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Critical limb ischemia is an important clinical entity due to its association with increased morbidity and mortality. The mortality and amputation-free survival remains poor especially in those where revascularization is not an option. Recently, the role of cellular therapy has emerged as a promising therapeutic measure that may aid in wound healing and revascularization and improve functional outcomes.
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Isquemia , Cicatrização , Humanos , Cicatrização/fisiologia , Isquemia/terapia , Transplante de Células-Tronco/métodos , Resultado do TratamentoRESUMO
Rapid advances in biological knowledge and technological innovation have greatly advanced the fields of stem cell and gene therapies to combat a broad spectrum of neurologic disorders. Researchers are currently exploring a variety of stem cell types (e.g., embryonic, progenitor, induced pluripotent) and various transplantation strategies, each with its own advantages and drawbacks. Similarly, various gene modification techniques (zinc finger, TALENs, CRISPR-Cas9) are employed with various delivery vectors to modify underlying genetic contributors to neurologic disorders. While these two individual fields continue to blaze new trails, it is the combination of these technologies which enables genetically engineered stem cells and vastly increases investigational and therapeutic opportunities. The capability to culture and expand stem cells outside the body, along with their potential to correct genetic abnormalities in patient-derived cells or enhance cells with extra gene products, unleashes the full biological potential for innovative, multifaceted approaches to treat complex neurological disorders. In this review, we provide an overview of stem cell and gene therapies in the context of neurologic disorders, highlighting recent advances and current shortcomings, and discuss prospects for future therapies in clinical settings.
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Cardiovascular diseases (CVDs), including ischemic heart disease and stroke, are the leading cause of mortality worldwide, causing nearly 20 million deaths annually. Traditional therapies, while effective, have not curbed the rising prevalence of CVDs driven by aging populations and lifestyle factors. This review highlights innovative therapeutic strategies that show promise in improving patient outcomes and transforming cardiovascular care. Emerging pharmacological treatments, such as proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors and sodium-glucose co-transporter 2 (SGLT2) inhibitors, introduce novel mechanisms to complement existing therapies, significantly reducing cardiovascular events and mortality. These advancements emphasize the necessity of ongoing clinical trials and research to discover new therapeutic targets. Advanced biological therapies, including gene therapy, stem cell therapy, and RNA-based treatments, offer groundbreaking potential for repairing and regenerating damaged cardiovascular tissues. Despite being in various stages of clinical validation, early results are promising, suggesting these therapies could fundamentally change the CVD treatment landscape. Innovative medical devices and technologies, such as implantable devices, minimally invasive procedures, and wearable technology, are revolutionizing CVD management. These advancements facilitate early diagnosis, continuous monitoring, and effective treatment, driving care out of hospitals and into homes, improving patient outcomes and reducing healthcare costs. Personalized medicine, driven by genetic profiling and biomarker identification, allows for tailored therapies that enhance treatment efficacy and minimize adverse effects. However, the adoption of these emerging therapies faces significant challenges, including regulatory hurdles, cost and accessibility issues, and ethical considerations. Addressing these barriers and fostering interdisciplinary collaboration are crucial for accelerating the development and implementation of innovative treatments. Integrating emerging therapeutic strategies in cardiovascular care holds immense potential to transform CVD management. By prioritizing future research and overcoming existing challenges, a new era of personalized, effective, and accessible cardiovascular care can be achieved.
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Idiopathic pulmonary fibrosis (IPF) is characterised by lung scarring and stiffening, for which there is no effective cure. Based on the immunomodulatory and anti-fibrotic effects of induced pluripotent stem cell (iPSC) and mesenchymoangioblast-derived mesenchymal stem cells (iPSCs-MSCs), this study evaluated the therapeutic effects of iPSCs-MSCs in a bleomycin (BLM)-induced model of pulmonary fibrosis. Adult male C57BL/6 mice received a double administration of BLM (0.15â¯mg/day) 7-days apart and were then maintained for a further 28-days (until day-35), whilst control mice were administered saline 7-days apart and maintained for the same time-period. Sub-groups of BLM-injured mice were intravenously-injected with 1×106 iPSC-MSCs on day-21 alone or on day-21 and day-28 and left until day-35 post-injury. Measures of lung inflammation, fibrosis and compliance were then evaluated. BLM-injured mice presented with lung inflammation characterised by increased immune cell infiltration and increased pro-inflammatory cytokine expression, epithelial damage, lung transforming growth factor (TGF)-ß1 activity, myofibroblast differentiation, interstitial collagen fibre deposition and topology (fibrosis), in conjunction with reduced matrix metalloproteinase (MMP)-to-tissue inhibitor of metalloproteinase (TIMP) ratios and dynamic lung compliance. All these measures were ameliorated by a single or once-weekly intravenous-administration of iPSC-MSCs, with the latter reducing dendritic cell infiltration and lung epithelial damage, whilst promoting anti-inflammatory interleukin (IL)-10 levels to a greater extent. Proteomic profiling of the conditioned media of cultured iPSC-MSCs that were stimulated with TNF-α and IFN-γ, revealed that these stem cells secreted protein levels of immunosuppressive factors that contributed to the anti-fibrotic and therapeutic potential of iPSCs-MSCs as a novel treatment option for IPF.
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Background: Liver damage due to long-term viral infection, alcohol consumption, autoimmune decline, and other factors could lead to the gradual development of liver fibrosis. Unfortunately, until now, there has been no effective treatment for liver fibrosis. Mesenchymal stem cells, as a promising new therapy for liver fibrosis, can slow the progression of fibrosis by migrating to the site of liver injury and by altering the microenvironment of the fibrotic area. Aim: By including all relevant studies to date to comprehensively assess the efficacy of mesenchymal stem cells for the treatment of hepatic fibrosis and to explore considerations for clinical translation and therapeutic mechanisms. Methods: Data sources included PubMed, Web of Science, Embase, and Cochrane Library, and were constructed until October 2023. Data for each study outcome indicator were extracted for comprehensive analysis. Results: The overall meta-analysis showed that mesenchymal stem cells significantly improved liver function. Moreover, it inhibited the expression level of transforming growth factor-ß [SMD = 4.21, 95% CI (3.02,5.40)], which in turn silenced hepatic stellate cells and significantly reduced the area of liver fibrosis [SMD = 3.61, 95% CI (1.41,5.81)]. Conclusion: Several outcome indicators suggest that mesenchymal stem cells therapy is relatively reliable in the treatment of liver fibrosis. The therapeutic effect is cell dose-dependent over a range of doses, but not more effective at higher doses. Bone-marrow derived mesenchymal stem cells were more effective in treating liver fibrosis than mesenchymal stem cells from other sources. Systematic Review Registration: Identifier CRD42022354768.
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INTRODUCTION: Orthopedic conditions like osteoarthritis and bone defects pose significant challenges due to their impact on individuals' quality of life. Traditional treatments often provide only symptomatic relief, necessitating alternative therapies for long-term management. Stem cell therapy has grabbed attention for its regenerative and immunomodulatory properties, offering potential for tissue repair and functional restoration. OBJECTIVE: This study aims to assess the efficacy and safety of stem cell therapy for orthopedic conditions, specifically osteoarthritis and bone defects. MATERIALS AND METHODS: A retrospective cross-sectional study analyzed data from patients who underwent stem cell therapy for osteoarthritis or bone defects between January and September 2023. Outcome measures focused on pain and function improvements using tools such as Visual Analog Scale (VAS) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), alongside radiographic assessments. Adverse events, range of motion, quality of life, and demographic factors were also examined. Data were collected from electronic medical records while maintaining patient confidentiality. Descriptive statistics using SPSS (IBM Corp., Armonk, NY, USA) were employed to analyze patient characteristics, treatment variables, and outcomes, with statistical significance determined using Chi-square test and Independent t-test. RESULTS: Out of 50 individuals, the majority, i.e., 35 (or 70%), were diagnosed with osteoarthritis, while the remaining 15 (30%) had bone defects. Treatment outcomes showed significant improvements in pain and function, with a decrease in mean VAS and WOMAC scores at the six-month follow-up. Seven participants (28%) reported adverse events, and two participants (8%) experienced serious adverse events. CONCLUSION: Stem cell therapy shows promise for treating orthopedic conditions like osteoarthritis and bone defects. While demonstrating efficacy in pain management and functional improvement, safety considerations warrant further investigation and optimization of treatment protocols. Future research should focus on refining stem cell therapy techniques and addressing safety concerns to maximize its therapeutic potential in orthopedic practice.
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Adipose tissue-derived stem cells (ADSCs) represent a subset of the mesenchymal stem cells in every adipose compartment throughout the body. ADSCs can differentiate into various cell types, including chondrocytes, osteocytes, myocytes, and adipocytes. Moreover, they exhibit a notable potential to differentiate in vitro into cells from other germinal lineages, including endothelial cells and neurons. ADSCs have a wide range of clinical applications, from breast surgery to chronic wounds. Furthermore, they are a promising cell population for future tissue-engineering uses. Accumulating evidence indicates a decreased proliferation and differentiation potential of ADSCs with an increasing age, increasing body mass index, diabetes mellitus, metabolic syndrome, or exposure to radiotherapy. Therefore, the recent literature thoroughly investigates this cell population's senescence mechanisms and how they can hinder its possible therapeutic applications. This review will discuss the biological mechanisms and the physio-pathological causes behind ADSC senescence and how they can impact cellular functionality. Moreover, we will examine the possible strategies to invert these processes, re-establishing the full regenerative potential of this progenitor population.
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Tecido Adiposo , Diferenciação Celular , Senescência Celular , Células-Tronco Mesenquimais , Humanos , Tecido Adiposo/citologia , Animais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Engenharia Tecidual/métodosRESUMO
Stem cell therapy (SCT) is a promising solution for addressing health challenges in Africa, particularly non-communicable diseases (NCDs). With their regenerative potential, stem cells have the inherent capacity to differentiate into numerous cell types for tissue repair. Despite infrastructural, ethical, and legal challenges, SCT holds immense promise for managing chronic illnesses and deep-seated tissue injuries. The rising prevalence of NCDs in Africa highlights the need for innovative strategies and treatment options. SCT offers hope in combating conditions like burns, osteoarthritis, diabetes, Alzheimer's disease, stroke, heart failure and cancer, potentially reducing the burden of NCDs on the continent. Despite SCT's opportunities in Africa, there are significant obstacles. However, published research on SCT in Africa is scarce, but recent initiatives such as the Basic School on Neural Stem Cells (NSC) express interest in developing NSC research in Africa. SCT research in African regions, notably on neurogenesis, demonstrates a concentration on studying neurological processes in indigenous settings. While progress has been made in South Africa and Nigeria, issues such as brain drain and impediments to innovation remain. Clinical trials have investigated the efficacy of stem cell treatments, emphasising both potential benefits and limitations in implementing these therapies efficiently. Financing research, developing regulatory frameworks, and resolving affordability concerns are critical steps toward realizing the potential of stem cell treatment in Africa.
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Doenças não Transmissíveis , Transplante de Células-Tronco , Humanos , Doenças não Transmissíveis/terapia , África/epidemiologia , Transplante de Células-Tronco/métodos , Terapia Baseada em Transplante de Células e Tecidos/métodosRESUMO
Introduction: The therapeutic efficacy of mesenchymal stromal cells (MSCs) in inflammatory bowel disease is not completely known and is not consistent. Priming with inflammatory cytokines has been proposed to adapt MSCs to an inflammatory environment to have them ready to counteract it, but may have undesirable effects on MSCs, such as increased immunogenicity. In this study, we hypothesized that priming MSCs with inflamed intestinal tissue would more effectively enhance their therapeutic effect on intestinal inflammation. Methods: The capacity of canine adipose-derived MSCs (cADSCs) primed with colon tissue homogenates from mice with experimentally induced colitis or a combination of tumor necrosis factor-α and interferon-γ to inhibit T-cell proliferation was analyzed, along with their own apoptosis, proliferation, cell surface marker expression, and transcriptome. In addition, colitis mice were treated with the primed cADSCs to assess colitis severity and immune cell profile. Results: Priming with cytokines induced apoptosis, decreased cell proliferation, and major histocompatibility complex-II gene expression in cADSCs, but these adverse effects were mild or absent with colitis-tissue priming. cADSCs primed with colitis tissue reduced the severity of colitis via the induction of M2 macrophages and T-regulatory cells and suppression of T-helper (Th)1/Th17-cell responses, and their effects were comparable to those of cytokine-primed cells. Discussion: Our results emphasize the importance of the activation of MSCs by the appropriate microenvironment to maximize their therapeutic effect.
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Purpose: Rotator cuff (RC) tears cause fatty degeneration, aggravated by delayed treatment. Surgical repair alone cannot reverse fatty degeneration. It was aimed to test if local injections of satellite cell-derived myoblasts or satellite myoblasts (SM) from the deltoid region and mesenchymal stem cells (MSCs) from the subcutaneous abdominal fat pad would stimulate myogenesis and decrease adipogenesis in the rat model of fatty degenerated RC tear. Methods: A standardized RC tear surgery was performed on both shoulders of 24 Wistar albino rats at t = 0, and rats were followed for 8 weeks to create a chronic degeneration model. The animals were randomly divided into repair + SM and MSC (n = 12) or repair only (n = 12) groups. Transosseous repair with or without stem cell-based injection was performed on the right shoulder of all rats on week 8, with additional injections on weeks 9 and 10. The left shoulders were used as control. The animals were followed until week 14 for recovery. Results: Histological and histomorphometric analyses were performed in week 14. The repair + SM and MSC group had a significantly greater supraspinatus muscle mass than the repair only and control groups. The adipose tissue ratio was significantly lower in the repair + SM and MSC groups versus the repair only and control groups. Conclusion: Histologically, the repair + SM and MSC group had improved muscle and tendon organization. In treating chronically degenerated RC tear in a rat model, surgical repair combined with injections of SM and MSC improved fatty degeneration, tendon healing and myogenesis. Level of Evidence: Level III.
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Cardiac arrest (CA)-induced cerebral ischemia remains challenging with high mortality and disability. Neural stem cell (NSC) engrafting is an emerging therapeutic strategy with considerable promise that, unfortunately, is severely compromised by limited cell functionality after in vivo transplantation. This groundbreaking report demonstrates that metabolic glycoengineering (MGE) using the "Ac5ManNTProp (TProp)" monosaccharide analog stimulates the Wnt/ß-catenin pathway, improves cell adhesion, and enhances neuronal differentiation in human NSCs in vitro thereby substantially increasing the therapeutic potential of these cells. For the first time, MGE significantly enhances NSC efficacy for treating ischemic brain injury after asphyxia CA in rats. In particular, neurological deficit scores and neurobehavioral tests experience greater improvements when the therapeutic cells are pretreated with TProp than with "stand-alone" NSC therapy. Notably, the TProp-NSC group exhibits significantly stronger neuroprotective functions including enhanced differentiation, synaptic plasticity, and reduced microglia recruitment; furthermore, Wnt pathway agonists and inhibitors demonstrate a pivotal role for Wnt signaling in the process. These findings help establish MGE as a promising avenue for addressing current limitations associated with NSC transplantation via beneficially influencing neural regeneration and synaptic plasticity, thereby offering enhanced therapeutic options to boost brain recovery following global ischemia.
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Hypoxic-ischemic encephalopathy (HIE) is a brain lesion caused by inadequate blood supply and oxygen deprivation, often occurring in neonates. It has emerged as a grave complication of neonatal asphyxia, leading to chronic neurological damage. Nevertheless, the precise pathophysiological mechanisms underlying HIE are not entirely understood. This paper aims to comprehensively elucidate the contributions of hypoxia-ischemia, reperfusion injury, inflammation, oxidative stress, mitochondrial dysfunction, excitotoxicity, ferroptosis, endoplasmic reticulum stress, and apoptosis to the onset and progression of HIE. Currently, hypothermia therapy stands as the sole standard treatment for neonatal HIE, albeit providing only partial neuroprotection. Drug therapy and stem cell therapy have been explored in the treatment of HIE, exhibiting certain neuroprotective effects. Employing drug therapy or stem cell therapy as adjunctive treatments to hypothermia therapy holds great significance. This article presents a systematic review of the pathogenesis and treatment strategies of HIE, with the goal of enhancing the effect of treatment and improving the quality of life for HIE patients.
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BACKGROUND: There is no clear evidence on the comparative effectiveness of bone-marrow mononuclear cell (BMMNC) vs. mesenchymal stromal cell (MSC) stem cell therapy in patients with chronic heart failure (HF). METHODS: Using a systematic approach, eligible randomized controlled trials (RCTs) of stem cell therapy (BMMNCs or MSCs) in patients with HF were retrieved to perform a meta-analysis on clinical outcomes (major adverse cardiovascular events (MACE), hospitalization for HF, and mortality) and echocardiographic indices (including left ventricular ejection fraction (LVEF)) were performed using the random-effects model. A risk ratio (RR) or mean difference (MD) with corresponding 95% confidence interval (CI) were pooled based on the type of the outcome and subgroup analysis was performed to evaluate the potential differences between the types of cells. RESULTS: The analysis included a total of 36 RCTs (1549 HF patients receiving stem cells and 1252 patients in the control group). Transplantation of both types of cells in patients with HF resulted in a significant improvement in LVEF (BMMNCs: MD (95% CI) = 3.05 (1.11; 4.99) and MSCs: MD (95% CI) = 2.82 (1.19; 4.45), between-subgroup p = 0.86). Stem cell therapy did not lead to a significant change in the risk of MACE (MD (95% CI) = 0.83 (0.67; 1.06), BMMNCs: RR (95% CI) = 0.59 (0.31; 1.13) and MSCs: RR (95% CI) = 0.91 (0.70; 1.19), between-subgroup p = 0.12). There was a marginally decreased risk of all-cause death (MD (95% CI) = 0.82 (0.68; 0.99)) and rehospitalization (MD (95% CI) = 0.77 (0.61; 0.98)) with no difference among the cell types (p > 0.05). CONCLUSION: Both types of stem cells are effective in improving LVEF in patients with heart failure without any noticeable difference between the cells. Transplantation of the stem cells could not decrease the risk of major adverse cardiovascular events compared with controls. Future trials should primarily focus on the impact of stem cell transplantation on clinical outcomes of HF patients to verify or refute the findings of this study.
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Transplante de Medula Óssea , Insuficiência Cardíaca , Transplante de Células-Tronco Mesenquimais , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Insuficiência Cardíaca/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Transplante de Medula Óssea/métodos , Volume Sistólico , Resultado do Tratamento , Células-Tronco Mesenquimais/citologia , Função Ventricular EsquerdaRESUMO
BACKGROUND: Traumatic brain injury (TBI) is characterized by a disruption in the normal function of the brain due to an injury following a trauma, which can potentially cause severe physical, cognitive, and emotional impairment. Stem cell transplantation has evolved as a novel treatment modality in the management of TBI, as it has the potential to arrest the degeneration and promote regeneration of new cells in the brain. Wharton's Jelly-derived mesenchymal stem cells (WJ-MSCs) have recently shown beneficial effects in the functional recovery of neurological deficits. AIM: To evaluate the safety and efficiency of MSC therapy in TBI. METHODS: We present 6 patients, 4 male and 2 female aged between 21 and 27 years who suffered a TBI. These 6 patients underwent 6 doses of intrathecal, intramuscular (i.m.) and intravenous transplantation of WJ-MSCs at a target dose of 1 × 106/kg for each application route. Spasticity was assessed using the Modified Ashworth scale (MAS), motor function according to the Medical Research Council Muscle Strength Scale, quality of life was assessed by the Functional Independence Measure (FIM) scale and Karnofsky Performance Status scale. RESULTS: Our patients showed only early, transient complications, such as subfebrile fever, mild headache, and muscle pain due to i.m. injection, which resolved within 24 h. During the one year follow-up, no other safety issues or adverse events were reported. These 6 patients showed improvements in their cognitive abilities, muscle spasticity, muscle strength, performance scores and fine motor skills when compared before and after the intervention. MAS values, which we used to assess spasticity, were observed to statistically significantly decrease for both left and right sides (P < 0.001). The FIM scale includes both motor scores (P < 0.05) and cognitive scores (P < 0.001) and showed a significant increase in pretest posttest analyses. The difference observed in the participants' Karnofsky Performance Scale values pre and post the intervention was statistically significant (P < 0.001). CONCLUSION: This study showed that cell transplantation has a safe, effective and promising future in the management of TBI.
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Diabetic foot ulcers (DFUs) pose a critical medical challenge, significantly im-pairing the quality of life of patients. Adipose-derived stem cells (ADSCs) have been identified as a promising therapeutic approach for improving wound healing in DFUs. Despite extensive exploration of the mechanical aspects of ADSC therapy against DFU, its clinical applications remain elusive. In this review, we aimed to bridge this gap by evaluating the use and advancements of ADSCs in the clinical management of DFUs. The review begins with a discussion of the classification and clinical management of diabetic foot conditions. It then discusses the current landscape of clinical trials, focusing on their geographic distribution, reported efficacy, safety profiles, treatment timing, administration techniques, and dosing considerations. Finally, the review discusses the preclinical strategies to enhance ADSC efficacy. This review shows that many trials exhibit biases in study design, unclear inclusion criteria, and intervention protocols. In conclusion, this review underscores the potential of ADSCs in DFU treatment and emphasizes the critical need for further research and refinement of therapeutic approaches, with a focus on improving the quality of future clinical trials to enhance treatment outcomes and advance the field of diabetic wound care.
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Stem cell-based therapies have emerged as a promising approach for treating various neurological disorders by harnessing the regenerative potential of stem cells to restore damaged neural tissue and circuitry. This comprehensive review provides an in-depth analysis of the current state of stem cell applications in primary neurological conditions, including Parkinson's disease (PD), Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), stroke, spinal cord injury (SCI), and other related disorders. The review begins with a detailed introduction to stem cell biology, discussing the types, sources, and mechanisms of action of stem cells in neurological therapies. It then critically examines the preclinical evidence from animal models and early human trials investigating the safety, feasibility, and efficacy of different stem cell types, such as embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), neural stem cells (NSCs), and induced pluripotent stem cells (iPSCs). While ESCs have been studied extensively in preclinical models, clinical trials have primarily focused on adult stem cells such as MSCs and NSCs, as well as iPSCs and their derivatives. We critically assess the current state of research for each cell type, highlighting their potential applications and limitations in different neurological conditions. The review synthesizes key findings from recent, high-quality studies for each neurological condition, discussing cell manufacturing, delivery methods, and therapeutic outcomes. While the potential of stem cells to replace lost neurons and directly reconstruct neural circuits is highlighted, the review emphasizes the critical role of paracrine and immunomodulatory mechanisms in mediating the therapeutic effects of stem cells in most neurological disorders. The article also explores the challenges and limitations associated with translating stem cell therapies into clinical practice, including issues related to cell sourcing, scalability, safety, and regulatory considerations. Furthermore, it discusses future directions and opportunities for advancing stem cell-based treatments, such as gene editing, biomaterials, personalized iPSC-derived therapies, and novel delivery strategies. The review concludes by emphasizing the transformative potential of stem cell therapies in revolutionizing the treatment of neurological disorders while acknowledging the need for rigorous clinical trials, standardized protocols, and multidisciplinary collaboration to realize their full therapeutic promise.
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Doenças do Sistema Nervoso , Transplante de Células-Tronco , Humanos , Doenças do Sistema Nervoso/terapia , Transplante de Células-Tronco/métodos , Transplante de Células-Tronco/tendências , Animais , Terapia Baseada em Transplante de Células e Tecidos/métodos , Terapia Baseada em Transplante de Células e Tecidos/tendências , Células-Tronco Neurais/transplante , Células-Tronco Neurais/fisiologiaRESUMO
Retinitis pigmentosa (RP) is a group of genetic disorders characterized by progressive degeneration of photoreceptors and retinal pigment epithelium (RPE) cells. Its main clinical manifestations include night blindness and progressive loss of peripheral vision, making it a prevalent debilitating eye disease that significantly impacts patients' quality of life. RP exhibits significant phenotypic and genetic heterogeneity. For instance, numerous abnormal genes are implicated in RP, resulting in varying clinical presentations, disease progression rates, and pathological characteristics among different patients. Consequently, gene therapy for RP poses challenges due to these complexities. However, stem cells have garnered considerable attention in the field of RPE therapy since both RPE cells and photoreceptors can be derived from stem cells. In recent years, a large number of animal experiments and clinical trials based on stem cell transplantation attempts, especially cord blood mesenchymal stem cell (MSC) transplantation and bone marrow-derived MSC transplantation, have confirmed that stem cell therapy can effectively and safely improve the outer retinal function of the RP-affected eye. However, stem cell therapy also has certain limitations, such as the fact that RP patients may involve multiple types of retinal cytopathia, which brings great challenges to stem cell transplantation therapy, and further research is needed to solve various problems faced by this approach in the clinic. Through comprehensive analysis of the etiology and histopathological changes associated with RP, this study substantiates the efficacy and safety of stem cell therapy based on rigorous animal experimentation and clinical trials, while also highlighting the existing limitations that warrant further investigation.
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Introduction: Cell therapy has been increasingly considered to treat diseases, but it has been proven difficult to manufacture the same product at multiple manufacturing sites. Thus, for a wider implementation an alternative is to have one manufacturing site with a wide distribution to clinical sites. To ensure administration of a good quality cell therapy product with maintained functional characteristics, several obstacles must be overcome, which includes for example transfer of knowledge, protocols and procedures, site assessment, transportation and preparation of the product. Methods: As the preparatory work for a clinical trial in India using fetal mesenchymal stem cells (fMSCs) developed and manufactured in Sweden, we performed a site assessment of the receiving clinical site, transferred methods, developed procedures and provided training of operators for handling of the cell therapy product. We further developed a Pharmacy Manual to cover the management of the product, from ordering it from the manufacturer, through transport, reconstitution, testing and administration at the clinical site. Lastly, the effect of long-distance transport on survival and function of, as well as the correct handling of the cell therapy product, was evaluated according to the pre-determined and approved Product Specification. Results: Four batches of cryopreserved human fetal liver-derived fMSCs manufactured according to Good Manufacturing Practice and tested according to predetermined release criteria in Sweden, were certified and transported in a dry shipper at -150 °C to the clinical site in India. The transport was temperature monitored and took three-seven days to complete. The thawed and reconstituted cells showed more than 80% viability up to 3 h post-thawing, the cell recovery was more than 94%, the cells displayed the same surface protein expression pattern, differentiated into bone, had stable chromosomes and were sterile, which conformed with the data from the manufacturing site in Sweden. Conclusions: Our study shows the feasibility of transferring necessary knowledge and technology to be able to carry out a clinical trial with a cell therapy product in distant country. It also shows that it is possible to transport a cryopreserved cell therapy product over long distances and borders with retained quality. This extends the use of cryopreserved cell therapy products in the future.