Umbilical cord-derived Wharton's jelly for treatment of knee osteoarthritis: study protocol for a non-randomized, open-label, multi-center trial

TNFRSF11B-modified umbilical cord mesenchymal stem cells as a novel strategy for bone-related diseases by suppressing osteoclast activity

BACKGROUND AND OBJECTIVE

Mesenchymal stem cells (MSCs), possessing multilineage potential, are capable of differentiating into osteoblasts and thus serve as suitable seed cells for bone regeneration. Tumor necrosis factor receptor superfamily member 11B (TNFRSF11B) gene encodes osteoprotegerin (OPG), which has a critical role in repressing osteoclast differentiation and has been reported to influence the adipogenic differentiation of bone marrow mesenchymal stem cells (BMMSCs). Nevertheless, the impact of TNFRSF11B on the osteogenic differentiation of umbilical cord mesenchymal stem cells (UCMSCs) remains unclear. This study aimed to investigate the role of TNFRSF11B in the osteogenesis of UCMSCs and bone remodeling.

METHODS

Differentially expressed genes (DEGs) were identified from the GEO database using R software. TNFRSF11B was transduced into UCMSCs by a lentiviral vector. Cell differentiation capacity was assessed by ALP staining, TRAP staining, and qRT-PCR assay. Proteomic analysis was performed to investigate the key proteins in TNFRSF11B-OE-UCMSCs that inhibit osteoclast differentiation.

RESULTS

We found that the TNFRSF11B gene was upregulated during osteogenic differentiation and downregulated during adipogenic differentiation of UCMSCs. UCMSCs overexpressing the TNFRSF11B gene were successfully generated via lentivirus transfection. However, neither the overexpression of TNFRSF11B nor treatment with exogenous OPG protein was sufficient to enhance the osteogenic potential of UCMSCs in vitro. Conditioned medium from TNFRSF11B-overexpressing UCMSCs significantly suppressed RANKL-induced osteoclast differentiation, while no significant effect was observed on osteoblast differentiation compared to the control group. Proteome analysis revealed that in the TNFRSF11B-OE-CM group, the expression of C1R, MDH1, and ACLY was significantly downregulated, while the expression of FETUB and METRNL was upregulated in the TNFRSF11B-OE-CM group, which was associated with the inhibition of osteoclast differentiation.

CONCLUSION

This study demonstrates that although TNFRSF11B overexpression does not promote osteogenesis in UCMSCs, it may participate in regulating bone remodeling by inhibiting osteoclast differentiation.

Therapeutic potential of stem cell-derived exosomes for bone tissue regeneration around prostheses

Artificial joint replacement is a widely recognized treatment for arthritis and other severe joint conditions. However, one of the primary causes of failure in joint replacements is the loosening of the prosthesis. After implantation, wear particles between the implant and the adjacent bone tissue are the principal contributors to this loosening. Recently, exosomes have garnered significant interest due to their low immunogenicity and effective membrane binding. They have shown potential in promoting bone regeneration via the paracrine pathway. This review examines the role and mechanisms of exosomes derived from mesenchymal stem cells (MSCs) in bone regeneration, their impact on the integration of various implants into surrounding bone tissue and current challenges and future directions for the clinical application of exosomes. The Translational Potential of this Article: Emerging evidence suggests that mesenchymal stem cell-derived exosomes may offer a promising therapeutic strategy for aseptic prosthesis loosening, potentially mediated through mechanisms such as modulation of inflammatory responses, suppression of osteoclastogenesis, enhancement of osteogenic differentiation and facilitation of bone regeneration. Preclinical studies further indicate that the therapeutic potential of these extracellular vesicles could be optimized through bioengineering strategies, including surface modification and cargo-loading techniques, warranting further investigation to advance their clinical translation.

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.

Potential and challenges of utilizing exosomes in osteoarthritis therapy (Review)

Exosomes are integral to the pathophysiology of osteoarthritis (OA) due to their roles in mediating intercellular communication and regulating inflammatory processes. Exosomes are integral to the transport of bioactive molecules, such as proteins, lipids and nucleic acids, which can influence chondrocyte behavior and joint homeostasis. Given their properties of regeneration and ability to target damaged tissues, exosomes represent a promising therapeutic avenue for OA treatment. Exosomes have potential in promoting cartilage repair, reducing inflammation and improving overall joint function. However, several challenges remain, including the need for standardized isolation and characterization methods, variability in exosomal content, and regulatory hurdles. The present review aims to provide a comprehensive overview of the current understanding of exosome mechanisms in OA and their therapeutic potential, while also addressing the ongoing challenges faced in translating these findings into clinical practice. By consolidating existing research, the present review aims to pave the way for future studies aimed at optimizing exosome‑based therapies for effective OA management.

Drug delivery for age-related bone diseases: From therapeutic targets to common and emerging therapeutic strategies

With the accumulation of knowledge on aging, people have gradually realized that among the many factors that cause individual aging, the accumulation of aging cells is an essential cause of organ degeneration and, ultimately, age-related diseases. Most cells present in the bone microenvironment gradually age over time, leading to an imbalance of osteogenesis, osteoclastogenesis, adipogenesis, and chondrogenesis. This imbalance contributes to age-related bone loss and the development of age-related bone diseases, such as osteoporosis. Bone aging can prolong the lifespan and delay the development of age-related diseases. Nanoparticles have controllable and stable physical and chemical properties and can precisely target different tissues and organs. By preparing multiple easily modified and biocompatible nanoparticles as different drug delivery carriers, specifically targeting various diseased tissues for controlled-release and sustained-release administration, the delivery efficiency of drugs can be significantly improved, and the toxicity and side effects of drugs can be substantially reduced, thereby improving the therapeutic effect of age-related bone diseases. In addition, other novel anti-aging strategies (such as stem cell exosomes) also have significant scientific and practical significance in anti-aging research on age-related bone diseases. This article reviews the research progress of various nano-drug-loaded particles and emerging anti-aging methods for treating age-related bone diseases, offering new insights and directions for precise targeted clinical therapies.

Evaluation of the impact of customized serum-free culture medium on the production of clinical-grade human umbilical cord mesenchymal stem cells: insights for future clinical applications

BACKGROUND

The selection of suitable culture medium is critical for achieving good clinical outcomes in cell therapy. To support the commercial application of stem cell therapy, customized culture media not only need to promote stem cell proliferation, but also need to save costs and meet industrial requirements for inter-batch consistency, efficacy, and biosafety. In this study, we developed a series of serum-free media (SFM) and elucidated the effects between different SFM, as well as between SFM and serum-containing meida (SCM), on human umbilical cord mesenchymal stem cells (hUC-MSCs) phenotype and function. We analyze and emphasize from the perspectives of clinical and commercial application why research on customized culture media is critical for the success of enterprises developing novel cellular therapeutics.

METHODS

We cultured hUC-MSCs with identical cell seeding densities in different formulations of SFM and SCM until passage 10 and examined the changes in cell phenotype and function. We analyzed the results with the commercial application requirments of the cellular therapy industry to assess the potential impact of customized culture media on inter-batch consistency, efficacy, stability, biosafety, and cost-effectiveness of industrial-scale cell production.

RESULTS

hUC-MSCs cultured in SCM and SFM exhibit consistent cell morphology and surface molecule expression, but hUC-MSCs cultured in SFM demonstrate higher activity, superior proliferative capacity, and greater stability. Furthermore, hUC-MSCs cultured in different SFM exhibit differences in cell activity, proliferative capacity, senescent rate, and S/M ratio of cell cycle, while maintaining a normal karyotype after long-term in vitro cultivation. Moreover, we found that hUC-MSCs cultured in different media exhibit variations in paracrine capacity and in their support of hematopoietic stem cell (HSC) self-renewal.

CONCLUSION

Considering the substantial funding and time required for cell-based drug development, our results underscore the importances of comprehensively optimizing the composition of medium for the specific disease prior to conducting clinical trials of cell-based therapies. The criteria for selecting culture medium should be based on the requirements of the target disease for cellular function. In addition, we provide a way to formulate different customized SFM, which is beneficial for the development of cell therapy industry.

Exploring Orthopedic Stem-Cell Approaches for Osteoarthritis Management: Current Trends and Future Horizons

PURPOSE OF REVIEW

Osteoarthritis (OA) is a prevalent and debilitating condition characterized by joint degeneration and pain. Current treatment options aim to alleviate symptoms and slow disease progression but lack curative potential. Stem cell therapies have emerged as a promising alternative. This article explores the epidemiology, pathophysiology, clinical manifestations of hip and knee OA, and the evolving role of stem cell therapies in their treatment.

RECENT FINDINGS

The global prevalence of OA, with knee OA being the most common form, has fueled the demand for stem cell therapies. Despite limited robust evidence supporting their efficacy, clinical trials investigating stem-cell treatments for OA have reported encouraging radiological and clinical improvements. Stem cell therapies offer potential disease-modifying benefits through immunomodulatory actions, growth factor secretion, and chondrogenic capabilities. Adipose-derived mesenchymal stem cells (ADMSCs) have shown promise in clinical trials for OA treatment, offering potential pain relief and functional improvement. ADMSCs possess advantages such as accessibility and a favorable safety profile, making them a viable option for OA management. Although other stem-cell types, including human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs), have been used in OA treatment, ADMSCs have demonstrated superior outcomes. By providing a comprehensive overview of the evolving landscape of stem cell therapies for hip and knee OA, this article highlights the potential of stem-cell treatments to address the limitations of current therapies. However, further research is required to establish their long-term efficacy, identify optimal stem-cell types, and develop standardized protocols.

Human umbilical cord mesenchymal stem cells promoting knee joint chondrogenesis for the treatment of knee osteoarthritis: a systematic review

PURPOSE

The onset of OA is affected by a variety of factors, which eventually lead to the loss of cartilage in the joints, the formation of osteophytes, the loss of normal knee mobility, and pain and discomfort, which seriously affects the quality of life. HUC-MSCs can promote cartilage production and have been widely used in research in the past decade. This article systematically summarizes that it is well used in basic research and clinical studies to promote inflammatory chondrogenesis in the treatment of OA. Provide a theoretical basis for clinical treatment.

PATIENTS AND METHODS

This study collected CNKI, Wanfang, PubMed, and articles related to the treatment of OA with HUC-MSCs since their publication, excluding non-basic and clinical studies such as reviews and meta-analysis. A total of 31 basic experimental studies and 12 clinical studies were included. Systematically analyze the effects of HUC-MSCs on inhibiting inflammatory factors, promoting chondrocyte production, and current clinical treatment.

RESULTS

HUC-MSCs can reduce inflammatory factors such as MMP-13, ADAMTS-5, IL-1β, IL-1, IL-6, TNF-α, induced conversion from M1 to M2 in OA to protect cartilage damage and reduce OA inflammation. Synthesize ColII, SOX9, and aggrecan at the same time to promote cartilage synthesis.

CONCLUSION

HUC-MSCs not only have typical stem cell biological characteristics, but also have rich sources and convenient material extraction. Compared with stem cells from other sources, HUC-MSCs have stronger proliferation, differentiation, and immune regulation abilities. Furthermore, there are no ethical issues associated with their use.

SAFETY

Primarily attributed to pain, the majority of individuals experience recovery within 24 h following injection. HUC-MSCs possess the ability to alleviate pain, enhance knee joint function, and potentially postpone the need for surgical intervention in both non-surgical and other cases, making them highly deserving of clinical promotion and application.

Cartilage Injury Repair by Human Umbilical Cord Wharton's Jelly/Hydrogel Combined with Chondrocyte

Purpose: There is still a lack of effective treatments for cartilage damage. Cartilage tissue engineering could be a promising treatment method. Human umbilical cord Wharton's jelly (HUCWJ) and hydrogels have received wide attention as a scaffold for tissue engineering. They have not been widely used in clinical studies as their effectiveness and safety are still controversial. This study systematically compared the ability of these two biological tissue engineering materials to carry chondrocytes to repair cartilage injury in vivo. Methods: Chondrocytes were cocultured with HUCWJ or hydrogel for in vivo transplantation. The treatments comprised the HUCWJ+cell, hydrogel+cell, and blank groups. A rabbit model with articular cartilage defect in the knee joint area was established. The defective knee cartilage of different rabbit groups was treated for 3 and 6 months. The efficacy of the various treatments on articular cartilage injury was evaluated by immunohistochemistry and biochemical indices. Results: We found that the HUCWJ+cell and hydrogel+cell groups promoted cartilage repair compared with the blank group, which had no repair effect. The treatment efficacy of each group at 6 months was significantly better than that at 3 months. HUCWJ showed accelerated cartilage repair ability than the hydrogel. Conclusion: This study showed that HUCWJ is useful in cartilage tissue engineering to enhance the efficacy of chondrocyte-based cartilage repair, providing new insights for regenerative medicine. Impact statement Human umbilical cord Wharton's jelly (HUCWJ) and hydrogel are the suitable extracellular matrix for cartilage tissue engineering. This study assessed the capacity of HUCWJ- and hydrogel-loaded chondrocytes to repair cartilage injury in vivo. The data demonstrate that both HUCWJ and hydrogel effectively facilitated cartilage repair, and the repair effects of HUCWJ were significantly better compared with hydrogel, therefore providing a potential candidate for clinical practice of cartilage regeneration therapy.

Immunomodulatory and Anti-inflammatory effect of Neural Stem/Progenitor Cells in the Central Nervous System

Neuroinflammation is a critical event that responds to disturbed homeostasis and governs various neurological diseases in the central nervous system (CNS). The excessive inflammatory microenvironment in the CNS can adversely affect endogenous neural stem cells, thereby impeding neural self-repair. Therapies with neural stem/progenitor cells (NSPCs) have shown significant inhibitory effects on inflammation, which is mainly achieved through intercellular contact and paracrine signalings. The intercellular contact between NSPCs and immune cells, the activated CNS- resident microglia, and astrocyte plays a critical role in the therapeutic NSPCs homing and immunomodulatory effects. Moreover, the paracrine effect mainly regulates infiltrating innate and adaptive immune cells, activated microglia, and astrocyte through the secretion of bioactive molecules and extracellular vesicles. However, the molecular mechanism involved in the immunomodulatory effect of NSPCs is not well discussed. This article provides a systematic analysis of the immunomodulatory mechanism of NSPCs, discusses efficient ways to enhance its immunomodulatory ability, and gives suggestions on clinical therapy.

Breakthrough of extracellular vesicles in pathogenesis, diagnosis and treatment of osteoarthritis

Osteoarthritis (OA) is a highly prevalent whole-joint disease that causes disability and pain and affects a patient's quality of life. However, currently, there is a lack of effective early diagnosis and treatment. Although stem cells can promote cartilage repair and treat OA, problems such as immune rejection and tumorigenicity persist. Extracellular vesicles (EVs) can transmit genetic information from donor cells and mediate intercellular communication, which is considered a functional paracrine factor of stem cells. Increasing evidences suggest that EVs may play an essential and complex role in the pathogenesis, diagnosis, and treatment of OA. Here, we introduced the role of EVs in OA progression by influencing inflammation, metabolism, and aging. Next, we discussed EVs from the blood, synovial fluid, and joint-related cells for diagnosis. Moreover, we outlined the potential of modified and unmodified EVs and their combination with biomaterials for OA therapy. Finally, we discuss the deficiencies and put forward the prospects and challenges related to the application of EVs in the field of OA.

Allogenic Umbilical Cord Tissue for Treatment of Knee Osteoarthritis

Interest in use of perinatal allogenic tissues including clinical-grade minimally manipulated umbilical cord tissue-derived allograft formulations to treat knee osteoarthritis (OA) patients is increasing. Limited studies have characterized these formulations and evaluated their safety and efficacy in knee OA patients. We developed such formulation and reported the presence of growth factors, cytokines, hyaluronic acid, and exosomes. We reported that its administration is safe, and resulted in 50% pain reduction and improvement in knee injury and osteoarthritis outcome score (over 10%) and 36-item short form survey (25%). Another study reported no adverse events post injection of similar formulation and statistically significant ( P <0.001) improvement in visual analog scale and Western Ontario and McMaster Universities Osteoarthritis Index scores and reduction in medication usage in patients (77.8%). We also summarized the clinical trials registered on ClinicalTrials.gov utilizing umbilical cord tissue for knee OA treatment. In conclusion, available studies are preliminary but pave the way to higher level appropriately powered investigations, and these formulations should be considered as nonoperative alternative to manage knee OA.

Allogenic perinatal tissue for musculoskeletal regenerative medicine applications: a systematic review protocol

BACKGROUND

Musculoskeletal ailments impact the lives of millions of people, and at times necessitate surgery followed by physiotherapy, drug treatments, or immobilization. Regenerative musculoskeletal medicine has undergone enormous progress over the last few decades. Sources of tissues used for regenerative medicine purposes can be grouped into autologous or allogenic. Although autologous sources are promising, there is a wide range of limitations with the treatment, including the lack of randomized controlled studies for orthopaedic conditions, donor site morbidity, and highly variable outcomes for patients. Allogenic sources bypass some of these shortcomings and are a promising source for orthopaedic regenerative medicine applications.

METHODS

A systematic search will be performed using PubMed, Elsevier, ScienceDirect, and Google Scholar databases for articles published in English before May 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and guidelines will be used. Studies will be eligible if they apply to acute and chronic orthopaedic musculoskeletal complications or animal or human disease models. Publications must include the use of MSCs and/or tissue obtained from amniotic/chorionic membrane, amniotic fluid, umbilical cord, and/or umbilical cord-derived Wharton's jelly as an intervention. Placebos, noninjury models, acute injury models, non-injury models, and gold standard treatments will be compared. The study selection will be performed by two independent reviewers using a dedicated reference management software. Data synthesis and meta-analysis will be performed separately for preclinical and clinical studies.

DISCUSSION

The results will be published in relevant peer-reviewed scientific journals. Investigators will present results at national or international conferences.

TRIAL REGISTRATION

The Protocol will be registered on PROSPERO international prospective register of systematic reviews prior to commencement.

Recent Biomimetic Approaches for Articular Cartilage Tissue Engineering and Their Clinical Applications: Narrative Review of the Literature

Since articular cartilage is lacking blood vessels and nerves, its capacity to heal is extremely limited. This means that ruptured cartilage affects the joint as a whole. A health issue known as osteoarthritis can develop as a result of injury and deterioration. Osteoarthritis development can be speeded up by the widespread deterioration of articular cartilage, which ranks third on the list of musculoskeletal disorders requiring rehabilitation, behind only low back pain and broken bones. The current treatments for cartilage repair are ineffective and rarely restore full function or tissue normalcy. A promising new technology in tissue engineering may help create functional cartilage tissue substitutes. Ensuring that the cell source is loaded with bioactive molecules that promote cellular differentiation and/or maturation is the general approach. This review summarizes recent advances in cartilage tissue engineering, and recent clinical trials have been conducted to provide a comprehensive overview of the most recent research developments and clinical applications in the framework of degenerated articular cartilage and osteoarthritis.

Allogenic Amniotic Tissue for Treatment of Knee and Hip Osteoarthritis

Osteoarthritis (OA) impacts millions of people and places a high burden on healthcare systems in the United States. Current treatment modalities have limitations and do not address underlying pathology. Lately, there has been an immense growth in the use of biologics, including perinatal allogenic tissues for orthopedic regenerative medicine applications. Amniotic tissue is an exciting new alternative for such applications. Despite several published studies that reported its use for treatment of ophthalmic conditions and complex wounds, there are limited clinical studies evaluating its safety and efficacy in treating patients suffering with knee or hip OA. In this manuscript, I focused on three prospective clinical studies which evaluated the safety and efficacy of amniotic tissue in patients suffering with moderate knee or hip OA. The results from these studies presented the scientific community with much needed, well-executed, and prospective clinical trials. Though these trials demonstrated that administration of amniotic tissue in knee or hip joint is safe and potentially effective, more multi-center, prospective, double-blinded, randomized controlled trials are warranted to further establish the efficacy of amniotic tissue to mitigate symptoms of knee and hip OA to ultimately justify its clinical use.

Exosomes in the Pathogenesis, Progression, and Treatment of Osteoarthritis

Osteoarthritis (OA) is a prevalent and debilitating age-related joint disease characterized by articular cartilage degeneration, synovial membrane inflammation, osteophyte formation, as well as subchondral bone sclerosis. OA drugs at present are mainly palliative and do not halt or reverse disease progression. Currently, no disease-modifying OA drugs (DMOADs) are available and total joint arthroplasty remains a last resort. Therefore, there is an urgent need for the development of efficacious treatments for OA management. Among all novel pharmaco-therapeutical options, exosome-based therapeutic strategies are highly promising. Exosome cargoes, which include proteins, lipids, cytokines, and various RNA subtypes, are potentially capable of regulating intercellular communications and gene expression in target cells and tissues involved in OA development. With extensive research in recent years, exosomes in OA studies are no longer limited to classic, mesenchymal stem cell (MSC)-derived vesicles. New origins, structures, and functions of exosomes are constantly being discovered and investigated. This review systematically summarizes the non-classic origins, biosynthesis, and extraction of exosomes, describes modification and delivery techniques, explores their role in OA pathogenesis and progression, and discusses their therapeutic potential and hurdles to overcome in OA treatment.

Antibacterial and Immunomodulatory Properties of Acellular Wharton’s Jelly Matrix

Of all biologic matrices, decellularized tissues have emerged as a promising tool in the field of regenerative medicine. Few empirical clinical studies have shown that Wharton’s jelly (WJ) of the human umbilical cord promotes wound closure and reduces wound-related infections. In this scope, we herein investigated whether decellularized (DC)-WJ could be used as an engineered biomaterial. In comparison with devitalized (DV)-WJ, our results showed an inherent effect of DC-WJ on Gram positive (S. aureus and S. epidermidis) and Gram negative (E. coli and P. aeruginosa) growth and adhesion. Although DC-WJ activated the neutrophils and monocytes in a comparable magnitude to DV-WJ, macrophages modulated their phenotypes and polarization states from the resting M0 phenotype to the hybrid M1/M2 phenotype in the presence of DC-WJ. M1 phenotype was predominant in the presence of DV-WJ. Finally, the subcutaneous implantation of DC-WJ showed total resorption after three weeks of implantation without any sign of foreign body reaction. These significant data shed light on the potential regenerative application of DC-WJ in providing a suitable biomaterial for tissue regenerative medicine and an ideal strategy to prevent wound-associated infections.

Current Advances in the Regeneration of Degenerated Articular Cartilage: A Literature Review on Tissue Engineering and Its Recent Clinical Translation

Functional ability is the basis of healthy aging. Articular cartilage degeneration is amongst the most prevalent degenerative conditions that cause adverse impacts on the quality of life; moreover, it represents a key predisposing factor to osteoarthritis (OA). Both the poor capacity of articular cartilage for self-repair and the unsatisfactory outcomes of available clinical interventions make innovative tissue engineering a promising therapeutic strategy for articular cartilage repair. Significant progress was made in this field; however, a marked heterogeneity in the applied biomaterials, biofabrication, and assessments is nowadays evident by the huge number of research studies published to date. Accordingly, this literature review assimilates the most recent advances in cell-based and cell-free tissue engineering of articular cartilage and also focuses on the assessments performed via various in vitro studies, ex vivo models, preclinical in vivo animal models, and clinical studies in order to provide a broad overview of the latest findings and clinical translation in the context of degenerated articular cartilage and OA.

Immunomodulatory extracellular vesicles: an alternative to cell therapy for COVID-19

Introduction: SARS-CoV-2 induces a cytokine storm and can cause inflammation, fibrosis and apoptosis in the lungs, leading to acute respiratory distress syndrome (ARDS). ARDS is the leading cause of mortality and morbidity the associated to COVID-19, and the cytokine storm is a prominent etiological factor. Mesenchymal stem cell-derived extracellular vesicles are an alternative therapy for the management of inflammatory and autoimmune conditions due to their immunosuppressive properties. The immunomodulatory and tissue regeneration capabilities of extracellular vesicles may support their application as a prospective therapy for COVID-19.Areas Covered: We explored the clinical evidence on extracellular vesicles as antiviral agents and in mitigating ARDS, and their therapeutic potential in COVID-19.Expert Opinion: Clinical trials using extracellular vesicles are registered against COVID-19 associated complications, with some evidence of safety and efficacy. Extracellular vesicles present an alternative potential for cell therapy for COVID-19 management, but further preclinical and clinical investigations are needed.

Hyaluronic acid hydrogel encapsulated BMP-14-modified ADSCs accelerate cartilage defect repair in rabbits

Background

Cartilage defect has a limited capacity to heal. In this context, we hypothesized that hyaluronic acid (HA) hydrogel encapsulated BMP-14-modified adipose-derived mesenchymal stem cells (ADSCs) could accelerate cartilage defect repair in rabbits.

Methods

ADSCs were isolated and identified by flow cytometry. ADSCs were treated with adenovirus vector encoding BMP-14 (Ad-BMP-14) or adenovirus vector encoding control (Ad-ctrl). Real-time PCR (RT-PCR) and western blot assay was performed to verify the transfection efficacy and chondrogenic differentiation markers (ACAN, Collagen II and SOX9). Rabbit cartilage defect model was performed and randomly divided into following groups: control group, HA hydrogel + ADSCs, ADSCs, HA hydrogel + BMP-14 transfected ADSCs, HA hydrogel + BMP-14 transfected ADSCs. At 6, 9 and 12 weeks after surgery, scanning electron microscopy, hematoxylin–eosin, Safranin-O/Fast Green and immunohistochemical staining for Collagen II were performed to determine the role of HA hydrogel encapsulated BMP-14-modified ADSCs in cartilage repair in vivo.

Results

ADSCs were successfully isolated and positively expressed CD29, CD44 and CD90. Transfection efficacy of Ad-BMP-14 was verified by RT-PCR and western blot assay. Moreover, Ad-BMP-14 could significantly increased chondrogenic differentiation markers (ACAN, Collagen II and SOX9). The LV-BMP-14-ADSCs and HA hydrogel + LV-BMP-14-ADSCs groups revealed smoother surface cartilage repair that was level with the surrounding cartilage and almost complete border integration.

Conclusions

HA hydrogel encapsulated BMP-14-modified ADSCs accelerate cartilage defect repair in rabbits. We need to further validate the specific mechanism of action of HA hydrogel encapsulated LV-BMP-14-ADSCs involved in the repairing cartilage damage in vivo.

Treatment of Knee Osteoarthritis with Intraarticular Umbilical Cord-Derived Wharton's Jelly: A Case Report

We present the case of a 27-year-old male with grade II knee osteoarthritis (OA) that was intraarticularly injected with a 2 mL umbilical cord-derived Wharton's jelly (UC-derived WJ) formulation. The patients' baseline radiographs were taken and baseline numeric pain rating scale (NPRS), knee injury and osteoarthritis outcome score (KOOS), 7-point Likert scale, and a 36-item short form survey (SF-36) were recorded. The NPRS was re-recorded immediately after the injection, and at 24 h, 48 h, 1 week, 6 weeks, and at 3 months follow-up post-injection. The KOOS and 7-point Likert scale was re-recorded at the patients' 1week, 6 week, and 3month follow-up, and SF-36 was re-recorded at 3 months. A final set of X-rays were also performed at 3 months follow-up post-injection. No adverse effects from the injection were reported over the duration of the study. No significant difference nor progression in OA on X-rays compared to baseline was observed. NPRS decreased by 50% and the 7-point Likert scale increased to Extremely Satisfied. KOOS increased overall by 10% and the SF-36 overall change was 25%. These results indicate the potential application of UC-derived WJ in the treatment of knee OA. Larger, long term, non-randomized and randomized control trials are warranted to adequately assess the safety and efficacy of UC-derived WJ and ultimate clinical use.

Cell-free stem cell-derived extract formulation for treatment of knee osteoarthritis: study protocol for a preliminary non-randomized, open-label, multi-center feasibility and safety study

BACKGROUND

Musculoskeletal conditions are highly prevalent, and knee OA is most common. Current treatment modalities have limitations and either fail to solve the underlying pathophysiology or are highly invasive. To address these limitations, attention has focused on the use of biologics. The efficacy of these devices is attributed to presence of growth factors (GFs), cytokines (CKs), and extracellular vesicles (EVs). With this in mind, we formulated a novel cell-free stem cell-derived extract (CCM) from human progenitor endothelial stem cells (hPESCs). A preliminary study demonstrated the presence of essential components of regenerative medicine, namely GFs, CKs, and EVs, including exosomes, in CCM. The proposed study aims to evaluate the safety and efficacy of intraarticular injection of the novel cell-free stem cell-derived extract (CCM) for the treatment of knee OA.

METHODS AND ANALYSIS

This is a non-randomized, open-label, multi-center, prospective study in which the safety and efficacy of intraarticular CCM in patients suffering from grade II/III knee OA will be evaluated. Up to 20 patients with grade II/III OA who meet the inclusion and exclusion criteria will be consented and screened to recruit 12 patients to receive treatment. The study will be conducted at up to 2 sites within the USA, and the 12 participants will be followed for 24 months. The study participants will be monitored for adverse reactions and assessed using Numeric Pain Rating Scale (NPRS), Patient-Reported Outcomes Measurement Information System (PROMIS) Score, Knee Injury and Osteoarthritis Outcome Score Jr. (KOOS Jr.), 36-ietm short form survey (SF-36), Single Assessment Numeric Evaluation (SANE), physical exams, plain radiography, and magnetic resonance imaging (MRI) with Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score for improvements in pain, function, satisfaction, and cartilage regeneration.

DISCUSSION

This prospective study will provide valuable information into the safety and efficacy of intraarticular administration of cell-free stem cell-derived extract (CCM) in patients suffering with grade II/III knee OA. The outcomes from this initial study of novel CCM will lay the foundation for a larger randomized, placebo-controlled, multi-center clinical trial of intraarticular CCM for symptomatic knee OA.

TRIAL REGISTRATION

Registered on July 21, 2021. ClinicalTrials.gov NCT04971798.