Stem cell therapy prior to follicular unit hair transplantation on scarred tissue: a novel approach to a successful procedure.

Follicular unit hair extraction (FUE) is effective for hair restoration but is less successful on scarred tissue due to reduced vascularity and altered tissue architecture. Stem cell therapy can enhance tissue regeneration, possibly improving FUE outcomes on scarred tissue. This study investigated the impact of stem cell therapy prior to FUE on scarred tissue. Sixty patients with scalp scars from trauma or previous surgeries were divided into two groups. Group A (n = 30) received autologous stem cell therapy followed by FUE, while Group B (n = 30) underwent FUE without prior stem cell treatment. Autologous stem cells were harvested from patients' adipose tissue and injected into the scarred area four weeks before FUE. Outcomes were assessed at 3-, 6-, and 12-months post-transplantation, focusing on hair density, graft survival rate, and patient satisfaction. Histological examinations evaluated tissue regeneration. Group A showed significantly higher hair density (mean increase of 45%) and graft survival rates (87%) compared to Group B (mean increase of 25%, graft survival rate of 60%) at all follow-up points (P < 0.05). Histological analysis revealed enhanced neovascularization and reduced fibrosis in the stem cell-treated group, with 70% more new blood vessels and 50% less fibrotic tissue compared to the control group. Patient satisfaction scores were higher in Group A (average score of 8.5 out of 10) versus Group B (6.0), indicating better aesthetic outcomes and reduced scar visibility. Pre-treatment with autologous stem cell therapy significantly improved FUE effectiveness on scarred tissue, enhancing graft survival, hair density, and patient satisfaction. Further research is recommended to optimize this therapeutic strategy.

Burn wound healing using adipose-derived mesenchymal stem cells and manganese nanoparticles in polycaprolactone/gelatin electrospun nanofibers in rats.

Introduction: Wound healing is a major therapeutic concern in regenerative medicine. The current study aimed to investigate the second-degree burn wound treatment in rats using rat adipose- derived stem cells (ADSCs) and manganese nanoparticles (MnO2-NPs) in a polycaprolactone/gelatin electrospun nanofiber scaffold. Methods: After the synthesis of nanoparticles and electrospinning of nanofibers, the SEM analysis, contact angle, mechanical strength, blood compatibility, porosity, swelling, biodegradability, cell viability, and adhesion assays were performed. According to the results, the PCL/Gel/5%MnO2-NPs nanofiber (Mn-5%) was determined to be the most suitable scaffold. The ADSCs-seeded Mn-5% scaffolds were applied as a burn wound dressing. The wound closure rate, IL-1ß, and IL-6 level, hydroxyproline, and glycosaminoglycans content were measured, and the hematoxylin and eosin, Masson's trichrome, and immunohistochemistry stainings were carried out. Results: Based on the results, in Mn+S (ADSCs+PCL/Gel/5%MnO2-NPs nanofiber) and N+S (ADSCs+PCL/Gel nanofiber) groups, the IL-6 and IL-1ß levels were reduced, and the percentage of wound closure, glycosaminoglycans, and hydroxyproline content were increased compared to the control group (P<0.05). Also, the lowest amount of α-SMA was observed in these two groups, demonstrating stem cells' role in reducing α-SMA levels and thus preventing fibrosis. Moreover, the amount of α-SMA in the Mn+S group is lower than in the N+S group and, is closer to healthy skin. According to histology results, the best type of treatment was observed in the Mn+S group. Conclusion: In conclusion, the ADSCs-seeded PCL/Gel/5%MnO2-NPs scaffold demonstrated considerable therapeutic effects in burn wound healing.

Anti-aging based on stem cell therapy: A scoping review.

Stem cells are present in the tissues and organs and remain in a quiescent and undifferentiated state until it is physiologically necessary to produce new descendant cells. Due to their multipotency property, mesenchymal stem cells have attracted considerable attention worldwide due to their immunomodulation and therapeutic function in tissue regeneration. Stem cells secrete components such as paracrine factors, extracellular vesicles, and exosomes which have been shown to have anti-inflammatory, anti-aging, reconstruction and wound healing potentials in many in vitro and in vivo models. The pluripotency and immunomodulatory features of stem cells could potentially be an effective tool in cell therapy and tissue repair. Aging affects the capacity for self-renewal and differentiation of stem cells, decreasing the potential for regeneration and the loss of optimal functions in organisms over time. Current progress in the field of cellular therapy and regenerative medicine has facilitated the evolution of particular guidelines and quality control approaches, which eventually lead to clinical trials. Cell therapy could potentially be one of the most promising therapies to control aging due to the fact that single stem cell transplantation can regenerate or substitute the injured tissue. To understand the involvement of stem cells not only in tissue maintenance and disease but also in the control of aging it is important to know and identify their properties, functions, and regulation in vivo, which are addressed in this review.

Advancing towards HIV-1 remission: Insights and innovations in stem cell therapies.

Human immunodeficiency virus type 1 (HIV-1) continues to pose a significant global health challenge despite advances in combined antiretroviral therapy (cART), which has transformed HIV-1 infection from a fatal disease to a manageable chronic condition. However, cART is not curative, and its long-term use is associated with challenges such as pill burden, drug toxicities, and the emergence of drug-resistant viral strains. The persistence of active viral reservoirs necessitates lifelong treatment, highlighting the need for alternative therapeutic strategies capable of achieving HIV-1 remission or cure. Stem cell therapy has emerged as a promising approach to address these challenges by targeting latent viral reservoirs, restoring host immune function, and potentially achieving sustained viral suppression in the absence of cART. This review critically evaluates current scientific literature on stem cell therapies for HIV-1, focusing on three major approaches: 1) hematopoietic stem cell transplantation (HSCT), 2) gene therapy, and 3) cell-based immunotherapies. Each approach is examined in terms of its underlying mechanisms, clinical feasibility, recent advancements, and associated challenges. Furthermore, future research directions are discussed, emphasizing the optimization of the current treatment protocols, enhancement of safety and efficacy, and the importance of large-scale clinical trials with different cohorts (different HIV clades, different genders of participants, and pediatric HIV) to evaluate long-term outcomes that include effective and scalable HIV cure challenges. Collaborative efforts across multidisciplinary fields are needed to overcome existing barriers so to realize the full therapeutic potential of stem cell-based approaches for developing an effective and scalable remission or cure strategies.

A Comparison of Functional Outcomes in Rotator Cuff Repairs Using Adjunctive Bone Marrow Aspirate Concentrate vs. Bone Marrow Aspirate Concentrate With Platelet-Rich Plasma: A Systematic Review and Meta-Analysis.

Regenerative medicine, specifically bone marrow aspirate concentrate (BMAC) and platelet-rich plasma (PRP), has become a novel adjunct that orthopedic surgeons have started to use with surgical rotator cuff repairs (RCR). Thus, we are conducting this systematic review to determine if either RCRs with BMAC alone or with BMAC and PRP result in superior functional outcomes. We conducted a comprehensive search using five databases including PubMed, Web of Science, Embase, Scopus, and Cochrane. After duplicates were removed, 1205 studies were screened by title and abstract using Rayyan, resulting in three included studies (one BMAC with PRP and two BMAC only). Only studies that reported functional outcomes using the American Shoulder and Elbow Surgeons Shoulder Score and the University of California Los Angeles Shoulder Score were included. Changes in assessment scores from baseline to follow-up evaluation were quantified using the effect size and used in the meta-analysis for each group. Interpretation of treatment efficacy was represented using Cohen's d. The effect size of BMAC with PRP (Cohen's d = 2.19) was not significantly different (p = 0.76) from that of BMAC alone (Cohen's d = 2.35). Between-group differences in functional outcomes were Cohen's d = 0.16, which was not significant. Given the lack of superiority and the small sample size, more research is required before a conclusion can be drawn as to the benefits of combining PRP with BMAC for RCR. If functional outcomes are the same, using BMAC alone as an adjunct may be optimal to reduce resources used and cost. Future studies should be conducted with a larger pool as our primary limitation is that only three studies were included.

A comprehensive meta-analysis of stem cell therapy for liver failure: Assessing treatment efficacy and modality.

INTRODUCTION AND OBJECTIVES: This meta-analysis aims to evaluate the efficacy of stem cell therapy (SCT) for liver failure. MATERIALS AND METHODS: The study adhered to the recommended guidelines of the PRISMA statement. Eligible studies published prior to May 13, 2023, were comprehensively searched in databases including PubMed, Web of Science, and Embase. Quality assessment was conducted using the Cochrane risk-of-bias tool, and the standard mean differences were calculated for the clinical parameters. The hazard ratios were determined by extracting individual patient data from the Kaplan-Meier curve. RESULTS: A total of 2,937 articles were retrieved, and eight studies were included in the final analysis. Most of the studies focused on HBV-related liver failure and were randomized controlled trials. All studies utilized mesenchymal stem cells (MSCs), with the majority (62.5%) being allogeneic. The analysis revealed that combining stem cell therapy with standard medical treatment or plasma exchange significantly enhanced patient survival and reduced MELD scores. Specifically, allogeneic stem cells showed superior efficacy in improving survival outcomes compared to autologous stem cells. Furthermore, deep vessel injection plus a single injection demonstrated better effectiveness than peripheral vessel injection plus multiple injections in reducing MELD scores. CONCLUSIONS: This comprehensive analysis underscores the potential of MSC therapy in significantly improving survival and clinical outcomes in patients with liver failure, highlighting the superior benefits of allogeneic MSCs and deep vessel plus single injection administration.

Development of Neural Cells and Spontaneous Neural Activities in Engineered Brain-Like Constructs for Transplantation.

Stem cell transplantation has demonstrated efficacy in treating neurological disorders by generating functional cells and secreting beneficial factors. However, challenges remain for current cell suspension injection therapy, including uncontrollable cell distribution, the potential for tumor formation, and limited ability to treat spatial defects. Therefore, implants with programmable cell development, tailored 3D structure, and functionalized biomaterials have the potential to both control cell distribution and reduce or heal spatial defects. Here, a biomimetic material system comprising gelatin, alginate, and fibrinogen has been developed for neural progenitor cell constructs using 3D printing. The resulting constructs exhibit excellent formability, stability, and developmental functions in vitro, as well as biocompatibility and integration into the hippocampus in vivo. The controllability, reproducibility, and material composition of the constructs show potential for use in personalized stem cell-based therapies for defective neurological disorders, neural development research, disease modeling, and organoid-derived intelligent systems.

A Comparative Analysis of the Advances in Stem Cell Therapy in Plastic Surgery: A Systematic Review of Current Applications and Future Directions.

Stem cell (SC) therapy is revolutionizing the field of plastic surgery by harnessing the regenerative abilities of SCs derived from adipose tissue and bone marrow to boost tissue repair and enhance aesthetic outcomes. This groundbreaking method enhances results in procedures such as fat grafting, facial rejuvenation, and wound healing. As studies advance, SC therapy shows potential for more sophisticated uses in both reconstructive and cosmetic surgery. The objective of this review is to comprehensively examine the advances in SC therapy within the field of plastic surgery, highlighting its current applications and exploring future directions. The systematic review was conducted on SC therapy in plastic surgery adhering to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and specific search criteria. This systematic review highlights these main outcomes, and SC therapy in plastic surgery enhances tissue repair and aesthetic outcomes by utilizing mesenchymal SCs such as adipose-derived SCs (ADSCs) and bone marrow-derived SCs (BMSCs), with platelet-rich plasma (PRP) providing additional support. Techniques such as scaffolds and cellular reprogramming are employed to guide SC growth, enabling tailored tissue engineering for complex regenerative procedures. This innovative approach accelerates healing, reduces scarring in reconstructive surgeries, improves skin texture, and ensures the natural integration of treated areas, ultimately yielding enhanced aesthetic results and transforming facial rejuvenation processes. SC therapy in plastic surgery holds great promise, but challenges such as protocol standardization, cost, and regulations still need to be addressed. SC therapy is leading innovative advancements in plastic surgery, offering superior outcomes and improved quality of life for patients. Interestingly, the future of plastic surgery is focused on integrating SC therapy for personalized and transformative treatments. Furthermore, interdisciplinary collaboration among bioengineers, clinicians, and regulatory bodies is essential for overcoming challenges and advancing SC research into clinical practice.

Advances in stem cell therapy for diabetic foot.

Diabetic Foot Ulcers (DFU) represent a grave complication often encountered in the advanced stages of diabetes mellitus. They frequently lead to recurrent hospitalizations and, in severe cases, can result in life-threatening conditions such as infections, gangrene, and even amputation Diabetic foot ulcers (DFU), as a serious complication in the late stage of diabetes mellitus, are prone to lead to repeated hospitalization, and in severe cases, infection, gangrene, and even amputation. Although there are many methods for treating diabetic foot, there is no clear and effective method to reduce the amputation rate of diabetic foot patients. In recent years, advancements in the understanding of stem cell therapy for the treatment of DFU have shed light on its potential as a novel therapeutic approach. In recent years, as the research on stem cell therapy for diabetic foot is gradually deepening, stem cells are expected to become a new therapeutic method for treating DFU in the future. Their therapeutic effects are through promoting angiogenesis, secreting paracrine factors, controlling inflammation, promoting collagen deposition, and regulating immunity, etc. Despite numerous studies confirming the efficacy of stem cell therapy in treating DFU, there is still a need for the establishment of standardized treatment protocols. Although numerous studies have shown that stem cell therapy for DFU is real and effective, there has not yet been a standardized treatment protocol. This article reviews studies related to stem cell therapy for DFU, looking at the mechanism of action, types of stem cells, and modes of administration.

Long-term expanded hepatic progenitor cells ameliorate D-GalN/LPS-induced acute liver failure through repolarizing M1 macrophage to M2-Like phenotype via activation of the IL-10/JAK2/STAT3 signaling pathway.

Acute liver failure (ALF) is a devastating liver disease characterized by the rapid deterioration of hepatocytes, which causes a series of clinical complications, including hepatic dysfunction, coagulopathy, encephalopathy, and multiorgan failure. Cell-based therapy is a promising alternative as it can bridge patients until their livers regenerate, releasing immunomodulatory molecules to suppress inflammation. This study reports an iPSCs-derived long-term expanded hepatic progenitor cell (LTHepPCs), which can differentiate into hepatocyte-like cells (HLCs) in vivo. When introduced into drug-induced ALF models, LTHepPCs mitigate liver damage by modulating the local immune microenvironment. This is achieved by shifting macrophages/Kupffer cells towards an anti-inflammatory state, resulting in a decrease in the expression of inflammatory cytokines such as TNF-a, IL-1ß, and IL-8, and an increase in the expression of anti-inflammatory cytokines such as IL-10 and ARG-1. In vitro co-culturing of THP-1 or mBMDMs with LTHepPCs suggested that LTHepPCs could activate the anti-inflammatory state of macrophages/Kupffer cells via the IL-10/JAK2/STAT3 signaling pathway. Therefore, LTHepPC transplantation is a promising therapy for ALF patients.

Aptamer-Modified Tetrahedral Framework Nucleic Acid Synergized with TGF-ß3 to Promote Cartilage Protection in Osteoarthritis by Enhancing Chondrogenic Differentiation of MSCs.

Characterized by progressive and irreversible degeneration of the articular cartilage (AC), osteoarthritis (OA) is the most common chronic joint disease, and there is no cure for OA at present. Recent studies suggest that enhancing the recruitment of endogenous mesenchymal stem cells (MSCs) to damaged cartilage is a promising therapeutic strategy for cartilage repair. Tetrahedral framework nucleic acid (tFNA) is a novel DNA nanomaterial and has shown great potential in the field of biomedical science. Transforming growth factor-beta 3 (TGF-ß3), a vital member of the highly conserved TGF-ß superfamily, is considered to induce chondrogenesis. A 66-base DNA aptamer named HM69 is reported to identify and recruit MSCs. In this study, aptamer HM69-modified tFNAs were successfully self-assembled and used to load TGF-ß3 when the disulfide bonds combined. We confirmed the successful synthesis of the final composition, HM69-tFNA@TGF-ß3 (HTT), by PAGE, dynamic light scattering, and atomic force microscopy. The results of in vitro experiments showed that HTT effectively induced MSC proliferation, migration, and chondrogenic differentiation. In addition, HTT-treated MSCs were shown to protect the OA chondrocytes. In DMM mice, the injection of HTT improved the therapeutic outcome of mouse pain symptoms and AC degeneration. In conclusion, this study innovatively used the disulfide bonds combined with TGF-ß3 and tFNA, and an additional sequence HM69 was loaded on tFNA for the better-targeted recruitment of MSCs. HTT demonstrated its role in promoting the chondrogenesis of MSCs and cartilage protection, indicating that it might be promising for OA therapy.

Advancements in cell-based therapies for thermal burn wounds: a comprehensive systematic review of clinical trials outcomes.

BACKGROUND: Burn trauma is one of the major causes of morbidity and mortality worldwide. The standard management of burn wounds consists of early debridement, dressing changes, surgical management, and split-thickness skin autografts (STSGs). However, there are limitations for the standard management that inclines us to find alternative treatment approaches, such as innovative cell-based therapies. We aimed to systematically review the different aspects of cell-based treatment approaches for burn wounds in clinical trials. METHODS: A systematic search through PubMed, Medline, Embase, and Cochrane Library databases was carried out using a combination of keywords, including "Cell transplantation", "Fibroblast", "Keratinocyte", "Melanocyte", or "Stem Cell" with "Burn", "Burn wound", or "Burn injury". Firstly, titles and abstracts of the studies existing in these databases until "February 2024" were screened. Then, the selected studies were read thoroughly, and considering the inclusion and exclusion criteria, final articles were included in this systematic review. Moreover, a manual search was performed through the reference lists of the included studies to minimize the risk of missing reports. RESULTS: Overall, 30 clinical trials with 970 patients were included in our study. Considering the type of cells, six studies used keratinocytes, nine used fibroblasts, eight used combined keratinocytes and fibroblasts, one study used combined keratinocytes and melanocytes, five used combined keratinocytes and fibroblasts and melanocytes, and one study used mesenchymal stem cells (MSCs). Evaluation of the preparation type in these studies showed that cultured method was used in 25 trials, and non-cultured method in 5 trials. Also, the graft type of 17 trials was allogeneic, and of 13 other trials was autologous. CONCLUSIONS: Our study showed that employing cell-based therapies for the treatment of burn wounds have significant results in clinical studies and are promising approaches that can be considered as alternative treatments in many cases. However, choosing appropriate cell-based treatment for each burn wound is essential and depends on the situation of each patient.

Mesenchymal stem cell therapy for liver fibrosis need "partner": Results based on a meta-analysis of preclinical studies.

BACKGROUND: The efficacy of mesenchymal stem cells (MSCs) in treating liver fibrosis has been demonstrated in several clinical studies. However, their low survival and liver implantation rates remain problematic. In recent years, a large number of studies in animal models of liver fibrosis have shown that MSCs combined with drugs can improve the efficacy of MSCs in the treatment of liver fibrosis alone and inhibit its progression to end-stage liver disease. This has inspired new ways of thinking about treating liver fibrosis. AIM: To investigate the effectiveness and mechanisms of MSCs combined with drugs in treating liver fibrosis. METHODS: Data sources included four electronic databases and were constructed until January 2024. The subjects, interventions, comparators, outcomes, and study design principle were used to screen the literature, and the quality of the literature was evaluated to assess the risk of bias. Relevant randomised controlled trials were selected, and the final 13 studies were included in the final study. RESULTS: A total of 13 studies were included after screening. Pooled analysis showed that MSCs combined with drug therapy significantly improved liver function, promoted the repair of damaged liver tissues, reduced the level of liver fibrosis-related indexes, and effectively ameliorated hepatic fibrosis by modulating the hepatic inflammatory microenvironment, promoting the homing of MSCs, and regulating the relevant signaling pathways, and the treatment efficacy was superior to MSCs alone. However, the combined treatment statistics showed no ame-lioration in serum albumin levels (standardized mean difference = 0.77, 95% confidence interval: -0.13 to 1.68, P = 0.09). CONCLUSION: In conclusion, MSCs combined with drugs for treating liver fibrosis effectively make up for the shortcomings of MSCs in their therapeutic effects. However, due to the different drugs, the treatment mechanism and effect also differ. Therefore, more randomized controlled trials are needed to compare the therapeutic efficacy of different drugs in combination with MSCs, aiming to select the "best companion" of MSCs in treating hepatic fibrosis.

A Comparative Analysis of the Advances in Scar Reduction: Techniques, Technologies, and Efficacy in Plastic Surgery.

The study provides a comprehensive analysis of the latest methodologies and treatments aimed at improving scar management. Scar formation results from the replacement of normal skin with fibroblasts, leading to a structured unidirectional collagen bundle, as opposed to the collagen sheet matrix found in healthy skin. This review categorizes scars into hypertrophic scars and keloids, each with distinct pathophysiological characteristics. It highlights the importance of consistent scar assessment using scales such as the Vancouver Scar Scale and the Patient and Observer Scar Assessment Scale, emphasizing the need for standardized evaluation methods. The study systematically reviews various scar management techniques, ranging from traditional surgical methods to innovative treatments. Conventional approaches such as pressure garments and silicone gel sheeting are explored, noting their roles in maintaining hydration and occlusion. The efficacy of intralesional corticosteroid injections and laser therapies is discussed, with particular attention given to their combined use for optimal outcomes. The review also covers advanced techniques such as microneedling, platelet-rich plasma therapy, and stem cell-based treatments, detailing their mechanisms and potential benefits in scar remodelling. Additionally, the study underscores the emerging role of botulinum toxin A in both preventive and corrective scar treatments, offering promising results in reducing movement-induced scar exaggeration. The systematic review includes a thorough examination of existing literature, clinical trials, and meta-analyses to evaluate the effectiveness of these interventions. It concludes by calling for further research to refine these techniques and enhance their application in clinical practice, aiming to achieve better aesthetic and functional outcomes for patients with scars.

Modulation of human induced neural stem cell-derived dopaminergic neurons by DREADD reveals therapeutic effects on a mouse model of Parkinson's disease.

BACKGROUND: Stem cell-based therapy is a promising strategy for treating Parkinson's disease (PD) characterized by the loss of dopaminergic neurons. Recently, induced neural stem cell-derived dopaminergic precursor cells (iNSC-DAPs) have been emerged as a promising candidate for PD cell therapy because of a lower tumor-formation ability. Designer receptors exclusively activated by designer drugs (DREADDs) are useful tools for examining functional synaptic connections with host neurons. METHODS: DREADD knock-in human iNSCs to express excitatory hM3Dq and inhibitory hM4Di receptors were engineered by CRISPR. The knock-in iNSCs were differentiated into midbrain dopaminergic precursor cells (DAPs) and transplanted into PD mice. The various behavior test such as the Apomorphine-induced rotation test, Cylinder test, Rotarod test, and Open field test were assessed at 4, 8, or 12 weeks post-transplantation with or without the administration of CNO. Electrophysiology were performed to assess the integrated condition and modulatory function to host neurons. RESULTS: DREADD expressing iNSCs were constructed with normal neural stem cells characteristics, proliferation ability, and differentiation potential into dopaminergic neuorns. DAPs derived from DREADD expressing iNSC showed matched function upon administration of clozapine N-oxide (CNO) in vitro. The results of electrophysiology and behavioral tests of transplanted PD mouse models revealed that the grafts established synaptic connections with downstream host neurons and exhibited excitatory or inhibitory modulation in response to CNO in vivo. CONCLUSION: iNSC-DAPs are a promising candidate for cell replacement therapy for Parkinson's disease. Remote DREADD-dependent activation of iNSC-DAP neurons significantly enhanced the beneficial effects on transplanted mice with Parkinson's disease.

Mesenchymal stem cells: A promising therapeutic avenue for non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) is a pressing global health concern that is associated with metabolic syndrome and obesity. On the basis of the insights provided by Jiang et al, this editorial presents an exploration of the potential of mesenchymal stem cells (MSCs) for NAFLD treatment. MSCs have numerous desirable characteristics, including immunomodulation, anti-inflammatory properties, and tissue regeneration promotion, rendering them attractive candidates for NAFLD treatment. Recent preclinical and early clinical studies have highlighted the efficacy of MSCs in improving liver function and reducing disease severity in NAFLD models. However, MSC heterogeneity, long-term safety concerns, and unoptimized therapeutic protocols remain substantial challenges. Addressing these challenges through standardized protocols and rigorous clinical trials is essential to the safe and successful application of MSCs in NAFLD management. Continued research into MSC mechanisms and therapeutic optimization is required to improve treatments for NAFLD and related liver diseases.

Stem cell therapeutics and gene therapy for neurologic disorders.

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.

DNA-PKcs Inhibition Improves Sequential Gene Insertion of the Full-Length CFTR cDNA in Airway Stem Cells.

Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Although many people with CF (pwCF) are treated using CFTR modulators, some are non-responsive due to their genotype or other uncharacterized reasons. Autologous airway stem cell therapies, in which the CFTR cDNA has been replaced, may enable a durable therapy for all pwCF. Previously, CRISPR-Cas9 with two AAVs was used to sequentially insert two halves of the CFTR cDNA and an enrichment cassette into the CFTR locus. However, the editing efficiency was <10% and required enrichment to restore CFTR function. Further improvement in gene insertion may enhance cell therapy production. To improve CFTR cDNA insertion in human airway basal stem cells (ABCs), we evaluated the use of the small molecules AZD7648 and ART558 which inhibit non-homologous end joining (NHEJ) and micro-homology mediated end joining (MMEJ). Adding AZD7648 alone improved gene insertion by 2-3-fold. Adding both ART558 and AZD7648 improved gene insertion but induced toxicity. ABCs edited in the presence of AZD7648 produced differentiated airway epithelial sheets with restored CFTR function after enrichment. Adding AZD7648 did not increase off-target editing. Further studies are necessary to validate if AZD7648 treatment enriches cells with oncogenic mutations.

Regenerating the ailing heart: Stem cell therapies for hypoplastic left heart syndrome.

Hypoplastic left heart syndrome (HLHS) is a complex congenital heart defect (CHD) characterized by a spectrum of underdeveloped left-sided cardiac structures. It is a serious defect and warrants either 3-staged surgical palliation or a heart transplant. Despite numerous surgical advancements, long-term outcomes remain challenging and still have significant morbidity and mortality. There have been notable advancements in stem cell therapy for HLHS, including developments in diverse stem cell origins and methods of administration. Clinical trials have shown safety and potential benefits, including improved ventricular function, reduced heart failure, and fewer adverse events. Younger myocardium seems particularly receptive to stem cell signals, suggesting the importance of early intervention. This review explores the potential of emerging stem cell-based therapies as an adjunctive approach to improve the outcomes for HLHS patients.