An Update on Adipose-Derived Stem Cells for Regenerative Medicine: Where Challenge Meets Opportunity

Regulation of osteoimmune microenvironment via functional dynamic hydrogel for diabetic bone regeneration

Bone regeneration and repair face formidable challenges under diabetic conditions, primarily due to the disruption of macrophage polarization induced by diabetes and the inflammatory imbalance within the bone microenvironment. We have developed a novel dynamic hydrogel system (AG-CD@LINA), constructed through the coordination crosslinking of thiolated gelatin (SH-Gelatin) and gold ions (Au3+), followed by grafting with cyclodextrin to load the ligand linagliptin. This hydrogel effectively inhibits the formation of M1 macrophages and the expression of pro-inflammatory cytokines by gradually releasing linagliptin. Simultaneously, it promotes the formation of M2 macrophages and the expression of anti-inflammatory cytokines, thus improving the inflammatory microenvironment of diabetic bone defects. Consequently, it facilitates the migration of mesenchymal stem cells and angiogenic cells, augments osteogenic activity, and promotes vascularization, collectively accelerating the regeneration of diabetic bone tissue. Mechanistically, polarization occurs through the TLR3-NF-κB signaling pathway. In vivo experiments demonstrate that the in-situ injection of the hydrogel enhances the regeneration of bone tissue and the restoration of bone structure in diabetic bone defects, effectively modulating local inflammation and promoting vascular formation. This study suggests that functionalized dynamic hydrogels can improve the inflammatory microenvironment by regulating in situ macrophage polarization, thereby facilitating the reconstruction of bone microstructure. This approach represents a promising novel therapeutic strategy for diabetic bone defects.

Bridging the gap: clinical translation of adipose-derived stem cells - a scoping review of clinical trials

BACKGROUND

Adipose-derived stem cells (ADSCs) have emerged as a promising therapeutic tool in regenerative medicine due to their multipotency, immunomodulatory properties, and ease of procurement. Despite extensive preclinical research, the clinical translation of ADSCs remains fragmented, with challenges in standardization, reproducibility, and evidence synthesis.

OBJECTIVE

This scoping review, complemented by bibliometric analysis, aims to map the landscape of randomized controlled trials (RCTs) evaluating ADSC therapies, identify gaps between basic research and clinical translation, and highlight emerging trends in the field.

METHODS

A systematic search of Web of Science, PubMed, Embase, ClinicalTrials.gov, EudraCT, and ChiCTR database (2009-2025) identified 82 RCTs. Bibliometric analysis of preclinical studies was conducted using VoSviewer to visualize keyword clusters and temporal trends. Data on trial characteristics, endpoints, and translational challenges were extracted and synthesized.

RESULTS

The 82 included RCTs spanned 17 medical specialties, with orthopedics (26.8%), dermatology (14.6%), and neurology (9.7%) being the most studied. Spain (21.95%) and China (18.29%) and the USA (15.85%) led trial numbers, but 97% were single-country studies with a median sample size of 40. Primary endpoints trends from safety to efficacy. Bibliometric analysis revealed three clusters: stem cell sources and basic biology, orthopedic applications, and tissue regeneration mechanisms. Key gaps included protocol heterogeneity (e.g., isolation methods, cryopreservation variability), regulatory fragmentation, limited long-term follow-up, and inconsistent clinical outcomes, particularly in neurology. Emerging trends highlighted the therapeutic potential of stromal vascular fraction (SVF) and ADSC-derived exosomes.

CONCLUSIONS

While ADSCs demonstrate significant therapeutic potential, clinical translation is hindered by standardization deficits and mechanistic knowledge gaps. Future research should prioritize international collaboration, large-scale trials, and mechanistic studies to optimize ADSC therapies. Innovations in SVF and exosome-based treatments represent promising avenues for advancing regenerative medicine.

TRIAL REGISTRY

This scoping review was preregistered at OSF platform: https://doi.org/10.17605/OSF.IO/YKHW3 .

HAMA-SBMA hydrogel with anti-inflammatory properties delivers cartilage organoids, boosting cartilage regeneration

Cartilage tissue lacks blood supply, which limits its ability to self-repair. Cartilage organoid (CO) technology, which replicates the structure and function of cartilage, holds significant promise. However, it is essential to maintain cellular function and ensure secure fixation at the site of injury. Therefore, we loaded allogeneic bone marrow mesenchymal stem cells (BMSCs) onto decellularized extracellular matrix microparticles of porcine articular cartilage (CEP) to construct CO-CCO, which demonstrated characteristics of articular cartilage. Additionally, betaine sulfonate methacrylate (SBMA) was incorporated into hyaluronic acid methacrylate (HAMA) to synthesize a novel hydrogel, HAMA-SBMA (HS), characterized by its adhesive properties, promotion of chondrogenesis, and inhibition of inflammation. In Vivo studies revealed that the combination of HS and CCO (HS + CCO) exhibited excellent repair efficacy in both rat and sheep models of cartilage defects. Mechanistically, we found that HS + CCO promoted cartilage repair by activating the Frizzled-related protein (Frzb), which inhibited inflammatory factors and enhanced the expression of the adhesion factor integrin ɑ5β1. This strategy, which combines hydrogels and organoids, enhances cartilage repair, offering substantial potential for clinical applications in cartilage regeneration.

ZIC1 transcription factor overexpression in segmental bone defects is associated with brown adipogenic and osteogenic differentiation

Transcriptional factor regulation is central to the lineage commitment of stem/ progenitor cells. ZIC1 (ZIC family member 1) is a C2H2-type zinc finger transcription factor expressed during development, brown fat, and certain cancers. Previously, we observed that overexpression of ZIC1 induces osteogenic differentiation at the expense of white adipogenic differentiation. In the present study, the feasibility of ZIC1 overexpressed human progenitor cells in critical-sized bone defects was studied. To achieve this, human adipose stem/stromal cells with other without lentiviral ZIC1 overexpression were implanted in a femoral segmental defect model in NOD-SCIDγ mice. Results showed that ZIC1 overexpressed cells induced osteogenic differentiation by protein markers in a critical-sized femoral segment defect compared to empty lentiviral control, although bone union was not observed. The immunohistochemical evaluation showed that implantation of ZIC1 overexpression cells led to an increase in osteoblast antigen expression (RUNX2, OCN), activation of Hedgehog signaling (Patched1), and an increase in brown adipogenesis markers (ZIC1, EBF2). In contrast, no change in bone defect-associated vasculature was observed (CD31, Endomucin). Together, these data suggest that overexpression of the ZIC1 transcription factor in progenitor cells is associated with differentiation towards osteoblastic and brown adipogenic cell fates.

Biodegradable Cryo-Self-Assembled Silk Fibroin Sponge for Enzyme-Responsive Exosome Delivery to Enhance Tendon Regeneration

The utilization of biological therapeutic agents in the treatment of tendon injuries represents a promising avenue, with particular attention drawn to adipose mesenchymal stem-cell-derived exosomes (ADSCs-exos) owing to their pivotal role in regenerative medicine. Identifying a therapeutic strategy to prolong exosome retention at the injury site for effective tendon repair remains challenging. In this study, we explored the potential of ADSC-exosomes in vitro, demonstrating their ability to promote the behavior of tendon stem/progenitor cells (TSPCs). Additionally, we designed a fibroin (SF) sponge as a biodegradable platform for enzyme-responsive exosome delivery. Subsequently, we used biodegradable SF sponges to deliver ADSC exosomes into the patellar tendon defect in rats. The results showed that, in vivo, exosomes were gradually released from the SF sponges, remained in the defect area for an extended period, and exerted functional benefits locally. These findings were supported by the upregulation of tendon-associated protein expression and improved mechanical properties observed in the in vivo specimens. In summary, we substantiated the advantageous role of ADSCs-exos in facilitating tendon regeneration. Moreover, the utilization of a SF-exos sponge delivery system emerged as an efficacious local treatment strategy for exosome delivery. These findings hold promise for the future application of exosomes in innovative therapies tailored to address tendon injuries.

ADSC-derived exosomes mitigate radiation-induced skin injury by reducing oxidative stress, inflammation and cell death

Background

Radiation-induced skin injury (RISI) is a significant complication of radiotherapy and affects over 95% of patients who undergo radiation treatment. The pathophysiological cascade of RISI includes oxidative stress, persistent inflammation, and excessive fibrotic remodeling. Current treatments provide limited efficacy and primarily focusing on symptomatic relief. Exosomes from adipose-derived stem cells (ADSC-Exo) offer promising therapeutic effects on multiple types of skin injury, while their roles in the treatment of RISI remains to be fully explored.

Method

A mouse model of RISI and an in vitro radiation-induced cellular damage model were established to evaluate the therapeutic effects of ADSC-derived exosomes. ADSC-Exo were isolated via size-exclusion chromatography and characterized using TEM, NTA, and immunoblotting. H&E staining and Masson staining were used to evaluate the extent of skin radiation-induced skin damage and fibrosis. Skin immunofluorescence was performed to assess macrophage infiltration and polarization, while immunohistochemistry staining was conducted to determine the expression levels of inflammatory mediators in the skin samples. In the in vitro experiments, ROS probes were used to evaluate cellular oxidative stress levels, and western blot analysis was employed to detect the expression levels of apoptosis and pyroptosis related proteins.

Result

ADSC-Exo effectively alleviated radiation-induced skin injury and fibrosis, reduced macrophage infiltration, and promoted macrophage polarization toward the M2 phenotype. Additionally, ADSC-Exo decreased the expression levels of IL-1β and IL-6 in skin tissues after irradiation. In in vitro experiments, ADSC-Exo mitigated oxidative stress in irradiated mouse fibroblasts, and reduced the upregulation of apoptosis-related proteins BAX and CASPASE-3, as well as pyroptosis-related proteins GSDMD and CASPASE-1 after radiation exposure.

Conclusion

ADSC-Exo alleviated RISI through multifaceted effects, including macrophage polarization modulation, inflammation suppression, oxidative stress reduction, and inhibition of apoptosis and pyroptosis. These findings support the potential of ADSC-Exo as a promising cell-free therapy for RISI.

Porous Se@SiO2 nanoparticle composite hydrogels loaded with adipose stem cells improves the local microenvironment to promote rotator cuff tendon-bone healing in rats

Functional repair of the tendon-bone interface poses significant challenges in clinical practice; furthermore, identifying methods to enhance healing at enthesis is a central concern in regenerative medicine. The application of stem cells in the healing process of interface injuries is widespread; however, direct injection of stem cells into this interface leads to significant losses of many stem cells. Oxidative stress significantly influences interface repair, and the role of selenium in mitigating oxidative stress and regulating inflammation has been demonstrated. This study utilised gelatine methacrylate (GelMA) as a stem cell transporter, while porous Se@SiO2 nanoparticles (Se@SiO2 NPs) were incorporated to change the interface microenvironment and facilitate the repair of the tendon-bone interface. Oxidative stress effects were analysed using flow cytometry, immunofluorescence staining, and qRT-PCR. The repair of the enthesis was assessed using histological staining, biomechanical evaluation, and MRI. Se@SiO2 NPs significantly reduced the expression of inflammation-related markers in an in vitro oxidative stress model. Additionally, porous selenium nanocomposite hydrogels loaded with adipose stem cells were implanted into the rat tendon-bone interface. At eight weeks following the procedure, the enthesis exhibited superior collagen fibre continuity and orientation, enhanced bone and fibrocartilage production, and biomechanical functions that were substantially greater than those of the comparison group. This study demonstrates that porous Se@SiO2 NP composite hydrogels with antioxidant and anti-inflammatory properties provide a supportive environment for transplanted stem cells and promote tissue repair.

Roles for Exosomes from Various Cellular Sources in Spinal Cord Injury

Spinal cord injury (SCI) is a severe disorder characterized by regeneration challenges in the central nervous system (CNS), resulting in permanent paralysis, loss of sensation, and abnormal autonomic functions. The complex pathophysiology of SCI poses challenges to traditional treatments, highlighting the urgent need for novel treatment approaches. Exosomes have emerged as promising candidates for SCI therapy because of their ability to deliver a wide range of bioactive molecules, such as RNAs, proteins, and lipids, to target cells with minimal immunogenicity, which contribute to anti-inflammatory, anti-apoptotic, autophagic, angiogenic, neurogenic, and axon remodeling activities. In this study, we classified exosomes from different sources into four categories based on the characteristics of the donor cells (mesenchymal stem cells, neurogenic cells, immune cells, vascular-associated cells) and provided a detailed summary and discussion of the current research progress and future directions for each source. We also conducted an in-depth investigation into the applications of engineered exosomes in SCI therapy, focusing on their roles in drug delivery and combination with surface engineering technologies and tissue engineering strategies. Finally, the challenges and prospects of exosomal clinical applications in SCI repair are described.

Enhancing Tendon Regeneration: Investigating the Impact of Topography on the Secretome of Adipose-Derived Stem Cells

Tendons are vital for maintaining integrity and movement, but current treatment options are insufficient for their regeneration after injuries. Previous studies have shown that the secretome from mesenchymal stem cells (MSCs) promoted tendon regeneration. However, limited studies have explored the impact of the physical microenvironment on the secretome's efficacy of MSCs. In this study, it is shown that the topographic orientation regulates the secretome of human adipose-derived stem cells (ADSCs) and promotes tendon regeneration. Conditioned medium (CM) is collected from ADSCs cultured on the scaffolds with different topography. The results show that CM generated from aligned structure group has a potent effect in promoting cell migration and proliferation, tenogenic differentiation, macrophage polarization toward M2 phenotype, tendon structure and mechanical function recovery. Proteomic analysis revealed that the aligned structure can up-regulate the secretion of Extracellular matrix (ECM) proteins while down-regulate proinflammatory factors. This modulation activates the MAPK, GPCR and Integrin signaling pathways which may account for the enhanced effect on tendon regeneration. This study offers a promising and safer non-cell-based treatment option for tendon repair.

Adipose-derived stem cells enhance the tumorigenic potential of pre-malignant breast epithelial cells through paracrine activation of PI3K-AKT pathway

BACKGROUND

Adipose-derived stem cells (ADSCs)-assisted fat grafting has emerged as a widely used procedure for breast reconstruction post mastectomy and for aesthetic augmentation. Given the limited cases of breast cancer following grafting, the oncological safety of this procedure remains controversial.

METHODS

The effects of ADSCs on the oncogenic features of premalignant MCF-10AT cells were investigated using co-culture and xenograft models. We further evaluated the malignancy-promoting effect of ADSCs in a 7,12-Dimethylbenz(a)anthracene (DMBA)-induced breast cancer model. RNA-sequencing was performed on ADSCs, MCF-10AT cells, and ADSC-co-cultured MCF-10AT cells. Protein changes in ADSC/MCF-10AT co-culture medium and MCF-10AT cells were determined by proteomic analysis. Pathway inhibitors were used to investigate signaling pathways involved in the ADSC-induced oncogenic changes of MCF-10AT cells.

RESULTS

We found that ADSCs promoted the proliferation and migration of MCF-10AT cells, and co-injection of ADSCs increased the tumor incidence of MCF-10AT cells from 29% to 58% in nude mice. Additionally, grafted ADSCs significantly enhanced tumor incidence, growth, and distant metastasis in the DMBA-induced rats, while it could not induce tumorigenesis in normal breast tissues. Combined RNA-sequencing and proteomic analysis demonstrated that the paracrine factors secreted by ADSCs robustly activated the oncogenic PI3K-AKT signaling in MCF-10AT cells. We also revealed the auto-activated TGF-beta and Wnt pathways in co-cultured MCF-10AT cells, which may be synergistic in tumor formation and progression. As expected, blocking these pathways, especially the PI3K-AKT pathway, strongly diminished the promoting effects of ADSCs, suggesting their potential as therapeutic targets for ADSC grafting-associated breast tumors.

CONCLUSIONS

Our data illustrated the synergistic effect between ADSC paracrine factors and MCF-10AT auto-activated pathways in the carcinogenesis of MCF-10AT cells through activation of the oncogenic PI3K-AKT pathway. Based on these findings, we strongly recommend pre-operative examinations for breast cancer risk factors before ADSC-associated transplantation.

Intrauterine infusion of autologous endometrial stem cells for the treatment of moderate and severe intrauterine adhesions: a before-and-after study

BACKGROUND

Intrauterine adhesions (IUAs) can easily cause female infertility or recurrent abortion, but there is still no effective treatment to improve the pregnancy and live birth rates in patients with IUAs. In recent years, great advances have been made in stem cell therapy; however, additional clarity is needed on the clinical efficacy of endometrial stem cells in the treatment of IUAs.

MATERIALS AND METHODS

Fifteen patients with moderate-to-severe IUAs were included in the study at Xiangtan Central Hospital from 2018 to 2020. Patients were treated with endometrial stem cells and sodium hyaluronate gel by intrauterine perfusion in combination with estrogen and acetylsalicylic acid support therapy. Then, data on the pregnancy and live birth status was collected within two years after treatment. To explore the underlying mechanism, primary endometrial stem cells from healthy individuals and IUA patients, as well as fifth-generation endometrial stem cells from IUA patients, were further conducted with RNA sequencing to screen for differentially expressed genes, which were subsequently used for functional enrichment analysis.

RESULTS

After endometrial stem cell transplantation into the uterine cavity, the American Fertility Society scores of all patients decreased, and hysteroscopy revealed an improvement in the uterine condition and a reduction in adhesion symptoms. The total pregnancy rate of the 15 patients was 60.0% and the live birth rate was 53.3%. In addition, RNA sequencing analysis revealed that the cytokine - cytokine receptor interaction was associated with endometrial repair by endometrial stem cells.

CONCLUSIONS

Intrauterine infusion of autologous endometrial stem cells is highly effective for patients with moderate-to-severe IUA, and is a promising treatment strategy.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, CHICTR1800016769, Registered 22 June 2018- Retrospectively registered, https://www.chictr.org.cn/showproj.html?proj=27042 .

Biophysically Optimized Nanofiber-Hydrogel Scaffold Composite Acts as "Bio-Bonsai" for Peripheral Nerve Simulation and Regeneration via Orienting Adipose Derived Stem Cells into Schwann-Like Cell Differentiation

Efficient repairment of peripheral nerve injury (PNI) remains a severe clinical challenge worldwide, and recovering the regenerative capability of neurons in peripheral nervous system is hindered by the slow rate and inaccurate direction of axonal elongation. Schwann cells (SCs) loaded nerve guidance conduit has been proven to improve PNI repair, but the low cell survival rate and incomplete differentiation of SCs limited its practical application. To address these hurdles, a biophysically optimized nanofiber-hydrogel scaffold composite (APML@PC) is prepared in this study, the "bio"bonsai""inspired strategy integrates topological and biological cues to promote adipose-derived mesenchymal stem cells (ADSCs) adhesion, proliferation, and Schwann-like cell differentiation. In vitro and in vivo experiments confirmed the favorable biocompatibility and reasonable biodegradation behavior of this inducible platform, and the robust capability to promote axonal growth, remyelination regeneration, as well as nerve function recovery. This novel composite can serve as a promising candidate for the development of advanced stem cell-based peripheral nerve regeneration, thereby paving a new avenue for clinically effective PNI therapy.

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.

Electrical hydrogel: electrophysiological-based strategy for wound healing

Wound healing remains a significant challenge in clinical practice, driving ongoing exploration of innovative therapeutic approaches. In recent years, electrophysiological-based wound healing strategies have gained considerable attention. Specifically, electrical hydrogels combine the synergistic effects of electrical stimulation and hydrogel properties, offering a range of functional benefits for wound healing, including antibacterial activity, real-time wound monitoring, controlled drug release, and electrical treatment. Despite significant progress made in electrical hydrogel research for wound healing, there is a lack of comprehensive, systematic reviews summarizing this field. In this review, we survey the latest advancements in electrical hydrogel technology. After analyzing the mechanisms of electrical stimulation in promoting wound healing, we establish a novel classification framework for electrical hydrogels based on their operational principles. The review further provides an in-depth evaluation of the therapeutic efficacy of these hydrogels in various types of wounds. Finally, we propose future directions and challenges for the development of electrical hydrogels for wound healing.

Curculigoside is a Promising Osteoprotective Agent for Osteoporosis: Review

The prevention and treatment of osteoporosis (OP) is one of the major issues in coping with the aging population; however, there are limited treatments available for OP. In-depth study of OP pathogenesis and development of new therapeutic strategies has become an urgent medical need facing the aging society. Curculigoside is a natural product widely found in plants, which can modulate cellular differentiation and function in osteogenic cells and exert significant osteoprotective effects. In addition, curculigoside showed significant positive effects on the treatment of OP animal models. Specific mechanisms include inhibition of inflammatory responses, antagonism of oxidative stress, and modulation of various signaling. Therefore, we hypothesized that curculigoside could represent a novel therapeutic strategy for OP. This article reviews recent research advances in the treatment of OP with curculigoside, including the origin and basic characteristics of curculigoside, the mechanisms and therapeutic effects that may be involved in in vitro as well as in vivo studies. We also examine the pharmacokinetics of curculigoside and investigate modified uses that may augment its therapeutic efficacy. This article seeks to encourage additional investigation into curculigoside-based treatments for osteoporosis.

A Versatile Immune Protective Armor to Enhance the Regenerative Potential of Exogenous Stem Cells

Host immune rejection has long been recognized as a major contributor to the poor survival rates of exogenous stem cells (ESCs). In this study, we present a simple and versatile strategy to protect ESCs from host immune system insults by developing a protective "armor." This armor was designed using tannic acid (TA), leveraging its strong affinity for biomacromolecules and its anti-inflammatory properties. Prior to implantation, the armor can be readily applied to the surface of individual ESCs, cell aggregates, cell sheets, or cell-laden hydrogel systems by simply immersing them in a TA solution for several seconds, without additional processing steps. The TA-based armor effectively modulates the acute inflammatory response during the initial days postimplantation by scavenging reactive oxygen species (ROS), thereby creating an ESCs-friendly immune microenvironment. This was evidenced by reduction in the infiltration of pro-inflammatory immune cells and the secretion of pro-inflammatory cytokines. Consequently, the survival of engrafted ESCs was significantly enhanced, with preserved stemness and immunomodulatory functions. The regenerative potential of ESCs was further demonstrated in a rat periodontal defect model. These findings provide a novel approach for enhancing the regenerative performance of ESCs and offer a straightforward and versatile strategy to shield ESCs from host immune rejection.

Migrasomes as intercellular messengers: potential in the pathological mechanism, diagnosis and treatment of clinical diseases

Migrasomes are newly identified organelles that were first discovered in 2015. Since then, their biological structure, formation process, and physiological functions have been gradually elucidated. Research in recent years has expanded our understanding of these aspects, highlighting their significance in various physiological and pathological processes. Migrasomes have been found to play crucial roles in normal physiological functions, including embryonic development, vascular homeostasis, material transport, and mitochondrial quality control. Additionally, emerging evidence suggests their involvement in various diseases; however, clinical research on their roles remains limited. Current studies indicate that migrasomes may contribute to disease pathogenesis and hold potential for diagnostic and therapeutic applications. This review consolidates existing clinical research on migrasomes, focusing on their role in disease mechanisms and their use in medical applications. By examining their biological structure and function, this review aims to generate insights that encourage further research, ultimately contributing to advancements in disease prevention and treatment.

The Application of Stem Cells and Exosomes in Promoting Nerve Conduits for Peripheral Nerve Repair

The repair of peripheral nerve injury (PNI) presents a multifaceted and protracted challenge, with current therapeutic approaches failing to achieve optimal repair outcomes, thereby not satisfying the considerable clinical demand. The advent of tissue engineering has led to a growing body of experimental evidence indicating that the synergistic application of nerve conduits, which provide structural guidance, alongside the biological signals derived from exosomes and stem cells, yields superior therapeutic results for PNI compared to isolated interventions. This combined approach holds great promise for clinical application. In this review, we present the latest advancements in the treatment of PNI through the integration of stem cells or exosomes with nerve conduits. We have addressed the inadequate efficiency of exosomes or stem cells in conjunction with nerve conduits from 3 perspectives: enhancing stem cells or exosomes, improving nerve conduits, and incorporating physical stimulation.

CircAars-Engineered ADSCs Facilitate Maxillofacial Bone Defects Repair Via Synergistic Capability of Osteogenic Differentiation, Macrophage Polarization and Angiogenesis

Adipose-derived stem cells (ADSCs) hold significant promise in bone tissue engineering due to their self-renewal capacity and easy accessibility. However, their limited osteogenic potential remains a critical challenge for clinical application in bone repair. Emerging evidence suggests that circular RNAs (circRNAs) play a key role in regulating stem cell fate and osteogenesis. Despite this, the specific mechanisms by which circRNAs influence ADSCs in the context of bone tissue engineering are largely unexplored. This study introduces a novel strategy utilizing circAars, a specific circRNA, to modify ADSCs, which are then incorporated into gelatin methacryloyl (GelMA) hydrogels for the repair of critical-sized maxillofacial bone defects. The findings reveal that circAars predominantly localizes in the cytoplasm of ADSCs, where it acts as a competitive sponge for miR-128-3p, enhancing the osteogenic differentiation and migration capabilities of ADSCs. Furthermore, circAars-engineered ADSCs facilitate macrophage polarization from the M1 to M2 phenotype and enhance endothelial cell (EC) angiogenic potential through a paracrine mechanism. Additionally, GelMA scaffolds loaded with circAars-engineered ADSCs accelerate the repair of critical-sized maxillofacial bone defects by synergistically promoting osteogenesis, macrophage M2 polarization, and angiogenesis. This approach offers a promising therapeutic strategy for the treatment of critical-sized maxillofacial defects.

Light-based multi-material bioprinting of vascularised adipose tissue for breast fatty tissue engineering

Reconstructive surgery following breast cancer ablation is a surgical gold standard, but current options comprising autologous fatty tissue transfer and artificial soft tissue implants are inferior. With the advent of powerful biofabrication technologies, researchers for the first time have the tools to engineer life-like tissues with the ultimate goal of clinical application. Here, we apply multi-material stereolithographic bioprinting together with a novel sacrificial biomaterial system to engineer complex fatty tissue constructs. Biomaterials, cellular composition and cultivation conditions of these constructs were designed to enablein vitrocreation of vascularised fatty tissue. Cells within the constructs showed an overall good survival (>93%), indicated by live-dead cell staining, over the entire cultivation period of 27 d. Adipose-derived stem cells were successfully differentiatedin situ, forming fat vesicles and expressing adipocyte markers PPARγ, FAPB4 and S100B. Additionally, secretion of adipokines leptin and adiponectin into culture supernatants increased significantly. Endothelial cells vascularised the constructs, creating macro- and microvascular structures within the printed channels and extending beyond with culture time. Moreover, cells invaded into the surrounding hydrogel. The engineered fatty tissue constructs could serve as a base to develop patient-specific tissue building blocks with the final goal to achieve an all-natural reconstruction of the breast.

Intranasal delivery of engineered extracellular vesicles promotes neurofunctional recovery in traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of disability in adults, significantly affecting patients' quality of life. Extracellular vesicles (EVs) derived from human adipose-derived mesenchymal stem cells (hADSCs) have demonstrated therapeutic potential in TBI treatment. However, their limited targeting ability, short half-life, and low bioavailability present significant challenges for clinical application. In this study, we engineered extracellular vesicles (EEVs) by transfecting hADSCs with lentivirus and incorporating ultra-small paramagnetic nanoparticles (USPNs), resulting in EVs with enhanced miRNA expression and targeted delivery capabilities. These EEVs were administered intranasally to specifically target injury sites, effectively modulating the NF-κB signaling pathway to suppress neuroinflammation. In both in vitro and in vivo assessments, EEVs exhibited superior efficacy in promoting neurofunctional recovery and neurogenesis after brain injury compared to unmodified EVs. Furthermore, validation using human brain organoid models confirmed EEVs' remarkable ability to suppress neuroinflammation, offering a promising strategy for TBI treatment.

Application and Mechanism of Adipose Tissue-Derived Microvascular Fragments in Tissue Repair and Regeneration

One of the long-standing challenges in the field of tissue repair and regeneration is the rapid establishment of local microvascular circulation and restoration of perfusion at the site of defects or injuries. Recently, adipose tissue-derived microvascular fragments (ad-MVFs) have attracted increasing attention from researchers. Adipose tissue is rich in blood vessels, and significant progress has been made in the extraction and preservation techniques for microvascular fragments within it. Ad-MVFs promote tissue and organ repair and regeneration through three main mechanisms. First, they accelerate rapid and efficient vascularization at the injury site, enabling early vessel perfusion. Second, the stem cell components within ad-MVFs provide a rich source of cells for tissue and organ regeneration. Third, they play a role in immune regulation, facilitating integration with host tissues after implantation. The application methods of ad-MVFs are diverse. They can be directly implanted or pre-cultivated, facilitating their combination with various scaffolds and broadening their application scope. These properties have led to the wide use of ad-MVFs in tissue engineering, with promising prospects. This review demonstrates that ad-MVFs can serve as a reliable and highly feasible unit for tissue regeneration.

Adipose-Derived Stem Cell Specific Affinity Peptide-Modified Adipose Decellularized Scaffolds for Promoting Adipogenesis

Adipose-derived stem cells (ADSCs) are known to promote angiogenesis and adipogenesis. However, their limited ability to efficiently target and integrate into specific tissues poses a major challenge for ADSC-based therapies. In this study, we identified a seven-amino acid peptide sequence (P7) with high specificity for ADSCs using phage display technology. P7 was then covalently conjugated to decellularized adipose-derived matrix (DAM), creating an "ADSC homing device" designed to recruit ADSCs both in vitro and in vivo. The P7-conjugated DAM significantly enhanced ADSC adhesion and proliferation in vitro. After being implanted into rat subcutaneous tissue, immunofluorescence staining after 14 days revealed that P7-conjugated DAM recruited a greater number of ADSCs, promoting angiogenesis and adipogenesis in the surrounding tissue. Moreover, CD206 immunostaining at 14 days indicated that P7-conjugated DAM facilitated the polarization of macrophages to the M2 phenotype at the implantation site. These findings demonstrate that the P7 peptide has a high affinity for ADSCs, and its conjugation with DAM significantly improves ADSC recruitment in vivo. This approach holds great potential for a wide range of applications in material surface modification.

KLF5 enhances CXCL12 transcription in adipose-derived stem cells to promote endothelial progenitor cells neovascularization and accelerate diabetic wound healing

BACKGROUND

Adipose-derived stem cells (ADSCs) have been shown to accelerate diabetic wound healing by promoting neovascularization, though the underlying mechanisms are not fully understood. This study aims to explore whether ADSCs influence endothelial progenitor cells (EPCs) function to enhance diabetic wound healing.

METHODS

Human adipose-derived stem cells (hADSCs) were isolated from patient adipose tissue and cultured under normal and high glucose (HG) conditions. RNA sequencing analyzed gene expression, while immunofluorescence validated findings in patient wound tissues. Mouse adipose-derived stem cells (ADSCs) from C57BL/6 mice were evaluated in vitro for their effects on EPCs under HG using EdU, Transwell, and tube formation assays. A diabetic mouse wound model was used to assess ADSCs therapeutic effects via digital imaging, histology, and immunofluorescence. Kruppel-like factor 5 (KLF5), identified via the JASPAR database, was confirmed by immunohistochemistry and immunofluorescence. KLF5 and C-X-C motif chemokine 12 (CXCL12) expression levels were measured by enzyme-linked immunosorbent assay (ELISA), western blot, and quantitative reverse transcription polymerase chain reaction (RT-qPCR), and their relationship was validated through dual-luciferase assays.

RESULTS

We constructed a neovascularization-related signature (NRS) comprising 75 genes on the basis of differentially expressed genes (DEGs) linked to neovascularization. GO and KEGG analyses revealed that the NRS is primarily involved in vasculature development and receptor-ligand activity. Seven hub genes (CD34, CXCL12, FGF7, FGF18, FGF1, TEK, KIT) were identified and validated. In a diabetic mouse model, CXCL12 knockdown in ADSCs reduced their ability of promoting wound healing and neovascularization. KLF5 expression was lower in patients with diabetic ulcers and diabetic mice wound tissues compared with normal tissues, while ADSCs treatment significantly increased KLF5 expression in diabetic mice wounds. Dual-luciferase reporter assays confirmed KLF5 as an upstream transcription factor of CXCL12. Additionally, knocking down KLF5 in ADSCs impaired their therapeutic effects on diabetic wound healing. In vitro, the addition of exogenous CXCL12 recombinant protein restored EPCs proliferation, migration, and vasculogenic capacity in a high glucose environment after KLF5 silencing in ADSCs.

CONCLUSIONS

Our findings underscore the pivotal role of KLF5 in enhancing CXCL12 transcription within ADSCs, thereby facilitating EPC-mediated neovascularization and improving diabetic wound healing. Additionally, KLF5 emerges as a promising therapeutic target for accelerating tissue repair in diabetic wounds.

Efficient spheroid morphology assessment with a ChatGPT data analyst: implications for cell therapy

BACKGROUND

Adipose-derived stem cells (ADSCs) exhibit promising potential for the treatment of various diseases, including osteoarthritis. Spheroids derived from ADSCs are a viable treatment option with enhanced anti-inflammatory effects and tissue repair capabilities.

OBJECTIVE

SphereRing® is a rotating donut-shaped tube that efficiently produces large quantities of spheroids. However, accurately measuring spheroid size for spheroid quality assessment is challenging. This study aimed to develop an automated method for measuring spheroid size using deep learning through the ChatGPT Data Analyst for image recognition and processing.

METHOD

The area, perimeter, and circularity of spheroids generated with the SphereRing system were analyzed using ChatGPT Data Analyst and ImageJ. Measurement accuracy was validated using Bland-Altman analysis and scatter plot correlation coefficients.

RESULTS

ChatGPT Data Analyst was consistent with ImageJ for all parameters. Bland-Altman plots demonstrated strong agreement; most data points were within the 95% limits.

CONCLUSION

The ChatGPT Data Analyst provides a reliable and efficient alternative for assessing spheroid quality. This method reduces human error and improves reproducibility to enhance spheroid quality control. Thus, this method has potential applications in regenerative medicine.

The promise of mesenchymal stromal/stem cells in erectile dysfunction treatment: a review of current insights and future directions

Erectile dysfunction is a common and multifactorial condition that significantly impacts men's quality of life. Traditional treatments, such as phosphodiesterase type 5 inhibitors (PDE5i), often fail to provide lasting benefits, particularly in patients with underlying health conditions. In recent years, regenerative medicine, particularly stem cell therapies, has emerged as a promising alternative for managing erectile dysfunction. This review explores the potential of mesenchymal stromal/stem cells (MSCs) and their paracrine effects, including extracellular vesicles (EVs), in the treatment of erectile dysfunction. MSCs have shown remarkable potential in promoting tissue repair, reducing inflammation, and regenerating smooth muscle cells, offering therapeutic benefits in models of erectile dysfunction. Clinical trials have demonstrated positive outcomes in improving erectile function and other clinical parameters. This review highlights the promise of MSC therapy for erectile dysfunction, discusses existing challenges, and emphasizes the need for continued research to refine these therapies and improve long-term patient outcomes.

Enhancing fat graft survival: thymosin beta-4 facilitates mitochondrial transfer from ADSCs via tunneling nanotubes by upregulating the Rac/F-actin pathway

Autologous fat grafting is a widely used technique in plastic and reconstructive surgery, but its efficacy is often limited by the poor survival rate of transplanted adipose tissue. This study aims to enhance the survival of fat grafts by investigating the role of thymosin beta-4 (Tβ4) in facilitating mitochondrial transfer from adipose-derived stem cells (ADSCs) to adipocytes and newly formed blood vessels within the grafts via tunneling nanotubes (TNTs). We demonstrate that Tβ4 upregulates the Rac/F-actin pathway, leading to an increased formation of TNTs and subsequent transfer of mitochondria from ADSCs. This process mitigates oxidative stress, reduces apoptosis, and promotes revascularization, thereby improving the quality and volume retention of fat grafts. Our findings provide a novel mechanistic insight into the enhancement of fat graft survival and suggest that mitochondrial transplantation and Tβ4 are potential therapeutic strategies to improve clinical outcomes in autologous fat transfer procedures.

METTL3-modified exosomes from adipose-derived stem cells enhance the proliferation and migration of dermal fibroblasts by mediating m6A modification of CCNB1 mRNA

Skin scalded injury is a devastating condition. Exosomes derived from adipose-derived mesenchymal stem cells (ASC-exos) have been shown encouraging therapeutic potential in wound healing. Here, we explored the activity and mechanism of methyltransferase-like 3 (METTL3)-modified ASC-exos in the migration and proliferation of dermal fibroblasts. ASC-exos were isolated from mouse ASCs, characterized, and used to incubate mouse dermal fibroblasts. Fluorescence microscopy was used to analyze the transfer of ASC-exos into fibroblasts. Cell migration, invasion, proliferation, and viability were assessed by wound healing, transwell, 5-Ethynyl-2'-deoxyuridine (EdU), and Cell Counting Kit-8 (CCK-8) assays, respectively. Protein expression was tested by western blotting. The influence of METTL3 in cyclin B1 (CCNB1) was evaluated by methylated RNA immunoprecipitation (MeRIP), actinomycin D treatment and quantitative PCR assays. ASC-exos significantly increased the proliferative, invasive, and migratory potentials of dermal fibroblasts. Overexpression of METTL3 resulted in elevated proliferation, invasiveness, and migratory capacity in dermal fibroblasts. Furthermore, METTL3-modified ASC-exos derived from METTL3-increased ASCs exerted more significantly promoting effects on fibroblast proliferation and migration than ASC-exos. Mechanistically, METTL3 upregulated CCNB1 by affecting its mRNA m6A modification. Additionally, reduction of CCNB1 had a counteracting impact on the effects of METTL3-modified ASC-exos in dermal fibroblasts. Our study shows that METTL3-modified ASC-exos enhance the migration and invasion of dermal fibroblasts by mediating CCNB1 mRNA m6A modification, raising hopes that these exosomes might serve as a therapeutic option for scalded skin wound repair.

Thermal-crosslinked acellular dermal matrix combined with adipose-derived stem cells to regenerate vascularized adipose tissue

The reconstruction of large-sized soft tissue defects remains a substantial clinical challenge, with adipose tissue engineering emerging as a promising solution. The acellular dermal matrix (ADM), known for its intricate spatial arrangement and active cytokine involvement, is widely employed as a scaffold in soft tissue engineering. Since ADM shares high similarity with decellularized adipose matrix, it holds potential as a substitute for adipose tissue. This study explores the adipogenic ability of a spongy material derived from ADM via vacuum-thermal crosslinking (T-ADM), characterized by high porosity, adjustable thickness, and suitable mechanical strength. Adipose-derived stem cells (ADSCs) are considered ideal seed cells in adipose tissue engineering. Nevertheless, whether pre-adipogenic induction is necessary before their incorporation remains debatable. In this context, ADSCs, both with and without pre-adipogenic induction, were seeded into T-ADM to regenerate vascularized adipose tissue. A comparative analysis of the two constructs was performed to evaluate angiogenesis and adipogenesisin vitro, and tissue regeneration efficacyin vivo. Additionally, RNA-seq analysis was utilized to investigate the potential mechanisms. The results showed that T-ADM exhibited good performance in terms of volume retention and maintenance of adipocyte phenotype, confirming its suitability as a scaffold for adipose tissue engineering.In-vitrooutcomes demonstrated that pre-adipogenic induction enhanced the adipogenic level of ADSCs, but reduced their ability to promote vascularization. Furthermore, constructs utilizing pre-induced ADSCs showed an insignificant superiority inin-vivofat formation, and neovascularization compared with those with non-induced ADSCs, which may be attributed to similar macrophage regulation, and balanced modulation of the proliferator-activated receptor-γand hypoxia-inducible factor 1αpathways. Consequently, the direct use of ADSCs is advocated to streamline the engineering process and reduce associated costs. The combined strategy of T-ADM with ADSCs proves to be feasible, convenient and effective, offering substantial potential for addressing large-sized tissue deficits and facilitating clinical applications.

Amine-Functionalized Gellan Gum-Based Hydrogel Loaded with Adipose Stem Cell-Derived Small Extracellular Vesicles: An In Vitro Proof of Concept for Enhancing Diabetic Foot Ulcer Healing

Diabetic foot ulcers (DFUs) are chronic wounds and a common complication of diabetes. A promising strategy in the treatment of DFUs involves the use of stem cell derivatives, such as small extracellular vesicles (sEVs), which can enhance cell proliferation and reduce inflammation while avoiding immunogenic responses. In this study, we evaluated the ability of adipose mesenchymal stem cell- (ASC)-derived sEVs to enhance the proliferation of human fibroblasts, which play a crucial role in wound regenerative processes. To mimic the inflammatory environment of DFUs, fibroblasts were cultured into the gellan gum (GG) modified with ethylenediamine (EDA) hydrogel scaffolds loaded with ASC-derived sEVs, under pro-inflammatory cytokines. Our comparative analysis demonstrated that sEVs loaded in GG-EDA hydrogel improved fibroblast viability in pro-inflamed conditions while retaining the anti-inflammatory and immunomodulatory properties of their cells of origin. By modulating the gene expression profile of fibroblasts to promote cell proliferation, wound healing and re-epithelialization, our system presents a promising therapeutic strategy for DFU healing.

The role of lncRNA in the differentiation of adipose-derived stem cells: from functions to mechanism

Adipose-derived stem cells (ADSCs) have become one of the best seed cells widely studied and concerned in tissue engineering because of their rich sources and excellent multi-directional differentiation ability, which are expected to play a practical application role in tissue defect, osteoporosis, plastic surgery, and other fields. However, the differentiation direction of ADSCs is regulated by complex factors. Long non-coding RNAs (lncRNAs) are RNA molecules longer than 500 nucleotides that do not encode proteins and can act as signaling RNAs in response to intracellular and extracellular stimuli. Recently, accumulating evidence has revealed that lncRNAs could regulate the cell cycle and differentiation direction of ADSCs through various mechanisms, including histone modification, binding to RNA-binding proteins, and regulating the expression of miRNAs. Therefore, enriching and elucidating its mechanism of action as well as targeting lncRNAs to regulate ADSCs differentiation have potential prospects in tissue regeneration applications such as bone, blood vessels, and adipose. In this review, we summarize the role and mechanism of lncRNAs and its complexes in the multi-directional differentiation of ADSCs and discuss some potential approaches that can exert therapeutic effects on tissue defects by modulating the expression level of lncRNAs in ADSCs. Our work might provide some new research directions for the clinical applications of tissue engineering.

Model Organoids: Integrated Frameworks for the Next Frontier of Healthcare Advancements

The morphogenetic events leading to tissue formation can be recapitulated using organoids, which allows studying new diseases and modelling personalized medicines. In this review, culture systems comparable to human organs are presented, these organoids are created from pluripotent stem cells or adult stem cells. The efficient and reproducible models of human tissues are discussed for biobanking, precision medicine and basic research. Mechanisms used by these model systems with an overview of models from human cells are also covered. As human physiology is different from animals, culture conditions and tissue limits often become challenging. Organoids offer novel approaches for such cases with rapid screening, transplantation studies and in immunotherapy. Discrepancies with large datasets can be handled with an integrated framework of artificial intelligence or AI and machine learning. An attempt has been made to show the improved effectiveness, simplified iterations, along with image analysis that are possible from this synergy. AI-assisted organoids have the potential to transform healthcare by improving disease understanding and accelerating clinical decision-making through personalized and precision medicine.

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.

3D bioprinted multi-layered cell constructs with gradient core-shell interface for tendon-to-bone tissue regeneration

Rotator cuff tears are common among physically active individuals and often require surgical intervention owing to their limited self-healing capacity. This study proposes a new bioprinting approach using bone- and tendon tissue-specific bioinks derived from decellularized extracellular matrix, supplemented with hydroxyapatite and TGF-β/poly(vinyl alcohol) to fabricate engineered tendon-to-bone complex tissue. To achieve this goal, a core-shell nozzle system attached to a bioprinter enables the effective and simultaneous fabrication of aligned tendon tissue, a gradient tendon-bone interface (TBI), and a mechanically improved bone region, mimicking the native tendon-to-bone structure. In vitro evaluation demonstrated the well-directed differentiation of human adipose stem cells towards osteogenic and tenogenic lineages in the bone and tendon constructs. In the graded TBI structure, further facilitated fibrocartilage formation and enhanced the integration of tendon-to-bone tissues compared to non-graded structures in vitro. Furthermore, using a rabbit rotator cuff tear model, implantation of the biologically graded constructs significantly promoted the rapid regeneration of full-thickness tendon-to-bone tissue, including the formation of a high-quality TBI in vivo. This bioprinting approach not only improved mechanical properties and tissue integration but also enhanced angiogenesis and extracellular matrix (ECM) formation, demonstrating its potential as a promising platform for the regeneration of tendon-to-bone complex tissues.

Standardization and consensus in the development and application of bone organoids

Organoids, self-organized structures derived from stem cells cultured in a specific three-dimensional (3D) in vitro microenvironment, have emerged as innovative platforms that closely mimic in vivo cellular behavior, tissue architecture, and organ function. Bone organoids, a frontier in organoid research, can replicate the complex structures and functional characteristics of bone tissue. Recent advancements have led to the successful development of bone organoids, including models of callus, woven bone, cartilage, trabecular bone, and bone marrow. These organoids are widely utilized in establishing bone-related disease models, bone injury repair, and drug screening. However, significant discrepancies remain between current bone organoids and human skeletal tissues in terms of morphology and functionality, limiting their ability to accurately model human bone physiology and pathology. To address these challenges and promote standardization in the construction, evaluation, and application of bone organoids, we have convened experts and research teams with substantial expertise in the field. By integrating existing research findings, this consortium aims to establish a consensus to guide future research and application of bone organoids.

A temperature responsive hydrogel encapsulated with adipose-derived stem cells and melanin promotes repair and regeneration of endometrial injury

The endometrium, the inner lining of the uterus, assumes a crucial role in the female reproductive system. Disorders and injuries impacting the endometrium can lead to profound consequences, including infertility and compromised women's overall health. Recent advancements in stem cell research have opened new possibilities for the treatment and repair of endometrial issues. In the present study, we constructed a degradable hydrogel by loading adipose-derived stem cells (ADSCs) and melanin nanoparticles (MNP). In vitro cell experiments validated the biocompatibility of the prepared hydrogels and their adeptness in encapsulating ADSCs. Subsequently, we explored the impact of hydrogel@ADSC@MNP constructs in the healing process of uterine injury in mice. The results indicated that hydrogel@ADSC@MNP could augment endometrial thickness and ameliorate endometrial interstitial fibrosis. The injured tissue adjacent to hydrogel@ADSC@MNP constructs exhibited higher levels of bFGF, IGF-1, and VEGFA compared with the corresponding tissue in mice receiving hydrogel constructs alone or in the model group. Furthermore, the hydrogel@ADSC@MNP system enhanced the proliferative capabilities of uterine endometrial cells, facilitated microvasculature regeneration, and reinstated the endometrium's capacity to receive the embryos. Our findings strongly suggest that the hydrogel@ADSC@MNP system holds significant promise for repairing and regenerating damaged endometrium.

A novel cytoprotective organ perfusion platform for reconstructing homeostasis of DCD liver while alleviating IRI injury

Pump is a vital component for expelling the perfusate in small animal isolated organ normothermic machine perfusion (NMP) systems whose flexible structure and rhythmic contraction play a crucial role in maintaining perfusion system homeostasis. However, the continuous extrusion forming with the rigid stationary shaft of the peristaltic pumps can damage cells, leading to metabolic disorders and eventual dysfunction of transplanted organs. Here, we developed a novel biomimetic blood-gas system (BBGs) for preventing cell damage. This system mimics the cardiac cycle and features an adjustable inspiratory-to-expiratory (IE) ratio to mitigate acidosis caused by continuous oxygen inhalation. In our study, adipose stem cells (ADSCs) were cultured within the circulatory system for 10 min, 2, and 4 h. Compared to the peristaltic pump, the BBGs significantly reduced cell apoptosis and morphological injury while enhancing cell proliferation and adhesion. Additionally, when the supernatant from ADSCs was introduced to LPS-induced macrophages for 24 h, the BBGs group demonstrated a more pronounced anti-inflammatory effect, characterized by reduced M1 macrophage expression. Besides, with isolated rat livers from donation after circulatory death (DCD) perfusion with ADSCs for 6 h by the BBGs, we detected fewer apoptotic cells and a reduced inflammatory response, evidenced by down-regulated TNF-α expression. The development of BBGs demonstrates the feasibility of recreating physiological liquid-gas circulation in vitro, offering an alternative platform for isolated organ perfusion, especially for applications involving cell therapy.

Advances in meniscus tissue engineering: Towards bridging the gaps from bench to bedside

Meniscus is vital for maintaining the anatomical and functional integrity of knee. Injuries to meniscus, commonly caused by trauma or degenerative processes, can result in knee joint dysfunction and secondary osteoarthritis, while current conservative and surgical interventions for meniscus injuries bear suboptimal outcomes. In the past decade, there has been a significant focus on advancing meniscus tissue engineering, encompassing isolated scaffold strategies, biological augmentation, physical stimulus, and meniscus organoids, to improve the prognosis of meniscus injuries. Despite noteworthy promising preclinical results, translational gaps and inconsistencies in the therapeutic efficiency between preclinical and clinical studies exist. This review comprehensively outlines the developments in meniscus tissue engineering over the past decade (Scheme 1). Reasons for the discordant results between preclinical and clinical trials, as well as potential strategies to expedite the translation of bench-to-bedside approaches are analyzed and discussed.

Impact of photobiomodulation on neural embryoid body formation from immortalized adipose-derived stem cells

BACKGROUND

Embryoid bodies (EBs) are three-dimensional (3D) multicellular cell aggregates that are derived from stem cell and play a pivotal role in regenerative medicine. They recapitulate many crucial aspects of the early stages of embryonic development and is the first step in the generation of various types of stem cells, including neuronal stem cells. Current methodologies for differentiating stem cells into neural embryoid bodies (NEBs) in vitro have advanced significantly, but they still have limitations which necessitate improvement. Photobiomodulation (PBM) a low powered light therapy is a non-invasive technique shown to promote stem cell proliferation and differentiation.

METHODS

This in vitro study elucidated the effects of photobiomodulation (PBM) on the differentiation of immortalized adipose-derived stem cells (iADSCs) into NEBs within a 3D cell culture environment. The study utilized PBM at wavelengths of 825 nm, 525 nm, and a combination of both, with fluences of 5 and 10 J/cm2. Morphology, viability, metabolic activity, and differentiation following PBM treatment was analysed.

RESULTS

The results revealed that the effects of photobiomodulation (PBM) are dose dependent. PBM, at 825 nm with a fluence of 10 J/cm2, significantly enhanced the size of neural embryoid bodies (NEBs), improved cell viability and proliferation, and reduced lactate dehydrogenase (LDH) levels, indicating minimal cell damage. Interestingly, the stem cell marker CD 44 was upregulated at 5 J/cm2 in all treatment groups at 24 and 96 hpi, CD105 increased with 825 nm at 10 J/cm2 at 24 hpi, which may be attributed to a heterogeneous cell population within the NEBs. Pax6 expression showed transient activation. Nestin was upregulated at 825 nm with 10 J/cm2 at 96 hpi, suggesting a promotion of neural precursor populations. GFAP an intermediate filament protein was upregulated at 825 nm at 10 J/cm2 at both 24 and 96 hpi. SOX2, a pluripotency marker, was expressed at 5 J/cm2 across all wavelengths. Neu N a neuronal nuclei marker was expressed at 5 J/cm2 in all treatments at 24 hpi and over time the expression was observed in all treatment groups at 10 J/cm2.

CONCLUSION

In conclusion, the application of PBM at 825 nm with a fluence of 10 J/cm2 during the differentiation of iADSCs into NEBs resulted in optimal differentiation. Notably, the neuronal marker Nestin was significantly upregulated, highlighting the potential of the PBM approach for enhancing neuronal differentiation its promising applications in regenerative medicine.

Enhanced Wound Healing and Autogenesis Through Lentiviral Transfection of Adipose-Derived Stem Cells Combined with Dermal Substitute

BACKGROUND

Burns and chronic ulcers may cause severe skin loss, leading to critical health issues like shock, infection, sepsis, and multiple organ failure. Effective healing of full-thickness wounds may be challenging, with traditional methods facing limitations due to tissue shortage, infection, and lack of structural support.

METHODS

This study explored the combined use of gene transfection and dermal substitutes to improve wound healing. We used the DGTM (genes: DNP63A, GRHL2, TFAP2A, and MYC) factors to transfect adipose-derived stem cells (ADSCs), inducing their differentiation into keratinocytes. These transfected ADSCs were then incorporated into Pelnac® dermal substitutes to enhance vascularization and cellular proliferation for better healing outcomes.

RESULTS

Gene transfer using DGTM factors successfully induced keratinocyte differentiation in ADSCs. The application of these differentiated cells with Pelnac® dermal substitute to dermal wounds in mice resulted in the formation of skin tissue with a normal epidermal layer and proper collagen organization. This method alleviates the tediousness of the multiple transfection steps in previous protocols and the safety issues caused by using viral transfection reagents directly on the wound. Additionally, the inclusion of dermal substitutes addressed the lack of collagen and elastic fibers, promoting the formation of tissue resembling healthy skin rather than scar tissue.

CONCLUSION

Integrating DGTM factor-transfected ADSCs with dermal substitutes represents a novel strategy for enhancing the healing of full-thickness wounds. Further research and clinical trials are warranted to optimize and validate this innovative approach for broader clinical applications.

Novel cocktail therapy based on multifunctional supramolecular hydrogel targeting immune-angiogenesis-nerve network for enhanced diabetic wound healing

Diabetes-associated chronic skin wounds present a formidable challenge due to inadequate angiogenesis and nerve regeneration during the healing process. In the present study, we introduce a groundbreaking approach in the form of a novel cocktail therapy utilizing a multifunctional supramolecular hydrogel. Formulated through the photo-crosslinking of gelatinized aromatic residues and β-cyclodextrin (β-CD), this injectable hydrogel fosters weak host-guest interactions, offering a promising solution. The therapeutic efficacy of the hydrogel is realized through its integration with adipose-derived stem cells (ADSCs) and lipid nanoparticles encapsulating ginsenoside RG1 and Stromal cell-derived factor-1 (SDF-1). This strategic combination directs ADSCs to the injury site, guiding them toward neurogenic specialization while establishing an advantageous immunomodulatory environment through macrophage reprogramming. The synergistic effects of the newly differentiated nerve cells and the regenerative cytokines secreted by ADSCs contribute significantly to enhanced angiogenesis, ultimately expediting the diabetic wound healing process. To summarize, this innovative hydrogel-based therapeutic system represents a novel perspective for the management of diabetic wounds by concurrently targeting immune response, angiogenesis, and nerve regeneration-a pivotal advancement in the quest for effective solutions in diabetic wound care.

Gelatin microcarriers as an effective adipose-derived stem cells delivery strategy in osteoarthritis treatment

Despite their clinical success, stem cells (SCs) in the treatment of osteoarthritis (OA) are limited by lower retention efficiency and restricted paracrine function. The development of effective SCs culture and delivery systems to maintain or promote SCs paracrine function is urgently needed. In this study, we focused on gelatin microcarriers with different sizes as SCs culture scaffold for OA therapy. The effect of culturing adipose-derived stem cells (ADSCs) on different size microcarriers (180 μm and 320 μm) to promote paracrine function was evaluated. The secretome of ADSCs cultured on microcarriers more effectively regulated macrophages and chondrocytes in a direction favorable to OA healing compared to culture plates. In particular, microcarriers with ADSCs effectively reduced the coefficient of friction at the cartilage interface. Injection low-dose ADSCs without and with different size microcarriers into the knee joints in rats' OA model was achieved. Even better OA therapeutic effects were achieved by using smaller size (higher curvature) microcarriers to deliver ADSCs at low doses. Microcarrier-based cell delivery strategies offer potential solution method for OA therapy.

Curcumin Inhibits Oxidative Stress and Apoptosis Induced by H2O2 in Bovine Adipose-Derived Stem Cells (bADSCs)

In livestock production, oxidative stress (OS) is ubiquitous, reducing animal productivity and product quality. Hence, investigating the mechanisms of oxidative stress in livestock and inhibiting oxidative stress-induced damage is crucial. Curcumin, a plant-derived bioactive compound, exhibits antioxidant and anti-apoptotic properties. Adipose-derived stem cells (ADSCs) from animal adipose tissue are easily accessible and possess multilineage differentiation potential. Therefore, this work utilized bovine ADSCs to establish an oxidative stress model and investigated the effects of curcumin on oxidative stress and apoptosis. Firstly, bovine ADSCs were isolated and cultured from fetal calf subcutaneous adipose tissue. Their surface markers were identified by immunofluorescence, confirming the expression of CD29, CD44, CD73, CD90, CD105 and Vimentin, but not CD34, indicative of mesenchymal stem/progenitor cell characteristics. Secondly, to explore the effects of curcumin on oxidative damage and apoptosis in bovine ADSCs, an oxidative stress model was induced using H2O2. CCK-8 assays showed significantly reduced cell viability and SOD activity, along with increased malondialdehyde (MDA) and reactive oxygen species (ROS) levels, indicating successful modeling. RT-qPCR further confirmed that 500 μM of H2O2 treatment for 24 h promoted apoptosis. Herein, CCK-8 assays indicated a significant reduction in cell viability at >8 μM of curcumin. Thirdly, using 4 μM and 8 μM of curcumin for pre-protection, 8 μM maintained SOD activity, reduced MDA and ROS, inhibited apoptosis-related gene changes (Bcl-2, Bax, Caspase-3), and suppressed apoptosis according to a TUNEL assay. Fourthly, curcumin's autophagy-inducing potential was hypothesized, which was confirmed by increased LC3-II and decreased P62 expression upon co-treatment with 3-MA. 3-MA inhibited curcumin's antioxidant and anti-apoptotic effects, suggesting that curcumin's antioxidant and anti-apoptotic roles may involve autophagy induction. In conclusion, bovine ADSCs are abundant, easily accessible, and multipotent, making them suitable for in vitro expansion. Curcumin alleviated H2O2-induced oxidative stress in bovine ADSCs, with curcumin also inhibiting apoptosis, likely through autophagy induction. This study validates the protective role of curcumin in bovine ADSCs, with potential applications in livestock production.

ACL injury management: a comprehensive review of novel biotherapeutics

The anterior cruciate ligament (ACL) is integral to the stability of the knee joint, serving to limit anterior tibial translation and regulate rotational movements. ACL injuries are among the most common and debilitating forms of knee trauma, often resulting in joint effusion, muscular atrophy, and diminished athletic capabilities. Despite the established efficacy of ACL reconstruction as the standard treatment, it is not uniformly successful. Consequently, there is a growing interest in novel biotherapeutic interventions as potential alternatives. This comprehensive review examines the latest advancements in ACL biotherapy, encompassing the application of hyaluronic acid, self-assembled short peptides, growth factors, stem cell therapy, gene therapy, platelet-rich plasma therapy, bone marrow aspirate concentrate cells, extracorporeal shock wave, electrical stimulation and cross bracing protocol. The collective aim of these innovative treatments is to facilitate the restoration of the ACL's native biological and biomechanical integrity, with the ultimate goal of enhancing clinical outcomes and the functional recovery of affected individuals.

Research on the TSPAN6 regulating the secretion of ADSCs-Exos through syntenin-1 and promoting wound healing

BACKGROUND

Exosomes (Exos) from adipose-derived stem cells (ADSCs) have a high inclusion content and low immunogenicity, which helps to control inflammation and accelerate the healing of wounds. Unfortunately, the yield of exosomes is poor, which raises the expense and lengthens the treatment period in addition to impairing exosomes' therapeutic impact. Thus, one of the key problems that needs to be resolved in the current exosome study is increasing the exosome yield.

METHODS

Tetraspanin-6 (TSPAN6) overexpression and knockdown models of ADSCs were constructed to determine the number of exosomes secreted by each group of cells as well as the number of multivesicular bodies (MVBs) and intraluminal vesicles (ILVs) within the cells. Subsequently, the binding region of the interaction between TSPAN6 and syntenin-1 was identified using the yeast two-hybrid assay, and the interaction itself was identified by immunoprecipitation. Finally, cellular and animal studies were conducted to investigate the role of each class of exosomes.

RESULTS

When compared to the control group, the number of intracellular MVBs and ILVs was significantly larger, and the number of ADSCsTSPAN6+-Exos was more than three times higher. However, TSPAN6's ability to stimulate exosome secretion was reduced as a result of syntenin-1 knockdown. Additional yeast two-hybrid assay demonstrated that the critical structures for their interaction were the N-terminal, Postsynaptic density protein 95/Discs large protein/Zonula occludens 1 (PDZ1), and PDZ2 domains of syntenin-1, and the C-terminal of TSPAN6. In animal trials, the wound healing rate was best in the ADSCsTSPAN6+-Exos group, while cellular experiments demonstrated that ADSCsTSPAN6+-Exos better enhanced the proliferation and migration of human skin fibroblasts (HSFs) and human umbilical vein endothelial cells (HUVECs).

CONCLUSION

TSPAN6 stimulates exosome secretion and formation, as well as the creation of MVBs and ILVs in ADSCs. Syntenin-1 is essential for TSPAN6's stimulation of ADSCs-Exos secretion. Furthermore, ADSCsTSPAN6+-Exos has a greater ability to support wound healing, angiogenesis, and the proliferation and migration of a variety of cells.

Role of mesenchymal cells in enhancing cosmetic outcomes for autologous augmented fat transfers for facial rejuvenation and reconstructive surgery

In recent years, autologous fat transfer (AFT) has gained popularity for reconstructive and cosmetic procedures due to its minimally invasive nature and natural-looking results. However, limitations such as unpredictable fat resorption and safety concerns persist. To address these issues, researchers have explored incorporating adipose-derived stromal cells (ADSCs) into fat grafts. Enriching fat grafts with ADSCs, often through stromal vascular fraction (SVF), shows promise in regenerative medicine, though their effectiveness remains debated. Some studies suggest no significant difference in outcomes, while others indicate that ADSCs are more effective in larger-volume grafts. This implies that ADSC-enriched grafts might achieve similar results to traditional methods, with volume retention being a crucial success indicator. Given that these cosmetic procedures impact body image and self-confidence, innovative techniques like ADSC-enriched grafts are crucial for improving clinical outcomes. ADSCs are favoured for their abundance in adipose tissue and wound healing properties, which enhance cosmetic results. Patients receiving ADSC-enriched grafts show increased collagen, elastin, and CD31 levels, and better graft survival compared to those with traditional fat grafting, reducing the need for repeat procedures. Recent applications in patients with fibrotic facial deformities have demonstrated positive outcomes both cosmetically and psychologically. This mini-review evaluates the efficacy and benefits of ADSC-enriched AFT for facial rejuvenation and reconstruction, focusing on graft retention and overall procedural outcomes.

3D-printed biomimetic scaffolds loaded with ADSCs and BMP-2 for enhanced rotator cuff repair

Rotator cuff tear repair poses significant challenges due to the complex gradient interface structure. In the face of disease-related disruptions in the tendon-bone interface (TBI), the strategy of constructing a biomimetic scaffold is a promising avenue. A novel 3D-printed rotator cuff scaffold loaded adipose stem cells (ADSCs), bone morphogenetic protein-2 (BMP-2), and collagen type I (COL I). The efficiency of the slow-release BMP-2 design depended on the dopamine-hyaluronic acid (HAD) and BMP-2 reaction. The cumulative release of BMP-2 was 44.97 ± 5.45% at 4 weeks. The 3D-printed bilayer scaffold, incorporating COL I and BMP-2, effectively promoted the differentiation of ADSCs into osteogenic, tenogenic, and chondrogenic lineages in vitro. The combination of 3D-printed bioactive scaffolds and ADSCs demonstrated a superior repair effect on rotator cuff injuries in vivo. Therefore, these findings indicates that the 3D-printed biomimetic scaffold loaded with ADSCs and BMP-2 holds potential as a promising graft for TBI healing.

Comparison of adipose derived stromal cells cultured on fibroin scaffolds fabricated by salt-leaching and by freeze-thawing

Fibroin, the main structural protein of Bombyx mori silk, is known for its mechanical properties, its biocompatibility and degradation characteristics in vivo. Various studies investigate its uses as cell carrier and/or material for surgical implants. Multiple protocols have been established to isolate fibroin from silk fibers and to produce scaffolds and films from fibroin solution. There is only limited literature available on how fibroin scaffolds manufactured by different methods compare to each other in terms of performance as cell carriers. This study compares the behaviour of human adipose derived stromal cells (ADSC) seeded on fibroin scaffolds produced by (i) salt-leaching and (ii) freeze-thawing. One type of freeze-thawing scaffold (poresize ≪ 315 μm) and three types of salt-leaching scaffolds (poresize ranging from 315 μm to 1000 μm) were used for this comparison. Measuring the DNA concentration on the seeded scaffolds as well as the seeded cells metabolic activity, we were able to determine freeze-thawed scaffolds to be superior for cell-seeding. ADSC seeded on salt-leaching scaffolds displayed a stronger downregulation of serum deprivation response gene than cells seeded on freeze-thaw scaffolds. In sum, our findings show that salt-leaching scaffolds offering different pore sizes differed much less among each other than salt-leaching from freeze-thawing scaffolds in terms of cell accommodation. Our work underlines the importance of physicochemical scaffold properties directly linked to different manufacturing methods and their influence on the cell seeding capacity of silk fibroin based carriers.

Optimization and Implication of Adipose-Derived Stem Cells in Craniofacial Bone Regeneration and Repair

Adipose-derived stem cells (ADSCs) have emerged as a promising resource for craniofacial bone regeneration due to their high abundance and easy accessibility, significant osteogenic potential, versatile applications, and potential for personalized medicine, which underscore their importance in this field. This article reviews the current progress of preclinical studies that describe the careful selection of specific ADSC subpopulations, key signaling pathways involved, and usage of various strategies to enhance the osteogenic potential of ADSCs. Additionally, clinical case reports regarding the application of ADSCs in the repair of calvarial defects, cranio-maxillofacial defects, and alveolar bone defects are also discussed.

Exosome-based cell therapy for diabetic foot ulcers: Present and prospect

Diabetic foot ulcers (DFUs) represent a serious complication of diabetes with high incidence, requiring intensive treatment, prolonged hospitalization, and high costs. It poses a severe threat to the patient's life, resulting in substantial burdens on patient and healthcare system. However, the therapy of DFUs remains challenging. Therefore, exploring cell-free therapies for DFUs is both critical and urgent. Exosomes, as crucial mediators of intercellular communication, have been demonstrated potentially effective in anti-inflammation, angiogenesis, cell proliferation and migration, and collagen deposition. These functions have been proven beneficial in all stages of diabetic wound healing. This review aims to summarize the role and mechanisms of exosomes from diverse cellular sources in diabetic wound healing research. In addition, we elaborate on the challenges for clinical application, discuss the advantages of membrane vesicles as exosome mimics in wound healing, and present the therapeutic potential of exosomes and their mimetic vesicles for future clinical applications.