogenesis / Q000235:genetics / Q000502:physiology*; D010750:Phosphoproteins / Q000032:analysis; D034741:RNA, Small Interfering / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D012795:Sialoglycoproteins / Q000032:analysis; D013234:Stem Cells / Q000502:physiology*; D013778:Tetrazolium Salts; D013844:Thiazoles; D000099311:Dentin Sialophosphoprotein
D000880:Anthraquinones; D004396:Coloring Agents; D003857:Deoxyuridine; D016326:Extracellular Matrix Proteins; D039482:Integrin alpha5; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D012795:Sialoglycoproteins; D013778:Tetrazolium Salts; D013844:Thiazoles; D000099311:Dentin Sialophosphoprotein; C004468:Alizarin Red S; C022616:thiazolyl blue; C031086:5-ethynyl-2'-deoxyuridine
Differentiation; human dental pulp stem cells; integrin-α5; proliferation