Mechanisms involved in the therapeutic properties of mesenchymal stem cells

Targeting oxidative stress in preeclampsia

Preeclampsia is a complex condition characterized by elevated blood pressure and organ damage involving kidneys or liver, resulting in significant morbidity and mortality for both the mother and the fetus. Increasing evidence suggests that oxidative stress, often caused by mitochondrial dysfunction within fetal trophoblast cells may play a major role in the development and progression of preeclampsia. Oxidative stress occurs as a result of an imbalance between the production of reactive oxygen species (ROS) and the capacity of antioxidant defenses, which can lead to placental cellular damage and endothelial cell dysfunction. Targeting oxidative stress appears to be a promising therapeutic approach that has the potential to improve both short- and long-term maternal and fetal outcomes, thus reducing the global burden of preeclampsia. The purpose of this review is to provide a comprehensive account of the mechanisms of oxidative stress in preeclampsia. Furthermore, it also examines potential interventions for reducing oxidative stress in preeclampsia, including natural antioxidant supplements, lifestyle modifications, mitochondrial targeting antioxidants, and pharmacological agents.A better understanding of the mechanism of action of proposed therapeutic strategies targeting oxidative stress is essential for the identification of companion biomarkers and personalized medicine approaches for the development of effective treatments of preeclampsia.

The revolutionary role of placental derivatives in biomedical research

The human placenta is a transient yet crucial organ that plays a key role in sustaining the relationship between the maternal and fetal organisms. Despite its historical classification as "biowaste," placental tissues have garnered increasing attention since the early 1900s for their significant medical potential, particularly in wound repair and surgical application. As ethical considerations regarding human placental derivatives have largely been assuaged in many countries, they have gained significant attention due to their versatile applications in various biomedical fields, such as biomedical engineering, regenerative medicine, and pharmacology. Moreover, there is a substantial trend toward various animal product substitutions in laboratory research with human placental derivatives, reflecting a broader commitment to advancing ethical and sustainable research methodologies. This review provides a comprehensive examination of the current applications of human placental derivatives, explores the mechanisms behind their therapeutic effects, and outlines the future potential and directions of this rapidly advancing field.

Quality by design strategy of human mesenchymal stem/stromal cell drug products for the treatment of knee osteoarthritis

Knee osteoarthritis (KOA), characterized by heterogeneous arthritic manifestations and complex peripheral joint disorder, is one of the leading causes of disability worldwide, which has become a high burden due to the multifactorial nature and the deficiency of available disease-modifying treatments. The application of mesenchymal stem/stromal cells (MSCs) as therapeutic drugs has provided novel treatment options for diverse degenerative and chronic diseases including KOA. However, the complexity and specificity of the “live” cells have posed challenges for MSC-based drug development and the concomitant scale-up preparation from laboratory to industrialization. For instance, despite the considerable progress in ex vivo cell culture technology for fulfilling the robust development of drug conversion and clinical trials, yet significant challenges remain in obtaining regulatory approvals. Thus, there’s an urgent need for the research and development of MSC drugs for KOA. In this review, we provide alternative solution strategies for the preparation of MSC drugs on the basis of the principle of quality by design, including designing the cell production processes, quality control, and clinical applications. In detail, we mainly focus on the quality by design method for MSC manufacturing in standard cell-culturing factories for the treatment of KOA by using the Quality Target Product Profile as a starting point to determine potential critical quality attributes and to establish relationships between critical material attributes and critical process parameters. Collectively, this review aims to meet product performance and robust process design, and should help to reduce the gap between compliant products and the production of compliant good manufacturing practice.

Advances in biomaterials and regenerative medicine for diabetic foot ulcer therapy

Diabetic foot ulcer (DFU), a severe complication of diabetes mellitus, presents significant clinical challenges due to its rapid deterioration and high morbidity rates. While conventional therapies exist kinds of limitations, their clinical utility is frequently constrained. Recent advancements in biomedical engineering have introduced innovative therapeutic modalities, particularly nanomaterials and hydrogels. However, emerging technologies face translational barriers including immature manufacturing processes leading to elevated costs, and insufficient long-term safety data due to limited clinical validation periods. Current clinical studies remain constrained by small cohort sizes and preliminary-stage investigations. The purpose of this study was to review traditional primary treatment and simultaneously combine clinical data to increase the speed of innovative safety, cost, and effectiveness indicator testing.

A sericin scaffold loaded with supernatant from mesenchymal stem cells exposed to pro-inflammatory cytokines enhances wound healing

Our previous research established that treatment with IFN-γ and TNF-α (IT) significantly enhanced the paracrine activity of MSCs, resulting in a more effective wound healing response when applied to the wound surface with supernatant from IT-stimulated MSCs (S-IT MSCs). While S-IT MSCs hold promise for advancing wound healing therapy, challenges remain in developing an approach that enhances therapeutic efficacy and simplifies administration. This study proposed a scaffold composed of sericin, known for its skin regeneration properties, to load S-IT MSCs, designated as Se + S-IT MSCs, for the protection of bioactive factors. Additionally, whether Se + S-IT MSCs exhibit a superior effect on wound healing was investigated using a rat total skin excision model. Results indicated that Se + S-IT MSCs outperformed silk sericin loaded with MSC supernatant (Se + S-MSCs) in promoting migration, proliferation, and activation of HUVECs, HaCaTs, macrophages, and HDFs. Furthermore, Se + S-IT MSCs significantly promoted macrophage polarization toward the M2 phenotype, potentiated vascularization and re-epithelialization, and enhanced collagen deposition. These effects collectively accelerated wound healing in vivo in rats. This study highlights the potential of Se + S-IT MSCs to facilitate rapid and effective wound healing, with silk sericin scaffolds serving as efficient carriers to expedite the process.

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.

Limbal stem cell deficiency approaches and limbal niche restoration

Approaches to limbal stem cell deficiency remain challenging, especially in bilateral cases, where healthy limbal stem cells are not accessible. While living-related allogeneic and allogeneic limbal stem cell sources have been utilized, their dependence on immunosuppression and its associated side effects pose significant limitations. Mucosal and mesenchymal stem cells have shown potential for differentiation into limbal stem cells and promoting corneal healing, primarily when cultured on the amniotic membrane or fibrin. However, none can fully replicate the original limbus. Innovations in surgical techniques, such as simple oral mucosal transplantation and subconjunctival or intrastromal mesenchymal stem cell injections, are emerging approaches. For successful limbal regeneration, both appropriate cells and suitable scaffolds are essential. Recent studies on decellularized and acellularized limbus models have demonstrated the potential to provide a three-dimensional native structure for cell seeding, retention, and differentiation. Creating a thin, evenly decellularized scaffold is a critical step in ensuring proper corneo-limbal slope formation, facilitating cell migration to the ocular surface. Harvesting the limbus, decellularization, and cell seeding are the three main steps in limbal reconstruction. Recent studies focus on microkeratome-assisted limbal harvesting to create a thin, even, and 360-degree limbal graft. This technique helps form an attached corneo-limbal interface, facilitating limbal stem cell migration. In the second step, acellularization is performed to preserve the extracellular matrix as much as possible, maintaining hemostasis and supporting paracrine interactions. The final steps involve recellularization and transplantation onto the eye. We summarize various limbal decellularization methods, their outcomes, and their potential in limbal reconstruction. More clinical studies are needed to validate this phase of limbal deficiency treatment.

The Current Status and Future Prospects of Intra-articular Injection Therapy for Hip Osteoarthritis: A Review

PURPOSE OF REVIEW

Hip osteoarthritis constitutes a prevalent condition among individuals aged 55 and above, serving as one of the primary triggers for joint discomfort and impairment, and marking a substantial origin of chronic pain particularly affecting the elderly population. Our article provides an exhaustive summary of the mechanisms of action, therapeutic efficacy, and potential adverse consequences associated with novel therapeutic modalities including glucocorticoids, hyaluronic acid, platelet-rich plasma, mesenchymal stem cells, and stromal vascular fraction. Concurrently, we conducted a comprehensive evaluation of the clinical efficacy and potential applications of various medications.

RECENT FINDINGS

In comparison to physical therapy, oral analgesics, and other nonsurgical modalities, intra-articular injection therapy is characterized by enhanced safety and greater efficacy. Moreover, when contrasted with surgical intervention, intra-articular injection demonstrates a lower degree of invasiveness and incurs fewer adverse reactions. Intra-articular treatments have shown excellent local efficacy while significantly minimizing adverse reactions in patients. These methods hold significant potential for development but require comprehensive research and thorough discussion within the academic community.

The Regenerative Marriage Between High-Density Platelet-Rich Plasma and Adipose Tissue

The use of autologous biological preparations (ABPs) and their combinations fills the void in healthcare treatment options that exists between surgical procedures, like plastic reconstructive, cosmetic, and orthopedic surgeries; non-surgical musculoskeletal biological procedures; and current pharmaceutical treatments. ABPs, including high-density platelet-rich plasma (HD-PRP), bone marrow aspirate concentrates (BMACs), and adipose tissue preparations, with their unique stromal vascular fractions (SVFs), can play important roles in tissue regeneration and repair processes. They can be easily and safely prepared at the point of care. Healthcare professionals can employ ABPs to mimic the classical wound healing cascade, initiate the angiogenesis cascade, and induce tissue regenerative pathways, aiming to restore the integrity and function of damaged tissues. In this review, we will address combining autologous HD-PRP with adipose tissue, in particular the tissue stromal vascular fraction (t-SVF), as we believe that this biocellular combination demonstrates a synergistic effect, where the HD-PRP constituents enhance the regenerative potential of t-SVF and its adipose-derived mesenchymal stem cells (AD-MSCs) and pericytes, leading to improved functional tissue repair, tissue regeneration, and wound healing in variety of clinical applications. We will address some relevant platelet bio-physiological aspects, since these properties contribute to the synergistic effects of combining HD-PRP with t-SVF, promoting overall better outcomes in chronic inflammatory conditions, soft tissue repair, and tissue rejuvenation.

Effect of Hyaluronic Acid Compared to Platelet-Rich Plasma as Adjuvants to Bone Marrow Mesenchymal Stem Cell Treatment of Knee Osteoarthritis: Analysis from Two Clinical Trials

Background: Bone marrow mesenchymal stem cell (BM-MSC) therapy has emerged as a safe and feasible treatment option for patients with knee osteoarthritis (OA). However, the role of adjuvants remains unclear. Our aim was to evaluate the clinical and radiological effects of hyaluronic acid (HA) in comparison to platelet-rich plasma (PRP) as adjuvants to 100 × 106 BM-MSCs in the treatment of knee OA. Methods: We used data from two randomized, parallel-group and controlled clinical trials which tested the efficacy of BM-MSC, previously published in 2016 (Clinical Trials.gov identifier NCT02123368, Nº EudraCT: 2009-017624-72) and 2020 (Clinical Trials.gov identifier NCT02365142. Nº EudraCT: 2011-006036-23). Results: Of the 34 patients included in the study, 24 had received 100 × 106 BM-MSCs plus PRP and 10 had received 100 × 106 BM-MSCs plus HA. On average, BM-MSC plus HA showed a higher improvement in VAS for pain [β-coefficient: -1.25; 95% confidence interval (95% CI):-2.20 to -0.30) than BM-MSC plus PRP (p = 0.01). We also observed that BM-MSC plus HA showed a greater improvement in all the WOMAC subscales scores and in the WOMAC overall score, compared to BM-MSC plus PRP, although these differences were not statistically significant. The Whole-Organ Magnetic Resonance Imaging Score (WORMS) at 12 months was more beneficial with 100 × 106 BM-MSCs plus HA (β-coefficient: -12.61; 95% CI: -19.71, -5.52) than with BM-MSC plus PRP (p = 0.001). Conclusions: The clinical and radiological outcomes after BM-MSC therapy for knee OA could differ according to the adjuvant employed. HA showed greater clinical effectiveness and fewer instances of articular degeneration than PRP as an adjuvant.

Stem Cell Therapy for Diseases of Livestock Animals: An In-Depth Review

Stem cells are unique, undifferentiated cells that have the ability to both replicate themselves and develop into specialized cell types. This dual capability makes them valuable in the development of regenerative medicine. Current development in stem cell research has widened their application in cell therapy, drug discovery, reproductive cloning in animals, and cell models for various diseases. Although there are substantial studies revealing the treatment of human degenerative diseases using stem cells, this is yet to be explored in livestock animals. Many diseases in livestock species such as mastitis, laminitis, neuromuscular disorders, autoimmune diseases, and some debilitating diseases are not covered completely by the existing drugs and treatment can be improved by using different types of stem cells like embryonic stem cells, adult stem cells, and induced pluripotent stem cells. This review mainly focuses on the use of stem cells for disease treatment in livestock animals. In addition to the diseases mentioned, the potential of stem cells can be helpful in wound healing, skin disease therapy, and treatment of some genetic disorders. This article explores the potential of stem cells from various sources in the therapy of livestock diseases and also their role in the conservation of endangered species as well as disease model preparation. Moreover, the future perspectives and challenges associated with the application of stem cells in livestock are discussed. Overall, the transformative impact of stem cell research on the livestock sector is comprehensively studied which will help researchers to design future research work on stem cells related to livestock diseases.

The Multifaceted Roles of MicroRNA-181 in Stem Cell Differentiation and Cancer Stem Cell Plasticity

Stem cells are undifferentiated or partially differentiated cells with an extraordinary ability to self-renew and differentiate into various cell types during growth and development. The epithelial-mesenchymal transition (EMT), a critical developmental process, enhances stem cell-like properties in cells, and is associated with both normal stem cell function and the formation of cancer stem cells. Cell stemness and the EMT often coexist and are interconnected in various contexts. Cancer stem cells are a critical tumor cell population that drives tumorigenesis, cancer progression, drug resistance, and metastasis. Stem cell differentiation and the generation of cancer stem cells are regulated by numerous molecules, including microRNAs (miRNAs). These miRNAs, particularly through the modulation of EMT-associated factors, play major roles in controlling the stemness of cancer stem cells. This review presents an up-to-date summary of the regulatory roles of miR-181 in human stem cell differentiation and cancer cell stemness. We outline studies from the current literature and summarize the miR-181-controlled signaling pathways responsible for driving human stem cell differentiation or the emergence of cancer stem cells. Given its critical role in regulating cell stemness, miR-181 is a promising target for influencing human cell fate. Modulation of miR-181 expression has been found to be altered in cancer stem cells' biological behaviors and to significantly improve cancer treatment outcomes. Additionally, we discuss challenges in miRNA-based therapies and targeted delivery with nanotechnology-based systems.

Mesenchymal stem cell therapy as a game-changer in liver diseases: review of current clinical trials

Chronic liver diseases, including cirrhosis and liver failure, remain formidable challenges due to their complex progression and limited therapeutic options. Mesenchymal stem cell (MSC) therapy has emerged as a game-changing approach, leveraging its potent immunomodulatory, anti-fibrotic, and regenerative capabilities, along with the ability to transdifferentiate into hepatocytes. This review delves into the latest advances in MSC-based treatments for chronic and end-stage liver diseases, as highlighted in current clinical trials. MSCs derived from bone marrow and umbilical cord have shown remarkable promise in reversing liver damage, improving liver function, and providing hope for patients who do not respond to conventional therapies. When administered through hepatic, portal, or peripheral veins, MSCs have significantly improved liver histology, reduced fibrosis, and restored functional capacity. Furthermore, MSC-derived materials, such as extracellular vesicles and exosomes, are emerging as cutting-edge tools for treating liver failure and mitigating post-transplant complications. While autologous MSC-derived hepatocytes hold promise for non-fatal cirrhosis, allogeneic MSCs are being applied in more severe conditions, including liver failure and transplantation cases. Despite these promising early outcomes, larger trials and long-term studies are essential to fully harness MSCs as a transformative, off-the-shelf alternative to liver transplantation, heralding a new era in regenerative liver therapies.

Mesenchymal Stem Cells in Cancer Therapy

The mesenchymal stem/stromal cells (MSCs) are multipotent cells that were initially discovered in the bone marrow in the late 1960s but have so far been discovered in almost all tissues of the body. The multipotent property of MSCs enables them to differentiate into various cell types and lineages, such as adipocytes, chondrocytes, and osteocytes. The immunomodulation capacity and tumor-targeting features of MSCs made their use crucial for cell-based therapies in cancer treatment, yet limited advancement could be observed in translational medicine prospects due to the need for more information regarding the controversial roles of MSCs in crosstalk tumors. In this review, we discuss the therapeutic potential of MSCs, the controversial roles played by MSCs in cancer progression, and the anticancer therapeutic strategies that are in association with MSCs. Finally, the clinical trials designed for the direct use of MSCs for cancer therapy or for their use in decreasing the side effects of other cancer therapies are also mentioned in this review to evaluate the current status of MSC-based cancer therapies.

Exploring the dichotomy of the mesenchymal stem cell secretome: Implications for tumor modulation via cell-signaling pathways

Current cancer therapeutic strategies for the treatment of cancer are often unsuccessful due to unwanted side effects and drug resistance. Therefore, the design and development of potent, new anticancer platforms, such as stem-cell treatments, have attracted much attention. Distinctive biological properties of stem cells include their capacity to secrete bioactive factors, their limited immunogenicity, and their capacity for renewing themselves. Mesenchymal stem cells (MSCs) are one of several kinds of stem cells that are conveniently extracted and are able to be cultivated in vitro utilizing various sources. The secretome of stem cells contains many trophic factors, including cytokines, chemokines, growth factors, and microRNA molecules that can either promote or inhibit the formation of tumors, based on the cell environment. In the current review, we focused on the secretome of mesenchymal stem cells. These stem cells act as a double-edged sword in the regulation of cell signal transduction pathways in that they can either suppress or promote tumors.

Mesenchymal Stem Cells and Their Extracellular Vesicles: Therapeutic Mechanisms for Blood-Spinal Cord Barrier Repair Following Spinal Cord Injury

Spinal cord injury (SCI) disrupts the blood-spinal cord barrier (BSCB) exacerbating damage by allowing harmful substances and immune cells to infiltrate spinal neural tissues from the vasculature. This leads to inflammation, oxidative stress, and impaired axonal regeneration. The BSCB, essential for maintaining spinal cord homeostasis, is structurally similar to the blood-brain barrier. Its restoration is a key therapeutic target for improving outcomes in SCI. Mesenchymal stromal/stem cells (MSCs) and their secreted extracellular vesicles (MSC-EVs) have gained attention for their regenerative, immunomodulatory, and anti-inflammatory properties in promoting BSCB repair. MSCs enhance BSCB integrity by improving endothelial-pericyte association, restoring tight junction proteins, and reducing inflammation. MSC-EVs, which deliver bioactive molecules, replicate many of MSCs' therapeutic effects, and offer a promising cell-free alternative. Preclinical studies have shown that both MSCs and MSC-EVs can reduce BSCB permeability, promote vascular stability, and support functional recovery. While MSC therapy is advancing in clinical trials, MSC-EV therapies require further optimization in terms of production, dosing, and delivery protocols. Despite these challenges, both therapeutic approaches represent significant potential for treating SCI by targeting BSCB repair and improving patient outcomes.

Global requirements for manufacturing and validation of clinical grade extracellular vesicles

Extracellular vesicles (EVs) are nanovesicles released from different cell types from biofluids such as blood, urine, and cerebrospinal fluid. They vary in size and biomarkers, and their biogenesis pathways allow them to be divided into three major types: exosomes, micro-vesicles, and apoptotic bodies. EVs have been studied in the context of diagnosis and therapeutic intervention of various pathological conditions such as cancer, neurodegenerative diseases, and pulmonary diseases. However, the production of EV-based therapeutics can be affected by the source, heterogeneity, or disease, raising questions about the manufacturing and validation of EVs of clinical grade and their scope regarding good manufacturing practice (GMP) in the industry. To address this, we have discussed the state-of-the-art requirements for EV production that must occur in a GMP-compliant environment with a reliable and traceable source. Additionally, EVs' homogeneity and the therapeutics' purity and stability must be analyzed and validated. Quality control measures must also be established to ensure the safety and efficacy of EVs. In conclusion, these considerations must be weighed carefully when manufacturing and validating EVs of clinical grade to ensure their safety and efficacy for therapeutic use.

Efficacy of mesenchymal stem cells in the treatment of peritoneal fibrosis in animal models: a systematic review and meta-analysis

BACKGROUND

Peritoneal fibrosis is a serious complication of long-term peritoneal dialysis, often resulting in functional deterioration and withdrawal from therapy. Mesenchymal stem cells (MSCs) have demonstrated immunomodulatory and antifibrotic effects in various models. This meta-analysis evaluated the efficacy of MSCs therapy in animal models of peritoneal fibrosis.

METHODS

A comprehensive search of PubMed, the Cochrane Library, Web of Science, and EMBASE was conducted for studies published up to April 27, 2024. Two independent reviewers (LQZ and WMC) screened studies for inclusion, extracted data, and analyzed outcomes using RevMan 5.3 and STATA 17.0.

RESULT

Fifteen studies met the inclusion criteria. MSC therapy significantly reduced inflammatory cytokines, including IL-6, TGF-β (SMD = -1.79, 95% CI: -2.32, -1.25, p < 0.00001), and TNF-α (SMD = -1.57, 95% CI: -2.71, -0.44, p = 0.006) levels. Additionally, MSCs reduced submesothelial thickness (MD = -63.14, 95% CI: -78.52, -47.76, p < 0.00001), Collagen I and Collagen III levels. MSCs treatment also improved ultrafiltration capacity (MD = 1.21, 95% CI: 0.64, 1.77, p < 0.0001), D/D0 of glucose and E-cadherin levels. However, no significant differences were observed in VEGF, D/P of Na, D/P of BUN, D/P of protein, or glucose mass transfer between the MSCs treatment group and the control group.

CONCLUSION

MSC therapy significantly improves peritoneal function and attenuates fibrotic and inflammatory responses in animal models. These findings highlight the potential of MSCs as a promising therapeutic strategy for managing peritoneal fibrosis in clinical settings.

Generating suspension-adapted human mesenchymal stromal cells (S-hMSCs) for the scalable manufacture of extracellular vesicles

BACKGROUD

Human mesenchymal stromal cells (hMSCs) are a naturally adherent cell type and one of the most studied cellular agents used in cell therapy over the last 20 years. Their mechanism of action has been primarily associated with paracrine signaling, which has contributed to an increase in the number of studies focused on hMSC-related extracellular vesicles (EVs).

METHODS

In this study, we demonstrate for the first time that human telomerase reverse transcriptase (hTERT) immortalized hMSCs can be adapted to suspension culture, eliminating the need for microcarriers or other matrixes to support cell growth.

RESULTS

This novel cell line, named suspension hMSCs (S-hMSCs), has a doubling time of approximately 55 hours, with a growth rate of 0.423/d. Regarding its immunophenotype characteristics, S-hMSCs retained close to 90% of CD73 and CD105 expression levels, with the CD90 receptor being downregulated during the adherent to suspension adaptation process. An RNA sequencing analysis showed an upregulation of the transcripts coding for CD44, CD46 and CD47 compared to the expression levels in AT-hMSCs and hTERT-hMSCs. The cell line herein established was able to generate EVs using a chemically defined medium formulation with these nanoparticles averaging 150 nm in size and displaying the markers CD63, CD81, and TSG101, while not expressing the negative marker calnexin.

CONCLUSION

This body of evidence, combined with the visual confirmation of EV presence using transmission electron microscopy, demonstrates the EV-producing capabilities of the novel S-hMSCs. This cell line provides a platform for process development, drug discovery and translational studies in the EV field.

Effects of Late-Passage Small Umbilical Cord-Derived Fast Proliferating Cells on Tenocytes from Degenerative Rotator Cuff Tears under an Interleukin 1β-Induced Tendinopathic Environment

BACKGROUND

Tendinopathy is a chronic tendon disease. Mesenchymal stem cells (MSCs), known for their anti-inflammatory properties, may lose effectiveness with extensive culturing. Previous research introduced "small umbilical cord-derived fast proliferating cells" (smumf cells), isolated using a novel minimal cube explant method. These cells maintained their MSC characteristics through long-term culture. Thus, the purpose of the present study was to assess the anti-inflammatory effects of late-passage smumf cells at P10 on tenocytes derived from degenerative rotator cuff tears in a tendinopathic environment.

METHODS

The mRNA expression with respect to aging of MSCs and secretion of growth factors (GFs) by smumf cells at P10 were measured. mRNA and protein synthesis in tenocytes with respect to the tenocyte phenotype, inflammatory cytokines, and matrix- degradation enzymes were measured. The inflammatory signal pathways involving nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) in tenocytes were also investigated. The proliferative response of degenerative tenocytes to co-culture with smumf cells over 7 days in varying IL-1β induced tendinopathic environments was investigated.

RESULTS

smumf cells at P10 showed no signs of aging compared to those at P3. smumf cells at P10, secreting 2,043 pg/ml of hepatocyte growth factor (HGF), showed a 1.88-fold (p = .002) increase in HGF secretion in a tendinopathic environment. Degenerative tenocytes co-cultured with smumf cells showed significantly increased protein expression levels of collagen type I (Col I) and the Col I/III ratio by 1.46-fold (p < .001) and 1.66-fold (p < .001), respectively. The smumf cells at P10 reduced both mRNA and protein expression levels of matrix metalloproteinases-1, -2, -3, -8, -9, and -13 in tenocytes and attenuated NF-κB (phosphorylated IκBα/IκBα and phosphorylated p65/p65) and MAPK (phosphorylated p38/p38 and phosphorylated JNK/JNK) pathways activated by IL-1β. Removal of IL-1β from the co-culture accelerated the growth of tenocytes by 1.42-fold (p < .001). Removal of IL-1β accelerated tenocyte growth in co-cultures.

CONCULSION

Late-passage smumf cells exert anti-inflammatory effects on tenocytes derived from degenerative rotator cuff tears under a tendinopathic environment, primarily through the secretion of growth factors (GFs).

Mesenchymal stem cell application in pulmonary disease treatment with emphasis on their interaction with lung-resident immune cells

Due to the vital importance of the lungs, lung-related diseases and their control are very important. Severe inflammatory responses mediated by immune cells were among the leading causes of lung tissue pathology and damage during the COVID-19 pandemic. In addition, uncontrolled immune cell responses can lead to lung tissue damage in other infectious and non-infectious diseases. It is essential to control immune responses in a way that leads to homeostasis. Immunosuppressive drugs only suppress inflammatory responses and do not affect the homeostasis of reactions. The therapeutic application of mesenchymal stem cells (MSCs), in addition to restoring immune homeostasis, can promote the regeneration of lung tissue through the production of growth factors and differentiation into lung-related cells. However, the communication between MSCs and immune cells after treatment of pulmonary diseases is essential, and investigating this can help develop a clinical perspective. Different studies in the clinical phase showed that MSCs can reverse fibrosis, increase regeneration, promote airway remodeling, and reduce damage to lung tissue. The proliferation and differentiation potential of MSCs is one of the mechanisms of their therapeutic effects. Furthermore, they can secrete exosomes that affect the function of lung cells and immune cells and change their function. Another important mechanism is that MSCs reduce harmful inflammatory responses through communication with innate and adaptive immune cells, which leads to a shift of the immune system toward regulatory and hemostatic responses.

Bioinspired injectable hydrogels for bone regeneration

The effective regeneration of bone/cartilage defects remains a significant clinical challenge, causing irreversible damage to millions annually.Conventional therapies such as autologous or artificial bone grafting often yield unsatisfactory outcomes, emphasizing the urgent need for innovative treatment methods. Biomaterial-based strategies, including hydrogels and active scaffolds, have shown potential in promoting bone/cartilage regeneration. Among them, injectable hydrogels have garnered substantial attention in recent years on account of their minimal invasiveness, shape adaptation, and controlled spatiotemporal release. This review systematically discusses the synthesis of injectable hydrogels, bioinspired approaches-covering microenvironment, structural, compositional, and bioactive component-inspired strategies-and their applications in various bone/cartilage disease models, highlighting bone/cartilage regeneration from an innovative perspective of bioinspired design. Taken together, bioinspired injectable hydrogels offer promising and feasible solutions for promoting bone/cartilage regeneration, ultimately laying the foundations for clinical applications. Furthermore, insights into further prospective directions for AI in injectable hydrogels screening and organoid construction are provided.

Redox signaling regulates the skeletal tissue development and regeneration

Skeletal tissue development and regeneration in mammals are intricate, multistep, and highly regulated processes. Various signaling pathways have been implicated in the regulation of these processes, including redox. Redox signaling is the signal transduction by electron transfer reactions involving free radicals or related species. Redox homeostasis is essential to cell metabolic states, as the ROS not only regulates cell biological processes but also mediates physiological processes. Following a bone fracture, redox signaling is also triggered to regulate bone healing and regeneration by targeting resident stromal cells, osteoblasts, osteoclasts and endothelial cells. This review will focus on how the redox signaling impact the bone development and bone regeneration.

Therapeutic potential of mesenchymal stem cell-derived extracellular vesicles: A focus on inflammatory bowel disease

BACKGROUND

Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as key regulators of intercellular communication, orchestrating essential biological processes by delivering bioactive cargoes to target cells. Available evidence suggests that MSC-EVs can mimic the functions of their parental cells, exhibiting immunomodulatory, pro-regenerative, anti-apoptotic, and antifibrotic properties. Consequently, MSC-EVs represent a cell-free therapeutic option for patients with inflammatory bowel disease (IBD), overcoming the limitations associated with cell replacement therapy, including their non-immunogenic nature, lower risk of tumourigenicity, cargo specificity and ease of manipulation and storage.

MAIN TOPICS COVERED

This review aims to provide a comprehensive examination of the therapeutic efficacy of MSC-EVs in IBD, with a focus on their mechanisms of action and potential impact on treatment outcomes. We examine the advantages of MSC-EVs over traditional therapies, discuss methods for their isolation and characterisation, and present mechanistic insights into their therapeutic effects through transcriptomic, proteomic and lipidomic analyses of MSC-EV cargoes. We also discuss available preclinical studies demonstrating that MSC-EVs reduce inflammation, promote tissue repair and restore intestinal homeostasis in IBD models, and compare these findings with those of clinical trials.

CONCLUSIONS

Finally, we highlight the potential of MSC-EVs as a novel therapy for IBD and identify challenges and opportunities associated with their translation into clinical practice.

HIGHLIGHTS

The source of mesenchymal stem cells (MSCs) strongly influences the composition and function of MSC-derived extracellular vesicles (EVs), affecting their therapeutic potential. Adipose-derived MSC-EVs, known for their immunoregulatory properties and ease of isolation, show promise as a treatment for inflammatory bowel disease (IBD). MicroRNAs are consistently present in MSC-EVs across cell types and are involved in pathways that are dysregulated in IBD, making them potential therapeutic agents. For example, miR-let-7a is associated with inhibition of apoptosis, miR-100 supports cell survival, miR-125b helps suppress pro-inflammatory cytokines and miR-20 promotes anti-inflammatory M2 macrophage polarisation. Preclinical studies in IBD models have shown that MSC-EVs reduce intestinal inflammation by suppressing pro-inflammatory mediators (e.g., TNF-α, IL-1β, IL-6) and increasing anti-inflammatory factors (e.g., IL-4, IL-10). They also promote mucosal healing and strengthen the integrity of the gut barrier, suggesting their potential to address IBD pathology.

Biomimetic Tissue Engineering Strategies for Craniofacial Applications

Biomimetics is the science of imitating nature's designs and processes to create innovative solutions for various fields, including dentistry and craniofacial reconstruction. In these areas, biomimetics involves drawing inspiration from living organisms/systems to develop new materials, techniques, and devices that closely resemble natural tissue structures and enhance functionality. This field has successfully demonstrated its potential to revolutionize craniofacial procedures, significantly improving patient outcomes. In dentistry, biomimetics offers exciting possibilities for the advancement of new dental materials, restorative techniques, and regenerative potential. By analyzing the structure/composition of natural teeth and the surrounding tissues, researchers have developed restorative materials that mimic the properties of teeth, as well as regenerative techniques that might assist in repairing enamel, dentin, pulp, cementum, periodontal ligament, and bone. In craniofacial reconstruction, biomimetics plays a vital role in developing innovative solutions for facial trauma, congenital defects, and various conditions affecting the maxillofacial region. By studying the intricate composition and mechanical properties of the skull and facial bones, clinicians and engineers have been able to replicate natural structures leveraging computer-aided design and manufacturing (CAD/CAM) and 3D printing. This has allowed for the creation of patient-specific scaffolds, implants, and prostheses that accurately fit a patient's anatomy. This review highlights the current evidence on the application of biomimetics in the fields of dentistry and craniofacial reconstruction.

Molecular and Cellular Mechanisms of the Therapeutic Effect of Mesenchymal Stem Cells and Extracellular Vesicles in Corneal Regeneration

The cornea is a vital component of the visual system, and its integrity is crucial for optimal vision. Damage to the cornea resulting from trauma, infection, or disease can lead to blindness. Corneal regeneration using mesenchymal stem cells (MSCs) and MSC-derived extracellular vesicles (MSC-EVs) offers a promising alternative to corneal transplantation. MSCs are multipotent stromal cells that can differentiate into various cell types, including corneal cells. They can also secrete a variety of anti-inflammatory cytokines and several growth factors, promoting wound healing and tissue reconstruction. This review summarizes the current understanding of the molecular and cellular mechanisms by which MSCs and MSC-EVs contribute to corneal regeneration. It discusses the potential of MSCs and MSC-EV for treating various corneal diseases, including corneal epithelial defects, dry eye disease, and keratoconus. The review also highlights finalized human clinical trials investigating the safety and efficacy of MSC-based therapy in corneal regeneration. The therapeutic potential of MSCs and MSC-EVs for corneal regeneration is promising; however, further research is needed to optimize their clinical application.

Definition of Synovial Mesenchymal Stem Cells for Meniscus Regeneration by the Mechanism of Action and General Amp1200 Gene Expression

The quality control (QC) of pharmaceutical-grade cell-therapy products, such as mesenchymal stem cells (MSCs), is challenging. Attempts to develop such products have been hampered by difficulties defining cell-type-specific characteristics and therapeutic mechanisms of action (MoAs). Although we have developed a cell therapy product, FF-31501, consisting of human synovial MSCs (SyMSCs), it was difficult to find specific markers for SyMSCs and to define the cells separately from other MSCs. The purpose of this study was to create a method for identifying and defining SyMSCs from other tissue-derived MSCs and to delve deeper into the mechanism of action of SyMSC-induced meniscus regeneration. Specifically, as a cell-type-dependent approach, we constructed a set of 1143 genes (Amp1200) reported to be associated with MSCs and established a method to evaluate them by correlating gene expression patterns. As a result, it was possible to define SyMSCs separately from other tissue-derived MSCs and non-MSCs. In addition, the gene expression analysis also highlighted TNSF-15. The in vivo rat model of meniscus injury found TNSF-15 to be an essential molecule for meniscus regeneration via SyMSC administration. This molecule and previously reported MoA molecules allowed an MoA-dependent approach to define the mechanism of action for SyMSCs. Therefore, SyMSCs for meniscus regeneration were defined by means of two approaches: the method to separate them from other MSCs and the identification of the MoA molecules. These approaches would be useful for the QC of cell therapy products.

Efficacy of a Single Injection of Stromal Vascular Fraction in Dogs with Elbow Osteoarthritis: A Clinical Prospective Study

This study aimed to assess the efficacy of a single intra-articular injection of autologous stromal vascular fraction (SVF) in dogs with chronic lameness due to advanced elbow osteoarthritis (OA) that were unresponsive to conventional drug therapy. In this clinical, prospective, non-blinded, single-center study, twenty-three dogs received autologous SVF derived from falciform adipose tissue. Primary outcome measures over the six-month study period included clinical-orthopedic and radiographic examinations, objective gait analysis and validated owner questionnaires. In 19 of 23 joints, no progression of OA was visible radiographically. Peak vertical force improved significantly at three months and vertical impulse at six months after the injection compared to baseline. Over 33% of dogs demonstrated treatment-related improvements in lameness based on objective gait analysis. Owner questionnaires indicated significant improvement in clinical signs throughout the study period and 26% of dogs showed treatment-related improvements in pain scores according to the Canine Brief Pain Inventory. No side effects were reported. These findings suggest that autologous regenerative cell therapy may provide a promising treatment option for dogs with advanced OA that do not respond to conventional drug therapy. However, the treatment did not improve the clinical symptoms in all dogs, so it cannot be recommended for all patients.

Ultrasound-targeted microbubble destruction facilitates cartilage repair through increased the migration of mesenchymal stem cells via HIF-1α-mediated glycolysis pathway in rats

OBJECTIVE

Mesenchymal stem cells (MSCs) can treat osteoarthritis (OA), but their therapeutic efficacy is poor to date due to low migration efficiency. This study aimed to determine whether ultrasound-targeted microbubble destruction (UTMD) could ameliorate cartilage repair efficiency through facilitating the migration of MSCs via hypoxia-inducible factor-1α (HIF-1α)-mediated glycolysis regulatory pathway in OA model rats.

METHODS

OA rats were treated with MSCs alone or in combination with UTMD, respectively, for 4 weeks. Cartilage histopathology, MSCs migration efficiency, von Frey fiber thresholds, and the expression levels of collagen II and MMP-13 were measured. Further, MSCs were extracted from the bone marrow of rats, cocultured with osteoarthritic chondrocytes, transfected to siRNA-HIF-1α, and subjected to UTMD for 4 days. Glucose consumption, lactate production, and cell migration efficiency were assessed. The protein expression levels of HIF-1α, HK2, PKM2, and GLUT1 were measured, respectively.

RESULTS

In OA rat model, NC-MSCs + UTMD improved migration efficiency, increased collagen II expression, decreased MMP-13 expression, and delayed osteoarthritis progression. Silencing HIF-1α attenuated the effects induced by UTMD. In vitro, UTMD led to increases in MSC activity and migration, glucose consumption, lactate production, and the protein expression of HIF-1α, HK2, PKM2, and GLUT1 expression, all of which were reversed upon HIF-1α silencing.

CONCLUSION

UTMD enhances MSCs migration and improves cartilage repair efficiency through the HIF-1α-mediated glycolytic regulatory pathway, providing a novel therapy strategy for knee osteoarthritis.

Single-Cell RNA Sequencing Reveals Repair Features of Human Umbilical Cord Mesenchymal Stromal Cells

Rationale: The chronic lung disease bronchopulmonary dysplasia (BPD) is the most severe complication of extreme prematurity. BPD results in impaired lung alveolar and vascular development and long-term respiratory morbidity, for which only supportive therapies exist. Umbilical cord-derived mesenchymal stromal cells (UC-MSCs) improve lung structure and function in experimental BPD. Results of clinical trials with MSCs for many disorders do not yet match the promising preclinical studies. A lack of specific criteria to define functionally distinct MSCs persists. Objectives: To determine and correlate single-cell UC-MSC transcriptomic profiles with therapeutic potential. Methods: UC-MSCs from five term donors and human neonatal dermal fibroblasts (HNDFs; control cells of mesenchymal origin) transcriptomes were investigated using single-cell RNA sequencing (scRNA-seq) analysis. The lung-protective effect of UC-MSCs with a distinct transcriptome and control HNDFs was tested in vivo in hyperoxia-induced neonatal lung injury in rats. Measurements and Main Results: UC-MSCs showed limited transcriptomic heterogeneity but were different from HNDFs. Gene Ontology enrichment analysis revealed distinct (progenitor-like and fibroblast-like) UC-MSC subpopulations. Only treatment with progenitor-like UC-MSCs improved lung function and structure and attenuated pulmonary hypertension in hyperoxia-exposed rat pups. Moreover, scRNA-seq identified major histocompatibility complex class I as a molecular marker of nontherapeutic cells and associated with decreased lung retention. Conclusions: UC-MSCs with a progenitor-like transcriptome, but not with a fibroblast-like transcriptome, provide lung protection in experimental BPD. High expression of major histocompatibility complex class I is associated with reduced therapeutic benefit. scRNA-seq may be useful to identify subsets of MSCs with superior repair capacity for clinical application.

Subconjunctival autologous muscle-derived mesenchymal stem cell therapy: A novel, minimally invasive approach for treating equine immune-mediated keratitis

OBJECTIVE

To establish the safety of subconjunctival injections of autologous muscle-derived mesenchymal stem cells (mdMSCs) in healthy horses and to evaluate their effect in four horses (six eyes) with severe chronic equine immune-mediated keratitis (IMMK) that was unresponsive to medical treatments.

METHODS

MdMSCs were cultured from minimally invasive muscle biopsies. In the safety group, four healthy horses received two subconjunctival injections of 2.5 and 5 million cells, respectively, at 1-month interval, to the same eye. Ocular side effects were monitored for 1 month following each injection. In the treatment group, six eyes received four to seven subconjunctival mdMSCs injections (2.5 or 5 million cells per injection) every 4 weeks, approximatively. Medical treatment was discontinued 1 week before and throughout the entire treatment period. A scoring system was used to assess the evolution of the ocular lesions.

RESULTS

In the safety group, all horses exhibited mild to moderate chemosis and conjunctival hyperemia at the injection site, lasting 24-48 h. In the treatment group, all eyes initially responded positively to therapy, with a reduction in lesion scores observed after the first injection. Four eyes achieved control of the lesions with repeated injections during the 9.2 months of follow-up.

CONCLUSION

The first subconjunctival injection of mdMSCs resulted in improvement of the ocular lesions. Repeated injections were found to be safe, minimally invasive and showed promise in managing refractory cases of equine IMMK. Further studies are warranted to demonstrate the long-term benefits of these injections and to optimize the therapeutic protocol.

Conditioned Medium of Infrapatellar Fat Stem Cells Alleviates Degradation of Chondrocyte Extracellular Matrix and Delays Development of Osteoarthritis

INTRODUCTION

Osteoarthritis (OA) is a prevalent clinical chronic degenerative condition characterized by the degeneration of articular cartilage. Currently, drug treatments for OA come with varying degrees of side effects, making the development of new therapeutic approaches for OA imperative. Mesenchymal stem cells (MSCs) are known to mitigate the progression of OA primarily through paracrine effects. The conditioned medium (CM) derived from MSCs encapsulates a variety of paracrine factors secreted by these cells.

METHODS

In this study, we investigated the effect of the CM of infrapatellar fat pad-derived MSCs (IPFSCs) on OA in vitro and in vivo, as well as and the potential underlying mechanisms. We established three experimental groups: the normal group, the OA group, and the CM intervention group. In vitro experiments, we used methods such as qPCR, Western blot, immunofluorescence, and flow cytometry to detect the impact of CM on OA chondrocytes. In vivo experiments, we evaluated the changes in the knee joints of OA rats after intra-articular injection of CM treatment.

RESULTS

The results showed that injection of CM into the knee joint inhibited OA development in a rat model induced by destabilization of the medial meniscus and anterior cruciate ligament transection. The CM increased the deposition of extracellular matrix-related components (type II collagen and Proteoglycan). The activation of PI3K/AKT/NF-κB signaling pathway was induced by IL-1β in chondrocytes, which was finally inhibited by CM-IPFSCs treatment.

CONCLUSION

In summary, IPFSCs-CM may have therapeutic potential for OA.

The Impact of Umbilical Cord Mesenchymal Stem Cells on Motor Function in Children with Cerebral Palsy: Results of a Real-world, Compassionate use Study

The aim of this study was to analyze the impact of human umbilical cord-derived MSCs (hUC-MSCs) on motor function in children with cerebral palsy (CP). The study enrolled 152 children with CP who received up to two courses of five hUC-MSCs injections. Children's motor functions were assessed with the Gross Motor Function Measure (GMFM), 6-Minute Walk Test (6-MWT), Timed Up and Go test (Up&Go test), and Lovett's test, and mental abilities were assessed with the Clinical Global Impression (CGI) scale. Data collected at visit 1 (baseline) and visit 5 (after four injections) were analyzed retrospectively. After four hUC-MSCs administrations, all evaluated parameters improved. The change in GMFM score, by a median of 1.9 points (IQR: 0.0-8.0), correlated with age. This change was observed in all GFMCS groups and was noticed in all assessed GMFM areas. A median increase of 75 m (IQR: 20.0-115.0) was noted on the 6-MWT, and this correlated with GMFM score change. Time on the Up&Go test was reduced by a median of 2 s (IQR: -3 to - 1) and the change correlated with age, GMFM score at baseline, and the difference observed on the 6-MWT. Results of Lovett's test indicated slight changes in muscle strength. According to the CGI, 75.5% (96/151) of children were seriously (level VI) or significantly ill (level V) at the 1st visit, with any improvement observed in 63.6% (96/151) of patients at the 5th visit, 23.8% (36/151) with improvement (level II) or great improvement (level I). In conclusion, the application of hUC-MSCs generally enhanced functional performance, but individual responses varied. The therapy also benefited children with high level of disability but not to the same extent as the initially less disabled children. Although younger patients responded better to the treatment, older children can also benefit. Trial Registration 152/2018/KB/VII and 119/2021/KB/VIII. Retrospective registration in ClinicalTrials: ongoing.

Bone marrow aspirate and bone marrow aspirate concentrate: Does the literature support use in long-bone nonunion and provide new insights into mechanism of action?

PURPOSE

To assess the use of bone marrow aspirate (BM) and bone marrow aspirate concentrate (BMAC) in the treatment of long-bone nonunion and to understand mechanism of action.

METHODS

A systematic review of PubMed and EBSCOHost was completed to identify studies that investigated the use of BM or BMAC for the diagnosis of delayed union and/or nonunion of long-bone fractures. Studies of isolated bone marrow-mesenchymal stem cells (BM-MSCs) and use in non-long-bone fractures were excluded. Statistical analysis was confounded by heterogeneous fracture fixation methods, treatment history, and scaffold use.

RESULTS

Our initial search yielded 430 publications, which was screened down to 25 studies. Successful treatment in aseptic nonunion was reported at 79-100% (BM) and 50-100% (BMAC). Septic nonunion rates were slightly better at 73-100% (BM) and 83.3-100% (BMAC). 18/24 studies report union rates > 80%. One study reports successful treatment of septic nonunion with BMAC and no antibiotics. A separate study reported a significant reduction in autograft reinfection rate when combined with BMAC (P = 0.009). Major adverse events include two deep infections at injection site and one case of heterotopic ossification. Most studies note transient mild donor site discomfort and potential injection site discomfort attributed to needle size.

CONCLUSION

The current literature pertaining to use of BM/BMAC for nonunion is extremely heterogeneous in terms of patient population and concomitant treatment modalities. While results are promising for use of BM/BMAC with other gold standard treatment methodologies, the literature requires additional Level I data to clarify the impact of role BM/BMAC in treating nonunion when used alone and in combination with other modalities.

LEVEL OF EVIDENCE

Level III.

Bone regeneration driven by a nano-hydroxyapatite/chitosan composite bioaerogel for periodontal regeneration

The most recent progress in reconstructive therapy for the management of periodontitis and peri-implantitis bone defects has relied on the development of highly porous biodegradable bioaerogels for guided bone regeneration. The objective of this work was to evaluate in vitro the osteoinduction of periodontal-originating cells (human dental follicle mesenchymal cells, DFMSCs) promoted by a nano-hydroxyapatite/chitosan (nHAp/CS) bioaerogel, which was purified and sterilized by a sustainable technique (supercritical CO2). Moreover, the in vivo bone regeneration capacity of the nHAp/CS bioaerogel was preliminarily assessed as a proof-of-concept on a rat calvaria bone defect model. The quantification of DNA content of DFMSCs seeded upon nHAp/CS and CS scaffolds (control material) showed a significant increase from the 14th to the 21st day of culture. These results were corroborated through confocal laser scanning microscopy analysis (CLSM). Furthermore, the alkaline phosphatase (ALP) activity increased significantly on the 21st day, similarly for both materials. Moreover, the presence of nHAp promoted a significantly higher expression of osteogenic genes after 21 days when compared to CS scaffolds and control. CLSM images of 21 days of culture also showed an increased deposition of OPN over the nHAp/CS surface. The in vivo bone formation was assessed by microCT and histological analysis. The in vivo evaluation showed a significant increase in bone volume in the nHAp/CS test group when compared to CS and the empty control, as well as higher new bone formation and calcium deposition within the nHAp/CS structure. Overall, the present study showed that the nHAp/CS bioaerogel could offer a potential solution for periodontal and peri-implant bone regeneration treatments since the in vitro results demonstrated that it provided favorable conditions for DFMSC proliferation and osteogenic differentiation, while the in vivo outcomes confirmed that it promoted higher bone ingrowth.

Clinical and preclinical studies of mesenchymal stem cells to alleviate peritoneal fibrosis

Peritoneal dialysis is an important part of end-stage kidney disease replacement therapy. However, prolonged peritoneal dialysis can result in peritoneal fibrosis and ultrafiltration failure, forcing patients to withdraw from peritoneal dialysis treatment. Therefore, there is an urgent need for some effective measures to alleviate the occurrence and progression of peritoneal fibrosis. Mesenchymal stem cells play a crucial role in immunomodulation and antifibrosis. Numerous studies have investigated the fact that mesenchymal stem cells can ameliorate peritoneal fibrosis mainly through the paracrine pathway. It has been discovered that mesenchymal stem cells participate in the improvement of peritoneal fibrosis involving the following signaling pathways: TGF-β/Smad signaling pathway, AKT/FOXO signaling pathway, Wnt/β-catenin signaling pathway, TLR/NF-κB signaling pathway. Additionally, in vitro experiments, mesenchymal stem cells have been shown to decrease mesothelial cell death and promote proliferation. In animal models, mesenchymal stem cells can enhance peritoneal function by reducing inflammation, neovascularization, and peritoneal thickness. Mesenchymal stem cell therapy has been demonstrated in clinical trials to improve peritoneal function and reduce peritoneal fibrosis, thus improving the life quality of peritoneal dialysis patients.

Mesenchymal stem cells as a promising therapy for alcohol use disorder

Alcohol Use Disorder (AUD) is a highly prevalent medical condition characterized by impaired control over alcohol consumption, despite negative consequences on the individual's daily life and health. There is increasing evidence suggesting that chronic alcohol intake, like other addictive drugs, induces neuroinflammation and oxidative stress, disrupting glutamate homeostasis in the main brain areas related to drug addiction. This review explores the potential application of mesenchymal stem cells (MSCs)-based therapy for the treatment of AUD. MSCs secrete a broad array of anti-inflammatory and antioxidant molecules, thus, the administration of MSCs, or their secretome, could reduce neuroinflammation and oxidative stress in the brain. These effects correlate with an increase in the expression of the main glutamate transporter, GLT1, which, through the normalization of the extracellular glutamate levels, could mediate the inhibitory effect of MSCs' secretome on chronic alcohol consumption, thus highlighting GLT1 as a central target to reduce chronic alcohol consumption.

Comparative single-cell transcriptional and proteomic atlas of clinical-grade injectable mesenchymal source tissues

Bone marrow aspirate concentrate (BMAC) and adipose-derived stromal vascular fraction (ADSVF) are the most marketed stem cell therapies to treat a variety of conditions in the general population and elite athletes. Both tissues have been used interchangeably clinically even though their detailed composition, heterogeneity, and mechanisms of action have neither been rigorously inventoried nor compared. This lack of information has prevented investigations into ideal dosages and has facilitated anecdata and misinformation. Here, we analyzed single-cell transcriptomes, proteomes, and flow cytometry profiles from paired clinical-grade BMAC and ADSVF. This comparative transcriptional atlas challenges the prevalent notion that there is one therapeutic cell type present in both tissues. We also provide data of surface markers that may enable isolation and investigation of cell (sub)populations. Furthermore, the proteome atlas highlights intertissue and interpatient heterogeneity of injected proteins with potentially regenerative or immunomodulatory capacities. An interactive webtool is available online.

3D Bioprinting Strategies for Articular Cartilage Tissue Engineering

Articular cartilage is the avascular and aneural tissue which is the primary connective tissue covering the surface of articulating bone. Traumatic damage or degenerative diseases can cause articular cartilage injuries that are common in the population. As a result, the demand for new therapeutic options is continually increasing for older people and traumatic young patients. Many attempts have been made to address these clinical needs to treat articular cartilage injuries, including osteoarthritis (OA); however, regenerating highly qualified cartilage tissue remains a significant obstacle. 3D bioprinting technology combined with tissue engineering principles has been developed to create biological tissue constructs that recapitulate the anatomical, structural, and functional properties of native tissues. In addition, this cutting-edge technology can precisely place multiple cell types in a 3D tissue architecture. Thus, 3D bioprinting has rapidly become the most innovative tool for manufacturing clinically applicable bioengineered tissue constructs. This has led to increased interest in 3D bioprinting in articular cartilage tissue engineering applications. Here, we reviewed current advances in bioprinting for articular cartilage tissue engineering.

Potential Plausible Role of Stem Cell for Treating Depressive Disorder: a Retrospective Review

Depression poses a significant threat to global physical and mental health, impacting around 3.8% of the population with a rising incidence. Current treatment options primarily involve medication and psychological support, yet their effectiveness remains limited, contributing to high relapse rates. There is an urgent need for innovative and more efficacious treatment modalities. Stem cell therapy, a promising avenue in regenerative medicine for a spectrum of neurodegenerative conditions, has recently garnered attention for its potential application in depression. While much of this work remains preclinical, it has demonstrated considerable promise. Identified mechanisms underlying the antidepressant effects of stem cell therapy encompass the stimulation of neurotrophic factors, immune function modulation, and augmented monoamine levels. Nonetheless, these pathways and other undiscovered mechanisms necessitate further investigation. Depression fundamentally manifests as a neurodegenerative disorder. Given stem cell therapy's success in addressing a range of neurodegenerative pathologies, it opens the door to explore its application in depression treatment. This exploration may include repairing damaged nerves directly or indirectly and inhibiting neurotoxicity. Nevertheless, significant challenges must be overcome before stem cell therapies can be applied clinically. Successful resolution of these issues will ultimately determine the feasibility of incorporating stem cell therapies into the clinical landscape. This narrative review provides insights into the progress of research, potential avenues for exploration, and the prevailing challenges in the implementation of stem cell therapy for treatment of depression.

Navigating the tumor microenvironment: mesenchymal stem cell-mediated delivery of anticancer agents

Scientific knowledge of cancer has advanced greatly throughout the years, with most recent studies findings includes many hallmarks that capture disease's multifaceted character. One of the novel approach utilised for the delivery of anti-cancer agents includes mesenchymal stem cell mediated drug delivery. Mesenchymal stem cells (MSCs) are non-haematopoietic progenitor cells that may be extracted from bone marrow, tooth pulp, adipose tissue and placenta/umbilical cord blood dealing with adult stem cells. MSCs are mostly involved in regeneration of tissue, they have also been shown to preferentially migrate to location of several types of tumour in-vivo. Usage of MSCs ought to improve both effectiveness and safety of anti-cancer drugs by enhancing delivery efficiency of anti-cancer therapies to tumour site. Numerous researches has demonstrated that various drugs, when delivered via mesenchymal stem cell mediated delivery can elicit anti-tumour effect of cells in cancers of breast cells and thyroid cells. MSCs have minimal immunogenicity because to lack of co-stimulatory molecule expression, which means there is no requirement for immunosuppression after allogenic transplantation. This current review elaborates recent advancements of mesenchyma stem cell mediated drug delivery of anti-cancer agents along with its mechanism and previously reported studies of drugs manufactured via this drug delivery system.

Inflammatory and bone remodelling related biomarkers following periodontal transplantation of the tissue engineered biocomplex

OBJECTIVES

To assess gingival crevicular fluid (GCF) levels of inflammatory and bone remodelling related biomarkers following transplantation of a tissue-engineered biocomplex into intrabony defects at several time-points over 12-months.

MATERIALS AND METHODS

Group-A (n = 9) received the Minimal Access Flap (MAF) surgical technique combined with a biocomplex of autologous clinical-grade alveolar bone-marrow mesenchymal stem cells in collagen scaffolds enriched with an autologous fibrin/platelet lysate (aFPL). Group-B (n = 10) received the MAF surgery, with collagen scaffolds enriched with aFPL and Group-C (n = 8) received the MAF surgery alone. GCF was collected from the osseous defects of subjects via paper strips/30 sec at baseline, 6-weeks, 3-, 6-, 9-, 12-months post-surgery. Levels of inflammatory and bone remodelling-related biomarkers in GCF were determined by ELISA.

RESULTS

Group-A demonstrated significantly higher GCF levels of BMP-7 at 6-9 months than baseline, with gradually decreasing levels of pro-inflammatory and pro-osteoclastogenic markers (TNF-α, RANKL) over the study-period; and an overall decrease in the RANKL/OPG ratio at 9-12 months than baseline (all p < 0.001). In comparison, only modest interim changes were observed in Groups-B and -C.

CONCLUSIONS

At the protein level, the approach of MAF and biocomplex transplantation provided greater tissue regeneration potential as cell-based therapy appeared to modulate inflammation and bone remodelling in residual periodontal defects.

CLINICAL RELEVANCE

Transplantation of a tissue engineered construct into periodontal intrabony defects demonstrated a biochemical pattern for inflammatory control and tissue regeneration over 12-months compared to the control treatments. Understanding the biological healing events of stem cell transplantation may facilitate the design of novel treatment strategies.

CLINICAL DATABASE REGISTRATION

ClinicalTrials.gov ID: NCT02449005.

Preclinical and Clinical Studies on the Use of Extracellular Vesicles Derived from Mesenchymal Stem Cells in the Treatment of Chronic Wounds

To date, the widespread implementation of therapeutic strategies for the treatment of chronic wounds, including debridement, infection control, and the use of grafts and various dressings, has been time-consuming and accompanied by many challenges, with definite success not yet achieved. Extensive studies on mesenchymal stem cells (MSCs) have led to suggestions for their use in treating various diseases. Given the existing barriers to utilizing such cells and numerous pieces of evidence indicating the crucial role of the paracrine signaling system in treatments involving MSCs, extracellular vesicles (EVs) derived from these cells have garnered significant attention in treating chronic wounds in recent years. This review begins with a general overview of current methods for chronic wound treatment, followed by an exploration of EV structure, biogenesis, extraction methods, and characterization. Subsequently, utilizing databases such as Google Scholar, PubMed, and ScienceDirect, we have explored the latest findings regarding the role of EVs in the healing of chronic wounds, particularly diabetic and burn wounds. In this context, the role and mode of action of these nanoparticles in healing chronic wounds through mechanisms such as oxygen level elevation, oxidative stress damage reduction, angiogenesis promotion, macrophage polarization assistance, etc., as well as the use of EVs as carriers for engineered nucleic acids, have been investigated. The upcoming challenges in translating EV-based treatments for healing chronic wounds, along with possible approaches to address these challenges, are discussed. Additionally, clinical trial studies in this field are also covered.

Activating the healing process: three-dimensional culture of stem cells in Matrigel for tissue repair

BACKGROUND

To establish a strategy for stem cell-related tissue regeneration therapy, human gingival mesenchymal stem cells (hGMSCs) were loaded with three-dimensional (3D) bioengineered Matrigel matrix scaffolds in high-cell density microtissues to promote local tissue restoration.

METHODS

The biological performance and stemness of hGMSCs under 3D culture conditions were investigated by viability and multidirectional differentiation analyses. A Sprague‒Dawley (SD) rat full-thickness buccal mucosa wound model was established, and hGMSCs/Matrigel were injected into the submucosa of the wound. Autologous stem cell proliferation and wound repair in local tissue were assessed by histomorphometry and immunohistochemical staining.

RESULTS

Three-dimensional suspension culture can provide a more natural environment for extensions and contacts between hGMSCs, and the viability and adipogenic differentiation capacity of hGMSCs were significantly enhanced. An animal study showed that hGMSCs/Matrigel significantly accelerated soft tissue repair by promoting autologous stem cell proliferation and enhancing the generation of collagen fibers in local tissue.

CONCLUSION

Three-dimensional cell culture with hydrogel scaffolds, such as Matrigel, can effectively improve the biological function and maintain the stemness of stem cells. The therapeutic efficacy of hGMSCs/Matrigel was confirmed, as these cells could effectively stimulate soft tissue repair to promote the healing process by activating the host microenvironment and autologous stem cells.

Optimization of the Parameters Influencing the Antioxidant Activity and Concentration of Carotenoids Extracted from Pumpkin Peel Using a Central Composite Design

It has been discovered that the peel of a pumpkin (Cucurbita maxima), regarded as a waste product of pumpkin processing, has significant amounts of carotenoids and other antioxidants. This study aims to identify the most effective extraction parameters for an ultrasonic-assisted extraction method to extract the total carotenoids (TCs) and assess the antioxidant activity (AA) of pumpkin peel. To determine the effects of the extraction time, temperature, and material-to-solvent ratio on the recovery of TCs and AA, a response surface methodology utilizing the central composite design (CCD) was used. The extraction temperature (6.25-98.75 °C), extraction duration (13.98-128.98 min), and solvent ratio (0.23-50.23 mL) were the variables studied in the coded form of the experimental plan. The carotenoid concentration varied from 0.53 to 1.06 mg/g DW, while the AA varied from 0.34 to 7.28 µM TE/g DW. The findings indicated that the optimal extraction parameters were an 80 °C temperature, a 10 mL solvent ratio, and a 100 min extraction time. The study confirmed that the optimum extraction conditions resulted in an experimental TC yield of 0.97 mg/g DW and an AA of 7.25 µM TE/g DW. Overall, it should be emphasized that the extraction process can be enhanced by setting the operating factors to maximize the model responses.

Modulation of Canine Adipose-Derived Mesenchymal Stem/Medicinal Signalling Cells with Ascorbic Acid: Effect on Proliferation and Chondrogenic Differentiation on Standard Plastic and Silk Fibroin Surfaces

Ascorbic acid (AA) plays a crucial role in both the proliferation and chondrogenic differentiation potential of mesenchymal stem/medicinal signalling cells (MSCs); these are both key aspects of their general therapeutic use and their increasing use in veterinary medicine. Current immunomodulatory therapies require efficient expansion of MSCs in the laboratory, while emerging tissue regeneration strategies, such as cartilage or bone repair, aim to use differentiated MSCs and modulate the expression of chondrogenic and hypertrophic markers. Our aim was to investigate whether the addition of AA to the growth medium enhances the proliferation of canine adipose-derived MSCs (cAMSCs) grown on standard plastic surfaces and whether it affects chondrogenic differentiation potential on silk fibroin (SF) films. We assessed cell viability with trypan blue and proliferation potential by calculating population doubling. Chondrogenic induction on SF films was assessed by Alcian blue staining and gene expression analysis of chondrogenic and hypertrophic genes. The results showed that growth medium with AA significantly enhanced the proliferation of cAMSCs without affecting cell viability and modulated the expression of chondrogenic and hypertrophic genes of cAMSCs grown on SF films. Our results suggest that AA may be used in growth medium for expansion of cAMSCs and, at the same time, provide the basis for future studies to investigate the role of AA and SF in chondrogenic differentiation of MSCs.

Mesenchymal stem cells in animal reproduction: sources, uses and scenario

Studies regarding mesenchymal stem cells turned up in the 1960's and this cell type created a great number of questions about its functions and applicability in science and medicine. When used with therapeutic intent, these cells present an inclination to migrate to sites of injury, inflammation or disease, where they secrete bioactive factors that stimulates the synthesis of new tissue. In this context, studies using rodents reported that MSCs promoted positive effects in the ovarian function in mice with premature aging of follicular reserve. In female bovines, experimental stem cell-based therapies have been used to either generate new oocytes with in vitro quality or stimulate such action in vivo. It is also reported, that the intraovarian application of mesenchymal stem cells generates a greater production of embryos in vitro and the production of early and expanded blastocysts. Additionally, analysis of ovarian tissue in animal subjected to treatment showed an increase in the number of developing follicles. Nevertheless, the treatments involving stem cells with different modes of application, different sources and different species were able to act on the hormonal, tissue, cellular and metabolic levels, generating positive results in the recovery and improvement of ovarian functions.

Transitioning from static to suspension culture system for large-scale production of xeno-free extracellular vesicles derived from mesenchymal stromal cells

Extracellular vesicles (EVs) derived from mesenchymal stromal cells (MSCs) have shown increasing therapeutic potential in the last years. However, large production of EV is required for therapeutic purposes. Thereby, scaling up MSC cultivation in bioreactors is essential to allow culture parameters monitoring. In this study, we reported the establishment of a scalable bioprocess to produce MSC-EV in suspension cultures using spinner flasks and human collagen-coated microcarriers (3D culture system). We compared the EV production in this 3D culture system with the standard static culture using T-flasks (2D culture system). The EV produced in both systems were characterized and quantify by western blotting and nanoparticle tracking analysis. The presence of the typical protein markers CD9, CD63, and CD81 was confirmed by western blotting analyses for EV produced in both culture systems. The cell fold-increase was 5.7-fold for the 3D culture system and 4.6-fold for the 2D culture system, signifying a fold-change of 1.2 (calculated as the ratio of fold-increase 3D to fold-increase 2D). Furthermore, it should be noted that the total cell production in the spinner flask cultures was 4.8 times higher than that in T-flask cultures. The total cell production in the spinner flask cultures was 5.2-fold higher than that in T-flask cultures. While the EV specific production (particles/cell) in T-flask cultures (4.40 ± 1.21 × 108 particles/mL, p < 0.05) was higher compared to spinner flask cultures (2.10 ± 0.04 × 108 particles/mL, p < 0.05), the spinner flask culture system offers scalability, making it capable of producing enough MSC-EV at a large scale for clinical applications. Therefore, we concluded that 3D culture system evaluated here serves as an efficient transitional platform that enables the scaling up of MSC-EV production for therapeutic purposes by utilizing stirred tank bioreactors and maintaining xeno-free conditions.

Exosome-loaded decellularized tissue: Opening a new window for regenerative medicine

Mesenchymal stem cell-derived exosomes (MSCs-EXO) have received a lot of interest recently as a potential therapeutic tool in regenerative medicine. Extracellular vesicles (EVs) known as exosomes (EXOs) are crucial for cell-cell communication throughout a variety of activities including stress response, aging, angiogenesis, and cell differentiation. Exploration of the potential use of EXOs as essential therapeutic effectors of MSCs to encourage tissue regeneration was motivated by success in the field of regenerative medicine. EXOs have been administered to target tissues using a variety of methods, including direct, intravenous, intraperitoneal injection, oral delivery, and hydrogel-based encapsulation, in various disease models. Despite the significant advances in EXO therapy, various methods are still being researched to optimize the therapeutic applications of these nanoparticles, and it is not completely clear which approach to EXO administration will have the greatest effects. Here, we will review emerging developments in the applications of EXOs loaded into decellularized tissues as therapeutic agents for use in regenerative medicine in various tissues.