Human Stem Research Articles

Biocompatibility, bioactivity and immunomodulatory properties of three calcium silicate-based sealers: an in vitro study on hPDLSCs

ObjectivesTo assess the biocompatibility, bioactivity, and immunomodulatory properties of three new calcium silicate cement-based sealers: Ceraseal (CS), Totalfill BC Sealer (TFbc) and WellRoot ST (WR-ST) on human periodontal ligament stem cells (hPDLSCs).Materials and methodsHPDLSCs were isolated from extracted third molars from healthy patients. Eluates (1:1, 1:2, and 1:4 ratio) and sample discs of CS, TFbc and WR-ST after setting were prepared. A series of assays were performed: cell characterization, cell metabolic activity (MTT assay) cell attachment and morphology (SEM assay), cell migration (wound-healing assay), cytoskeleton organization (phaloidin-based assay); IL-6 and IL-8 release (ELISA); differentiation marker expression (RT-qPCR assay), and cell mineralization (Alizarin Red S staining). HPDLSCs cultured in unconditioned (negative control) or osteogenic (positive control) culture media were used as a comparison. Statistical significance was established at p < 0.05.ResultsAll the tested sealers exhibited similar results in the cytocompatibility assays (cell metabolic activity, migration, attachment, morphology, and cytoskeleton organization) compared with a negative control group. CS and TFbc exhibited an upregulation of at least one osteo/cementogenic marker compared to the negative and positive control groups. CS and TFbc also showed a significantly higher calcified nodule formation than the negative and positive control groups. Both the marker expression and calcified nodule formation were significantly higher in CS-treated cells than TFbc treated cells. WR-ST exhibited similar results to the control group. CS and TFbc-treated cells exhibited a significant downregulation of IL-6 after 72 h of culture compared to the negative control group (p < 0.05).ConclusionAll the tested sealers exhibited an adequate cytocompatibility. CS significantly enhances cell differentiation by upregulating the expression of key genes associated with bone and cementum formation. Additionally, CS was observed to facilitate the mineralization of the extracellular matrix effectively. In contrast, the effects of TFbc and WR-ST on these processes were less pronounced compared to CS. Furthermore, both CS and TFbc exhibited an anti-inflammatory potential, contributing to their potential therapeutic benefits in regenerative endodontics.Clinical relevanceThis is the first study to compare the biological properties and immunomodulatory potential of Ceraseal, Totalfill BC Sealer, and WellRoot ST. The results act as supporting evidence for their use in root canal treatment.

Inhibition of mast cell degranulation by novel small molecule MRGPRX2 antagonists

BackgroundMas-related G-protein coupled receptor X2 (MRGPRX2) is a promiscuous receptor on mast cells that mediates IgE-independent degranulation and has been implicated in multiple mast cell-mediated disorders, including chronic urticaria, atopic dermatitis, and pain disorders. Although it is a promising therapeutic target, few potent, selective, small molecule antagonists have been identified, and functional effects of human MRGPRX2 inhibition have not been evaluated in vivo. ObjectiveWe identified and characterized novel, potent, and selective orally active small molecule MRGPRX2 antagonists for potential treatment of mast cell-mediated disease. MethodsAntagonists were identified using multiple functional assays in cell lines overexpressing human MRGPRX2, LAD2 mast cells, human peripheral stem cell-derived mast cells, and isolated skin mast cells. Skin mast cell degranulation was evaluated in Mrgprb2em(-/-) knockout (KO) and Mrgprb2em(MRGPRX2) transgenic human MRGPRX2 knock-in (KI) mice by assessment of agonist-induced skin vascular permeability. Ex vivo skin mast cell degranulation and associated histamine release was evaluated by microdialysis of human skin tissue samples. ResultsMRGPRX2 antagonists potently inhibited agonist-induced MRGPRX2 activation and mast cell degranulation in all mast cell types tested, in an IgE-independent manner. Orally administered MRGPRX2 antagonists also inhibited agonist-induced degranulation and resulting vascular permeability in MRGPRX2 KI mice. In addition, antagonist treatment dose dependently inhibited agonist-induced degranulation in ex vivo human skin. ConclusionMRGPRX2 small molecule antagonists potently inhibited agonist-induced mast cell degranulation in vitro and in vivo as well as ex vivo in human skin, supporting potential therapeutic utility as a novel treatment for multiple human diseases involving clinically relevant mast cell activation.

Restoration of T and B Cell Differentiation after RAG1 Gene Transfer in Human RAG1 Defective Hematopoietic Stem Cells.

Recombinase-activating gene (RAG)-deficient SCID patients lack B and T lymphocytes due to the inability to rearrange immunoglobulin and T cell receptor genes. The two RAG genes act as a required dimer to initiate gene recombination. Gene therapy is a valid treatment alternative for RAG-SCID patients who lack a suitable bone marrow donor, but developing such therapy for RAG1/2 has proven challenging. Using a clinically approved lentiviral vector with a codon-optimized RAG1 gene, we report here preclinical studies using CD34+ cells from four RAG1-SCID patients. We used in vitro T cell developmental assays and in vivo assays in xenografted NSG mice. The RAG1-SCID patient CD34+ cells transduced with the RAG1 vector and transplanted into NSG mice led to restored human B and T cell development. Together with favorable safety data on integration sites, these results substantiate an ongoing phase I/II clinical trial for RAG1-SCID.

Human Neural Stem Cell Expansion in Natural Polymer Scaffolds Under Chemically Defined Condition.

The maintenance and expansion of human neural stem cells (hNSCs) in 3D tissue scaffolds is a promising strategy in producing cost-effective hNSCs with quality and quantity applicable for clinical applications. A few biopolymers have been extensively used to fabricate 3D scaffolds, including hyaluronic acid, collagen, alginate, and chitosan, due to their bioactive nature and availability. However, these polymers are usually applied in combination with other biomolecules, leading to their responses difficult to ascribe to. Here, scaffolds made of chitosan, alginate, hyaluronic acid, or collagen, are explored for hNSC expansion under xeno-free and chemically defined conditions and compared for hNSC multipotency maintenance. This study shows that the scaffolds made of pure chitosan support the highest adhesion and growth of hNSCs, yielding the most viable cells with NSC marker protein expression. In contrast, the presence of alginate, hyaluronic acid, or collagen induces differentiation toward immature neurons and astrocytes even in the maintenance medium and absence of differentiation factors. The cells in pure chitosan scaffolds preserve the level of transmembrane protein profile similar to that of standard culture. These findings point to the potential of using pure chitosan scaffolds as a base scaffolding material for hNSC expansion in 3D.

Exosomes derived from Polygonum multiflorum-treated human dental pulp stem cells (hDPSCs): New approach in regenerative medicine

Extracellular vesicles (EVs) are currently being extensively utilized in clinical trials. Our previous study demonstrated that the conditioned medium of human dental pulp stem cells (hDPSCs) treated by 2,3,5,4′-tetrahydroxystilbene-2-O-β-D-glucoside (THSG) exhibits biological activity and anti-inflammatory responses, which are believed to be regulated by EVs. To date, no study has thoroughly investigated the potential of the exosomes released by THSG-treated hDPSCs. In this study, we utilized the conditioned medium (CM) of hDPSCs with/without THSG stimulation to compare the differences in exosome extraction using ultracentrifugation (UC), tangential flow filtration (TFF), and TFF combined with size-exclusion chromatography (TFF + SEC) methods, aiming to establish an effective purification method. Subsequently, we analyzed the contents of the exosomes using proteomic strategy. The results showed that TFF + SEC was more effective in reducing protein contamination compared to CM and TFF alone. TFF effectively concentrated large-scale CM and maintained exosome particle sizes consistently around 85–100 nm. Flow cytometry analysis revealed that the presence of THSG increased exosome secretion from hDPSCs, concurrently leading to the identification of 219 unique proteins through proteomic analysis, including BMP-1, VEGF, and members of the MMP family. Compared to non-lyophilized exosomes, lyophilized exosomes showed no change in protein activity, indicating that lyophilization was an effective preservation method. Collectively, these findings present a combined extraction strategy for dental stem cell exosomes and reveal the high purity and proteome composition of THSG-exosomes, thereby highlighting their potential applications in regenerative therapy.

Amorphous titanium oxide (aTiO2) thin films biofunctionalized with CAP-p15 induce mineralized-like differentiation of human oral mucosal stem cells (hOMSCs)

Insufficient osseointegration of titanium-based implants is a factor conditioning their long-term success. Therefore, different surface modifications, such as multifunctional oxide coatings, calcium phosphates, and the addition of molecules such as peptides, have been developed to improve the bioactivity of titanium-based biomaterials. In this work, we investigate the behavior of human oral mucosal stem cells (hOMSCs) cultured on amorphous titanium oxide (aTiO2), surfaces designed to simulate titanium (Ti) surfaces, biofunctionalized with a novel sequence derived from cementum attachment protein (CAP-p15), exploring its impact on guiding hOMSCs towards an osteogenic phenotype. We carried out cell attachment and viability assays. Next, hOMSCs differentiation was assessed by red alizarin stain, ALP activity, and western blot analysis by evaluating the expression of RUNX2, BSP, BMP2, and OCN at the protein level. Our results showed that functionalized surfaces with CAP-p15 (1 µg ml−1) displayed a synergistic effect increasing cell proliferation and cell attachment, ALP activity, and expression of osteogenic-related markers. These data demonstrate that CAP-p15 and its interaction with aTiO2 surfaces promote osteoblastic differentiation and enhanced mineralization of hOMSCs when compared to pristine samples. Therefore, CAP-p15 shows the potential to be used as a therapeutical molecule capable of inducing mineralized tissue regeneration onto titanium-based implants.

MiR-708-3p targetedly regulates LSD1 to promote osteoblast differentiation of hPDLSCs in periodontitis.

Periodontitis (PD) is a multifactorial inflammatory disease associated with periodontopathic bacteria. Lysine-specific demethylase 1 (LSD1), a type of histone demethylase, has been implicated in the modulation of the inflammatory response process in oral diseases by binding to miRNA targets. This study investigates the molecular mechanisms by which miRNA binds to LSD1 and its subsequent effect on osteogenic differentiation. First, human periodontal ligament stem cells (hPDLSCs) were isolated, cultured, and characterized. These cells were then subjected to lipopolysaccharide (LPS) treatment to induce inflammation, after which osteogenic differentiation was initiated. qPCR and western blot were employed to monitor changes in LSD1 expression. Subsequently, LSD1 was silenced in hPDLSCs to evaluate its impact on osteogenic differentiation. Through bioinformatics and dual luciferase reporter assay, miR-708-3p was predicted and confirmed as a target miRNA of LSD1. Subsequently, miR-708-3p expression was assessed, and its role in hPDLSCs in PD was evaluated through overexpression. Using chromatin immunoprecipitation (ChIP) and western blot assay, we explored the potential regulation of osterix (OSX) transcription by miR-708-3p and LSD1 via di-methylated H3K4 (H3K4me2). Finally, we investigated the role of OSX in hPDLSCs. Following LPS treatment of hPDLSCs, the expression of LSD1 increased, but this trend was reversed upon the induction of osteogenic differentiation. Silencing LSD1 strengthened the osteogenic differentiation of hPDLSCs. miR-708-3p was found to directly bind to and negatively regulate LSD1, leading to the repression of OSX transcription through demethylation of H3K4me2. Moreover, overexpression of miR-708-3p was found to promote hPDLSCs osteogenic differentiation in inflammatory microenvironment. However, the protective effect was partially attenuated by reduced expression of OSX. Our findings indicate that miR-708-3p targetedly regulates LSD1 to enhance OSX transcription via H3K4me2 methylation, ultimately promoting hPDLSCs osteogenic differentiation.

O-132 A systematic spatial HiPlex proteomics exploration of human testicular tissues from birth to adulthood

Abstract Study question Can we map the key maturation stages of human spermatogonial stem cells (SSCs) within their niche during infancy and puberty? Summary answer Using highplex spatial proteomics, we describe the key cellular events taking place during human testis maturation. What is known already The human testis is a complex “ecosystem” that matures in response to endocrine and exocrine signals and interactions between its diverse cellular components. Unlike animal models, in humans, testicular maturation is a slow process that takes place over more than a decade. In contrast to ovaries, the human testis retains its immature state until the onset of puberty. Single-cell RNA sequencing data has revealed significant developmental changes for germ cell and the somatic niche during infancy and puberty. Study design, size, duration Using the hyperplex imaging technique (CellDIVE) and a panel of 30 protein markers - selected to label key components of the developing human testis - we have systematically analyzed a time series of ∼75 testicular biopsies from boys aged 8 months to adulthood. Following sequential staining and capture of high-resolution images, our analysis pipeline involves the conversion of image into single-cell data, which allows a systematic description of the spatial SSC/niche microenvironment interactions across development. Participants/materials, setting, methods The panel of antibody markers was defined using integrated scRNAseq data and represents all key cell types, including germ cell markers (e.g., MAGEA4), Sertoli cell markers (e.g., SOX9), Leydig cell markers (e.g., INSL3), myoid cell markers (e.g., ACTA2) ... Main results and the role of chance To describe the events occurring during human testicular maturation, we build a Tissue Microarray (TMA) containing ∼75 biopsies of boys of different ages (0-16yrs old) and using an in-house panel of 30 markers for high-dimensional multiplex CELL DIVE images. Our analytical strategy uses Uniform Manifold Approximation and Projection (UMAP) maps to quantify and statistically compare single-cell data. Our marker panel allows us to phenotype testicular cells at different stages of development, including SSCs (state 0 to state 4), Sertoli cells, Leydig cells, and so on. Moreover, employing spatial-latent Dirichlet allocation (LDA), we identified recurrent cellular neighbourhoods (RCNs), revealing distinct cell clusters and their corresponding RCNs. These RCNs reflect recurring spatial arrangements of cells within testicular tissues, allowing us to infer the spatial organization and interplay among different cell types. Additionally, we explored spatial distances and neighbourhood frequencies across different tissues and conducted spatial co-occurrence analysis to assess the likelihood of finding adjacent cell types. The identification of RCNs offers valuable insights into the microenvironmental dynamics and cellular relationships taking place within the developing testis. Looking ahead, we aim to delve into the functional significance of RCNs in shaping the developmental trajectories and physiological processes within human testicular tissues. Limitations, reasons for caution Due to limitations in proteomics techniques, we could only include ∼30 protein markers on our panel. Although the biopsy samples used in our study are all from chemo-naïve patients, it possible that the conditions affecting these paediatric patients may impact the architecture or development of their testicular tissues. Wider implications of the findings Our study provides a systematic approach to study the development and organization of human testicular structures, which will allow to enumerate the cellular content of individual testicular biopsies and infer their stage of maturation, therefore providing a personalised baseline assessment for each patient at the time of cryopreservation. Trial registration number not applicable

P-800 Best matrix match: Laminin-511 improves human trophoblast stem cell identity in vitro

Abstract Study question Can alternative basement membranes support human trophoblast stem cell (hTSC) culture and recapitulate the in vivo environment more effectively than Collagen-IV (Col-IV)? Summary answer Laminin-511 (Lam-511) is the optimal alternative xeno-free matrix that enhances the stem cell state and more closely recapitulates the in vivo hTSC niche. What is known already Our knowledge on early placentation is limited due to a historical lack of robust in vitro models. Recently, hTSCs isolated from human blastocysts and first trimester placentas were successfully cultured on Col-IV, recapitulating cytotrophoblast cell self-renewal and differentiation. Even though Col-IV has been detected in the cytotrophoblast basement membrane, previously published RNA-seq analysis does not detect transcripts encoding Col-IV in the human trophectoderm. Attachment of adhesion molecules to the ECM can have an effect on cell proliferation, differentiation, polarity and gene expression. Using the correct matrix ensures a stable cell growth, as it can influence cell behaviour and identity. Study design, size, duration This was a prospective study carried out over a 6-month period. Patient-derived hTSC lines, BTS5 and CT27, obtained from RIKEN BRC Cell Bank were cultured according to the previously published protocol (1). hTSCs were maintained on culture plates coated with Col-IV, Lam-511, laminin-521 and fibronectin. Experiments were performed with biological replicates of both cell lines (n = 4), grown in every condition. Cells grown on Col-IV were used as a positive control. Participants/materials, setting, methods hTSCs were maintained on the candidate matrices for minimum of 5 passages and then were used for subsequent experiments. hTSC identity was determined by immunofluorescence analysis for known hTSC markers, GATA2 and KRT18. qRT-PCR analyses were also performed to detect additional markers EGFR, ITGA6, TEAD4, TP63, and expression from the chromosome 19 miRNA cluster (C19MC). The self-renewal capacity was assessed by cell counting and Ki67-staining. The differentiation potential was examined by performing previously published protocols. Main results and the role of chance RNA-seq analysis identified expression of ECM ligand and receptor transcripts encoding Lam-511, laminin-521 and fibronectin, which were used as candidate matrices to test. hTSC identity was maintained in all conditions as confirmed by morphological assessment, expression of known hTSC markers at the transcript and protein level, and detection of expression of C19MC miRNAs. The highest hTSC marker expression was found in cells grown on laminins. However, interestingly it was observed that only Lam-511 was capable of supporting hTSCs for more than 15 passages. Compared to Col-IV, hTSCs grown on Lam-511 appear to be more proliferative as there was a higher cell count over a 6-day period and a higher proportion of Ki-67-positive proliferative cells (p = 0.03). Additionally, preliminary data suggests that differentiation ability of hTSCs grown on Lam-511 into syncytiotrophoblasts and extravillous cytotrophoblasts is retained. Therefore, Lam-511 is an improvement to the conventional model as it enhances the stem-cell identity and closely recapitulates the in vivo niche. It can also be used as an alternative xeno-free matrix in hTSC culture in order to overcome current supply chain issues and reduce batch-to-bath variability associated with Col-IV. Limitations, reasons for caution During the 6-month period of this study, two contaminations occurred that led to slower progression of the experiments and smaller sample size. Also, there was low efficiency of the extravillous cytotrophoblast differentiation which was due to the fact that the previously published protocol performed has not yet been optimised. Wider implications of the findings Recapitulating the in vivo niche more closely will allow a deeper understanding of early placentation and help create more accurate 3D models to study the pathomechanisms of various pregnancy complications. Furthermore, utilising the xeno-free Lam-511 as an alternative matrix is a step closer to building a GMP-compliant hTSC culture. Trial registration number Not applicable

Decoding human bone marrow hematopoietic stem and progenitor cells from fetal to birth

Bone marrow (BM) is the dominant site of hematopoiesis after 20 post-conception weeks (PCWs), but the intricacies of hematopoietic development in fetal BM up to birth and its involvement in malignancies remain unknown. Here, we compared the single-cell transcriptomic profile of BM hematopoietic stem and progenitor cells (HSPCs) at the early (12-14 PCW), middle (19-22 PCW) second trimester, and the neonatal stage. The stemness of hematopoietic stem cell and multipotent progenitor (HSC/MPP) is established at the middle second trimester, then maintained until birth. Furthermore, differentiation potentials toward three lineages are enhanced after the middle second trimester for birth, accompanied by the upregulation of aerobic metabolism. Notably, decreased stemness in HSCs/MPPs and higher interferon signals in progenitors at the early second trimester rendered the HSPCs more proximal to leukemogenesis. Collectively, our work elucidated the dynamics of fetal hematopoiesis in preparation for birth, offering valuable insights into the pathological processes underlying leukemia.

Inhibition of PHLDA3 expression in human superoxide dismutase 1-mutant amyotrophic lateral sclerosis astrocytes protects against neurotoxicity.

Pleckstrin homology-like domain family A-member 3 (PHLDA3) has recently been identified as a player in adaptive and maladaptive cellular stress pathways. The outcome of pleckstrin homology-like domain family A-member 3 signalling was shown to vary across different cell types and states. It emerges that its expression and protein level are highly increased in amyotrophic lateral sclerosis (ALS) patient-derived astrocytes. Whether it orchestrates a supportive or detrimental function remains unexplored in the context of neurodegenerative pathologies. To directly address the role of pleckstrin homology-like domain family A-member 3 in healthy and ALS astrocytes, we used overexpression and knockdown strategies. We generated cultures of primary mouse astrocytes and also human astrocytes from control and ALS patient-derived induced pluripotent stem cells harbouring the superoxide dismutase 1 mutation. Then, we assessed astrocyte viability and the impact of their secretome on oxidative stress responses in human stem cell-derived cortical and spinal neuronal cultures. Here, we show that PHLDA3 overexpression or knockdown in control astrocytes does not significantly affect astrocyte viability or reactive oxygen species production. However, PHLDA3 knockdown in ALS astrocytes diminishes reactive oxygen species concentrations in their supernatants, indicating that pleckstrin homology-like domain family A-member 3 can facilitate stress responses in cells with altered homeostasis. In support, supernatants of PHLDA3-silenced ALS and even control spinal astrocytes with a lower pleckstrin homology-like domain family A-member 3 protein content could prevent sodium arsenite-induced stress granule formation in spinal neurons. Our findings provide evidence that reducing pleckstrin homology-like domain family A-member 3 levels may transform astrocytes into a more neurosupportive state relevant to targeting non-cell autonomous ALS pathology.

Exosomal lncRNA HCP5 derived from human bone marrow mesenchymal stem cells improves chronic periodontitis by miR-24-3p/HO1/P38/ELK1 pathway

ObjectiveThe present study aimed to explore the function of human bone marrow mesenchymal stem cells (hBMMSCs)-derived exosomal long noncoding RNA histocompatibility leukocyte antigen complex P5 (HCP5) in the osteogenic differentiation of human periodontal ligament stem cells (hPDLSCs) to improve chronic periodontitis (CP). MethodsExosomes were extracted from hBMMSCs. Alizarin red S staining was used to detect mineralised nodules. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure HCP5 and miR-24-3p expression. The mRNA and protein levels of alkaline phosphatase (ALP), osteocalcin, osterix, runt-related transcription factor 2, bone morphogenetic protein 2, osteopontin, fibronectin, collagen 1, heme oxygenase 1 (HO1), P38, and ETS transcription factor ELK1 (ELK1) were detected using RT-qPCR and Western blot. Enzyme-linked immunosorbent assay (ELISA) kits were used to determine the HO1 and carbon monoxide concentrations. Heme, biliverdin, and Fe2+ levels were determined using detection kits. Micro-computed tomography, hematoxylin and eosin staining, ALP staining, tartrate-resistant acid phosphatase staining, ELISA, and RT-qPCR were conducted to evaluate the effect of HCP5 on CP mice. Dual luciferase, RNA immunoprecipitation, and RNA pulldown experiments were performed to identify the interactions among HCP5, miR-24-3p, and HO1. ResultsThe osteogenic ability of hPDLSCs significantly increased when co-cultured with hBMMSCs or hBMMSCs exosomes. Overexpression of HCP5 and HO1 in hBMMSCs exosomes promoted the osteogenic differentiation of hPDLSCs, and knockdown of HCP5 repressed the osteogenic differentiation of hPDLSCs. HCP5 knockdown enhanced the inflammatory response and repressed osteogenesis in CP mice. MiR-24-3p overexpression diminished the stimulatory effect of HCP5 on the osteogenic ability of hPDLSCs. Mechanistically, HCP5 acted as a sponge for miR-24-3p and regulated HO1 expression, and HO1 activated the P38/ELK1 pathway. ConclusionHBMMSCs-derived exosomal HCP5 promotes the osteogenic differentiation of hPDLSCs and alleviates CP by regulating the miR-24-3p/HO1/P38/ELK1 signalling pathway.

Amniotic miracle: Investigating the unique development and applications of amniotic membrane in wound healing.

The perfect repair of damaged skin has always been a constant goal for scientists; however, the repair and reconstruction of skin is still a major problem and challenge in injury and burns medicine. Human amniotic membrane (hAM), with its good mechanical properties and anti-inflammatory, antioxidant and antimicrobial benefits, containing growth factors that promote wound healing, has evolved over the last few decades from simple skin sheets to high-tech dressings, such as being made into nanocomposites, hydrogels, powders, and electrostatically spun scaffolds. This paper aims to explore the historical development, applications, trends, and research hotspots of hAM in wound healing. We examined 2660 publications indexed in the Web of Science Core Collection (WoSCC) from January 1, 1975 to July 12, 2023. Utilizing bibliometric methods, we employed VOSviewer, CiteSpace, and R-bibliometrix to characterize general information, identify development trends, and highlight research hotspots. Subsequently, we identified a collection of high-quality English articles focusing on the roles of human amniotic epithelial stem cells (hAESCs), human amniotic mesenchymal stem cells (hAMSCs), and amniotic membrane (AM) scaffolds in regenerative medicine and tissue engineering. Bibliometric analysis identified Udice-French Research Universities as the most productive affiliation and Tseng S.C.G. as the most prolific author. Keyword analysis, historical direct quotations network, and thematic analysis helped us review the historical and major themes in this field. Our examination included the knowledge structure, global status, trends, and research hotspots regarding the application of hAM in wound healing. Our findings indicate that contemporary research emphasizes the preparation and application of products derived from hAM. Notably, both hAM and the cells isolated from it - hADSCs and hAESCs are prominent and promising areas of research in regenerative medicine and tissue engineering. This research delivers a comprehensive understanding of the knowledge frameworks, global dynamics, emerging patterns, and primary research foci in the realm of hAM applications for wound healing. The field is rapidly evolving, and our findings offer valuable insights for researchers. Future research outcomes are anticipated to be applied in clinical practice, enhancing methods for disease prevention, diagnosis, and treatment.

New method to induce neurotrophin gene expression in human adipose-derived stem cells in vitro.

Rosemary leaf extract, a well-known medicinal plant, can induce neurotrophin gene expression and proliferation in stem cells. Human adipose-derived stem cells (hASCs) with high proliferation and differentiation capacity are easily accessible and can be extracted with the least damage. This study evaluated the effect of rosemary extract (RE) on neurotrophin gene expression at 48 h postinduction in hASCs. hASCs were isolated from healthy female donors, aged 28-35 years, who had undergone abdominal liposuction. Passage-4 stem cells were cultured and treated with different doses of RE (from 30 to 70 µg/ml) containing 40% carnosic acid for 48 h. Reverse transcription-polymerase chain reaction was used to check the expression of neurotrophin genes. The expression of NTF3, NTF4, and nerve growth factor genes in cells treated with 40-60 µg/ml and the expression of GDNF in cells treated with 50-70 µg/ml of RE for 48 h showed a significant increase compared to cells cultured in serum-containing medium. However, different doses of RE showed no effect on brain-derived neurotrophic factor gene expression in the treated cells. RE (50, 60 µg/ml) leads to an increase of neurotrophin gene expression in hASCs as compared to routine cell culture. Hence, this protocol can be used to prepare ideal cell sources for cell therapy.

Premixed calcium silicate-based ceramic sealers promote osteogenic/cementogenic differentiation of human periodontal ligament stem cells: A microscopy study.

To evaluate the effects of premixed calcium silicate based ceramic sealers on the viability and osteogenic/cementogenic differentiation of human periodontal ligament stem cells (hPDLSCs). The materials evaluated were TotalFill BC Sealer (TFbc), AH Plus Bioceramic Sealer (AHPbc), and Neosealer Flo (Neo). Standardized discs and 1:1, 1:2, and 1:4 eluates of the tested materials were prepared. The following in vitro experiments were carried out: ion release, cell metabolic activity 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell migration, immunofluorescence experiment, cell attachment, gene expression, and mineralization assay. Statistical analyses were performed using one-way ANOVA followed by Tukey's post hoc test (p < .05). Increased Ca2+ release was detected in TFbc compared to AHPbc and Neo (*p < .05). Biological assays showed a discrete cell metabolic activity and cell migration in Neo-treated cell, whereas scanning electronic microscopy assay exhibited that TFbc group had a better cell adhesion process of substrate attachment, spreading, and cytoskeleton development on the niche-like structures of the cement than AHPbc and Neo. The sealers tested were able to induce overexpression of the CEMP-1, ALP, and COL1A1 genes in the first days of exposure, particularly in the case of TFbc (***p < .001). All materials tested significantly increased the mineralization of hPDLSCs when compared to the negative control, although more pronounced calcium deposition was observed in the TFbc-treated cells (***p < .001). Our results suggested that TFbc promotes cell differentiation, both by increasing the expression of key osteo/odontogenic genes and by promoting mineralization of the extracellular matrix, whereas this phenomenon was less evident in Neo and AHPbc. RESEARCH HIGHLIGHTS: TFbc group had a better cell adhesion process of substrate attachment, spreading, and cytoskeleton development on the niche-like structures of the cement than AHPbc and Neo. The sealers tested were able to induce overexpression of the CEMP-1, ALP, and COL1A1 genes in the first days of exposure, particularly in the case of TFbc. All materials tested significantly increased the mineralization of hPDLSCs when compared to the negative control, although more pronounced calcium deposition was observed in the TFbc-treated cells.

Nicotine-induced Genetic and Epigenetic Modifications in Primary Human Amniotic Fluid Stem Cells.

Smoking during pregnancy has been linked to adverse health outcomes in offspring, but the underlying mechanisms are not fully understood. To date, the effect of maternal smoking has been tested in primary tissues and animal models, but the scarcity of human tissues limits experimental studies. Evidence regarding smoking-related molecular alteration and gene expression profiles in stem cells is still lacking. We developed a cell culture model of human amniotic fluid stem cells (hAFSCs) of nicotine (NIC) exposure to examine the impact of maternal smoking on epigenetic alterations of the fetus. NIC 0.1 μM(equivalent to "light" smoking, i.e., 5 cigarettes/day) did not significantly affect cell viability; however, significant alterations in DNA methylation and N6-methyladenosine (m6A) RNA methylation in hAFSCs occurred. These epigenetic changes may influence the gene expression and function of hAFSCs. Furthermore, NIC exposure caused time-dependent alterations of the expression of pluripotency genes and cell surface markers, suggesting enhanced cell stemness and impaired differentiation potential. Furthermore, NICtreated cells showed reduced mRNA levels of key adipogenic markers and hypomethylation of the promoter region of the imprinted gene H19 during adipogenic differentiation, potentially suppressing adipo/lipogenesis. Differential expression of 16 miRNAs, with predicted target genes involved in various metabolic pathways and linked to pathological conditions, including cognitive delay and fetal growth retardation, has been detected. Our findings highlight multi-level effects of NIC on hAFSCs, including epigenetic modifications, altered gene expression, and impaired cellular differentiation, which may contribute to long-term consequences of smoking in pregnancy and its potential impact on offspring health and development.

Targeting of human cancer stem cells predicts efficacy and toxicity of FDA-approved oncology drugs

Cancer remains the leading cause of death worldwide with approved oncology drugs continuing to have heterogenous patient responses and accompanied adverse effects (AEs) that limits effectiveness. Here, we examined >100 FDA-approved oncology drugs in the context of stemness using a surrogate model of transformed human pluripotent cancer stem cells (CSCs) vs. healthy stem cells (hSCs) capable of distinguishing abnormal self-renewal and differentiation. Although a proportion of these drugs had no effects (inactive), a larger portion affected CSCs (active), and a unique subset preferentially affected CSCs over hSCs (selective). Single cell gene expression and protein profiling of each drug's FDA recognized target provided a molecular correlation of responses in CSCs vs. hSCs. Uniquely, drugs selective for CSCs demonstrated clinical efficacy, measured by overall survival, and reduced AEs. Our findings reveal that while unintentional, half of anticancer drugs are active against CSCs and associated with improved clinical outcomes. Based on these findings, we suggest ability to target CSC targeting should be included as a property of early onco-therapeutic development.

Transcriptional insights from the human embryo identify laminin-511 as a suitable matrix for human trophoblast stem cell culture

The establishment of culture conditions to propagate self-renewing human trophoblast stem cells in long-term culture provides a paradigm for in vitro modelling of trophoblast. The extracellular matrix (ECM) is a critical determinant of cell identity and behaviour. Therefore, models aiming to reproduce cells in vitro should recapitulate the native cell-ECM microenvironment. Here, we mine human embryo transcriptional datasets to identify ECM components and cognate receptors expressed in the trophectoderm. Following, we identify laminin-511-E8 protein fragment as a physiologically relevant ECM capable of maintaining hTSCs in the stem cell state and retaining differentiation ability.

Human neural stem cells transplanted during the sequelae phase alleviate motor deficits in a rat model of cerebral palsy

AimsCerebral palsy (CP) is the most common physical disability in children, yet lacks an ideal animal model or effective treatment. This study aimed to develop a reliable CP model in neonatal rats and explore the effectiveness and underlying mechanisms of human neural stem cells (hNSCs) transplantation during the sequelae phase of CP. MethodsVasoconstrictor endothelin-1 (ET-1) was administered intracranially to the motor cortex and striatum of rats on postnatal day 5 to establish a CP model. hNSCs (5 × 105/5 μL) pretreated with hypoxia (5% O2 for 24 h) were transplanted near the infarct 3 weeks after ET-1 injury (the sequelae phase). The distribution and differentiation of hNSCs were observed after transplantation. Changes in neurotrophic factors, neurogenesis, angiogenesis, axonal plasticity, and motor function were analyzed. ResultsNeurobehavioral tests showed poor muscle strength and postural control in young ET-1 rats. Motor deficits of the left forelimb and gait abnormalities persisted into adulthood. Histopathological findings and MRI indicated the atrophy of the cortex, striatum, and adjacent corpus callosum in ET-1 rats. At 56 days after transplantation, hNSCs were widely distributed in the ipsilateral hemisphere, and differentiated into neurons, oligodendrocytes and astrocytes. Transplantation of hNSCs increased BDNF and VEGF expression, EdU+ cell number in the SVZ area, RECA-1+ vessel density and GAP-43 intensity around the lesion in ET-1 rats. The cylinder test revealed a significant increase in the left forelimb motor function from 28 days after transplantation, and the staircase and CatWalk tests showed improvements in fine motor function and gait parameters. ConclusionsIntracerebral injection of ET-1 modelled key functional and histopathological features of CP. hNSCs transplanted during the sequelae phase of CP resulted in long-term improvement in motor performance, possibly attributed to its capacity to stimulate neurotrophic factors, facilitate neurogenesis, angiogenesis, and promote axonal plasticity.

The role of the International Society for Stem Cell Research (ISSCR) guidelines in disease modeling.

Human stem cell-based modeling systems are valuable tools that can greatly improve the clinical translation of basic research. Importantly, the successful application of human stem cell-based models to biomedical research depends on the widespread adoption of ethical principles and practical standards. To achieve this outcome, the International Society for Stem Cell Research (ISSCR) provides a comprehensive set of recommendations that aim to promote the ethical usage of human stem cells and to ensure rigor and reproducibility within the field. Understanding and implementing these recommendations should be a top priority for investigators around the world.