Human Dental Pulp Stem Cells Research Articles

In vitro biocompatibility of ammonia-free silver fluoride products on human dental pulp stem cells

ObjectivesSilver fluoride (SF) is a preventive and therapeutic option for dental pathological processes involving structural alterations of the hard tissues, either during their formation or those caused by caries or other pathological reasons. This study aimed to compare the biological properties of two commercial SF products, one of them with ammonium (Riva Star; SDF) and the other ammonium-free (Riva Star Aqua; AgF), both with or without potassium iodide (KI), by the assessment of the cytotoxicity of the materials’ eluates. MethodsHuman dental pulp stem cells (hDPSCs) were obtained from healthy 18–23-year-old donors. Three dilutions were prepared for the tested materials (0.005%, 0.0005%, and 0.0001%). The following groups were assessed: (AgF, AgF+KI, SDF, SDF+KI, KI, negative control). A series of cytocompatibility assays were performed: MTT assay, IC50 assay, wound healing (migration) assay, cell cytoskeleton staining, analysis of cell apoptosis and necrosis, and reactive oxygen species production. The normality in the distribution of the data was previously confirmed via a Q-Q plot. Statistical significance was tested using one way ANOVA and Tukey's post hoc test. ResultsThe incorporation of KI improved the cytocompatibility of both SF products in terms of viability, migration, morphology, apoptosis, and reactive oxygen species production. This difference was higher in the AgF group. The lowest dilutions of SF+KI and AgF+KI showed a similar cytocompatibility to that of the control group (MTT assay (p > 0.05 after 24, 48, and 72 h of culture); migration assay (p > 0.05 after 24, 48, and 72 h of culture); reactive oxygen species production (p > 0.05 after 72 h of culture). SignificanceRiva Star Aqua shows lower cytotoxicity than Riva Star on hDPSCs. It can be considered as a good alternative in the conservative treatment of dental caries and in the preservation and remineralisation of viable dentine tissue.

Micropattern‐Based Stem Cell Gym: Mechanical Memory Enhanced Stemness Maintenance of Human Dental Pulp Stem Cells and Nerve Regeneration (Adv. Funct. Mater. 49/2023)

Micropattern‐Based Stem Cell Gym: Mechanical Memory Enhanced Stemness Maintenance of Human Dental Pulp Stem Cells and Nerve Regeneration (Adv. Funct. Mater. 49/2023)

The Cytotoxic Assessment of Antibacterial-Enhanced Mineral Trioxide Aggregate Compared to Commercially Available Bioceramic Cements by Using Methyl-Thiazoldiphenyl-Tetrazolium (MTT) Assay on Human Dental Pulp Stem Cells: An In Vitro Study.

Background and objective Preserving the vitality of the tooth is of prime significance during therapies such as direct pulp capping and pulpotomy that promote tertiary dentine formation and healing of pulp stumps. Procedures like apexogenesis and apexification also stimulate dentin and bone formation for root growth and closure. Conventional mineral trioxide aggregate (MTA) has good biocompatible and physical properties like longer setting time, presence of a cytotoxic component, i.e., tricalcium aluminate (TCA), moderate compressive strength, and moderate antimicrobial activity. Eliminating TCA and the addition of antibacterial components would improve the properties of the cement. In this study, we aimed to assess the cytotoxicity of MTA Angelus, Biodentine, and two antibacterial-enhanced MTAs by using methyl-thiazoldiphenyl-tetrazolium (MTT) assay. Materials and methods Human dental pulp was extirpated from extracted third molars, and human dental pulp stem cells(HDPSCs)were isolated and characterized by flow cytometry. HDPSCs were treated with MTA, Biodentine, or two antibacterial-enhanced MTAs depending on the study group. The control group constituted the untreated HDPSCs. The cell viability of HDPSCs was assessed using an MTT assay on days one, three, and seven. Results Varied levels of cytotoxicity were noticed atdifferent time periods assessed using the tested materials, which was statistically significant (p=0.01). At alltime periods assessed, the highest cell viability was noticed with Biodentine (88.7% on the first day, 80.4% on the third day, and 91.8% on the seventh day). Antibacterial-enhanced MTAs, either added with metronidazole or doxycycline, had more mean viable cells compared to conventional MTA on the third and seventh day (p=0.043 and 0.018 respectively). Conclusion Antibacterial-enhanced MTAsshowed reduced cytotoxic properties when compared to conventional MTA. Biodentine was associated with the highestcell viability at all time periods.

In Vitro Chondrogenesis Induction by Short Peptides of the Carboxy-Terminal Domain of Transforming Growth Factor β1.

Τransforming growth factor β1 (TGF-β1) comprises a key regulator protein in many cellular processes, including in vivo chondrogenesis. The treatment of human dental pulp stem cells, separately, with Leu83-Ser112 (C-terminal domain of TGF-β1), as well as two very short peptides, namely, 90-YYVGRKPK-97 (peptide 8) and 91-YVGRKP-96 (peptide 6) remarkably enhanced the chondrogenic differentiation capacity in comparison to their full-length mature TGF-β1 counterpart either in monolayer cultures or 3D scaffolds. In 3D scaffolds, the reduction of the elastic modulus and viscous modulus verified the production of different amounts and types of ECM components. Molecular dynamics simulations suggested a mode of the peptides' binding to the receptor complex TβRII-ALK5 and provided a possible structural explanation for their role in inducing chondrogenesis, along with endogenous TGF-β1. Further experiments clearly verified the aforementioned hypothesis, indicating the signal transduction pathway and the involvement of TβRII-ALK5 receptor complex. Real-time PCR experiments and Western blot analysis showed that peptides favor the ERK1/2 and Smad2 pathways, leading to an articular, extracellular matrix formation, while TGF-β1 also favors the Smad1/5/8 pathway which leads to the expression of the metalloproteinases ADAMTS-5 and MMP13 and, therefore, to a hypertrophic chondrocyte phenotype. Taken together, the two short peptides, and, mainly, peptide 8, could be delivered with a scaffold to induce in vivo chondrogenesis in damaged articular cartilage, constituting, thus, an alternative therapeutic approach for osteoarthritis.

Changes in osteogenesis by human dental pulp stem cells on porcine decellularised adipose tissue solid foams of different porosity

Changes in osteogenesis by human dental pulp stem cells on porcine decellularised adipose tissue solid foams of different porosity

Osteogenic Potential of Human Dental Pulp Stem Cells (hDPSCs) Growing on Poly L-Lactide-Co-Caprolactone and Hyaluronic Acid (HYAFF-11TM) Scaffolds

Bone tissue engineering using different scaffolds is a new therapeutic approach in regenerative medicine. This study explored the osteogenic potential of human dental pulp stem cells (hDPSCs) grown on a hydrolytically modified poly(L-lactide-co-caprolactone) (PLCL) electrospun scaffold and a non-woven hyaluronic acid (HYAFF-11™) mesh. The adhesion, immunophenotype, and osteogenic differentiation of hDPSCs seeded on PLCL and HYAFF-11™ scaffolds were analyzed. The results showed that PLCL and HYAFF-11™ scaffolds significantly supported hDPSCs adhesion; however, hDPSCs’ adhesion rate was significantly higher on PLCL than on HYAFF-11™. SEM analysis confirmed good adhesion of hDPSCs on both scaffolds before and after osteogenesis. Alizarin red S staining showed mineral deposits on both scaffolds after hDPSCs osteogenesis. The mRNA levels of runt-related transcription factor 2 (Runx2), collagen type I (Coll-I), osterix (Osx), osteocalcin (Ocn), osteopontin (Opn), bone sialoprotein (Bsp), and dentin sialophosphoprotein (Dspp) gene expression and their proteins were higher in hDPSCs after osteogenic differentiation on both scaffolds compared to undifferentiated hDPSCs on PLCL and HYAFF-11™. These results showed that PLCL scaffolds provide a better environment that supports hDPSCs attachment and osteogenic differentiation than HYAFF-11™. The high mRNA of early osteogenic gene expression and mineral deposits observed after hDPSCs osteogenesis on a PLCL mat indicated its better impact on hDPSCs’ osteogenic potential than that of HYAFF-11™, and hDPSC/PLCL constructs might be considered in the future as an innovative approach to bone defect repair.

IWP-2 modulates the immunomodulatory properties of human dental pulp stem cells invitro.

To investigate the effect of IWP-2, Wnt inhibitor, on human dental pulp stem cells (hDPSCs) responses. hDPSCs were isolated from human dental pulp tissues. Cells were treated with 25 μM IWP-2 for 24 h, and subsequently, the gene expression profile was examined using high-throughput RNA sequencing. The mRNA expression was analysed using qPCR. The effect of IWP-2 was investigated in both normal and LPS-induced hDPSCs (inflamed hDPSCs). CD4+ T cells and CD14+ monocyte-derived macrophages were cultured with conditioned media of IWP-2 treated hDPSCs to observe the immunosuppressive property. RNA sequencing indicated that IWP-2 significantly downregulated several KEGG pathways, including cytokine-cytokine receptor interaction, IL-17 signalling pathway, and TNF signalling pathway. In both normal and inflamed conditions, IWP-2 markedly upregulated TGFB1 mRNA expression while the mRNA expression of pro-inflammatory cytokines, TNFA, IL1B, IFNG, and IL6, was inhibited. In the inhibition experiment, the pretreatment with p38, MAPK, or PI3K inhibitors abolished the effects of IWP-2 in LPS-induced inflammation. In terms of immune cells, IWP-2-treated-inflamed hDPSCs conditioned media attenuated T cell proliferation and regulated regulatory T cell differentiation. In addition, the migratory property of macrophage was decreased after being exposed to IWP-2-treated inflamed hDPSCs conditioned media. IWP-2 suppressed inflammatory cytokine expression in both normal and inflamed hDPSCs. Moreover, hDPSCs exerted the immunosuppressive property after IWP-2 treatment. These results suggest the role of Wnt in inflammatory responses and immunomodulation in dental pulp tissues.

Human dental pulp stem cells have comparable abilities to umbilical cord mesenchymal stem/stromal cells in regulating inflammation and ameliorating hepatic fibrosis.

Hepatic fibrosis, also called cirrhosis, have wide prevalence worldwide for long yeas. Recently, many treatments for liver cirrhosis made marked progress, especially the umbilical cord-derived mesenchymal stromal cells (UCMSC) therapy. However, limited recourses and potential immune-related issues become the obstacles on UCMSC popularization in clinic. Therefore, we took dental pulp stem cells (DPSCs) into the consideration, since autologous DPSCs can be easily obtained without any ethnic or immune-related issues that heterogenous UCMSCs could encounter. We systematically compared the effects of both cell types and found that DPSCs had similar results to UCMSCs in regulating inflammation and reversing hepatic fibrosis. In our study, co-culturing T cells and PBMSCs showed that DPSCs have the ability to inhibit the proliferation of inflammatory cells and downregulate relevant inflammatory factors. In vitro and in vivo sterility tests confirmed the bio-safety of DPSCs. Moreover, the 1year-aged mouse model demonstrated that DPSCs successfully reversed hepatic fibrosis. Overall, DPSCs demonstrated comparable effectiveness to UCMSCs in regulating inflammation and reversing hepatic fibrosis, particularly in the aged mouse model that represents middle-aged and elderly humans. Since autologous DPSCs avoid potential immune-related issues that heterogenous UCMSCs could encounter, they may be a better choice for stem cell-related therapies.

Chitin scaffolds derived from the marine demosponge Aplysina fistularis stimulate the differentiation of dental pulp stem cells.

The use of stem cells for tissue regeneration is a prominent trend in regenerative medicine and tissue engineering. In particular, dental pulp stem cells (DPSCs) have garnered considerable attention. When exposed to specific conditions, DPSCs have the ability to differentiate into osteoblasts and odontoblasts. Scaffolds are critical for cell differentiation because they replicate the 3D microenvironment of the niche and enhance cell adhesion, migration, and differentiation. The purpose of this study is to present the biological responses of human DPSCs to a purified 3D chitin scaffold derived from the marine demosponge Aplysina fistularis and modified with hydroxyapatite (HAp). Responses examined included proliferation, adhesion, and differentiation. The control culture consisted of the human osteoblast cell line, hFOB 1.19. Electron microscopy was used to examine the ultrastructure of the cells (transmission electron microscopy) and the surface of the scaffold (scanning electron microscopy). Cell adhesion to the scaffolds was determined by neutral red and crystal violet staining methods. An alkaline phosphatase (ALP) assay was used for assessing osteoblast/odontoblast differentiation. We evaluated the expression of osteogenic marker genes by performing ddPCR for ALP, RUNX2, and SPP1 mRNA expression levels. The results show that the chitin biomaterial provides a favorable environment for DPSC and hFOB 1.19 cell adhesion and supports both cell proliferation and differentiation. The chitin scaffold, especially with HAp modification, isolated from A. fistularis can make a significant contribution to tissue engineering and regenerative medicine.

Nicotinamide Riboside Modulates HIF-1 Signaling to Maintain and Enhance Odontoblastic Differentiation in Human Dental Pulp Stem Cells.

Human dental pulp stem cells (hDPSCs) play a vital role in the regeneration of the pulp-dentin complex after pulp disease. While the regeneration efficiency relies on the odontoblastic differentiation capacity of hDPSCs, this is difficult to regulate within the pulp cavity. Although nicotinamide riboside (NR) has been found to promote tissue regeneration, its specific role in pulp-dentin complex regeneration is not fully understood. Here, we aimed to explore the role of NR in the odontoblastic differentiation of hDPSCs and its underlying molecular mechanism. It was found that NR enhanced the viability and retarded senescence in hDPSCs with higher NAD+/NADH levels. In contrast to the sustained action of NR, the multi-directional differentiation of hDPSCs was enhanced after NR pre-treatment. Moreover, in an ectopic pulp regeneration assay in nude mice, transplantation of hDPSCs pretreated with NR promoted the formation of a dentin-like structure surrounded by cells positively expressing DMP-1 and DSPP. RNA-Seq demonstrated inhibition of the HIF-1 signaling pathway in hDPSCs pretreated with NR. The number of HIF-1α-positive cells was significantly decreased in hDPSCs pretreated by NR in vivo. Similarly, NR significantly downregulated the expression of HIF-1α in vitro. The findings suggested that NR could potentially regulate hDPSC odontoblastic differentiation and promote the development of innovative strategies for dental pulp repair.

TyroFill-Titanium Implant Constructs for the Coordinated Repair of Rabbit Mandible and Tooth Defects.

Currently used methods to repair craniomaxillofacial (CMF) bone and tooth defects require a multi-staged surgical approach for bone repair followed by dental implant placement. Our previously published results demonstrated significant bioengineered bone formation using human dental pulp stem cell (hDPSC)-seeded tyrosine-derived polycarbonate scaffolds (E1001(1K)-bTCP). Here, we improved upon this approach using a modified TyroFill (E1001(1K)/dicalcium phosphate dihydrate (DCPD)) scaffold-supported titanium dental implant model for simultaneous bone-dental implant repair. TyroFill scaffolds containing an embedded titanium implant, with (n = 3 each time point) or without (n = 2 each time point) seeded hDPCs and Human Umbilical Vein Endothelial Cells (HUVECs), were cultured in vitro. Each implant was then implanted into a 10 mm full-thickness critical-sized defect prepared on a rabbit mandibulee. After 1 and 3 months, replicate constructs were harvested and analyzed using Micro-CT histological and IHC analyses. Our results showed significant new bone formation surrounding the titanium implants in cell-seeded TyroFill constructs. This study indicates the potential utility of hDPSC/HUVEC-seeded TyroFill scaffolds for coordinated CMF bone-dental implant repair.

Xanthium strumarium seed extract boosts osteogenesis in human dental pulp stem cell model

BackgroundIn traditional medicine, Xanthium strumarium is used as an anti-inflammatory and anti-arthritic plant-based medicine. Human Dental Pulp Stem Cells (hDPSCs) are an ideal in vitro model for drug and bioactive compound screening. This study assessed the potential of X. strumarium aqueous extract on hDPSCs differentiation towards the osteogenic lineage. Materials and methodsHDPSCs were isolated and cultured by explant method and characterized by surface marker expression, Colony Forming units fibroblasts (CFU-F), Population Doubling time (PDT), and tri-lineage differentiation. X. strumarium aqueous seed extract (XSE) was prepared and its cytotoxic effect on hDPSCs was examined by MTT assay. The effect of XSE on hDPSC differentiation into osteocytes was investigated by biochemical staining and gene expression. ResultsThe hDPSCs were positive for CD73, CD90, and CD105 and negative for CD34, CD45, and HLA-DR surface markers. The cells had a colony-forming ability with a PDT of 44.91 h. The hDPSCs differentiated into osteocytes, chondrocytes, and adipocytes. The XSE concentration of 15 μg/ml had a significant increase in hDPSC viability. Alizarin Red S staining revealed that XSE treatment enhanced calcium accumulation and matrix mineralization in hDPSCs. XSE treatment also increased osteonectin and IL-6 transcript expression in osteogenesis-induced hDPSCs. ConclusionX. strumarium aqueous extract is a suitable candidate for bone repair because it promotes osteogenic differentiation in hDPSCs. Therefore this could be explored further in the treatment of bone disorders.

Histological Evaluation of A unilateral Critical-Sized Mandibular Defect Reconstruction using human dental pulp stem cells by Light Microscope and Real-Time Quantitative PCR

Objective: To evaluate the osteogenic differentiation potential of human dental pulp stem cells (DPSCs) isolated from the dental pulp of third molar teeth in vitro cultures, and to evaluate the bone regenerative capacity of human dental pulp stem cells (DPSCs) when transplanted into a unilateral critical-sized bone defect in the mandibular bone in vivo after receiving a hydroxyapatite matrix and polylactic-polyglycolic acid (HA/PLGA) scaffold. Material and methods: A total of 18 mandibular defects were made, and three groups (each n = 6) were created. The first group: the transplanted DPSCs implanted in the critical-sized bone defect after receiving (HA/PLGA) scaffold. The second group received only (HA/PLGA) scaffold. The third group, which served as the control, had a critical-sized defect left empty. After characterization, Von Kossa [VK] and Alizarin red staining were employed to identify differentiated osteoblasts at the 14th and 21st days, and histological analyses, as well as polymerase chain reactions (PCR), were also used. Results: It showed that DPSCs had high proliferation potential and typical fibroblastic shape. Additionally, osteogenic differentiation of DPSCs was validated by morphological alterations, histological examination, and the expression of lineage-specific genes confirmed osteogenic differentiation of DPSCs. Conclusion: High proliferation potential and the capacity to differentiate into osteoblasts are two characteristics of DPSCs taken from impacted third molars.

Effect of Low-Level Laser Therapy on Differentiation and Proliferation of Human Dental Pulp Stem Cells: A Systematic Review.

Introduction: Considering the positive impact of laser treatment on the proliferation of certain cell types, we opted to perform a systematic review aimed at evaluating the effects of laser therapy and photobiomodulation on the proliferation and differentiation of human dental pulp stem cells (hDPSCs). Methods: We included all research studies examining the impact of laser therapy on hDPSCs, without limitations on publication dates or article languages. The major international databases, including PubMed, ISI Web of Science, and Scopus, were searched from inception to April 2022 by the relevant keywords. Results: In total, 1886 studies were identified in the initial search from the mentioned databases and other sources. Finally, 17 relevant studies were included in the present systematic review after removing duplicates and non-relevant articles. The results indicated the useful effect of low-level laser therapy (LLLT) on the hDPSCs. Conclusion: The findings of this systematic review indicate the useful role of LLLT in cell therapy, proliferation, and differentiation associated with hDPSCs.

Platelet-Rich Fibrin-Conditioned Medium as an Alternative to Fetal Bovine Serum Promotes Osteogenesis of Human Dental Pulp Stem Cells.

Human dental pulp stem cells (DPSCs) exhibit multilineage differentiation capabilities and superior clonogenic and proliferative properties. However, the use of animal-derived components such as FBS raises concerns regarding the clinical application of stem-cell-based therapies. Platelet-rich fibrin (PRF) derived from human blood is rich in fibrin, platelets, and growth factors and acts as a bioactive scaffold for grafting with biomaterials. In this study, we assessed the efficacy of PRF-conditioned medium (CM) in promoting DPSCs proliferation and osteogenic differentiation compared with the standard culture medium supplemented with FBS. A comparison of DPSCs cultured in FBS and PRF-CM revealed no differences in characteristics or morphology. However, cells cultured with PRF-CM exhibited inferior proliferation rates and cell numbers during passage in comparison with those cultured with FBS. In contrast, DPSCs cultured in PRF-CM showed significantly higher levels of calcification, and RT-PCR confirmed that the gene expression levels of markers associated with osteoblast differentiation were significantly increased. The PRF-CM approach offers a convenient, straightforward, and advantageous method for culturing DPSCs, without relying on animal-derived components. In summary, this study introduces a novel application of PRF-CM for enhancing the osteogenesis of DPSCs, which provides an alternative to FBS culture medium and addresses concerns associated with the use of animal-derived components in clinical settings.

The ATF4-regulated LncRNA MALAT1 promotes odontoblastic differentiation of human dental pulp stem cells via histone demethylase JMJD3: An in vitro study.

This study aimed to investigate the upstream regulators and specific mechanisms of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in the odontoblastic differentiation of human dental pulp stem cells (hDPSCs). Human dental pulp stem cells were isolated and cultured, followed by conducting loss- or gain-of-function experiments on ATF4 and loss experiments on MALAT1 to elucidate their respective biological functions in odontoblastic differentiation. Chromatin immunoprecipitation assays and RNA immunoprecipitation were performed to uncover the interaction between ATF4-MALAT1 and MALAT1-JMJD3, respectively. The odontoblastic differentiation was estimated by the mRNA and protein of DSPP and DMP1, as well as alkaline phosphatase staining. Expression of MALAT1 was upregulated in the hDPSCs cultured in an odontoblastic medium, and MALAT1 downregulation suppressed the odontoblastic differentiation of the hDPSCs. Subsequent experiments confirmed that ATF4 promoted odontoblastic differentiation and induced MALAT1 expression by binding to the MALAT1 promoter region. Further experiments revealed that nuclear MALAT1 interacted with JMJD3. MALAT1 knockdown decreased the JMJD3 protein level and demethylase activity, and it enhanced H3K27me3 occupancy of the promoter region of DSPP and DMP1, resulting in the inhibition of DSPP and DMP1 transcription. Importantly, JMJD3 overexpression significantly attenuated the inhibition of odontoblastic differentiation induced by MALAT1 knockdown. ATF4-regulated MALAT1 plays a positive regulatory role in odontoblastic differentiation of hDPSCs through JMJD3-mediated H3K27me3 modifications of the DSPP and DMP1 promoters.

FGFR1 variants contributed to families with tooth agenesis

BackgroundTooth agenesis is a common dental anomaly that can substantially affect both the ability to chew and the esthetic appearance of patients. This study aims to identify possible genetic factors that underlie various forms of tooth agenesis and to investigate the possible molecular mechanisms through which human dental pulp stem cells may play a role in this condition.ResultsUsing whole-exome sequencing of a Han Chinese family with non-syndromic tooth agenesis, a rare mutation in FGFR1 (NM_001174063.2: c.103G > A, p.Gly35Arg) was identified as causative and confirmed by Sanger sequencing. Via GeneMatcher, another family with a known variant (NM_001174063.2: c.1859G > A, p.Arg620Gln) was identified and diagnosed with tooth agenesis and a rare genetic disorder with considerable intrafamilial variability. Fgfr1 is enriched in the ectoderm during early embryonic development of mice and showed sustained low expression during normal embryonic development of Xenopus laevis frogs. Functional studies of the highly conserved missense variant c.103G > A showed deleterious effects. FGFR1 (c.103G > A) was overexpressed compared to wildtype and promoted proliferation while inhibiting apoptosis in HEK293 and human dental pulp stem cells. Moreover, the c.103G > A variant was found to suppress the epithelial-mesenchymal transition. The variant could downregulate ID4 expression and deactivate the TGF-beta signaling pathway by promoting the expression of SMAD6 and SMAD7.ConclusionOur research broadens the mutation spectrum associated with tooth agenesis and enhances understanding of the underlying disease mechanisms of this condition.

Low, medium, and high molecular weight hyaluronic acid effects on human dental pulp stem cells in vitro

Hyaluronic acid (HA), an extracellular biopolymer found throughout the human body, holds promise as a biocompatible and biodegradable scaffold material. High molecular weight (HMW) HA degrades, generating low molecular weight (LMW) fragments with distinct properties. These fragments can influence the behaviour of cells, including human dental pulp stem cells (hDPSCs) incorporated into HA-containing hydrogels or scaffolds. Therefore, a comprehensive examination of the impact of a range of HA molecular weights on hDPSCs is essential before designing HA-based scaffolds for these cells. hDPSC lines were cultured with LMW HA (800 Da, 1600 Da, 15 kDa), medium molecular weight HA (237 kDa), or HMW HA (1500 kDa) over six passages. The various molecular weights had negligible effects on hDPSCs viability, morphology, adhesion, or relative telomere length. Furthermore, the expression of key surface stemness markers (CD29, CD44, CD73, CD90) remained unaltered. HA did not induce osteogenic, chondrogenic, or adipogenic differentiation. Moreover, the potential for chondrogenic and osteogenic differentiation was not adversely affected by LMW or HMW HA. Various molecular weights of HA seem safe, biocompatible and therefore suitable components for hDPSCs-containing scaffolds. These findings affirm that the hDPCSs will not be negatively affected by HA fragments resulting from scaffold degradation.

Chemoselective Coatings of GL13K Antimicrobial Peptides for Dental Implants.

Dental implant-associated infection is a clinical challenge which poses a significant healthcare and socio-economic burden. To overcome this issue, developing antimicrobial surfaces, including antimicrobial peptide coatings, has gained great attention. Different physical and chemical routes have been used to obtain these biofunctional coatings, which in turn might have a direct influence on their bioactivity and functionality. In this study, we present a silane-based, fast, and efficient chemoselective conjugation of antimicrobial peptides (Cys-GL13K) to coat titanium implant surfaces. Comprehensive surface analysis was performed to confirm the surface functionalization of as-prepared and mechanically challenged coatings. The antibacterial potency of the evaluated surfaces was confirmed against both Streptococcus gordonii and Streptococcus mutans, the primary colonizers and pathogens of dental surfaces, as demonstrated by reduced bacteria viability. Additionally, human dental pulp stem cells demonstrated long-term viability when cultured on Cys-GL13K-grafted titanium surfaces. Cell functionality and antimicrobial capability against multi-species need to be studied further; however, our results confirmed that the proposed chemistry for chemoselective peptide anchoring is a valid alternative to traditional site-unspecific anchoring methods and offers opportunities to modify varying biomaterial surfaces to form potent bioactive coatings with multiple functionalities to prevent infection.

Potent antitumor efficacy of human dental pulp stem cells armed with YSCH-01 oncolytic adenovirus

BackgroundSystemic administration of oncolytic adenovirus for cancer therapy is still a challenge. Mesenchymal stem cells as cell carriers have gained increasing attention in drug delivery due to their excellent tumor tropism, immunosuppressive modulatory effects, and paracrine effects. However, the potential of human dental pulp stem cells (hDPSCs) loaded with oncolytic adenovirus for cancer biotherapy has not been investigated yet.MethodsThe stemness of hDPSCs was characterized by FACS analysis and Alizarin red staining, Oil Red O staining, and immunofluorescence assays. The biological fitness of hDPSCs loaded with oncolytic adenovirus YSCH-01 was confirmed by virus infection with different dosages and cell viability CCK-8 assays. Additionally, the expression of CAR receptor in hDPSCs was detected by qPCR assay. Tumor tropism of hDPSC loaded with YSCH-01 in vitro and in vivo was investigated by Transwell assays and living tumor-bearing mice imaging technology and immunohistochemistry, Panoramic scanning of frozen section slices assay analysis. Furthermore, the antitumor efficacy was observed through the different routes of YSCH-01/hPDSCs administration in SW780 and SCC152 xenograft models. The direct tumor cell-killing effect of YSCH-01/hDPSCs in the co-culture system was studied, and the supernatant of YSCH-01/hDPSCs inhibited cell growth was further analyzed by CCK-8 assays.ResultshDPSCs were found to be susceptible to infection by a novel oncolytic adenovirus named YSCH-01 and were capable of transporting this virus to tumor sites at 1000 VP/cell infectious dosage in vitro and in vivo. Moreover, it was discovered that intraperitoneal injection of hDPSCs loaded with oncolytic adenovirus YSCH-01 exhibited potential anti-tumor effects in both SW780 and SCC152 xenograft models. The crucial role played by the supernatant secretome derived from hDPSCs loaded with YSCH-01 significantly exerted a specific anti-tumor effect without toxicity for normal cells, in both an active oncolytic virus and an exogenous protein-independent manner. Furthermore, the use of hDPSCs as a cell carrier significantly reduced the required dosage of virus delivery in vivo compared to other methods.ConclusionsThese findings highlight the promising clinical potential of hDPSCs as a novel cell carrier in the field of oncolytic virus-based anti-cancer therapy.