Multilineage cells from human adipose tissue: implications for cell-based therapies

Enhanced susceptibility of porcine muscle-derived mesenchymal stem cells to Aujeszky's virus compared Vero cells

Mesenchymal stem cells (MSCs) can self-renew and differentiate into several lineages and can be isolated from different tissues such as bone marrow, adipose tissue, umbilical cord blood, and muscle. Herein, we established MSCs derived from miniature pig muscle (MpMu-MSCs) and assessed their response to Aujeszky's virus. We characterized the MpMu-MSCs based on their cellular morphology, proliferation properties, cell surface marker expression, and mesodermal differentiation potential. MpMu-MSCs demonstrated a fibroblast-like spindle shape and formed a homogeneous monolayer. They showed a considerable increase in cell proliferation over 16 passages. The cells expressed surface markers CD29, CD44, CD90, and CD105 and demonstrated mesodermal lineage differentiation capabilities. MpMu-MSCs demonstrated faster cytopathic effects than the Vero cells when infected with Aujeszky's virus. The virus titer in MpMu-MSCs was initiated at 101.4 TCID50/ml at 12 h post-infection (hpi) and increased to 106.6 TCID50/ml at 72 hpi. In Vero cells, it was initiated at 102.3 TCID50/ml at 48 hpi and increased to 103.8 TCID50/ml at 72 hpi. This study showed that the stem cells procured from miniature pig muscles exhibit MSC characteristics and that the established cells demonstrate higher susceptibility and virus titer to Aujeszky's virus than Vero cells, indicating their potential use in virus research.

Atoh8 expression inhibition promoted osteogenic differentiation of ADSCs and inhibited cell proliferation in vitro and rat bone defect models

Stem cell-based bone tissue engineering offers a promising approach for treating oral and cranio-maxillofacial bone defects. This study investigated the role of Atoh8, a key regulator in various cells, in the osteogenic potential of adipose-derived stem cells (ADSCs). ADSCs transfected with small interfering RNA (siRNA) targeting Atoh8 were evaluated for proliferation, migration, adhesion, and osteogenic capacity. In vivo, 20 SD rats were used to assess bone regeneration using Atoh8-knockdown ADSC sheets, with new bone formation quantified via micro-CT and histological analysis. Atoh8 knockdown in vitro reduced ADSC proliferation and migration but enhanced osteogenic differentiation and upregulation of osteogenic-related factors. This approach improved bone healing in rat defect models, accelerating repair both in vitro and in vivo. The findings underscore the clinical potential of ADSCs in bone tissue engineering and elucidate Atoh8's regulatory role in ADSC osteogenesis, providing a novel therapeutic strategy for enhancing bone regeneration through targeted modulation of stem cell differentiation pathways.

Evaluation of the management of rotator cuff injuries utilising superparamagnetic iron oxide tracking stem cells

BACKGROUND

The ultrastructure of the tendon-bone interface (TBI) is inherently complex. After arthroscopic reconstruction, it is often replaced by disorganized scar tissue, which increases the risk of re-tearing.Stem cell therapies offer a promising approach to regenerate the original tissue structure and enhance the healing environment. The effectiveness of these therapies depends on understanding the localization, proliferation, and overall behavior of the implanted stem cells. This study aimed to track the distribution of stem cells in a rat model of rotator cuff injury using Magnetic Resonance Imaging (MRI) and superparamagnetic iron oxide nanoparticles (SPIO) and to evaluate the mechanisms and therapeutic effects of stem cell therapy.

METHODS

Adipose-derived mesenchymal stem cells (ADSCs) were isolated and expanded, then labeled with SPIO at an optimized concentration. The visibility of these labeled cells was assessed via MRI, along with evaluations of their viability, potential toxicity, and migration capacity in vitro.For the in vivo study, rats with rotator cuff tears were divided into two groups: a control group that received a PBS injection, and a treatment group that received SPIO-labeled ADSCs (designated as S-A). MRI scans were conducted at 1, 2, and 4 weeks post-surgery, followed by histological analysis after the rats were euthanized. At 8 weeks post-surgery, rats were sacrificed, and their shoulder joints were analyzed biomechanically and histologically to assess the overall treatment efficacy.

RESULTS

SPIO nanoparticles were successfully incorporated into ADSCs, and MRI imaging demonstrated that these SPIO-labeled cells significantly enhanced MRI contrast without affecting cell viability, proliferation, or migration ability. Both MRI and histological analyses confirmed that the implanted stem cells survived and remained localized for at least two weeks. Further histological and biomechanical evaluations indicated that the stem cells facilitated the repair of the TBI. This repair process appeared to be mediated by an increase in M2 macrophage activity within the injured tissue, promoting improved local healing conditions.

CONCLUSION

This study confirms that labeling ADSCs with SPIO nanoparticles is an effective method for tracking these cells in vivo using MRI, providing a non-invasive approach to monitor the repair of injured TBI. Moreover, the localized survival of transplanted stem cells supports their role in enhancing TBI repair by modulating the local inflammatory response.

PCL-fibrin-alginate hydrogel based cell co-culture system for improving angiogenesis and immune modulation in limb ischemia

Stem cell therapy has demonstrated promise in regenerative medicine due to their ability to differentiate into various cell types and secrete growth factors. However, challenges such as poor survival rate of transplanted cells under ischemic and immune conditions limit its effectiveness. To address these issues, we developed a polycaprolactone (PCL)-fibrin-alginate matrix hydrogel, which combines adipose-derived stem cells and human umbilical vein endothelial cells with a PCL fiber, encapsulated within fibrin and alginate hydrogel to enhance cell survival, proliferation, and immune modulation. This structure offers protection to the encapsulated cells, supports angiogenesis, and modulates the immune response, significantly improving therapeutic outcomes in a mouse model of hindlimb ischemia. Our in vitro and in vivo results demonstrate the scaffold's ability to support cell viability, promote angiogenesis, and modulate inflammatory responses, indicating its potential as a promising platform for ischemic tissue repair and regenerative medicine. This innovative approach to cell-based therapy highlights the importance of scaffold design in enhancing the therapeutic efficacy of stem cell treatments for ischemic diseases.

Investigation of the stemness and wound-healing potential of long-term cryopreserved stromal vascular fraction cells

Introduction

Stromal vascular fraction (SVF), a heterogeneous cell population primarily derived from adipose tissue, is widely utilized in regenerative therapies for its wound-healing properties and accessibility. While its immediate availability is advantageous, repeated harvesting can be burdensome, especially for elderly patients, and the regenerative capacity of SVF declines with donor age. Long-term cryopreservation offers a potential solution by allowing the banking of SVF from younger donors for future use; however, the impact of this process on SVF functionality remains elusive. This study investigates the stemness and wound-healing potential of SVF following prolonged cryopreservation.

Methods

SVF cells were isolated from adipose tissue harvested from twelve patients and cryopreserved for either two months (short-term cryopreserved SVF, S-SVF) or 12-13 years (long-term cryopreserved SVF, L-SVF), with six patients in each group. In vitro assays assessed cell viability and stemness, while in vivo assays evaluated wound-healing ability by administering thawed SVF cells from each group to dorsal wounds in immunodeficient mice, compared with a control group. Non-parametric statistical tests analyzed the differences between groups.

Results

L-SVF exhibited significantly lower stemness compared to S-SVF. Importantly, the L-SVF group showed significantly improved wound healing compared with the control group, although the wound-healing effect of L-SVF was inferior to that of the S-SVF.

Conclusion

This study demonstrated that, despite reduced stemness, L-SVF retains partial wound-healing potential after 12-13 years of cryopreservation. These findings highlight the need for optimized cryopreservation protocols to enhance SVF viability and regenerative capacity for clinical applications.

Adipose derived stem cells - Sources, differentiation capacity and a new target for reconstructive and regenerative medicine

Adipose-derived stem cells (ADSCs) are mesenchymal stem cells (MSCs) derived from adipose tissue with mesenchymal lineage differentiation potential and remarkable potential in regenerative medicine. ADSCs are easily sourced from adipose tissue, share regenerative characteristics akin to other MSCs. Their convenient adherence to plastic culture flasks, coupled with their capacity for in vitro expansion and multi-lineage differentiation, underscores their promise as a robust tool for tissue repair and enhancement. The accessibility of human adipose tissue and the development of minimally invasive isolation protocols have further propelled the autologous use of ADSCs, fueling excitement in both organ repair and regenerative medicine. Consequently, research in ADSCsis experiencing rapid growth. A detailed overview of the current landscape of ADSCs isolation and differentiation capacity including the latest advancements in ADSCs usage, encompassing ongoing clinical investigations are important considerations to understand their potential to shape the landscape of regenerative medicine.

Current state of heart failure treatment: are mesenchymal stem cells and their exosomes a future therapy?

Heart failure (HF) represents the terminal stage of cardiovascular disease and remains a leading cause of mortality. Epidemiological studies indicate a high prevalence and mortality rate of HF globally. Current treatment options primarily include pharmacological and non-pharmacological approaches. With the development of mesenchymal stem cell (MSC) transplantation technology, increasing research has shown that stem cell therapy and exosomes derived from these cells hold promise for repairing damaged myocardium and improving cardiac function, becoming a hot topic in clinical treatment for HF. However, this approach also presents certain limitations. This review summarizes the mechanisms of HF, current treatment strategies, and the latest progress in the application of MSCs and their exosomes in HF therapy.

Beyond the Injury: How Does Smoking Impair Stem Cell-Mediated Repair Mechanisms? A Dual Review of Smoking-Induced Stem Cell Damage and Stem Cell-Based Therapeutic Applications

While the literature on molecular and clinical effects of smoking on the lungs and other organs has been expansively reviewed, there is no comprehensive compilation of the effects of smoking on stem cell (SC) populations. Recent research has shown that tobacco exposure severely compromises the function of SC populations, particularly those involved in tissue regeneration: mesenchymal SCs (MSCs), neural progenitors, and hematopoietic SCs. SC-based therapies have emerged as a promising approach to counteract smoking-related damage. In particular, MSCs have been extensively studied for their immunomodulatory properties, demonstrating the ability to repair damaged tissues, reduce inflammation, and slow disease progression in conditions such as chronic obstructive pulmonary disease. Combination therapies, which integrate pharmaceuticals with SC treatments, have shown potential in enhancing regenerative outcomes. This review examines the impact of smoking on SC biology, describes the processes impairing SC-mediated repair mechanisms and highlights recent advancements in SC-based therapies in the treatment of smoking-induced diseases. This review has two prongs: (1) it attempts to explain potential smoking-related disease etiology, and (2) it addresses a gap in the literature on SC-mediated repair mechanisms in chronic smokers.

Therapeutic Potential of Local and Systemic Adipose-Derived Mesenchymal Stem Cell Injections in a Rat Model of Experimental Periodontitis: Implications for Cardiac Function

Periodontitis is a common inflammatory disease that not only damages periodontal tissues but also induces systemic effects, including cardiac dysfunction. Mesenchymal stem cells (MSCs) offer regenerative potential due to their ability to differentiate, modulate immune responses, and secrete anti-inflammatory factors. However, the relative efficacy of local versus systemic MSC administration remains unclear. This study evaluated the therapeutic effects of adipose-derived MSCs (AD-MSCs) in a rat model of experimental periodontitis, comparing local and systemic administration. AD-MSCs were characterized based on morphology, surface marker expression, and differentiation potential. Ligature-induced periodontitis was established over 60 days, after which AD-MSCs (1 × 106 cells) were administered either supraperiosteally (local group) or intravenously (systemic group). Periodontal regeneration was assessed through clinical, radiographic, and histopathological analyses, while cardiac function was evaluated using echocardiography and histopathological examinations. Results demonstrated that local AD-MSC administration provided superior therapeutic benefits compared to systemic delivery. Locally administered cells significantly enhanced bone regeneration, reduced inflammation, and improved periodontal tissue architecture. In contrast, systemic administration offered moderate benefits but was less effective in restoring periodontal integrity. Similarly, in the heart, local treatment resulted in greater improvements in systolic function, as indicated by enhanced ejection fraction and fractional shortening, along with reduced myocardial fibrosis. Although systemic administration also provided cardioprotective effects, diastolic dysfunction persisted in both treatment groups. In conclusion, local AD-MSC administration proved more effective in regenerating periodontal tissues and mitigating cardiac dysfunction, highlighting its potential as an optimized therapeutic strategy for periodontitis and its systemic complications.

Understanding the Mechanisms of Chemotherapy-Related Cardiotoxicity Employing hiPSC-Derived Cardiomyocyte Models for Drug Screening and the Identification of Genetic and Epigenetic Variants

Chemotherapy-related cardiotoxicity (CTRTOX) is a profound and common side effect of cancer-based therapy in a subset of patients. The underlying factors and the associated mechanisms contributing to severe toxicity of the heart among these patients remain unknown. While challenges remain in accessing human subjects and their ventricular cardiomyocytes (CMs), advancements in human induced pluripotent stem cell (hiPSC)-technology-based CM differentiation protocols over the past few decades have paved the path for iPSC-based models of human cardiac diseases. Here, we offer a detailed analysis of the underlying mechanisms of CTRTOX. We also discuss the recent advances in therapeutic strategies in different animal models and clinical trials. Furthermore, we explore the prospects of iPSC-based models for identifying novel functional targets and developing safer chemotherapy regimens for cancer patients that may be beneficial for developing personalized cardioprotectants and their application in clinical practice.

Adipose-mesenchymal stem cells enhance the formation of auricular cartilage in vitro and in vivo

Patients suffering from microtia have limited treatment options for auricular reconstruction due to donor-site morbidity, complications, and unaesthetic outcome. Therefore, tissue engineering emerged as an alternative therapeutic option. Here, we generated and characterized human auricular cartilage using differentiated human adipose mesenchymal stem cells (hASCs) combined with human auricular chondrocytes. The differentiated hASCs were analysed for their morphology, phenotype, gene, and protein expression of chondrogenic markers, and biochemical composition at different time points in 2D and 3D in vitro. Importantly, we improved conditions for chondrogenic differentiation of hASCs in vitro to enhance their proliferation, survival, and deposition of cartilaginous-matrix proteins. In particular, gene expression analysis revealed an upregulation of cartilage oligomeric matrix protein (COMP) and aggrecan core protein (ACAN) in hASCs using the improved differentiation protocol in vitro. Additionally, we observed that co-seeding of hASCs with chondrocytes in a 1:5 ratio significantly enhanced the de novo auricular cartilage formation in a collagen-I bioink after 8 weeks on immunodeficient rat. In particular, the co-culture resulted in reduced shrinkage, and increased cartilage matrix production as confirmed by GAG deposition in vivo. Our results demonstrate that in co-cultures, hASCs stimulate cartilage formation due to a synergistic effect: hASCs' differentiation into chondrocytes and a trophic effect of hASCs on human auricular chondrocytes. Here we demonstrate the successful use of an hASC-chondrocyte co-culture technique for auricular cartilage tissue engineering in 3D collagen-I bioink. This co-culture approach omits the major drawbacks of traditional cartilage transplantation and thus, represents a fundamental step towards clinical translation.

TGF-β expressed by M2 macrophages promotes wound healing by inhibiting TSG-6 expression by mesenchymal stem cells

Wound healing involves the collaboration of multiple cells, including macrophages and fibroblasts, and requires the coordination of cytokines, growth factors, and matrix proteins to regulate the repair response. In this study, we investigated how M2 macrophages regulate expression of the anti-fibrotic and anti-inflammatory regulator tumor necrosis factor-α (TNF-α)-stimulated gene 6 (TSG-6) secreted by adipose tissue-derived stem cells (ASCs) during wound healing. Interleukin (IL)-4/IL-13, which is used to differentiate macrophage M2 phenotypes, increases TSG-6 in ASCs; however, M2 macrophages significantly decrease TSG-6 in ASCs. Transforming growth factor (TGF)-β expression was increased, and TNF-α expression was decreased in M2 macrophages. TGF-β inhibited IL-4/IL-13-induced ASC TSG-6 expression. In addition, TSG-6 suppressed TGF-β-triggered wound closure and fibrogenic responses in LX-2 cells. Collectively, TSG-6 inhibited wound healing, but M2 macrophage-expressed TGF-β prevented TSG-6 production from ASCs, which ultimately helped wound healing. Our results indicate that the balance of TNF-α and TGF-β levels during wound healing regulates TSG-6 production from ASCs, which may ultimately modulate the healing process. Our study findings could contribute to novel therapeutic strategies that manipulate the delicate balance between TNF-α and TGF-β to enhance wound repair and mitigate fibrosis.

Recent advances in the delivery of microRNAs via exosomes derived from MSCs, and their role in regulation of ferroptosis

Mesenchymal stem cell (MSC) therapy, with its unique properties, has garnered interest in cancer treatment. Exosomes (EXOs)-derived from MSC retain the paracrine components of MSCs and demonstrate increased stability, minimal immunogenicity, and low risk of unintended tumorigenesis. Enhanced endocytosis methods make them versatile delivery vehicles for therapeutic cargo. MSC-EXOs can either promote or inhibit carcinogenesis, mediated by paracrine factors and various RNA molecules, particularly microRNAs (miRNAs). The prospect of using MSC-EXOs as a delivery tool for antitumor miRNAs in solid tumor therapy is promising. Exosomes' intrinsic tumor-targeting abilities and low immunogenicity make them ideal for delivering miRNAs, which have shown potential as cancer therapeutics. miRNAs within MSC-EXOs molecules can stimulate tumor growth or induce non-apoptotic cell death pathways, such as ferroptosis, depending on context. Ferroptosis is a kind of controlled cell death that is associated with the pathophysiology of several illnesses and includes iron metabolism. There is growing evidence that miRNAs carried by exosomes derived from MSCs may control ferroptosis in tumor cells by altering key genes related to antioxidant defense, lipid peroxidation, and iron metabolism. Understanding their complex mechanisms in the tumor microenvironment and optimizing their cargo are critical steps toward harnessing their full therapeutic potential. This review provides a comprehensive overview of MSC-EXOs and their role in cancer treatment. We also discuss the potential of MSC-EXOs as delivery vehicles for miRNAs to enhance therapeutic efficacy, as well as the role of exosomal miRNAs in the induction of ferroptosis.

Markers for the angiogenic potential of fat grafts

BACKGROUND

Fat grafting is widely utilized in reconstructive and esthetic plastic surgery, typically with minimal complications. Nevertheless, the occurrence of fat necrosis is dependent on the technique used for fat extraction, tissue processing and the volume of the graft. The longevity of the graft critically depends on the presence of adipose-derived stromal cells (ADSC) and their promotion of a reconstituted vascular supply.

OBJECTIVE

This study seeks to determine whether there are differences in 13 angiogenesis-related adipokines based on their grouping by vascular endothelial growth factor (VEGF) expression levels.

METHODS

The expression of 14 adipokines related to angiogenesis in 12 cultured ADSCs was evaluated using Human Adipokine Profiler kits, which simultaneously detect 58 mediators. Adipokines of the high and low VEGF expression groups were evaluated for their expression of the remaining 13 angiogenic proteins.

RESULTS

We were able to show that there are significant differences in VEGFlow and VEGFhigh ADSCs regarding fibroblast growth factor 19 (p = 0.043) and insulin like growth factor binding protein 3 (p = 0.028). Furthermore, ADSCs with differentially highly expressed VEGF show a different pattern in the amount of protein levels regarding the 13 other adipokines observed.

CONCLUSION

The VEGF has been described as a key angiogenic factor in fat grafts that may be linked to successful grafting; however, two of the fat samples analyzed exhibited high expression of VEGF but lacked significant co-expression of a range of other angiogenic factors. Thus, the assessment of the expression of predisposing mediators for graft angiogenesis for wound healing or contouring should include further angiogenesis promoters aside VEGF as parameters.

Cool Fat, Hot Topic: A Systematic Review on Cryopreservation of Adipose Tissue

Autologous fat grafting is increasingly used in plastic, reconstructive, and esthetic surgery. Cryopreservation offers a promising solution for the long-term storage of adipose tissue, enabling multiple grafting sessions while minimizing patient discomfort associated with repeated liposuction for fat harvesting. This systematic review aims to analyze the current literature focusing on factors that influence the outcome of cryopreservation, including the use of cryoprotectants, the cooling and warming rate, the storage temperature, and the enrichment of cryopreserved fat grafts. A systematic search of the PubMed/MEDLINE database up to November 2024 was performed, including original preclinical and clinical studies written in English describing the cryopreservation of unprocessed or mechanically processed adipose tissue (macrofat, microfat, or nanofat). Eligible articles needed to describe the applied cryopreservation protocol, at least the storage temperature. Studies on cryopreservation of adipose-derived stem cells (ASCs), stromal vascular fraction, microvascular fragments, and other isolated components of adipose tissue were excluded. Data on cryoprotectants, cooling and warming rates, storage temperature, and eventual supplementation or enrichment of frozen fat were collected. Of the 679 records identified, 59 met the inclusion criteria. Adipose tissue cryopreservation at -80°C with a cryoprotectant, controlled slow cooling, and fast warming represented the most often applied protocol with encouraging outcomes in maintaining tissue survival and histological structure. Several studies indicated that the supplementation of frozen adipose tissue with ASCs improves tissue survival. Taken together, existing studies present diverse, and to some extent, conflicting results regarding cryopreservation protocols and their effects on adipose tissue viability. Hence, the ideal cryopreservation protocol for autologous fat remains to be established. Moreover, tailored protocols may be necessary for the cryopreservation of fat derivatives, such as nanofat.

The inconclusive superiority debate of allogeneic versus autologous MSCs in treating patients with HFrEF: a systematic review and meta-analysis of RCTs

BACKGROUND

Recent randomized controlled trials have consistently demonstrated the safety and potential efficacy of MSC therapy for heart failure patients. This study delves into mesenchymal stem cells' promising potential, offering a beacon of hope for the future of heart failure treatment with reduced ejection fraction (HFrEF).

METHODS

We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for this systematic review and meta-analysis. We searched four databases and registers for RCTs, including PubMed, EBSCO, clinicaltrials.gov, ICTRP, and other relevant websites. We then selected thirteen RCTs with 1184 participants based on our pre-defined inclusion/exclusion criteria. Two independent assessors extracted the data and performed a quality assessment. The data were then plotted for various outcomes, including death, hospitalization, major adverse cardiac events, pump function parameters, and 6-min walk distance.

RESULTS

The safety of MSC-based treatment has been consistently demonstrated with MSCs from autologous (AutoMSCs) and allogeneic (AlloMSCs) sources. This reassuring finding underscores the reliability of MSC-based therapy irrespective of their source. However, AutoMSCs showed a trend toward greater protective benefits. Subgroup analysis revealed no significant differences between AutoMSCs and AlloMSCs in improving LVEF; 0.86% (95% CI - 1.21-2.94%) for AlloMSCs versus 2.17% (- 0.48%; 95% CI - 1.33-5.67%) for AutoMSCs. AlloMSCs significantly reduced end-diastolic volume (LVEDV) by - 2.08 mL (95% CI - 3.52-0.64 mL). Only AlloMSCs significantly improved 6-min walking distance (6-MWD); 31.88 m (95% CI 5.03-58.74 m) for AlloMSCs versus 31.71 m (95% CI - 8.91-71.25 m) for AutoMSCs. The exclusion of studies using adipose-derived cells resulted in even better safety and a significant improvement in LVEF for AlloMSCs treatment.

CONCLUSION

Our findings suggest that AlloMSCs are at par with AutoMSCs in improving functional outcomes in heart failure patients. This underscores the need for future investigations in a larger patient cohort, emphasizing the urgency and importance of further research to fully understand the potential of MSCs in treating heart failure.

Therapeutic Potential of Mesenchymal Stem Cell and Tenocyte Secretomes for Tendon Repair: Proteomic Profiling and Functional Characterization In Vitro and In Ovo

Tendon ruptures and tendinopathies represent a major part of musculoskeletal injuries. Due to the hypovascular and hypocellular nature of tendons, the natural healing capacity is slow and limited. Cell-free approaches for tendon injuries are being investigated as the next generation of therapeutic treatments. The aim of this study was to compare the proteomic profiles and biological activities of two different secretomes, obtained from New Zealand white rabbit adipose-tissue-derived mesenchymal stem cells (ADSCs) or a 3:1 mixed culture of ADSCs and rabbit tenocytes. The secretomes were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and their functional properties, such as gene expression, migration and angiogenesis, were investigated in vitro in rabbit tenocytes and in ovo using the chicken chorioallantoic membrane (CAM) assay after stimulation with secretomes or medium control. Both secretomes had a positive effect on angiogenesis and showed similar changes in relative gene expression levels associated with extracellular matrix (ECM) remodeling. Proteomic data showed that the two secretomes were clearly distinguishable, with 182 proteins significantly differentially expressed. The ADSC secretome was more effective in enhancing tenocyte migration under both healthy and inflammatory conditions. In the upregulated protein fraction of the mixed secretome, the tendon-related protein biglycan (BGN) and tenascin C (TNC) were increased. Based on our results, the mixed secretome shows great potential for promoting tendon healing as its composition is more effective in enhancing ECM-related processes and tendon development than the secretome of ADSCs.

Systematic review and meta-analysis of the efficacy and safety of stem cell treatment of anal fistulas

BACKGROUND

Since anal fistulas can be challenging to treat; numerous innovative treatments have been proposed, including stem cell therapy. This systematic review aimed to assess pooled rates of fistula healing and adverse events associated with stem cell treatment.

METHODS

In this PRISMA-compliant systematic review we searched PubMed and Scopus for observational and randomized studies reporting outcomes of stem cell treatment for anal fistulas. The main outcome measures were successful healing and adverse effects of stem cell therapy.

RESULTS

In total, 43 studies incorporating 1160 patients (53.6% male) were included. Underlying fistula etiologies were Crohn's disease (30 studies) and cryptoglandular disease (12 studies). The main origin of stem cells was from adipose tissue (34 studies) or bone marrow (6 studies). The median follow-up duration was 12 months. The combined overall pooled healing rate was 58.1% (95% confidence interval (CI) 51.5-64.7%). The pooled healing rate for Crohn's fistulas was 60.4% (95% CI 54.7-66.2%) with adipose-derived stem cells and 63.6% (95% CI 49.4-77.7%) with bone-marrow-derived cells. The pooled healing rate for cryptoglandular fistulas was 53.8% (95% CI 35.5-72.2%) with adipose-derived stem cells. The pooled complication rate was 37.3% (95% CI 27.1-47.5%). Stem cells were associated with higher odds of anal fistula healing (odds ratio (OR): 1.81, p = 0.003) and similar odds of complications (OR: 1, p = 0.986) compared with controls.

CONCLUSIONS

Stem cell treatment of anal fistulas was associated with promising results. The healing rate in Crohn's anal fistulas was higher than in cryptoglandular fistulas. Bone-marrow-derived stem cells were associated with marginally better outcomes than were adipose-derived cells. This finding suggests that the autoimmune inflammatory etiology of Crohn's disease may respond better to autologous myoblasts than does the infectious etiology of cryptoglandular fistulas.

Research progress of extracellular vesicles derived from mesenchymal stem cells in the treatment of neurodegenerative diseases

As the world's population ages, neurodegenerative diseases are becoming more widely acknowledged as serious global health and socioeconomic issues. Although many resources have been devoted to the research of these illnesses, little progress has been made in the creation of novel diagnostic and therapeutic approaches. Extracellular vesicles (EVs) are released by all cell types and contain proteins, microRNAs, mRNAs, and other biologically active molecules. EVs play an important role in intercellular communication as well as in the regulation of neuroinflammation. Determining the mechanisms by which EVs contribute to the pathogenesis of neurodegenerative diseases will aid in the development of new therapeutic approaches and diagnostic tools. Mesenchymal stem cells (MSCs) have been shown in studies to control immunological responses, promote the growth of new brain connections, promote the production of blood vessels, and heal damaged tissues. There is growing evidence that MSCs' ability to treat patients is mostly due to the neurotrophic compounds they secrete through EVs. Since their tiny size allows them to pass through biological barriers and reach injured parts of the central nervous system, MSC-derived extracellular vesicles (MSC-EVs) retain many of the therapeutic qualities of their parent MSCs. This review discusses the role of EVs in neurodegenerative diseases and highlights the potential of MSC-EVs in the treatment of neurodegenerative diseases. The paper also examines the challenges that still need to be overcome and the prospects for using MSC-EVs to treat neurodegenerative illnesses.

Characterization of Fat Used for the Optimization of the Soft Tissue Envelope of the Nose in Rhinoplasty

Septorhinoplasty (SRP) is one of the most common aesthetic procedures worldwide. A thin or scarred soft tissue envelope, especially in the context of secondary SRP, can lead to unpredictable scarring, shrinkage, and discoloration of the skin. Other than the careful preparation of the soft tissue mantle, no gold standard exists to minimize the above-mentioned risks. Our aim was to create a thin "separation layer" between the nasal bridge (osseous and cartilaginous) and the skin envelope by autologous fat transfer with the addition of platelet-rich fibrin (PRF) to conceal small irregularities, to improve the quality of the skin soft tissue mantle, and to optimize the mobility of the skin. We report 21 patients who underwent SRP on a voluntary basis. All patients had either thin skin and/or revision SRP with scarring. Macroscopic fat harvested from the periumbilical or rib region was minced and purified. PRF was obtained by centrifugation of autologous whole blood samples and mixed with the fat to form a graft, which was then transferred to the nasal dorsum. Postoperative monitoring of graft survival included sonography and magnetic resonance imaging (MRI) of the nose. The harvested adipose tissue was also analyzed in vitro. In the postoperative follow-up after 1 year, survival of the adipose tissue was demonstrated in all patients by both sonography and MRI. The in vitro analysis showed interindividual differences in the quantity, size, and quality of the transplanted adipocytes. Camouflage of the nasal bridge by using adipose tissue was beneficial for the quality of the skin soft tissue mantle and hence represents a good alternative to known methods. Future aims include the ability to assess the quality of adipose tissue to be transplanted based on clinical parameters. Level of evidence: N/A.

Investigating the Viability of Fat Cells Over 1, 3, and 6 Months After Freezing at -18°C

BACKGROUND

Lipofilling is a natural, low-risk, and long-lasting method for filling, reconstructing, and improving soft tissues such as the face, with minimal discomfort for patients. Many plastic surgeons prefer autologous fat grafting in aesthetic surgery due to its availability, cost-effectiveness, biocompatibility, and absence of allergic and carcinogenic concerns. Despite the advantages of autologous fat injection, one of the main drawbacks is the variable persistence of injected fat tissue. Given the significant implications of this issue in advanced countries, this study aims to investigate the survival of fat cells after freezing at different time intervals (1, 3, and 6 months).

METHODS

Thirty female participants were enlisted for this research, and the viability of fat cell specimens was assessed at intervals of 0, 1, 3, and 6 months post-freezing at -18°C. The evaluation of viable adipocytes was conducted using the XTT assay, a live/dead staining method using fluorescence microscopy after staining with fluorescein diacetate (FDA) and propidium iodide (PI), along with histological analysis of fat tissue after freezing at the indicated time intervals.

RESULTS

The results showed that the viability of frozen fat samples decreases by 34%, 60%, and 80% after 1, 3, and 6 months, respectively, compared to non-frozen samples on Day 0.

CONCLUSIONS

The findings of this study underscore a rapid decline in adipocyte viability after storage at -18°C at different time intervals (1, 3, and 6 months), at which points only around 60%, 40%, and 20% of fat cells remained viable, respectively. These results suggest that current fat preservation techniques utilizing either a -18°C freezer are not sufficient for maintaining the long-term viability of adipocytes, and alternative cryopreservation methods are needed to preserve fat cells.

NAT10-mediated N4-acetylcytidine modification in KLF9 mRNA promotes adipogenesis

Dysfunctional adipogenesis is a major contributor of obesity. N-acetyltransferase 10 (NAT10) plays a crucial role in regulating N4-acetylcysteine (ac4C) modification in tRNA, 18SrRNA, and mRNA. As the sole "writer" in the ac4C modification process, NAT10 enhances mRNA stability and translation efficiency. There are few reports on the relationship between NAT10 and adipogenesis, as well as obesity. Our study revealed a significant upregulation of NAT10 in adipose tissues of obese individuals and high-fat diet-fed mice. Furthermore, our findings revealed that the overexpression of NAT10 promotes adipogenesis, while its silencing inhibits adipogenesis in both human adipose tissue-derived stem cells (hADSCs) and 3T3-L1 cells. These results indicate the intimate relationship between NAT10 and obesity. After silencing mouse NAT10 (mNAT10), we identified 30 genes that exhibited both hypo-ac4C modification and downregulation in their expression, utilizing a combined approach of acRIP-sequencing (acRIP-seq) and RNA-sequencing (RNA-seq). Among these genes, we validated KLF9 as a target of NAT10 through acRIP-PCR. KLF9, a pivotal transcription factor that positively regulates adipogenesis. Our findings showed that NAT10 enhances the stability of KLF9 mRNA and further activates the CEBPA/B-PPARG pathway. Furthermore, a dual-luciferase reporter assay demonstrated that NAT10 can bind to three motifs of mouse KLF9 and one motif of human KLF9. In vivo studies revealed that adipose tissue-targeted mouse AAV-NAT10 (AAV-shRNA-mNAT10) inhibits adipose tissue expansion in mice. Additionally, Remodelin, a specific NAT10 inhibitor, significantly reduced body weight, adipocyte size, and adipose tissue expansion in high-fat diet-fed mice by inhibiting KLF9 mRNA ac4C modification. These findings provide novel insights and experimental evidence of the prevention and treatment of obesity, highlighting NAT10 and its downstream targets as potential therapeutic targets.

Effects of photobiomodulation on adipocytic infiltration in sites of skin healing: in vivo experimental study

Adipocyte infiltration consists of a temporary increase in the number of adipocytes in the microenvironment of tissue injury. There is already evidence in the literature of adipocytes' participation in promoting the inflammatory response, and parallelly laser photobiomodulation can benefit the tissue repair process. This study aimed to chronologically analyze adipocytic infiltration in the repair of photobiomodulated skin wounds experimentally induced in rats through histomorphometric analysis. The sample consisted of 20 rats divided into 2 groups: control group and group subjected to laser photobiomodulation. The skin portions of the back of rats were processed and stained with Hematoxylin-Eosin in 4 μm thick sections including the surgical wound 5 and 10 days after the proposed treatments. Qualitative and quantitative analyses were performed by capturing images of tissue sections, describing the organizational pattern of adipocytes around the surgical wound and counting individual adipocytes in the connective tissue in formation. Adipocytic infiltration was observed in both experimental groups on the 5th day, with a decrease on the 10th day. The group treated with photobiomodulation presented a greater number of adipocytes compared to the control group, in both periods analyzed. The findings of the present study seem to corroborate the literature, which indicates that adipose cells might stimulate inflammation and repair, and photobiomodulation can enhance these effects, since it aids the process of adipocytic infiltration in the injured area. Clinical trial number: Not applicable.

Therapeutic and Pharmaceutical Potential of Scutellaria baicalensis-Derived Exosomes for Oily Skin Disorders

BACKGROUND

Fine dust exposure worsens oily skin by disrupting lipid metabolism and triggering oxidative inflammation. Scutellaria baicalensis extract-induced exosomes (SBEIEs) have shown anti-inflammatory effects by suppressing reactive oxygen species (ROS) and lipid-regulating properties, making them potential therapeutic agents.

METHODS

Exosomes from fibroblasts treated with SBEIEs and PM10 were tested on macrophages, adipose-derived stem cells (ASCs), and T lymphocytes. ELISA, flow cytometry, and PCR measured cytokines and gene expression. A 10-day clinical trial evaluated skin hydration, oiliness, and inflammation.

RESULTS

SBEIEs increased IRF3 (1.6 times) and suppressed PPARγ in ASCs while enhancing lipolysis markers. Sebaceous gland activity (squalene synthase) decreased by 10%. Macrophages showed increased IRF3, IFN-β, and IL-10 (2.1 times). T cells secreted IL-4 and IL-22 (2-2.33 times). Clinically, SBEIEs improved hydration (21%), reduced oiliness (1.6 times), and decreased inflammation (2.2 times).

CONCLUSIONS

SBEIEs effectively regulate lipid metabolism, cytokines, and immune responses, showing promise to treat oily and inflamed skin caused by fine dust exposure. Further studies are needed for clinical applications.

A Comprehensive Exploration of the Biological Effects of Adipose-Derived Stem Cells in the Treatment of Systemic Sclerosis

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by vasculopathy and tissue fibrosis affecting the skin and internal organs. Genetic and environmental factors influence susceptibility, severity, and onset. Current treatments are limited and not always effective, leading researchers to investigate new approaches, such as the use of adipose-derived mesenchymal stem cells (ADSCs) through fat grafting. This review seeks to understand how ADSCs may impact the development and progression of SSc, with a particular focus on how these cells could alter immune responses and reduce fibrosis. ADSCs have been found to affect various immune cells, including T cells, B cells, macrophages, and dendritic cells, by releasing cytokines, chemokines, and growth factors. These interactions generally suppress inflammation and promote a regulatory immune environment. Additionally, ADSCs can influence the extracellular matrix, helping to prevent fibrosis through signaling molecules like exosomes. ADSCs show promise as a treatment for SSc due to their ability to modulate the immune system and reduce fibrosis. Early clinical studies are encouraging, but more research is needed to fully understand how they work and to develop effective treatment protocols.

Advancements in Regenerative Therapies for Orthopedics: A Comprehensive Review of Platelet-Rich Plasma, Mesenchymal Stem Cells, Peptide Therapies, and Biomimetic Applications

Background/Objectives: Regenerative therapies have gained interest in orthopedic applications for their potential to enhance tissue regeneration, functional recovery, and pain modification. This review evaluates the clinical efficacy of platelet-rich plasma (PRP), mesenchymal stem cells (MSCs), peptide-based treatments, and biomimetic materials in orthopedic care, with a focus on pain reduction and functional outcomes. Methods: A structured literature search in PubMed (January 2009-January 2025) identified 160 studies. After applying inclusion criteria prioritizing randomized controlled trials (RCTs) and clinical trials, 59 studies were included: 20 on PRP, 20 on MSCs, 10 on peptide therapies, and 7 on biomimetics. Data extraction focused on pain reduction and functional recovery, with risk of bias assessed using the Cochrane Risk of Bias (RoB) tool and ROBINS-I tool. A random-effects meta-regression analysis was conducted to evaluate the impact of therapy type, sample size, and risk of bias on reported pain reduction outcomes. Results: Meta-regression analysis identified MSC therapy as the most effective intervention for pain reduction (β = 8.45, p < 0.05), with PRP and peptide-based therapies showing moderate improvements, and biomimetic therapies demonstrating the lowest effect. PRP provided short-term pain relief, particularly in acute injuries and tendon repair, though inconsistencies in preparation methods limited success in chronic conditions. MSC therapies demonstrated cartilage regeneration and early osteoarthritis improvement, but high costs and ethical concerns remain barriers to widespread adoption. Peptide-based therapies and biomimetic materials, including engineered scaffolds and autologous protein solutions, showed promise for infection control and wound healing, though further research is needed to optimize dosing, delivery methods, and long-term safety. Conclusions: Regenerative therapies offer significant potential in orthopedic care, with MSC therapies demonstrating the most reliable regenerative effects, PRP providing short-term symptomatic relief, and peptide-based and biomimetic treatments emerging as promising adjuncts. However, standardized protocols and large-scale clinical trials are needed to establish long-term efficacy and improve clinical translation for broader adoption.

Rapid osteoinduction of human adipose-derived stem cells grown on bioactive surfaces and stimulated by chemically modified media flow

Adipose-derived stem cells (ASCs) provide an ample, easily accessible source of multipotent cells, an alternative to bone marrow-derived stromal cells (BMSCs), capable of differentiating into osteoblasts. However, the osteogenic potential of ASCs is reportedly lower than that of BMSCs and protocols to effectively differentiate ASCs into osteoblasts are in high demand. Here, we present novel strategies for effective osteogenic differentiation of human ASCs by combining their culture on bioactive growth surfaces with their treatment with specific supplements in osteogenic medium and application of fluid shear stress. Human ASCs were cultured on PLGA-based composites containing 50 wt% sol-gel bioactive glasses (SBGs) from the SiO2-CaO±P2O5 system, either unmodified or modified with 5 wt% ZnO or SrO. The osteogenic medium was supplemented with recombinant human bone morphogenetic protein 2 (BMP-2), MEK1/2 kinase inhibitor (PD98059) and indirect Smurf1 inhibitor (Phenamil). Fluid shear stress was applied with a standard horizontal rocker. ASC culture on SBG-PLGA composites along with the osteogenic medium supplements enhanced the expression of both early and late osteogenic markers. Modification of SBG with either SrO or ZnO further enhanced osteogenic gene expression compared to ASCs cultured on composites containing unmodified SBGs. Notably, the application of fluid shear stress synergistically strengthened the osteogenic effects of bioactive composites and medium supplements. We also show that the presented culture strategies can drive ASCs toward osteoblastic cells in a 3-day culture period and provide mineralizing osteoblasts through a short, 7-day ASC preculture on bioactive composites. Our results also indicate that the applied osteogenic treatment leads to the phosphorylation of β-catenin and CREB or the COX-2 expression. We believe the presented strategies are feasible for rapid ASC differentiation to early osteoblasts or mineralizing osteoblastic cells for various potential cell-based bone regeneration therapies.

Engineered stromal vascular fraction for tissue regeneration

The treatment of various tissue injuries presents significant challenges, particularly in the reconstruction of large and severe tissue defects, with conventional clinical methods often yielding suboptimal results. However, advances in engineering materials have introduced new possibilities for tissue repair. Bioactive components are commonly integrated with synthetic materials to enhance tissue reconstruction. Stromal vascular fraction (SVF), an adipose-derived cell cluster, has shown considerable potential in tissue regeneration due to its simple and efficient way of obtaining and its richness in growth factors. Therefore, this review illustrated the preparation, characterization, mechanism of action, and applications of engineered SVF in various tissue repair processes, to provide some references for the option of better methods for tissue defect reconstruction.

Effect of injecting adipose stem cells combined with platelet-rich fibrin releasate at Shenshu acupoint (BL23) on acute kidney injury in rabbits

Introduction

Acute kidney injury (AKI) is a major and unmet medical need, characterized by a sudden onset of kidney dysfunction that often occurs within 7 days. Adipose-derived stem cells (ADSCs) are known for their regenerative, differentiative, and repair abilities, making them a promising therapeutic option for kidney injury. Platelet-rich fibrin releasate (PRFr), derived from platelet-rich fibrin after static incubation, contains numerous growth factors that may promote the differentiation and proliferation of stem cells. Additionally, acupoints such as Shenshu (BL23) have been used in clinical practice and experimental settings, particularly in renal failure treatments.

Methods

This study aimed to evaluate the synergistic effects of ADSCs and PRFr, administered separately or in combination, at the Shenshu acupoint (BL23) in New Zealand white rabbits with acute kidney injury. The treatment groups were injected with ADSCs, PRFr, or a combination of both. Serum creatinine (CRE) and blood urea nitrogen (BUN) levels were measured to assess kidney function. Additionally, histological examination of kidney tissue was performed to observe morphological changes and tissue repair.

Results

The PRFr + ADSCs treatment group exhibited a significant reduction in CRE and BUN levels during the second week following transplantation. After 7 weeks of treatment, the PRFr + ADSCs group showed the most favorable kidney repair outcomes, with intact glomeruli, no edema or vacuole-like changes in the renal tubular epithelial cells, and no significant infiltration of inflammatory cells in the surrounding tissues.

Discussion

The administration of PRFr, ADSCs, and their combination at the Shenshu acupoint (BL23) demonstrated a potential therapeutic effect in repairing damaged renal cells, improving kidney function, and reducing serum CRE and BUN levels. These findings suggest that injection of PRFr, ADSCs, and their combination at the Shenshu acupoint (BL23) can effectively repair damaged renal cells and improve kidney function in AKI. The observed synergistic effect indicates that this approach holds potential as a novel therapeutic strategy for kidney injury. Further research is needed to optimize treatment protocols and elucidate the underlying mechanisms.

Stem Cell Therapies in Canine Cardiology: Comparative Efficacy, Emerging Trends, and Clinical Integration

Cardiovascular diseases are a leading cause of morbidity and mortality in dogs, with limited options available for reversing myocardial damage. Stem cell therapies have shown significant potential for cardiac repair, owing to their immunomodulatory, antifibrotic, and regenerative properties. This review evaluates the therapeutic applications of mesenchymal stem cells (MSCs) derived from bone marrow, adipose tissue, and Wharton's jelly with a focus on their role in canine cardiology and their immunoregulatory properties. Preclinical studies have highlighted their efficacy in enhancing cardiac function, reducing fibrosis, and promoting angiogenesis. Various delivery methods, including intracoronary and intramyocardial injections, are assessed for their safety and efficacy. Challenges such as low cell retention, differentiation efficiency, and variability in therapeutic responses are also discussed. Emerging strategies, including genetic modifications and combination therapies, aim to enhance the efficacy of MSCs. Additionally, advances in delivery systems and regulatory frameworks are reviewed to support clinical translation. This comprehensive evaluation underscores the potential of stem cell therapies to revolutionize canine cardiovascular disease management while identifying critical areas for future research and clinical integration.

Efficacy and Safety of Cell-Assisted Acellular Adipose Matrix Transfer for Volume Retention and Regeneration Compared to Hyaluronic Acid Filler Injection

BACKGROUND

Cell-assisted acellular adipose matrix (AAM) transfer is a novel technique for soft tissue volume restoration, where AAM acts as a scaffold for tissue proliferation and promotes host cell migration, vascularization, and adipogenesis. This study aimed to evaluate the efficacy and safety of in vivo cell-assisted AAM transfer compared to hyaluronic acid (HA) filler injection.

METHODS

Human adipose tissue was used to manufacture AAM, and murine adipose-derived stem cells (ASCs) were prepared. Nude mice were divided into four groups: AAM transfer (AT), ASC-assisted AAM transfer (CAT), HA filler injection (HI), and ASC-assisted HA filler injection (CHI). Eight weeks post-transfer, in vivo graft volume/weight, histology, and gene expression were analyzed to assess efficacy and safety.

RESULTS

The AAM retained its three-dimensional scaffold structure without cellular components. AT/CAT showed lower volume retention than HA/CHA; however, CAT maintained a similar volume to HA. Histologically, adipogenesis and collagen formation were increased in AT/CAT compared to HA/CHA, with CAT showing the highest levels. CAT also demonstrated superior angiogenesis, adipogenesis, and gene expression (Vegf and Pparg), along with lower Il-6 expression, higher Il-10 expression, and reduced capsule formation, indicating better biocompatibility.

CONCLUSIONS

Cell-assisted AAM transfer is a promising technique for volume retention and tissue regeneration, offering a safe and effective alternative to HA filler injections.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Mechanisms and aetiology-dependent treatment of acute liver failure

This review compiles the mechanisms of acute liver failure (ALF) as well as the current and potential therapeutic approaches, including aetiology-specific treatment, and the issues encountered with such approaches. On a cellular level, ALF is characterized by massive hepatocyte death due to different types of cellular demise. Compensatory hyperplasia and functional recovery are possible when the regenerative capacity is sufficient to sustain hepatic function. ALF has a high mortality of about 30% and can lead to death in a very short time despite maximum therapeutic intervention. Besides aetiology-specific therapy and intensive care, the therapeutic option of emergency liver transplantation has significantly improved the prognosis of patients with ALF. However, due to limiting factors such as organ shortage, many patients die on the waiting list. In addition to graft assessment, machine perfusion may have the potential to recondition marginal organs and thus expand the organ donor pool.

Characteristics of the Dynamic Evolutionary Pathway of ADSCs Induced Differentiation into Astrocytes Based on scRNA-Seq Analysis

We employed single-cell transcriptome sequencing to reveal the dynamic gene expression changes during the differentiation of adipose-derived stromal cells (ADSCs) into astrocytes. Single-cell RNA sequencing was conducted on cells from the ADSCs group and the induced groups at 2, 7, 14, and 21 days using the 10 × Chromium platform. Data underwent quality control and dimensionality reduction. Cell differentiation trajectories were constructed using Monocle2, and differentially expressed genes (DEGs) in each cell cluster were identified using differential selection algorithms. DEGs at each time point were annotated using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), and regulatory intensities of transcription factors were analyzed using SCENIC. Integrating all groups, a total of five samples were divided into 13 cell clusters (0-12 clusters). DEGs between clusters and those compared with ADSCs at various induced time points showed distinct specificities. Monocle2 constructed cell differentiation trajectories; ADSCs can differentiate into mature astrocytes not only through the direct pathway from the 1 branch to the 3 branch but also through an indirect pathway, involving the 1 branch to the 2 branch before progressing to the 3 branch. SCENIC analysis highlighted the critical regulatory roles of STAT1, MYEF2, and SOX6 transcription factors during the differentiation of ADSCs into astrocytes. ADSCs can differentiate into mature astrocytes through two distinct pathways: direct and indirect. By the 14th day of induction, mature astrocytes have formed, characterized by a cell cycle arrest in mitosis. Further induction leads to degenerative senescence changes in differentiated cells.

Establishment of a mouse organ culture model of fetal cleft lip for the evaluation of adipose-derived stem cell therapy

Introduction

Cleft lip and cleft palate are congenital disorders resulting from abnormal facial development. Current treatments require multiple surgeries, which have risks of scar formation and facial deformities. Recently, fetal treatments utilizing "scarless healing" have gained attention, as early intervention shows potential to suppress scarring. In the field of regenerative medicine, mesenchymal stem cell therapies using cell sheets have advanced, by which promotion of tissue repair is expected. However, researches for fetal treatment using small animal models of cleft lip are challenging due to the high fetal mortality caused by surgical invasiveness. Although organ culture methods may offer an alternative approach, no organ culture system for fetal cleft lip research has been reported.

Methods

In this study, a cleft lip was surgically created on the upper left side lip of E15.5 mouse fetuses. These fetuses were cultured for four days using an organ culture system. Histological evaluation was performed to evaluate cell density, tissue morphology, and epithelialization. Additionally, adipose-derived stem cell (ADSC) sheets were transplanted two days after cleft lip creation to evaluate their effect on tissue repair.

Results

The histological analysis showed that cell density and tissue morphology were stably maintained in the four-day culture period. Epithelialization of the incision site was observed two days after surgery, confirming the completion of cleft formation. In the ADSC-transplanted group, epithelialization of the cleft site was observed, which indicates that the stem cell sheets contributed to tissue repair.

Conclusion

This research demonstrates the successful development of a cleft lip organ culture model and highlights the potential of ADSC sheets in promoting tissue repair. These findings provide a foundation for future regenerative medicine strategies in fetal cleft lip therapy.

Micro-fragmented adipose tissue-An innovative therapeutic approach: A narrative review

Subcutaneous adipose tissue provides distinct advantages as a source of mesenchymal stem cells due to its accessibility and the ease of isolating stem cells. Human adipose stem cells, located in the stromal-vascular fraction, can be harvested using mechanical methods to produce microfragmented adipose tissue (MFAT). Local injections of MFAT have shown potential in promoting natural tissue regeneration. This review introduces the concept of MFAT, highlights its clinical applications, and explores its potential in regenerative medicine, offering insights into its role as an innovative therapeutic approach.

Unveiling distinctions between mesenchymal stromal cells and stem cells by single-cell transcriptomic analysis

Mesenchymal stromal cells (MSCs) and stem cells are distinct types of cells, but they are practically undistinguishable by currently commonly-used identification markers. A single-cell transcriptomic analysis was used to solve this problem. There are eight critical genes involved in self-renewal and differentiation, SOX2, NANOG, POU5F1, SFRP2, DPPA4, SALL4, ZFP42 and MYCN expressed in ESCs, iPSCs and adult stem cells (ASCs), but not in MSCs. There are five functional genes of MSCs, TMEM119, FBLN5, KCNK2, CLDN11 and DKK1, which are not expressed in stem cells. Trajectory analysis displayed clear developmental cliffs from ESCs/iPSCs to ASCs and to MSCs. Adipose-derived MSCs, relative to other types of MSCs, exhibit a more consistent and broader spectrum of gene expression for regulatory and excrete function. This study identifies distinction markers between MSCs and stem cells, providing an alternative approach for quality control of MSCs in their propagation and further mechanistic insights into their action.

Therapeutic Potential of Adipose-Derived Regenerative Cells for Ischemic Diseases

Adipose-derived regenerative cells (ADRCs) are one of the most promising cell sources that possess significant therapeutic effects. They have now become a main source of cell therapy for the treatment of ischemic diseases due to their easy accessibility, expansion, and differentiation. Additionally, ADRCs can release multiple paracrine factors and extracellular vesicles that contribute to tissue regeneration by promoting angiogenesis, regulating inflammation, alleviating apoptosis, and inhibiting fibrosis. However, ADRCs still have some limitations to realize their full therapeutic potential. To address these issues, protective mechanistic studies and bioengineering studies have been carried out. This review focused on the recently studied mechanisms, such as paracrine factors, cell fusion, and mitochondrial transfer, involving the therapeutic potential of ADRCs in ischemic diseases and discussed some modification techniques of ADRCs.

Application of multi-needle injector for delivering human adipose stem cells to combat photoaging in nude mice

To assess the efficacy of human adipose stem cells(ADSCs) in treating photo-aged skin using multi-needle injector versus syringe injection methods. Mice were divided into three groups: blank, model, and experimental. Skin photoaging was induced by eight weeks of UVB irradiation in the model and experimental groups. ADSCs (1 × 106 cells/120µL) were injected into the experimental group mice thrice over a 30-day period, using a syringe on one side and a multi-needle injector on the other side of the nude mice dorsum. Follow-up assessments one month post-injection included high-definition photography for wrinkle and needle mark analysis, histological evaluation of dermal thickness, collagen and elastic fibers. CD31 and Type I collagen levels were analyzed by immunohistochemistry, while MDA and SOD levels were assessed by ELISA assays. Post-UVB irradiation, significant photoaging signs were observed in the mice, including wrinkles and disordered collagen and elastic fibers. ADSCs treatment led to epidermal thinning, dermal collagen thickening, and improved collagen and elastic fiber organization. CD31 and Type I collagen expression increased, while MDA decreased, and SOD significantly increased. No significant differences were found between the injection methods. Multi-needle injector marks disappeared within 24 h, contrasting with syringe marks, and mass formation was reduced compared to syringe injections. ADSCs effectively ameliorate photoaging in mice. Multi-needle injector injections match the efficacy of syringe injections and offer advantages such as precise depth control and reduced mass formation, suggesting its potential as an effective tool for stem cell-based anti-aging treatments.

Growth factors IGF-1 and KGF and adipose-derived stem cells promote migration and viability of primary human keratinocytes in an in vitro wound model

Introduction

In the field of plastic surgery, epidermal transplantation is a potential treatment for chronic wounds that results in only minor donor site morbidity. Improving the regenerative capacities of epidermal grafts or single-cell suspensions and therefore accelerating healing processes would be of significant interest.

Methods

In the present study, we analyzed the effects of growth factors and adipose-derived stem cells (ADSCs) on keratinocyte properties. For optimum translation into the clinical setting, primary human keratinocytes and patient-matched ADSCs were isolated and used in an in vitro wound model.

Results

The keratinocyte migration and viability increased after treatment with the growth factors insulin-like growth factor 1 (IGF-1) and keratinocyte growth factor (KGF). A similar effect was observed with the use of a concentrated ADSC-conditioned medium (ADSC-CM). It was further possible to isolate the keratinocytes in a xenogen-free medium, which is essential for clinical translation. Importantly, a patient-dependent influence on the effects of the growth factors and ADSC-CM was observed.

Discussion

This study provides potential for the improvement of epidermal transplantation in the treatment of chronic wounds using xenogen-free isolated and cultivated keratinocytes, growth factors, and ADSC. Translating these results into clinical application may help accelerate wound healing and shorten the time until patients can return to everyday life.

Induced mesenchymal stem cells generated from periodontal ligament fibroblast for regenerative therapy

Bone fractures and bone loss represent significant global health challenges, with their incidence rising due to an aging population. Despite autologous bone grafts remain the gold standard for treatment, challenges such as limited bone availability, immune reactions, and the risk of infectious disease transmission have driven the search for alternative cell-based therapies for bone regeneration. Stem cells derived from oral tissues and umbilical cord mesenchymal stem cells (MSCs) have shown potential in both preclinical and clinical studies for bone tissue regeneration. However, their limited differentiation capacity and wound healing abilities necessitate the exploration of alternative cell sources. In this study, we generated induced pluripotent stem cells (iPSCs) using a safe, nonviral and mRNA-based approach from human periodontal ligament fibroblasts (PDLF), an easily accessible cell source. These iPSCs were subsequently differentiated into MSCs, referred to as induced MSCs (iMSCs). The resulting iMSCs were homogeneous, highly proliferative, and possessed anti-inflammatory properties, suggesting their potential as a superior alternative to traditional MSCs for regenerative therapy. These iMSCs demonstrated trilineage differentiation potential, giving rise to osteocytes, chondrocytes, and adipocytes. The iMSC-derived osteocytes (iOSTs) were homogeneous, patient-specific and showed excellent attachment and growth on commercial collagen-based membranes, highlighting their suitability for bone tissue regeneration applications. Given their promising characteristics compared to traditional MSCs, PDLF-derived iMSCs are strong candidates for future clinical studies in bone regeneration and other regenerative dental therapies.

Targeting Cytokines: Evaluating the Potential of Mesenchymal Stem Cell Derived Extracellular Vesicles in the Management of COVID-19

The Coronavirus Disease 2019 (COVID-19), caused by virus SARS-CoV-2, is characterized by massive inflammation and immune system imbalance. Despite the implementation of vaccination protocols, the accessibility of treatment remains uneven. Furthermore, the persistent threat of new variants underscores the urgent need for expanded research into therapeutic options for SARS-CoV-2. Mesenchymal stem cells (MSCs) are known for their immunomodulatory potential through the release of molecules into the extracellular space, either as soluble elements or carried by extracellular vesicles (EVs). The aim of this study was to evaluate the anti-inflammatory potential of EVs obtained from human adipose tissue (ASC-EVs) against SARS-CoV-2 infection. ASC-EVs were purified by size-exclusion chromatography, and co-culture assays confirmed that ASC-EVs were internalized by human lung cells and could colocalize with SARS-CoV-2 into early and late endosomes. To determine the functionality of ASC-EVs, lung cells were infected with SARS-CoV-2 in the presence of increasing concentrations of ASC-EVs, and the release of cytokines, chemokines and viruses were measured. While SARS-CoV-2 replication was significantly reduced only at the highest concentrations tested, multiplex analysis highlighted that lower concentrations of ASC-EV sufficed to prevent the production of immune modulators. Importantly, ASC-EVs did not contain detectable inflammatory cytokines, nor did they trigger inflammatory mediators, nor affect cellular viability. In conclusion, this work suggests that ASC-EVs have the potential to attenuate inflammation by decreasing the production of pro-inflammatory cytokines in lung cells following SARS-CoV-2 infection.

Optimal Strategies for Autologous Fat Grafting in Breast Augmentation and Reconstruction: A Systematic Review and Network Meta-Analysis

BACKGROUND

Cell-assisted lipotransfer (CAL) and platelet-rich plasma (PRP)-assisted lipotransfer have been used to overcome the low survival rate of conventional lipotransfer. However, there is still insufficient evidence to determine which technique is the best strategy for autologous fat grafting in breast cosmetic and reconstructive surgery. The present study aimed to compare the efficacy of traditional fat transplantation, CAL, and PRP-assisted lipotransfer.

METHODS

A systematic search was conducted in several databases, including PubMed, Web of Science, Cochrane, ClinicalTrials.gov, and Embase, concluding on January 21, 2024, to identify studies that met the inclusion criteria. Twelve studies were included after a rigorous selection process based on predefined criteria. Statistical analyses were conducted using R version 4.0.5 software with the netmeta and dmetar packages, utilizing a frequentist approach with a random-effects model. A network meta-analysis was performed to compare different fat graft procedures with regard to fat survival rate and complication events.

RESULTS

CAL and PRP-assisted lipotransfer were better than traditional fat grafting in terms of fat survival rate. In addition, there was no significant difference in the incidence of postoperative complications among the CAL, PRP, and traditional groups.

CONCLUSIONS

Given the results of network meta-analysis, it appears that both CAL and PRP-assisted lipotransfer have a higher fat survival rate for autologous fat grafting in breast augmentation and reconstruction. However, the transplantation strategy still needs to be analyzed based on actual conditions in clinical applications.

State of the Art in the Standardization of Stromal Vascular Fraction Processing

Stromal Vascular Fraction (SVF) has gained significant attention in clinical applications due to its regenerative and anti-inflammatory properties. Initially identified decades ago, SVF is derived from adipose tissue and has been increasingly utilized in a variety of therapeutic settings. The isolation and processing protocols for SVF have evolved substantially, particularly after its classification as an Advanced Therapy Medicinal Product (ATMP), which mandates adherence to Good Manufacturing Practices to ensure sterility and product quality. Despite the progress, few studies over the last decade have focused on the standardization of SVF processing. Recent advances, driven by the potential of SVF and its derived products such as Adipose-derived Stem Cells, have prompted the development of improved isolation strategies aimed at enhancing their therapeutic and regenerative efficacy. Notable progress includes the advent of automated processing systems, which reduce technical errors, minimize variability, and improve reproducibility across laboratories. These developments, along with the establishment of more precise protocols and guidelines, have enhanced the consistency and clinical applicability of SVF-based therapies. This review discusses the key aspects of SVF isolation and processing, highlighting the efforts to standardize the procedure and ensure the reliability of SVF products for clinical use.

Regional Gene Therapy for Bone Tissue Engineering: A Current Concepts Review

The management of segmental bone defects presents a complex reconstruction challenge for orthopedic surgeons. Current treatment options are limited by efficacy across the spectrum of injury, morbidity, and cost. Regional gene therapy is a promising tissue engineering strategy for bone repair, as it allows for local implantation of nucleic acids or genetically modified cells to direct specific protein expression. In cell-based gene therapy approaches, a variety of different cell types have been described including mesenchymal stem cells (MSCs) derived from multiple sources-bone marrow, adipose, skeletal muscle, and umbilical cord tissue, among others. MSCs, in particular, have been well studied, as they serve as a source of osteoprogenitor cells in addition to providing a vehicle for transgene delivery. Furthermore, MSCs possess immunomodulatory properties, which may support the development of an allogeneic "off-the-shelf" gene therapy product. Identifying an optimal cell type is paramount to the successful clinical translation of cell-based gene therapy approaches. Here, we review current strategies for the management of segmental bone loss in orthopedic surgery, including bone grafting, bone graft substitutes, and operative techniques. We also highlight regional gene therapy as a tissue engineering strategy for bone repair, with a focus on cell types and cell sources suitable for this application.

Traumatic brain Injury: Comprehensive overview from pathophysiology to Mesenchymal stem Cell-Based therapies

Traumatic brain injury (TBI) is a disastrous phenomenon which is considered to cause high mortality and morbidity rate. Regarding the importance of TBI due to its prevalence and its effects on the brain and other organs, finding new therapeutic methods and improvement of conventional therapies seems to be vital. TBI involves a complex physiological mechanism, with inflammation being a key component among various contributing factors. After incidence of TBI, inflammation can act as a double-edged sword in the process. Inflammation actually plays its role both as initiator and progressive index during TBI which can accumulate myeloid and lymphoid immune cells and trigger cell death pathways. Through this study we made this concept bold that that besides conventional therapies that could be used for traumatic brain injury, treatments based on mesenchyme stem cells (MSCs) and their derivatives including secretomes and exosomes demonstrate more efficacies particularly in preventing secondary injuries caused by TBI. Of note, we highlighted the valuable features of MSC-based therapies such as self-direction toward inflamed tissues and amplifying neuro-regenerative aspects. We listed possible challenges in the way of reaching this therapy to clinic to provide a clear and updated of the field.

Aspirin Inhibits the In Vitro Adipogenic Differentiation of Human Adipose Tissue-Derived Stem Cells in a Dose-Dependent Manner

Aspirin (ASA) is one of the most used medications worldwide and has shown various effects on cellular processes, including stem cell differentiation. However, the effect of ASA on adipogenesis of adipose tissue-derived stem cells (ASCs) remains largely unknown. Considering the potential application of ASCs in regenerative medicine and cell-based therapies, this study investigates the effects of ASA on adipogenic differentiation in human ASCs. ASCs were exposed to varying concentrations of ASA (0 µM, 400 µM, and 1000 µM) and evaluated for changes in morphology, migration, and adipogenic differentiation. While ASA exposure did not affect self-renewal potential, migration ability, or cell morphology, it significantly reduced lipid vacuole formation at 1000 µM after 21 days of adipogenic differentiation (p = 0.0025). This visible inhibition correlated with decreased expression of adipogenic markers (PPARG, ADIPOQ, and FABP4) and the proliferation marker MKi67 under ASA exposure in comparison to the control (ns). Overall, the findings demonstrate that ASA inhibits adipogenic differentiation of human ASCs in a dose-dependent manner in vitro, contrasting its known role in promoting osteogenic differentiation. This research highlights ASA's complex effects on ASCs and emphasizes the need for further investigation into its mechanisms and potential therapeutic applications in obesity and metabolic diseases. The inhibitory effects of ASA on adipogenesis should be considered in cell-based therapies using ASCs.

The Effect of Adipose-Derived Stem Cell (ADSC)-Exos on the Healing of Autologous Skin Grafts in Miniature Pigs

The skin functions as the body's primary defense barrier; when compromised, it can lead to dehydration, infection, shock, or potentially life-threatening conditions. Miniature pigs exhibit skin characteristics and healing processes highly analogous to humans. Mesenchymal stem cells contribute to skin injury repair through a paracrine mechanism involving exosomes. This research examines whether adipose-derived MSC exosomes effectively enhance healing following autologous skin grafting in miniature pigs. It also compares the roles and distinctions of ADSCs and ADSC-Exos in inflammatory responses and tissue regeneration. This study found significantly reduced levels of oxidative stress products and pro-inflammatory factors, while antioxidant factors, anti-inflammatory factors, and pro-regenerative factors were elevated, and anti-regenerative factor levels decreased. Moreover, the expression levels of key markers-namely, PI3K, Akt, and mTOR-in the regeneration-associated signaling pathway were increased. The alterations in these indicators indicate that ADSC-Exos can regulate inflammatory responses and promote regeneration. This study provides a novel theoretical foundation for the implementation of acellular therapy in clinical settings.

Integrative single-cell RNA-seq and ATAC-seq analysis of the evolutionary trajectory features of adipose-derived stem cells induced into astrocytes

This study employs single-cell RNA sequencing (scRNA-seq) and assay for transposase-accessible chromatin with high-throughput sequencing technologies (scATAC-seq) to perform joint sequencing on cells at various time points during the induction of adipose-derived stem cells (ADSCs) into astrocytes. We applied bioinformatics approaches to investigate the differentiation trajectories of ADSCs during their induced differentiation into astrocytes. Pseudotemporal analysis was used to infer differentiation trajectories. Additionally, we assessed chromatin accessibility patterns during the differentiation process. Key transcription factors driving the differentiation of ADSCs into astrocytes were identified using motif and footprint methods. Our analysis revealed significant shifts in gene expression during the induction process, with astrocyte-related genes upregulated and stem cell-related genes downregulated. ADSCs first differentiated into neural stem cell-like cells with high plasticity, which further matured into astrocytes via two distinct pathways. Marked changes in chromatin accessibility were observed during ADSC-induced differentiation, affecting transcription regulation and cell function. Transcription factors analysis identified NFIA/B/C/X and CEBPA/B/D as key regulators in ADSCs differentiation into astrocytes. We observed a correlation between chromatin accessibility and gene expression, with ADSCs exhibiting broad chromatin accessibility prior to lineage commitment, where chromatin opening precedes transcription initiation. In summary, we found that ADSCs first enter a neural stem cell-like state before differentiating into astrocytes. ADSCs also display extensive chromatin accessibility prior to astrocyte differentiation, although transcription has not yet been initiated. These findings offer a theoretical framework for understanding the molecular mechanisms underlying this process.

Isolation of Stromal Vascular Fraction by Fractionation of Adipose Tissue

Adipose tissue-derived stromal cells (ASCs) are promising candidates for cellular therapy in the field of regenerative medicine. ASCs are multipotent mesenchymal stem cell-like and reside in the stromal vascular fraction (SVF) of adipose tissue with the capacity to secrete a plethora of pro-regenerative growth factors. Future applications of ASCs may be restricted through (trans)national governmental policies that do not allow for use of non-human-derived (non-autologous) enzymes to isolate ASC. Besides, enzymatic isolation procedures are also time-consuming. To overcome this issue, non-enzymatic isolation procedures to isolate ASCs or the SVF have been developed, such as the fractionation of adipose tissue procedure (FAT). This standardized procedure to isolate the stromal vascular fraction can be performed within 10-12 min. The short procedure time allows for intra-operative isolation of 1 mL of stromal vascular fraction derived from 10 mL of centrifuged adipose tissue. The stromal vascular fraction mostly contains blood vessels, extracellular matrix, and ASCs. However, based on the histological stainings, an interdonor variation exists which might result in different therapeutic effects. The existing interdonor variations can be addressed by histological stainings and flow cytometry. Furthermore, the re-usable open system has been replaced by a validated disposable semi-closed system with a one-hole fractionator.