Periodontal bone defects, primarily caused by periodontitis, are highly prevalent in clinical settings and manifest as bone fenestration, dehiscence, or attachment loss, presenting a significant challenge to oral health. In regenerative medicine, harnessing developmental principles for tissue repair offers promising therapeutic potential. Of particular interest is the condensation of progenitor cells, an essential event in organogenesis that has inspired clinically effective cell aggregation approaches in dental regeneration. However, the precise cellular coordination mechanisms during condensation and regeneration remain elusive. Here, taking the tooth as a model organ, we employed single-cell RNA sequencing to dissect the cellular composition and heterogeneity of human dental follicle and dental papilla, revealing a distinct Platelet-derived growth factor receptor alpha (PDGFRA) mesenchymal stem/stromal cell (MSC) population with remarkable odontogenic potential. Interestingly, a reciprocal paracrine interaction between PDGFRA⁺ dental follicle stem cells (DFSCs) and CD31⁺ Endomucin⁺ endothelial cells (ECs) was mediated by Vascular endothelial growth factor A (VEGFA) and Platelet-derived growth factor subunit BB (PDGFBB). This crosstalk not only maintains the functionality of PDGFRA⁺ DFSCs but also drives specialized angiogenesis. In vivo periodontal bone regeneration experiments further reveal that communication between PDGFRA⁺ DFSC aggregates and recipient ECs is essential for effective angiogenic-osteogenic coupling and rapid tissue repair. Collectively, our results unravel the importance of MSC-EC crosstalk mediated by the VEGFA and PDGFBB-PDGFRA reciprocal signaling in orchestrating angiogenesis and osteogenesis. These findings not only establish a framework for deciphering and promoting periodontal bone regeneration in potential clinical applications but also offer insights for future therapeutic strategies in dental or broader regenerative medicine.
Receptor, Platelet-Derived Growth Factor alpha/metabolism* ; Humans ; Neovascularization, Physiologic/physiology* ; Dental Sac/cytology* ; Single-Cell Analysis ; Transcriptome ; Mesenchymal Stem Cells/metabolism* ; Bone Regeneration ; Animals ; Dental Papilla/cytology* ; Periodontium/physiology* ; Stem Cells/metabolism* ; Regeneration ; Angiogenesis

A splicing mutation in VPS4B can cause dentin dysplasia type I (DD-I), a hereditary autosomal-dominant disorder characterized by rootless teeth, the etiology of which is genetically heterogeneous. In our study, dental follicle cells (DFCs) were isolated and cultured from a patient with DD-I and compared with those from an age-matched, healthy control. In a previous study, this DD-I patient was confirmed to have a loss-of-function splicing mutation in VPS4B (IVS7 + 46C > G). The results from this study showed that the isolated DFCs were vimentin-positive and CK14-negative, indicating that the isolated cells were derived from the mesenchyme. DFCs harboring the VPS4B mutation had a significantly higher proliferation rate from day 3 to day 8 than control DFCs, indicating that VPS4B is involved in cell proliferation. The cells were then replenished with osteogenic medium to investigate how the VPS4B mutation affected osteogenic differentiation. Induction of osteogenesis, detected by alizarin red and alkaline phosphatase staining in vitro, was decreased in the DFCs from the DD-I patient compared to the control DFCs. Furthermore, we also found that the VPS4B mutation in the DD-I patient downregulated the expression of osteoblast-related genes, such as ALP, BSP, OCN, RUNX2, and their encoded proteins. These outcomes confirmed that the DD-I-associated VPS4B mutation could decrease the capacity of DFCs to differentiate during the mineralization process and may also impair physiological root formation and bone remodeling. This might provide valuable insights and implications for exploring the pathological mechanisms underlying DD-I root development.
ATPases Associated with Diverse Cellular Activities ; genetics ; Case-Control Studies ; Cell Differentiation ; genetics ; Cells, Cultured ; Dental Sac ; cytology ; Dentin Dysplasia ; genetics ; pathology ; physiopathology ; Endosomal Sorting Complexes Required for Transport ; genetics ; Humans ; Mutation ; genetics ; Osteogenesis ; genetics ; RNA Splicing ; genetics

Bone formation is important for the reconstruction of bone-related structures in areas that have been damaged by inflammation. Inflammatory conditions such as those that occur in patients with rheumatoid arthritis, cystic fibrosis, and periodontitis have been shown to inhibit osteoblastic differentiation. This study focussed on dental follicle stem cells (DFSCs), which are found in developing tooth germ and participate in the reconstruction of alveolar bone and periodontal tissue in periodontal disease. After bacterial infection of inflamed dental tissue, the destruction of bone was observed. Currently, little is known about the relationship between the inflammatory environment and bone formation. Osteogenic differentiation of inflamed DFSCs resulted in decreased alkaline phosphatase (ALP) activity and alizarin red S staining compared to normal DFSCs. Additionally, in vivo transplantation of inflamed and normal DFSCs demonstrated severe impairment of osteogenesis by inflamed DFSCs. Protein profile analysis via liquid chromatography coupled with tandem mass spectrometry was performed to analyse the differences in protein expression in inflamed and normal tissue. Comparison of inflamed and normal DFSCs showed significant changes in the level of expression of transforming growth factor (TGF)-β2. Porphyromonas gingivalis (P.g.)-derived lipopolysaccharide (LPS) was used to create in vitro inflammatory conditions similar to periodontitis. The osteogenic differentiation of LPS-treated DFSCs was suppressed, and the cells displayed low levels of TGF-β1 and high levels of TGF-β2. DFSCs treated with TGF-β2 inhibitors showed significant increases in alizarin red S staining and ALP activity. TGF-β1 expression was also increased after inhibition of TGF-β2. By examining inflamed DFSCs and LPS-triggered DFSCs, these studies showed both clinically and experimentally that the increase in TGF-β2 levels that occurs under inflammatory conditions inhibits bone formation.
Adolescent ; Alkaline Phosphatase ; metabolism ; Animals ; Cell Differentiation ; Cell Proliferation ; Cell Survival ; Cells, Cultured ; Dental Sac ; cytology ; metabolism ; Down-Regulation ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Immunohistochemistry ; Male ; Mass Spectrometry ; Mice ; Nitric Oxide ; metabolism ; Osteogenesis ; drug effects ; Polymerase Chain Reaction ; Staining and Labeling ; Stem Cells ; cytology ; metabolism ; Transforming Growth Factor beta2 ; pharmacology ; Young Adult

OBJECTIVEThis study explores the effects of different fibrin glue combination modes on the survival, proliferation, and apoptosis of dental follicle cells (DFCs), as well as to evaluate the feasibility and effectiveness of fibrin glue as transplantation material.

METHODSThe membranes of surviving DFCs were marked using 3,3'-dioctadecyloxa carbocyanine perchlorate (DIO), and the cell number was counted by using ImageJ2x software. The apoptotic cells were marked with prodium iodide (PI).

RESULTSCompared with that of the 3D-2 and 2D-1 groups, the degradation speed of the 3D-1 group was the slowest. DFCs could survive and grow well in fibrinogen with a concentration of 15 mg · mL⁻¹ supplemented with thrombin with a concentration of 2 U · mL⁻¹. In particular, the 3D-1 combination mode was significantly conducive to cell proliferation and stretching.

CONCLUSIONFibrin glue can be used as an effective cell transplantation material. The different combination modes have certain effects on cell proliferation. The 3D-1 combination mode is more conducive to the survival and proliferation of DFCs than other modes.

Apoptosis ; Cell Proliferation ; Cell Survival ; Dental Sac ; cytology ; Fibrin Tissue Adhesive ; pharmacology ; Fibrinogen ; Humans ; Thrombin

OBJECTIVETo construct SD rat immortalized dental follicle cells (rDFC) induced by simian virus 40 large tumor antigen (SV40Tag) gene to provide a reliable cell source for periodontal tissue engineering research.

METHODSThe rDFC was isolated by tissue mass method combined with enzyme digestion method and evaluated by immunohistochemistry. Cell293 were transfected with plasmid pSSR69/pAmpho containing SV40Tag gene by mediating liposome. Normal rDFC were infected with virus-contained supernate and the successfully transfected cell lines were screened with hygromycin, and positive clones were cultured. While non-transfected cells served as negative controls, the cell morphology was observed, the proliferation characteristics was evaluated by calculating cell population. The expression of SV40Tag gene and telomerase in cells was detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blotting respectively. The biological property of immortalized rDFC was assessed with calculating formation rate of flat cloning, soft agar colony formation test and tumor-forming test.

RESULTSMorphology of immortalized rDFC was not different from that of normal rDFC. The RT-PCR results of SV40Tag revealed amplification band at 357 bp, while no band was seen in the normal cells. The expression of telomerase in immortalized rDFC was higher than that in normal rDFC. The two groups had no significant difference in growth curves, but the immortalized rDFC exhibited stronger proliferative activity. No significant differences of formation rate in flat cloning were observed between the immortalized rDFC [34% (33/96)] and normal rDFC at passage four [22% (21/96)] (χ(2) = 3.71, P > 0.05). No cell cloning was seen in soft agar and the tumor formation was not observed in nude mice.

CONCLUSIONSThe rDFC induced by SV40Tag gene could be cultured and passaged in vitro, which retained the stable proliferation and differentiation characteristics and could be used for periodontal tissue engineering research.

Animals ; Antigens, Viral, Tumor ; genetics ; metabolism ; Cell Differentiation ; Cell Proliferation ; Cell Transformation, Viral ; Cells, Cultured ; Dental Sac ; cytology ; immunology ; metabolism ; HEK293 Cells ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Plasmids ; Rats ; Rats, Sprague-Dawley ; Simian virus 40 ; genetics ; immunology ; Telomerase ; metabolism ; Transfection

AIMTo detect the expression of HSP25 in rat dental follicles both in vivo and vitro, and explore the underlying mechanism of HSP25 on the proliferation and differentiation of rat dental follicle cells (DFCs).

METHODOLOGYImmunohistochemistry was performed to detect the expression of HSP25 in mandibles of postnatal rats on days 1, 3, 5, 7, 9 and 11 in vivo. In vitro, the expression of HSP25 in DFCs was detected by an indirect immunofluorescence assay. Thiazolyl blue tetrazolium bromide (MTT) assay, flow cytometry and alkaline phosphatase (ALP) assay were used to identify the time-course effect mediated by different concentrations of recombinant murine HSP25 of 0, 1, 10, 50 and 100 ng/mL on rat DFCs.

RESULTSExpression of HSP25 was not detected in dental follicles of the rats until day 5 after birth, but became up-regulated in a time-dependent manner till day 11. HSP25 was detected in the cytoplasm of cultured rat DFCs. No significant difference could be observed in the proliferation of DFCs after stimulation with different concentrations of HSP25 on days 1, 2 and 3 (P > 0.05). HSP25 at concentrations of 50 ng/mL and 100 ng/mL up-regulated the ALP activity of DFCs on day 9 (P < 0.05).

CONCLUSIONHSP25-immunoreactivity increased chronologically during the development of dental follicles. The protein had no significant effect on cell proliferation but may play a role in cementoblast/osteoblast differentiation of DFCs.

Alkaline Phosphatase ; analysis ; Ameloblasts ; cytology ; Animals ; Cell Culture Techniques ; Cell Differentiation ; physiology ; Cell Proliferation ; Coloring Agents ; Cytoplasm ; ultrastructure ; Dental Sac ; cytology ; growth & development ; Flow Cytometry ; Fluorescent Antibody Technique, Indirect ; HSP27 Heat-Shock Proteins ; analysis ; physiology ; Odontoblasts ; cytology ; Rats ; Rats, Sprague-Dawley ; Tetrazolium Salts ; Thiazoles ; Tooth Germ ; cytology ; Up-Regulation ; physiology

Tooth loss compromises human oral health. Although several prosthetic methods, such as artificial denture and dental implants, are clinical therapies to tooth loss problems, they are thought to have safety and usage time issues. Recently, tooth tissue engineering has attracted more and more attention. Stem cell based tissue engineering is thought to be a promising way to replace the missing tooth. Mesenchymal stem cells (MSCs) are multipotent stem cells which can differentiate into a variety of cell types. The potential MSCs for tooth regeneration mainly include stem cells from human exfoliated deciduous teeth (SHEDs), adult dental pulp stem cells (DPSCs), stem cells from the apical part of the papilla (SCAPs), stem cells from the dental follicle (DFSCs), periodontal ligament stem cells (PDLSCs) and bone marrow derived mesenchymal stem cells (BMSCs). This review outlines the recent progress in the mesenchymal stem cells used in tooth regeneration.
Adult Stem Cells ; physiology ; Bone Marrow Cells ; cytology ; Dental Papilla ; cytology ; Dental Pulp ; cytology ; Dental Sac ; cytology ; Humans ; Mesenchymal Stromal Cells ; physiology ; Multipotent Stem Cells ; physiology ; Periodontal Ligament ; cytology ; Regeneration ; physiology ; Tissue Engineering ; Tooth ; physiology ; Tooth, Deciduous ; cytology

OBJECTIVETo establish a method for culturing dental follicle cells of rat and observe the growth characteristics of the cultured cells in vitro.

METHODSDental follicle and associated enamel organs were dissected from the first and second mandibular molars of 6-7-day-old rats, and then cultured in vitro. Purified dental follicle cells derived from the third or the fourth passage cells were utilized in the following experiments. The shape and ultrastructure of dental follicle cells were observed by light-microscopy and transmission electron microscopy. Immunocytochemistry was used to detect the expression of vimentin, type I collagen and fibronectin.

RESULTSThe cultured cells were fibroblastic in shape, elongate with processes, and transmission electron microscopy revealed that they contained electron-dense granules, an abundant rough endoplasmic reticulum, but did not form desmosomes. Vimentin, type I collagen and fibronectin were present in dental follicle cell.

CONCLUSIONThe dental follicle cells of rat could be successfully cultured in vitro and the cultured cells had the same characteristics of dental follicle cells of normal rat.

Animals ; Animals, Newborn ; Cells, Cultured ; Collagen Type I ; analysis ; Dental Sac ; chemistry ; cytology ; ultrastructure ; Fibroblasts ; cytology ; ultrastructure ; Fibronectins ; analysis ; Immunohistochemistry ; Molar ; chemistry ; cytology ; Rats ; Rats, Sprague-Dawley ; Tooth Eruption ; Vimentin ; analysis

OBJECTIVETo study localization and expression of CSF-1 receptor protein, in order to discover the CSF-1 and IL-1alpha effects on CSF-1 receptor mRNA levels and to determine if the autocrine effect is inhibited through the CSF-1 receptor.

METHODSImmunolocalization of CSF-1 receptor in the cultured dental follicle cells and in mandibles of the post-natal rats from day 1 to 11 were performed. The effects of different concentrations of CSF-1, IL-1alpha on CSF-1 receptor gene expression were detected by means of RT-PCR.

RESULTSCultured dental follicle cells were immunostained for the CSF-1 receptor. In vivo, immunostaining showed that the CSF-1 receptor was present in the dental follicle of the first mandibular molar at early post-natally and was either absent or greatly reduced by day 11 post-natally. High concentrations of cvCSF-1 reduced the gene expression of the CSF-1 receptor. IL-1alpha had no effects on CSF-1 receptor mRNA levels.

CONCLUSIONSThe expression of CSF-1 receptor reaches a peak early post-natally in the dental follicle of the first mandibular molar of the rat and then subsequently declines. High concentrations of CSF-1 inhibits the expression of CSF-1 receptor, IL-1alpha has no effect on the expression of CSF-1 receptor mRNA.

Animals ; Cells, Cultured ; Dental Sac ; chemistry ; cytology ; Immunohistochemistry ; Interleukin-1 ; pharmacology ; Macrophage Colony-Stimulating Factor ; pharmacology ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Receptor, Macrophage Colony-Stimulating Factor ; analysis ; genetics