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1.
Stem Cells ; 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39230167

RESUMO

Advanced bioinformatics analysis, such as systems biology (SysBio) and artificial intelligence (AI) approaches, including machine learning (ML) and deep learning (DL), is increasingly present in stem cell (SC) research. An approximate timeline on these developments and their global impact is still lacking. We conducted a scoping review on the contribution of SysBio and AI analysis to SC research and therapy development based on literature published in PubMed between 2000 and 2024. We identified an 8-10-fold increase in research output related to all three search terms between 2000 and 2021, with a 10-fold increase in AI-related production since 2010. Use of SysBio and AI still predominates in preclinical basic research with increasing use in clinically oriented translational medicine since 2010. SysBio- and AI-related research was found all over the globe, with SysBio output led by the United States (US, n=1487), United Kingdom (UK, n=1094), Germany (n=355), The Netherlands (n=339), Russia (n=215), and France (n=149), while for AI-related research the US (n=853) and UK (n=258) take a strong lead, followed by Switzerland (n=69), The Netherlands (n=37), and Germany (n=19). The US and UK are most active in SCs publications related to AI/ML and AI/DL. The prominent use of SysBio in ESC research was recently overtaken by prominent use of AI in iPSC and MSC research. This study reveals the global evolution and growing intersection between AI, SysBio, and SC research over the past two decades, with substantial growth in all three fields and exponential increases in AI-related research in the past decade.

2.
J Biomater Sci Polym Ed ; 35(5): 717-755, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38214998

RESUMO

Corneal diseases are a major cause of vision loss worldwide. Traditional methods like corneal transplants from donors are effective but face challenges like limited donor availability and the risk of graft rejection. Therefore, new treatment methods are essential. This review examines the growing field of bioprinting and biofabrication in corneal tissue engineering. We begin by discussing various bioprinting methods such as stereolithography, inkjet, and extrusion printing, highlighting their strengths and weaknesses for eye-related uses. We also explore how biological tissues are made suitable for bioprinting through a process called decellularization, which can be achieved using chemical, physical, or biological methods. The review then looks at natural materials, known as bioinks, used in bioprinting. We focus on materials like gelatin, collagen, fibrin, chitin, chitosan, silk fibroin, and alginate, examining their mechanical and biological properties. The importance of hydrogel scaffolds, particularly those based on collagen and other materials, is also discussed in the context of repairing corneal tissue. Another key area we cover is the use of stem cells in corneal regeneration. We pay special attention to limbal epithelial stem cells and mesenchymal stromal cells, highlighting their roles in this process. The review concludes with an overview of the latest advancements in corneal tissue bioprinting, from early techniques to advanced methods of delivering stem cells using bioengineered materials. In summary, this review presents the current state and future potential of bioprinting and biofabrication in creating functional corneal tissues, highlighting new developments and ongoing challenges with a view towards restoring vision.


Assuntos
Bioimpressão , Alicerces Teciduais , Alicerces Teciduais/química , Bioimpressão/métodos , Engenharia Tecidual/métodos , Colágeno/química , Células-Tronco , Regeneração , Impressão Tridimensional
3.
BMC Med Educ ; 22(1): 758, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335360

RESUMO

Stem cell therapeutics and regenerative medicine have taken a strong foothold in biomedicine. However, most physicians are currently not adequately prepared to identify, refer, and deliver safe regenerative therapies. To understand this gap, we sought to characterize published literature on current physician training in regenerative medicine. Our scoping review describes current training strategies to bridge the gap and integrate such education into medical curricula for adequate training.


Assuntos
Educação Médica , Médicos , Humanos , Medicina Regenerativa/educação , Currículo
4.
Cells ; 11(20)2022 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-36291115

RESUMO

Limbal stem cells constitute an important cell population required for regeneration of the corneal epithelium. If insults to limbal stem cells or their niche are sufficiently severe, a disease known as limbal stem cell deficiency occurs. In the absence of functioning limbal stem cells, vision-compromising conjunctivalization of the corneal epithelium occurs, leading to opacification, inflammation, neovascularization, and chronic scarring. Limbal stem cell transplantation is the standard treatment for unilateral cases of limbal stem cell deficiency, but bilateral cases require allogeneic transplantation. Herein we review the current therapeutic utilization of limbal stem cells. We also describe several limbal stem cell markers that impact their phenotype and function and discuss the possibility of modulating limbal stem cells and other sources of stem cells to facilitate the development of novel therapeutic interventions. We finally consider several hurdles for widespread adoption of these proposed methodologies and discuss how they can be overcome to realize vision-restoring interventions.


Assuntos
Doenças da Córnea , Limbo da Córnea , Humanos , Doenças da Córnea/terapia , Córnea , Células-Tronco , Homeostase
5.
Biomed Pharmacother ; 153: 113347, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35792394

RESUMO

Olfactory loss has been considered as the earliest complication for the aging process while underlying mechanisms and therapeutic strategies remain unclear. Given the correlation between microglial activation and olfactory dysfunction, here we investigated whether the immunomodulatory action of mesenchymal stem cells (MSCs) can rescue the olfactory impairment in old mice. The intranasal delivery of MSCs limited microglial activation and neuronal apoptosis in the olfactory bulb (OB), leading to improvement in olfaction. MSCs down-regulated the proportion of CD86+ microglia and prevented the maturation of cathepsin S, one of the inflammatory mediators in olfactory impairment, via the suppression of p38 MAPK signaling. Notably, old astrocytes could not prevent excessive microgliosis because the endogenous production of Galectin-1 (Gal1), one of the key microglia regulators secreted by astrocytes, was not sufficiently upregulated in the aged brain despite the presence of reactive astrogliosis. Considering that Gal1 is known as a potent paracrine factor of MSCs, we investigated whether MSC-derived Gal1 could compensate for defective astrocyte function in terms of microglial regulation. MSCs and their culture supernatant (MSC-CM) could regulate the direction of microglial differentiation by impeding the polarization towards the pro-inflammatory M1 type; notably, a selective Gal1 inhibitor OTX008 could hinder this phenomenon, indicating that Gal1 is involved in immunomodulation exerted by MSCs. Also, acute microglial activation within the OB upon LPS infusion was attenuated by MSC-CM in a Gal1-dependent manner. Our study demonstrates the therapeutic benefit of MSCs on age-related olfactory dysfunction and suggests Gal1 as a key mediator of the anti-inflammatory action of MSCs.


Assuntos
Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Transtornos do Olfato , Animais , Galectina 1 , Camundongos , Microglia , Olfato
6.
Front Vet Sci ; 9: 890704, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35747237

RESUMO

This double-blind, randomized, prospective clinical trial was conducted to obtain exploratory data comparing the efficacy of intra-articular allogeneic mesenchymal stem/stromal cells (MSC) to high molecular weight hyaluronic acid (HA) for the treatment of pain associated with canine osteoarthritis (OA). Objective gait analysis (%Body Weight Distribution, %BWD), accelerometry, clinical metrology instruments and veterinary exams were used as outcome measures during various time points throughout the 48-week study period. Fourteen dogs with elbow or coxofemoral OA were enrolled and assigned in a 2:1 ratio to the treatment groups. Each patient received a set of two injections 4 weeks apart. Self-limiting joint flare was observed in seven patients, with six of these in the MSC group. Ten patients completed all follow-up appointments. Both treatment groups showed evidence of mild improvement following the treatment, but the results were inconsistent among the various outcome measures assessed. Overall, dogs enrolled in the HA group showed greater improvement compared to the MSC group. The primary outcome measure, %BWD, showed evidence of improvement, when compared to baseline values, at 36 weeks after injection for the HA group only (p = 0.048, estimated difference: 4.7). Similarly, when treatment groups were compared, evidence of a difference between treatment groups (with the HA-group showing greater improvement) were identified for weeks 24 and 36 (p = 0.02 and 0.01, respectively). The small sample size of this exploratory study does not allow firm conclusions. However, until studies with larger sample sizes are available, the current literature combined with our data do not support the clinical use of intra-articular MSC therapy over high molecular weight HA for the treatment of canine OA at this time.

7.
Tissue Eng Regen Med ; 19(5): 1013-1031, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35511336

RESUMO

BACKGROUND: The mesenchymal stem cells (MSCs) have enormous therapeutic potential owing to their multi-lineage differentiation and self-renewal properties. MSCs express growth factors, cytokines, chemokines, and non-coding regulatory RNAs with immunosuppressive, anti-tumor, and migratory properties. MSCs also release several anti-cancer molecules via extracellular vesicles, that act as pro-apoptotic/tumor suppressor factors. This study aimed to identify the stem cell-derived secretome that could exhibit anti-cancer properties through molecular profiling of cargos in MSC-derived exosomes. METHODS: Human umbilical cord mesenchymal stem cells (hUCMSCs) were isolated from umbilical cord tissues and culture expanded. Subsequently, exosomes were isolated from hUCMSC conditioned medium and characterized by DLS, electron microscopy. Western blot for exosome surface marker protein CD63 expression was performed. The miRNA profiling of hUCMSCs and hUCMSC-derived exosomes was performed, followed by functional enrichment analysis. RESULTS: The tri-lineage differentiation potential, fibroblastic morphology, and strong expression of pluripotency genes indicated that isolated fibroblasts are MSCs. The isolated extracellular vesicles were 133.8 ± 42.49 nm in diameter, monodispersed, and strongly expressed the exosome surface marker protein CD63. The miRNA expression profile and gene ontology (GO) depicted the differential expression patterns of high and less-expressed miRNAs that are crucial to be involved in the regulation of apoptosis. The LCMS/MS data and GO analysis indicate that hUCMSC secretomes are involved in several oncogenic and inflammatory signaling cascades. CONCLUSION: Primary human MSCs released miRNAs and growth factors via exosomes that are increasingly implicated in intercellular communications, and hUCMSC-exosomal miRNAs have a critical influence in regulating cell death and apoptosis of cancer cells.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Neoplasias , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Exossomos/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/metabolismo , Proteômica , Cordão Umbilical
8.
ACS Appl Mater Interfaces ; 13(22): 25759-25770, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34036779

RESUMO

3D printing of stem cells provides a tremendous opportunity to tissue engineering in regenerative medicine. However, developing new bioactive materials to rationally augment stem cell viability is still an enormous challenge owing to the nutritionally deficient environment caused by the limited-penetration distance of nutrition when cells are encapsulated within biomaterials. In this work, a cationic conjugated polythiophene derivative, poly[3-(3'-N,N,N-triethylamino-1'-propyloxy)-4-methyl-2,5-thiophene hydrochloride] (PMNT), is designed and integrated into an anionic gelatin/alginate matrix to develop a new 3D bioprintable conjugated polymer ink Gel/Alg/PMNT, while the electrostatic interaction can assist PMNT to anchor inside ink without severe diffusional loss. In principle, PMNT is confirmed to promote human umbilical cord-derived mesenchymal stem cell (hMSC) proliferation in a serum-free medium by driving cell cycles and up-regulating gene expression in the pathways of biosynthesis and the metabolism. By employing the 3D bioprinting strategy together with hMSCs, the accelerated healing of full-thickness excisional wounds is further realized through the augmented-stem cell therapeutics utilizing Gel/Alg/PMNT ink, in which hMSC proliferation can be effectively promoted upon inductive stimulation of PMNT. The inherent highly bioactive and robust proliferation-promoted nature of the developed conjugated polymer ink Gel/Alg/PMNT significantly overcomes the nutritionally deficient environment, especially in 3D-printed large-scale architectures. The bioactive polythiophene material exhibits a unique capacity to promote stem cell proliferation without the need of serum, providing a new bioink for 3D bioprinting in tissue reconstructions.


Assuntos
Bioimpressão/métodos , Proliferação de Células , Células-Tronco Mesenquimais/citologia , Polímeros/química , Impressão Tridimensional/instrumentação , Tiofenos/química , Cordão Umbilical/citologia , Cicatrização , Animais , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual , Alicerces Teciduais/química
9.
Front Cell Neurosci ; 15: 811852, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35197824

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease worldwide. With the increasing trend of population aging, the estimated number of AD continues to climb, causing enormous medical, social and economic burden to the society. Currently, no drug is available to cure the disease or slow down its progression. There is an urgent need to improve our understanding on the pathogenesis of AD and develop novel therapy to combat it. Despite the two well-known pathological hallmarks (extracellular amyloid plaques and intracellular Neurofibrillary Tangles), the exact mechanisms for selective degeneration and loss of neurons and synapses in AD remain to be elucidated. Cumulative studies have shown neuroinflammation plays a central role in pathogenesis of AD. Neuroinflammation is actively involved both in the onset and the subsequent progression of AD. Microglia are the central player in AD neuroinflammation. In this review, we first introduced the different theories proposed for the pathogenesis of AD, focusing on neuroinflammation, especially on microglia, systemic inflammation, and peripheral and central immune system crosstalk. We explored the possible mechanisms of action of stem cell therapy, which is the only treatment modality so far that has pleiotropic effects and can target multiple mechanisms in AD. Mesenchymal stem cells are currently the most widely used stem cell type in AD clinical trials. We summarized the ongoing major mesenchymal stem cell clinical trials in AD and showed how translational stem cell therapy is bridging the gap between basic science and clinical intervention in this devastating disorder.

10.
Adv Sci (Weinh) ; 7(17): 2001365, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32995130

RESUMO

Human pluripotent stem cells (hPSCs) are a potent source of clinically relevant mesenchymal stem cells (MSCs) that confer functional and structural benefits in cell therapy and tissue regeneration. Obtaining sufficient numbers of MSCs in a short period of time and enhancing the differentiation potential of MSCs can be offered the potential to improve the regenerative activity of MSCs therapy. In addition, the underlying processes in the isolation and derivation of MSCs from hPSCs are still poorly understood and controlled. To overcome these clinical needs, an efficient and simplified technique on the isolation of MSCs from spontaneously differentiated human embryonic stem cells (hESCs) via integrin α5ß1 (fibronectin (FN) receptor)-to-FN interactions (hESC-FN-MSCs) is successfully developed. It is demonstrated that hESC-FN-MSCs exhibit a typical MSC surface phenotype, cellular morphology, with the whole transcriptome similar to conventional adult MSCs; but show higher proliferative capacity, more efficient trilineage differentiation, enhanced cytokine secretion, and attenuated cellular senescence. In addition, the therapeutic potential and regenerative capacity of the isolated hESC-FN-MSCs are confirmed by in vitro and in vivo multilineage differentiation. This novel method will be useful in the generation of abundant amounts of clinically relevant MSCs for stem cell therapeutics and regenerative medicine.

11.
Front Med ; 14(5): 664-673, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32761491

RESUMO

The Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 was identified in December 2019. The symptoms include fever, cough, dyspnea, early symptom of sputum, and acute respiratory distress syndrome (ARDS). Mesenchymal stem cell (MSC) therapy is the immediate treatment used for patients with severe cases of COVID-19. Herein, we describe two confirmed cases of COVID-19 in Wuhan to explore the role of MSC in the treatment of COVID-19. MSC transplantation increases the immune indicators (including CD4 and lymphocytes) and decreases the inflammation indicators (interleukin-6 and C-reactive protein). High-flow nasal cannula can be used as an initial support strategy for patients with ARDS. With MSC transplantation, the fraction of inspired O2 (FiO2) of the two patients gradually decreased while the oxygen saturation (SaO2) and partial pressure of oxygen (PO2) improved. Additionally, the patients' chest computed tomography showed that bilateral lung exudate lesions were adsorbed after MSC infusion. Results indicated that MSC transplantation provides clinical data on the treatment of COVID-19 and may serve as an alternative method for treating COVID-19, particularly in patients with ARDS.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus , Cuidados Críticos/métodos , Transplante de Células-Tronco Mesenquimais/métodos , Pandemias , Pneumonia Viral , Adulto , Idoso , Células Sanguíneas/fisiologia , Testes de Coagulação Sanguínea/métodos , COVID-19 , Teste para COVID-19 , China , Técnicas de Laboratório Clínico/métodos , Terapia Combinada , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/terapia , Feminino , Humanos , Masculino , Monitorização Imunológica/métodos , Oximetria/métodos , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/terapia , Dados Preliminares , SARS-CoV-2 , Índice de Gravidade de Doença , Avaliação de Sintomas/métodos , Resultado do Tratamento , Tratamento Farmacológico da COVID-19
12.
Stem Cells Dev ; 29(18): 1179-1189, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32723003

RESUMO

Pluripotent stem cells are promising candidates for cell-based regenerative therapies. To avoid rejection of transplanted cells, several approaches are being pursued to reduce immunogenicity of the cells or modulate the recipient's immune response. These include gene editing to reduce the antigenicity of cell products, immunosuppression of the host, or using major histocompatibility complex-matched cells from cell banks. In this context, we have investigated the antigenicity of H-Y antigens, a class of minor histocompatibility antigens encoded by the Y chromosome, to assess whether the gender of the donor affects the cell's antigenicity. In a murine transplant model, we show that the H-Y antigen in undifferentiated embryonic stem cells (ESCs), as well as ESC-derived endothelial cells, provokes T- and B cell responses in female recipients.


Assuntos
Células-Tronco Embrionárias/metabolismo , Rejeição de Enxerto/imunologia , Antígeno H-Y/metabolismo , Animais , Animais Recém-Nascidos , Linfócitos B/imunologia , Feminino , Tolerância Imunológica , Imunidade , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Células-Tronco , Análise de Sobrevida , Linfócitos T/imunologia
13.
Acta Neuropathol Commun ; 8(1): 84, 2020 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-32517808

RESUMO

Multiple Sclerosis (MS) causes neurologic disability due to inflammation, demyelination, and neurodegeneration. Immunosuppressive treatments can modify the disease course but do not effectively promote remyelination or prevent long term neurodegeneration. As a novel approach to mitigate chronic stage pathology, we tested transplantation of mouse induced neural stem cells (iNSCs) into the chronically demyelinated corpus callosum (CC) in adult mice. Male C57BL/6 mice fed 0.3% cuprizone for 12 weeks exhibited CC atrophy with chronic demyelination, astrogliosis, and microglial activation. Syngeneic iNSCs were transplanted into the CC after ending cuprizone and perfused for neuropathology 2 weeks later. Magnetic resonance imaging (MRI) sequences for magnetization transfer ratio (MTR), diffusion-weighted imaging (T2), and diffusion tensor imaging (DTI) quantified CC pathology in live mice before and after iNSC transplantation. Each MRI technique detected progressive CC pathology. Mice that received iNSCs had normalized DTI radial diffusivity, and reduced astrogliosis post-imaging. A motor skill task that engages the CC is Miss-step wheel running, which demonstrated functional deficits from cuprizone demyelination. Transplantation of iNSCs resulted in marked recovery of running velocity. Neuropathology after wheel running showed that iNSC grafts significantly increased host oligodendrocytes and proliferating oligodendrocyte progenitors, while modulating axon damage. Transplanted iNSCs differentiated along astrocyte and oligodendrocyte lineages, without myelinating, and many remained neural stem cells. Our findings demonstrate the applicability of neuroimaging and functional assessments for pre-clinical interventional trials during chronic demyelination and detect improved function from iNSC transplantation. Directly reprogramming fibroblasts into iNSCs facilitates the future translation towards exogenous autologous cell therapies.


Assuntos
Corpo Caloso/patologia , Corpo Caloso/fisiologia , Células-Tronco Pluripotentes Induzidas/transplante , Atividade Motora , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Células-Tronco Neurais/transplante , Remielinização , Animais , Astrócitos/patologia , Astrócitos/fisiologia , Diferenciação Celular , Corpo Caloso/diagnóstico por imagem , Modelos Animais de Doenças , Células-Tronco Pluripotentes Induzidas/fisiologia , Imageamento por Ressonância Magnética , Masculino , Camundongos Endogâmicos C57BL , Esclerose Múltipla/prevenção & controle , Células-Tronco Neurais/fisiologia , Oligodendroglia/patologia , Oligodendroglia/fisiologia
14.
Engineering (Beijing) ; 6(10): 1153-1161, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32292627

RESUMO

H7N9 viruses quickly spread between mammalian hosts and carry the risk of human-to-human transmission, as shown by the 2013 outbreak. Acute respiratory distress syndrome (ARDS), lung failure, and acute pneumonia are major lung diseases in H7N9 patients. Transplantation of mesenchymal stem cells (MSCs) is a promising choice for treating virus-induced pneumonia, and was used to treat H7N9-induced ARDS in 2013. The transplant of MSCs into patients with H7N9-induced ARDS was conducted at a single center through an open-label clinical trial. Based on the principles of voluntariness and informed consent, 44 patients with H7N9-induced ARDS were included as a control group, while 17 patients with H7N9-induced ARDS acted as an experimental group with allogeneic menstrual-blood-derived MSCs. It was notable that MSC transplantation significantly lowered the mortality of the experimental group, compared with the control group (17.6% died in the experimental group while 54.5% died in the control group). Furthermore, MSC transplantation did not result in harmful effects in the bodies of four of the patients who were part of the five-year follow-up period. Collectively, these results suggest that MSCs significantly improve the survival rate of H7N9-induced ARDS and provide a theoretical basis for the treatment of H7N9-induced ARDS in both preclinical research and clinical studies. Because H7N9 and the coronavirus disease 2019 (COVID-19) share similar complications (e.g., ARDS and lung failure) and corresponding multi-organ dysfunction, MSC-based therapy could be a possible alternative for treating COVID-19.

15.
Front Cell Dev Biol ; 8: 149, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32226787

RESUMO

Stem cell therapy has garnered much attention and application in the past decades for the treatment of diseases and injuries. Mesenchymal stem cells (MSCs) are studied most extensively for their therapeutic roles, which appear to be derived from their paracrine activity. Recent studies suggest a critical therapeutic role for extracellular vesicles (EV) secreted by MSCs. EV are nano-sized membrane-bound vesicles that shuttle important biomolecules between cells to maintain physiological homeostasis. Studies show that EV from MSCs (MSC-EV) have regenerative and anti-inflammatory properties. The use of MSC-EV, as an alternative to MSCs, confers several advantages, such as higher safety profile, lower immunogenicity, and the ability to cross biological barriers, and avoids complications that arise from stem cell-induced ectopic tumor formation, entrapment in lung microvasculature, and immune rejection. These advantages and the growing body of evidence suggesting that MSC-EV display therapeutic roles contribute to the strong rationale for developing EV as an alternative therapeutic option. Despite the success in preclinical studies, use of MSC-EV in clinical settings will require careful consideration; specifically, several critical issues such as (i) production methods, (ii) quantification and characterization, (iii) pharmacokinetics, targeting and transfer to the target sites, and (iv) safety profile assessments need to be resolved. Keeping these issues in mind, the aim of this mini-review is to shed light on the challenges faced in MSC-EV research in translating successful preclinical studies to clinical platforms.

16.
Int J Stem Cells ; 12(2): 315-330, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31242717

RESUMO

BACKGROUND AND OBJECTIVES: Mesenchymal stem cells (MSCs) are used to treat autoimmune or inflammatory diseases. Our aim was to determine the immunomodulatory mechanisms elicited by MSCs during inflammation. METHODS AND RESULTS: We cocultured MSCs with peripheral blood mononuclear cells for a mixed lymphocyte reaction or stimulated them by phytohemagglutinin. Morphological changes of MSCs and secretion of acetylcholine (ACh) from MSCs were measured. The effects of an ACh antagonist and ACh agonist on lymphocyte proliferation and proinflammatory-cytokine production were determined. The inflammatory milieu created by immune-cell activation caused MSCs to adopt a neuronlike phenotype and induced them to release ACh. Additionally, nicotinic acetylcholine receptors (nAChRs) were upregulated in activated peripheral blood mononuclear cells. We observed that ACh bound to nAChR on activated immune cells and led to the inhibition of lymphocyte proliferation and of proinflammatory-cytokine production. MSC-mediated immunosuppression through ACh activity was reversed by an ACh antagonist called α-bungarotoxin, and lymphocyte proliferation was inhibited by an ACh agonist, ACh chloride. CONCLUSIONS: Our findings point to a novel immunomodulatory mechanism in which ACh secreted by MSCs under inflammatory conditions might modulate immune cells. This study may provide a novel method for the treatment of autoimmune diseases by means of MSCs.

17.
Stem Cell Res Ther ; 9(1): 68, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29559008

RESUMO

BACKGROUND: While a shift towards non-viral and animal component-free methods of generating induced pluripotent stem (iPS) cells is preferred for safer clinical applications, there is still a shortage of reliable cell sources and protocols for efficient reprogramming. METHODS: Here, we show a robust episomal and xeno-free reprogramming strategy for human iPS generation from dental pulp stem cells (DPSCs) which renders good efficiency (0.19%) over a short time frame (13-18 days). RESULTS: The robustness of DPSCs as starting cells for iPS induction is found due to their exceptional inherent stemness properties, developmental origin from neural crest cells, specification for tissue commitment, and differentiation capability. To investigate the epigenetic basis for the high reprogramming efficiency of DPSCs, we performed genome-wide DNA methylation analysis and found that the epigenetic signature of DPSCs associated with pluripotent, developmental, and ecto-mesenchymal genes is relatively close to that of iPS and embryonic stem (ES) cells. Among these genes, it is found that overexpression of PAX9 and knockdown of HERV-FRD improved the efficiencies of iPS generation. CONCLUSION: In conclusion, our study provides underlying epigenetic mechanisms that establish a robust platform for efficient generation of iPS cells from DPSCs, facilitating industrial and clinical use of iPS technology for therapeutic needs.


Assuntos
Técnicas de Reprogramação Celular/métodos , Reprogramação Celular , Polpa Dentária/citologia , Epigênese Genética , Células-Tronco Mesenquimais/citologia , Plasmídeos/genética , Animais , Células Cultivadas , Humanos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Cultura Primária de Células/métodos
18.
Cell Rep ; 20(8): 1978-1990, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-28834758

RESUMO

There is growing interest in using embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) derivatives for tissue regeneration. However, an increased understanding of human immune responses to stem cell-derived allografts is necessary for maintaining long-term graft persistence. To model this alloimmunity, humanized mice engrafted with human hematopoietic and immune cells could prove to be useful. In this study, an in-depth analysis of graft-infiltrating human lymphocytes and splenocytes revealed that humanized mice incompletely model human immune responses toward allogeneic stem cells and their derivatives. Furthermore, using an "allogenized" mouse model, we show the feasibility of reconstituting immunodeficient mice with a functional mouse immune system and describe a key role of innate immune cells in the rejection of mouse stem cell allografts.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Imunidade Inata/imunologia , Células-Tronco Pluripotentes/metabolismo , Condicionamento Pré-Transplante/métodos , Animais , Modelos Animais de Doenças , Rejeição de Enxerto , Humanos , Camundongos
19.
Stem Cell Res Ther ; 8(1): 145, 2017 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-28619097

RESUMO

Adipose/fat tissue provides an abundant source of stromal vascular fraction (SVF) cells for immediate administration and can also give rise to a substantial number of cultured, multipotent adipose-derived stromal cells (ADSCs). Recently, both SVF and ADSCs have gained wide-ranging translational significance in regenerative medicine. Initially used for cosmetic breast enhancement, this mode of treatment has found use in many diseases involving immune disorders, tissue degeneration, and ischaemic conditions. In this review, we try to address several important aspects of this field, outlining the biology, technology, translation, and challenges related to SVF- and ADSC-based therapies. Starting from the basics of SVF and ADSC isolation, we touch upon recently developed technologies, addressing elements of novel methods and devices under development for point-of-care isolation of SVF. Characterisation of SVF cells and ADSCs is also an evolving area and we look into unusual expression of CD34 antigen as an interesting marker for such purposes. Based on reports involving different cells of the SVF, we draw a potential mode of action, focussing on angiogenesis since it involves multiple cells, unlike immunomodulation which is governed predominantly by ADSCs. We have looked into the latest research, experimental therapies, and clinical trials which are utilising SVF/ADSCs in conditions such as multiple sclerosis, Crohn's disease, peripheral neuropathy, osteoarthritis, diabetic foot ulcer, and so forth. However, problems have arisen with regards to the lack of proper regulatory guidelines for such therapies and, since the introduction of US Food and Drug Administration draft guidelines and the Reliable and Effective Growth for Regenerative Health Options that Improve Wellness (REGROW) Act, the debate became more public with regards to safe and efficacious use of these cells.


Assuntos
Tecido Adiposo/metabolismo , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/transplante , Medicina Regenerativa/métodos , Tecido Adiposo/patologia , Animais , Doença de Crohn/metabolismo , Doença de Crohn/patologia , Doença de Crohn/terapia , Pé Diabético/metabolismo , Pé Diabético/patologia , Pé Diabético/terapia , Humanos , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Esclerose Múltipla/terapia , Células-Tronco Multipotentes/patologia , Osteoartrite/metabolismo , Osteoartrite/patologia , Osteoartrite/terapia , Doenças do Sistema Nervoso Periférico/metabolismo , Doenças do Sistema Nervoso Periférico/patologia , Doenças do Sistema Nervoso Periférico/terapia , Células Estromais/metabolismo , Células Estromais/patologia , Células Estromais/transplante
20.
Front Neurol ; 7: 41, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27047447

RESUMO

Stem cell therapies can promote neural repair and regeneration, yet controversy regarding optimal cell source and mechanism of action has slowed clinical translation, potentially due to undefined cellular heterogeneity. Single-cell resolution is needed to identify clinically relevant subpopulations with the highest therapeutic relevance. We combine single-cell microfluidic analysis with advanced computational modeling to study for the first time two common sources for cell-based therapies, human NSCs and MSCs. This methodology has the potential to logically inform cell source decisions for any clinical application.

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