Related Experiment Video
Updated: Feb 11, 2026

In vitro Induction of Human Dental Pulp Stem Cells Toward Pancreatic Lineages
Published on: September 25, 2021
Human Dental Pulp Cells Express Cellular Markers for Inflammation and Hard Tissue Formation in Response to Bacterial
Akina Sugiuchi1, Yousuke Sano1, Masahiro Furusawa1
1Department of Endodontics, Tokyo Dental College, Tokyo, Japan.
Introduction:
Lipopolysaccharide (LPS) is a major component of the outer membranes of gram-negative bacteria associated with deep dental caries and pulpitis. When bacteria invade dentinal tubes and dentin is continually destroyed, tertiary dentin is formed by preexisting odontoblasts. However, the relationship between LPS and tertiary dentin formation remains unclear. We investigated whether LPS stimulation induces the formation of hard tissue in human dental pulp cells (hDPCs).
Methods:
Immortalized hDPCs were cultured, and Escherichia coli-derived LPS (1 μg/mL) was incorporated into the culture medium. Samples were obtained after 0, 1, 3, 7, 14, and 21 days, and messenger RNA expression of IL-1β, IL-6, Wnt5a, Runx2, ALP, and alkaline phosphatase (ALP) activity was investigated.
Results:
Quantitative real-time polymerase chain reaction revealed higher messenger RNA expression levels of IL-1β and IL-6 in the LPS group on 1 day (P < .05). The expression levels of dentinogenesis-related markers including Wnt5a, Runx2, and ALP were higher in the LPS group (2.0-, 4.7- and 10.0-fold, respectively) than that in the control group at 14 days (P < .01). ALP activity was significantly stronger in the LPS group than in the control group at 21 days (P < .01). Treatment of Box5, an antagonist of Wnt5a, showed a decreased expression of Runx2 and ALP (P < .05).
Conclusions:
These results indicate that LPS stimulation induces the gene expression of inflammatory cytokines and hard tissue formation through Wnt5a signaling pathways in hDPCs.
More Related Videos
11:50Isolation, Propagation, and Prion Protein Expression During Neuronal Differentiation of Human Dental Pulp Stem Cells
Published on: March 18, 2019
14:52Isolation, Characterization and Comparative Differentiation of Human Dental Pulp Stem Cells Derived from Permanent Teeth by Using Two Different Methods
Published on: November 24, 2012
Related Concept Videos
Inflammation
Inflammatory Response I: Vascular and Cellular
Cell Specific Gene Expression
Toughness and Hardness of Aggregate
Bacterial Signaling
Elastin is Responsible for Tissue Elasticity
Ligaments and tendons are made of dense regular connective tissue, but in ligaments not all fibers are parallel. Dense regular elastic tissue contains elastin fibers and...