Human Dental Pulp Stem Cells and Gingival Mesenchymal Stem Cells Display Action Potential Capacity In Vitro after Neuronogenic Differentiation.

The potential of human mesenchymal stromal/stem cells (MSCs) including oral stem cells (OSCs) as a cell source to derive functional neurons has been inconclusive. Here we tested a number of human OSCs for their neurogenic potential compared to non-OSCs and employed various neurogenic induction methods. OSCs including dental pulp stem cells (DPSCs), gingiva-derived mesenchymal stem cells (GMSCs), stem cells from apical papilla and non-OSCs including bone marrow MSCs (BMMSCs), foreskin fibroblasts and dermal fibroblasts using non-neurosphere-mediated or neurosphere-mediated methods to guide them toward neuronal lineages.

Human dental stem cell derived transgene-free iPSCs generate functional neurons via embryoid body-mediated and direct induction methods.

Induced pluripotent stem cells (iPSCs) give rise to neural stem/progenitor cells, serving as a good source for neural regeneration. Here, we established transgene-free (TF) iPSCs from dental stem cells (DSCs) and determined their capacity to differentiate into functional neurons in vitro. Generated TF iPSCs from stem cells of apical papilla and dental pulp stem cells underwent two methods-embryoid body-mediated and direct induction, to guide TF-DSC iPSCs along with H9 or H9 Syn-GFP (human embryonic stem cells) into functional neurons in vitro.

Phosphatidylinositol 3-Kinase and Protein Kinase C Signaling Pathways Are Involved in Stromal Cell-derived Factor-1α-mediated Transmigration of Stem Cells from Apical Papilla.

Introduction: Previously, we have shown that stem cells from apical papilla (SCAPs) can be chemoattracted by stromal cell-derived factor-1α (SDF-1α). The purpose of this study was to investigate the intracellular signaling pathways involved in SDF-1α-mediated migration of SCAPs.

Methods: Chemotaxis assays were performed to assess the effect of phosphatidylinositol 3-kinase (PI3K) and protein kinase C (PKC) signaling pathways in the SDF-1α-mediated migration of SCAPs using inhibitors of PI3K (LY294002) or PKC (GF109203X).

CXC Chemokine Receptor 4 Is Expressed Paravascularly in Apical Papilla and Coordinates with Stromal Cell-derived Factor-1α during Transmigration of Stem Cells from Apical Papilla.

Introduction: Stem cells from the apical papilla (SCAPs) at the apex may be attracted into the root canal space as a cell source for pulp-dentin regeneration. To test this possibility, we used in vitro transmigration models to investigate whether SCAPs can be chemoattracted by the delivery of the chemotactic cytokine stromal cell-derived factor-1α (SDF-1α).

Methods: We first examined the expression of CXC chemokine receptor 4 (CXCR4) for SDF-1α in the apical papilla and in cultured SCAPs using immunofluorescence, reverse-transcription polymerase chain reaction (RT-PCR), and flow cytometric analyses.

[Notch activation delayed ageing of human dental pulp cells].

Objective: To establish model of dental pulp cells with activated Notch signaling pathway, and investigate the effect of activating Notch signaling pathway on senescence of human dental pulp cells in vitro.

Methods: Human dental pulp cells were isolated, cultured as usual, and used from the 4(th) passage. The cells were divided into the activated group and the negative control group.

[Effects of DAPT on proliferation of human dental pulp cells and Notch signaling pathway].

Objective: To explore whether the γ-secretase inhibitor N-[N-(3,5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester (DAPT) could inhibit Notch signaling pathway in human dental pulp cells, and its effects on the proliferation ability of the cells.

Methods: Human dental pulp cells were primarily cultured from healthy premolars or wisdom teeth extracted intactly. The γ-secretase inhibitor DAPT (5 μmol/L) was added to the culture medium from passage 4 to the end.

Establishment of transgene-free induced pluripotent stem cells reprogrammed from human stem cells of apical papilla for neural differentiation.

Introduction: Induced pluripotent stem cells (iPSCs) are a potent cell source for neurogenesis. Previously we have generated iPSCs from human dental stem cells carrying transgene vectors. These exogenous transgenes may affect iPSC behaviors and limit their clinical applications.

Involvement of Notch signalling pathway in senescence of human dental pulp cells.

Objective: To evaluate whether the Notch signalling pathway is involved in the senescence of human dental pulp cells.

Methods: Human dental pulp cells were isolated and cultured. The Notch signalling pathway was blocked by adding DAPT (N-[N-(3,5-difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester, γ-secretase inhibitor, 5 μmol/L) into the culture medium.

[Infiltration of CD(4)(+)CD(25)(+) T cells into the allergic asthmatic airways caused by house dust mite antigen administration.].

Objective: To investigate whether house dust mite (HDM) could induce CD(4)(+) CD(25)(+) T cells infiltration into asthmatic airways in patients vivo.

Methods: Ten subjects with asthma underwent initial bronchoscopy during which normal saline and HDM were administered to two sublobar segments separately. The second bronchoscopy were carried out and bronchoal lavage fluid from HDM-challenged sites and saline-challenged sites were separately taken 24 h later.

[Observation of multi-directional differentiation capability of dental papilla cells].

Objective: To study the types of progenitors in dental papilla cells(DPCs) and their differentiation characteristics.

Methods: DPCs of the mandibular first molars of four-day post-natal SD rats were isolated and cultured. The expression of osteocalcin (OCN) and dentin sialoprotein (DSP) were detected using DAB kit.

[Acidic fibroblast growth factor for preventing motor endplate degeneration and muscular atrophy after motor nerve injury: a morphological and electrophysiological study].

Objective: To explore measures to prevent motor endplate degeneration and muscular atrophy after motor nerve injury.

Methods: Thirty Sprague-Dawley rats were randomized into 3 equal groups. In two of the groups, the right common peroneal nerves of the rats were transected and immediately sutured with implantation of collagen gel carrier of acidic fibroblast growth factor (aFGF) or the empty carrier into the denervated tibialis anterior muscles.