Concise Review: Mesenchymal Stem Cell-Based Drug Delivery: The Good, the Bad, the Ugly, and the Promise

Cutting-edge regenerative therapy for Hirschsprung disease and its allied disorders

Hirschsprung disease (HSCR) and its associated disorders (AD-HSCR) often result in severe hypoperistalsis caused by enteric neuropathy, mesenchymopathy, and myopathy. Notably, HSCR involving the small intestine, isolated hypoganglionosis, chronic idiopathic intestinal pseudo-obstruction, and megacystis-microcolon-intestinal hypoperistalsis syndrome carry a poor prognosis. Ultimately, small-bowel transplantation (SBTx) is necessary for refractory cases, but it is highly invasive and outcomes are less than optimal, despite advances in surgical techniques and management. Thus, regenerative therapy has come to light as a potential form of treatment involving regeneration of the enteric nervous system, mesenchyme, and smooth muscle in affected areas. We review the cutting-edge regenerative therapeutic approaches for managing HSCR and AD-HSCR, including the use of enteric nervous system progenitor cells, embryonic stem cells, induced pluripotent stem cells, and mesenchymal stem cells as cell sources, the recipient intestine's microenvironment, and transplantation methods. Perspectives on the future of these treatments are also discussed.

Syngeneic mesenchymal stem cells loaded with telomerase-dependent oncolytic adenoviruses enhance anti-metastatic efficacy

Oncolytic adenoviruses have emerged as a promising therapeutic approach for cancer therapy. However, systemic delivery of the viruses to metastatic tumors remains a major challenge. Mesenchymal stem cells (MSCs) possess tumor tropism property and can be used as cellular vehicles for delivering oncolytic adenoviruses to tumor sites. Since telomerase activity is found in ~90% of human carcinomas, but undetected in normal adult cells, the human telomerase reverse transcriptase gene (TERT) promoter can be exploited for regulating the replication of oncolytic adenoviruses. Here, we evaluated the antitumor effects of syngeneic murine MSCs loaded with the luciferase-expressing, telomerase-dependent oncolytic adenovirus Ad.GS2 (MSC-Ad.GS2) and Ad.GS2 alone on metastatic MBT-2 bladder tumors. MSCs supported a low degree of Ad.GS2 replication, which could be augmented by coculture with MBT-2 cells or tumor-conditioned medium (TCM), suggesting that viral replication is increased when MSC-Ad.GS2 migrates to tumor sites. MBT-2 cells and TCM enhanced viral replication in Ad.GS2-infected MSCs. SDF-1 is a stem cell homing factor. Our results suggest that the SDF-1/STAT3/TERT signaling axis in MSCs in response to the tumor microenvironment may contribute to the enhanced replication of Ad.GS2 carried by MSCs. Notably, we demonstrate the potent therapeutic efficacy of systemically delivered MSC-Ad.GS2 in pleural disseminated tumor and experimental metastasis models using intrapleural and tail vein injection of MBT-2 cells, respectively. Treatment with MSC-Ad.GS2 significantly reduced tumor growth and prolonged the survival of mice bearing metastatic bladder tumors. Since telomerase is expressed in a broad spectrum of cancers, this therapeutic strategy may be broadly applicable.

Vascular endothelial growth factor secretion and immunosuppression are distinct potency mechanisms of human bone marrow mesenchymal stromal cells

Mesenchymal stromal cells (MSCs) are investigated as cellular therapeutics for inflammatory bowel diseases and associated perianal fistula, although consistent efficacy remains a concern. Determining host factors that modulate MSCs' potency including their secretion of angiogenic and wound-healing factors, immunosuppression, and anti-inflammatory properties are important determinants of their functionality. We investigated the mechanisms that regulate the secretion of angiogenic and wound-healing factors and immune suppression of human bone marrow MSCs. Secretory analysis of MSCs focusing on 18 angiogenic and wound-healing secretory molecules identified the most abundancy of vascular endothelial growth factor A (VEGF-A). MSC viability and secretion of other angiogenic factors are not dependent on VEGF-A secretion which exclude the autocrine role of VEGF-A on MSC's fitness. However, the combination of inflammatory cytokines IFNγ and TNFα reduces MSC's VEGF-A secretion. To identify the effect of intestinal microvasculature on MSCs' potency, coculture analysis was performed between human large intestine microvascular endothelial cells (HLMVECs) and human bone marrow-derived MSCs. HLMVECs do not attenuate MSCs' viability despite blocking their VEGF-A secretion. In addition, HLMVECs neither attenuate MSC's IFNγ mediated upregulation of immunosuppressive enzyme indoleamine 2,3-dioxygenase nor abrogate suppression of T-cell proliferation despite the attenuation of VEGF-A secretion. We found that HLMVECs express copious amounts of endothelial nitric oxide synthase and mechanistic analysis showed that pharmacological blocking reverses HLMVEC-mediated attenuation of MSC's VEGF-A secretion. Together these results suggest that secretion of VEGF-A and immunosuppression are separable functions of MSCs which are regulated by distinct mechanisms in the host.

Nanotechnology and bioengineering approaches to improve the potency of mesenchymal stem cell as an off-the-shelf versatile tumor delivery vehicle

Targeting actionable mutations in oncogene-driven cancers and the evolution of immuno-oncology are the two prominent revolutions that have influenced cancer treatment paradigms and caused the emergence of precision oncology. However, intertumoral and intratumoral heterogeneity are the main challenges in both fields of precision cancer treatment. In other words, finding a universal marker or pathway in patients suffering from a particular type of cancer is challenging. Therefore, targeting a single hallmark or pathway with a single targeted therapeutic will not be efficient for fighting against tumor heterogeneity. Mesenchymal stem cells (MSCs) possess favorable characteristics for cellular therapy, including their hypoimmune nature, inherent tumor-tropism property, straightforward isolation, and multilineage differentiation potential. MSCs can be loaded with various chemotherapeutics and oncolytic viruses. The combination of these intrinsic features with the possibility of genetic manipulation makes them a versatile tumor delivery vehicle that can be used for in vivo selective tumor delivery of various chemotherapeutic and biological therapeutics. MSCs can be used as biofactory for the local production of chemical or biological anticancer agents at the tumor site. MSC-mediated immunotherapy could facilitate the sustained release of immunotherapeutic agents specifically at the tumor site, and allow for the achievement of therapeutic concentrations without the need for repetitive systemic administration of high therapeutic doses. Despite the enthusiasm evoked by preclinical studies that used MSC in various cancer therapy approaches, the translation of MSCs into clinical applications has faced serious challenges. This manuscript, with a critical viewpoint, reviewed the preclinical and clinical studies that have evaluated MSCs as a selective tumor delivery tool in various cancer therapy approaches, including gene therapy, immunotherapy, and chemotherapy. Then, the novel nanotechnology and bioengineering approaches that can improve the potency of MSC for tumor targeting and overcoming challenges related to their low localization at the tumor sites are discussed.

Precision Nanomedicine with Bio-Inspired Nanosystems: Recent Trends and Challenges in Mesenchymal Stem Cells Membrane-Coated Bioengineered Nanocarriers in Targeted Nanotherapeutics

In the recent past, the formulation and development of nanocarriers has been elaborated into the broader fields and opened various avenues in their preclinical and clinical applications. In particular, the cellular membrane-based nanoformulations have been formulated to surpass and surmount the limitations and restrictions associated with naïve or free forms of therapeutic compounds and circumvent various physicochemical and immunological barriers including but not limited to systemic barriers, microenvironmental roadblocks, and other cellular or subcellular hinderances-which are quite heterogeneous throughout the diseases and patient cohorts. These limitations in drug delivery have been overcome through mesenchymal cells membrane-based precision therapeutics, where these interventions have led to the significant enhancements in therapeutic efficacies. However, the formulation and development of nanocarriers still focuses on optimization of drug delivery paradigms with a one-size-fits-all resolutions. As mesenchymal stem cell membrane-based nanocarriers have been engineered in highly diversified fashions, these are being optimized for delivering the drug payloads in more and better personalized modes, entering the arena of precision as well as personalized nanomedicine. In this Review, we have included some of the advanced nanocarriers which have been designed and been utilized in both the non-personalized as well as precision applicability which can be employed for the improvements in precision nanotherapeutics. In the present report, authors have focused on various other aspects of the advancements in stem cells membrane-based nanoparticle conceptions which can surmount several roadblocks and barriers in drug delivery and nanomedicine. It has been suggested that well-informed designing of these nanocarriers will lead to appreciable improvements in the therapeutic efficacy in therapeutic payload delivery applications. These approaches will also enable the tailored and customized designs of MSC-based nanocarriers for personalized therapeutic applications, and finally amending the patient outcomes.

Efficacy and safety of mesenchymal stem cells therapy in COVID-19 patients: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

The coronavirus disease 2019 (COVID-19) has become a serious public health issue. In COVID-19 patients, the elevated levels of inflammatory cytokines lead to the manifestation of COVID-19 symptoms, such as lung tissue edema, lung diffusion dysfunction, acute respiratory distress syndrome (ARDS), secondary infection, and ultimately mortality. Mesenchymal stem cells (MSCs) exhibit anti-inflammatory and immunomodulatory properties, thus providing a potential treatment option for COVID-19. The number of clinical trials of MSCs for COVID-19 has been rising. However, the treatment protocols and therapeutic effects of MSCs for COVID-19 patients are inconsistent. This meta-analysis was performed to systematically determine the safety and efficacy of MSC infusion in COVID-19 patients.

METHODS

We conducted a comprehensive literature search from PubMed/Medline, Web of Science, EMBASE, and Cochrane Library up to 22 November 2023 to screen for eligible randomized controlled trials. Inclusion and exclusion criteria for searched literature were formulated according to the PICOS principle, followed by the use of literature quality assessment tools to assess the risk of bias. Finally, outcome measurements including therapeutic efficacy, clinical symptoms, and adverse events of each study were extracted for statistical analysis.

RESULTS

A total of 14 randomized controlled trials were collected. The results of enrolled studies demonstrated that patients with COVID-19 pneumonia who received MSC inoculation showed a decreased mortality compared with counterparts who received conventional treatment (RR: 0.76; 95% CI [0.60, 0.96]; p = 0.02). Reciprocally, MSC inoculation improved the clinical symptoms in patients (RR: 1.28; 95% CI [1.06, 1.55]; p = 0.009). In terms of immune biomarkers, MSC treatment inhibited inflammation responses in COVID-19 patients, as was indicated by the decreased levels of CRP and IL-6. Importantly, our results showed that no significant differences in the incidence of adverse reactions or serious adverse events were monitored in patients after MSC inoculation.

CONCLUSION

This meta-analysis demonstrated that MSC inoculation is effective and safe in the treatment of patients with COVID-19 pneumonia. Without increasing the incidence of adverse events or serious adverse events, MSC treatment decreased patient mortality and inflammatory levels and improved the clinical symptoms in COVID-19 patients. However, large-cohort randomized controlled trials with expanded numbers of patients are required to further confirm our results.

A novel cell-free therapy using exosomes in the inner ear regeneration

Cellular and molecular alterations associated with hearing loss are now better understood with advances in molecular biology. These changes indicate the participation of distinct damage and stress pathways that are unlikely to be fully addressed by conventional pharmaceutical treatment. Sensorineural hearing loss is a common and debilitating condition for which comprehensive pharmacologic intervention is not available. The complex and diverse molecular pathology that underlies hearing loss currently limits our ability to intervene with small molecules. The present review focuses on the potential for the use of extracellular vesicles in otology. It examines a variety of inner ear diseases and hearing loss that may be treatable using exosomes (EXOs). The role of EXOs as carriers for the treatment of diseases related to the inner ear as well as EXOs as biomarkers for the recognition of diseases related to the ear is discussed.

The Main Mechanisms of Mesenchymal Stem Cell-Based Treatments against COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19) has a clinical manifestation of hypoxic respiratory failure and acute respiratory distress syndrome. However, COVID-19 still lacks of effective clinical treatments so far. As a promising potential treatment against COVID-19, stem cell therapy raised recently and had attracted much attention. Here we review the mechanisms of mesenchymal stem cell-based treatments against COVID-19, and provide potential cues for the effective control of COVID-19 in the future.

METHODS

Literature is obtained from databases PubMed and Web of Science. Key words were chosen for COVID- 19, acute respiratory syndrome coronavirus 2, mesenchymal stem cells, stem cell therapy, and therapeutic mechanism. Then we summarize and critically analyze the relevant articles retrieved.

RESULTS

Mesenchymal stem cell therapy is a potential effective treatment against COVID-19. Its therapeutic efficacy is mainly reflected in reducing severe pulmonary inflammation, reducing lung injury, improving pulmonary function, protecting and repairing lung tissue of the patients. Possible therapeutic mechanisms might include immunoregulation, anti-inflammatory effect, tissue regeneration, anti-apoptosis effect, antiviral, and antibacterial effect, MSC - EVs, and so on.

CONCLUSION

Mesenchymal stem cells can effectively treat COVID-19 through immunoregulation, anti-inflammatory, tissue regeneration, anti-apoptosis, anti-virus and antibacterial, MSC - EVs, and other ways. Systematically elucidating the mechanisms of mesenchymal stem cell-based treatments for COVID-19 will provide novel insights into the follow-up research and development of new therapeutic strategies in next step.

Current Strategies and Therapeutic Applications of Mesenchymal Stem Cell-Based Drug Delivery

Mesenchymal stem cells (MSCs) have emerged as a promising approach for drug delivery strategies because of their unique properties. These strategies include stem cell membrane-coated nanoparticles, stem cell-derived extracellular vesicles, immunomodulatory effects, stem cell-laden scaffolds, and scaffold-free stem cell sheets. MSCs offer advantages such as low immunogenicity, homing ability, and tumor tropism, making them ideal for targeted drug delivery systems. Stem cell-derived extracellular vesicles have gained attention for their immune properties and tumor-homing abilities, presenting a potential solution for drug delivery challenges. The relationship between MSC-based drug delivery and the self-renewal and differentiation capabilities of MSCs lies in the potential of engineered MSCs to serve as effective carriers for therapeutic agents while maintaining their intrinsic properties. MSCs exhibit potent immunosuppressive functions in MSC-based drug delivery strategies. Stem cell-derived EVs have low immunogenicity and strong therapeutic potential for tissue repair and regeneration. Scaffold-free stem cell sheets represent a cutting-edge approach in regenerative medicine, offering a versatile platform for tissue engineering and regeneration across different medical specialties. MSCs have shown great potential for clinical applications in regenerative medicine because of their ability to differentiate into various cell types, secrete bioactive factors, and modulate immune responses. Researchers are exploring these innovative approaches to enhance drug delivery efficiency and effectiveness in treating various diseases.

Mesenchymal Stromal Cells: New Generation Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract, which has a high recurrence rate and is incurable due to a lack of effective treatment. Mesenchymal stromal cells (MSCs) are a class of pluripotent stem cells that have recently received a lot of attention due to their strong self-renewal ability and immunomodulatory effects, and a large number of experimental and clinical models have confirmed the positive therapeutic effect of MSCs on IBD. In preclinical studies, MSC treatment for IBD relies on MSCs paracrine effects, cell-to-cell contact, and its mediated mitochondrial transfer for immune regulation. It also plays a therapeutic role in restoring the intestinal mucosal barrier through the homing effect, regulation of the intestinal microbiome, and repair of intestinal epithelial cells. In the latest clinical trials, the safety and efficacy of MSCs in the treatment of IBD have been confirmed by transfusion of autologous or allogeneic bone marrow, umbilical cord, and adipose MSCs, as well as their derived extracellular vesicles. However, regarding the stable and effective clinical use of MSCs, several concerns emerge, including the cell sources, clinical management (dose, route and frequency of administration, and pretreatment of MSCs) and adverse reactions. This article comprehensively summarizes the effects and mechanisms of MSCs in the treatment of IBD and its advantages over conventional drugs, as well as the latest clinical trial progress of MSCs in the treatment of IBD. The current challenges and future directions are also discussed. This review would add knowledge into the understanding of IBD treatment by applying MSCs.

Advances in Engineered Nanoparticles for the Treatment of Ischemic Stroke by Enhancing Angiogenesis

Angiogenesis, or the formation of new blood vessels, is a natural defensive mechanism that aids in the restoration of oxygen and nutrition delivery to injured brain tissue after an ischemic stroke. Angiogenesis, by increasing vessel development, may maintain brain perfusion, enabling neuronal survival, brain plasticity, and neurologic recovery. Induction of angiogenesis and the formation of new vessels aid in neurorepair processes such as neurogenesis and synaptogenesis. Advanced nano drug delivery systems hold promise for treatment stroke by facilitating efficient transportation across the the blood-brain barrier and maintaining optimal drug concentrations. Nanoparticle has recently been shown to greatly boost angiogenesis and decrease vascular permeability, as well as improve neuroplasticity and neurological recovery after ischemic stroke. We describe current breakthroughs in the development of nanoparticle-based treatments for better angiogenesis therapy for ischemic stroke employing polymeric nanoparticles, liposomes, inorganic nanoparticles, and biomimetic nanoparticles in this study. We outline new nanoparticles in detail, review the hurdles and strategies for conveying nanoparticle to lesions, and demonstrate the most recent advances in nanoparticle in angiogenesis for stroke treatment.

Dynamic tracking of human umbilical cord mesenchymal stem cells (hUC-MSCs) following intravenous administration in mice model

Introduction

In the past decades, human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) have sparked interest in cellular therapy due to their immunomodulatory properties. Nevertheless, the fate of hUC-MSCs in the body remains poorly understood. This study aimed to investigate the biodistribution, homing and clearance of systemically administered hUC-MSCs in healthy BALB/c mice model.

Methods

hUC-MSCs were labelled with GFP-Luc2 protein, followed by characterisation with flow cytometry. Upon intravenous infusion of transduced hUC-MSCs into the healthy BALB/c mice, the cells were dynamically monitored through the bioluminescent imaging (BLI) approach.

Results

Transduction of hUC-MSCs with GFP-Luc2 not only preserved the characteristics of MSCs, but also allowed live monitoring of transduced cells in the mice model. Upon systemic administration, BLI showed that transduced hUC-MSCs first localised predominantly in the lungs of healthy BALB/c mice and mainly remained in the lungs for up to 3 days before eventually cleared from the body. At terminal sacrifice, plasma chemistry biomarkers remained unchanged except for C-peptide levels, which were significantly reduced in the hUC-MSCs group. Histopathological findings further revealed that hUC-MSCs infusion did not cause any adverse effects and toxicity to lung, liver and heart tissues.

Conclusions

Collectively, systemically administrated hUC-MSCs was safe and demonstrated dynamic homing capacity before eventually disappearing from the body.

Plasticity and crosstalk of mesenchymal stem cells and macrophages in immunomodulation in sepsis

Sepsis is a multisystem disease characterized by dysregulation of the host immune response to infection. Immune response kinetics play a crucial role in the pathogenesis and progression of sepsis. Macrophages, which are known for their heterogeneity and plasticity, actively participate in the immune response during sepsis. These cells are influenced by the ever-changing immune microenvironment and exhibit two-sided immune regulation. Recently, the immunomodulatory function of mesenchymal stem cells (MSCs) in sepsis has garnered significant attention. The immune microenvironment can profoundly impact MSCs, prompting them to exhibit dual immunomodulatory functions akin to a double-edged sword. This discovery holds great importance for understanding sepsis progression and devising effective treatment strategies. Importantly, there is a close interrelationship between macrophages and MSCs, characterized by the fact that during sepsis, these two cell types interact and cooperate to regulate inflammatory processes. This review summarizes the plasticity of macrophages and MSCs within the immune microenvironment during sepsis, as well as the intricate crosstalk between them. This remains an important concern for the future use of these cells for immunomodulatory treatments in the clinic.

Efficacy and Mechanism of a Biomimetic Nanosystem Carrying Doxorubicin and an IDO Inhibitor for Treatment of Advanced Triple-Negative Breast Cancer

Introduction

Chemotherapy is still the treatment of choice for advanced triple-negative breast cancer. Chemotherapy combined with immunotherapy is being tried in patients with triple-negative breast cancer. As a kind of "cold tumor", triple-negative breast cancer has a bottleneck in immunotherapy. Indoleamine 2, 3-dioxygenase-1 inhibitors can reverse the immunosuppressive state and enhance the immune response.

Methods

In this study, mesoporous silica nanoparticles were coated with the chemotherapeutic drug doxorubicin and indoleamine 2, 3-dioxygenase 1 inhibitor 1-Methyl-DL-tryptophan (1-MT), and then encapsulate the surfaces of a triple-negative breast cancer cell membrane to construct the tumor dual-targeted delivery system CDIMSN for chemotherapy and immunotherapy, and to investigate the immunogenic death effect of CDIMSN.

Results and discussion

The CDIMSN could target the tumor microenvironment. Doxorubicin induced tumor immunogenic death, while 1-MT reversed immunosuppression. In vivo findings showed that the tumor size in the CDIMSN group was 2.66-fold and 1.56-fold smaller than that in DOX and DIMSN groups, respectively. CDIMSN group was better than naked DIMSN in stimulating CD8+T cells, CD4+T cells and promoting Dendritic Cells(DC) maturation. In addition, blood analysis, biochemical analysis and Hematoxylin staining analysis of mice showed that the bionic nanoparticles had good biological safety.

Emerging role of mesenchymal stromal cells in gynecologic cancer therapy

Mesenchymal stromal cells (MSCs) show considerable promise in regenerative medicine with superior anti-fibrotic, immunomodulatory, and angiogenic functions. More recently, discovered with the tumor tropism, MSCs have been exploited as the basis of targeted cancer therapy. In this scenario, MSCs can directly home to tumor tissues and play anti-tumor properties. In addition, MSCs, MSC-derived exosomes and MSC-derived membranes are often developed as carriers for precisely delivering cytotoxic agents to cancer sites, including chemotherapeutic drugs, therapeutic genes, or oncolytic viruses. However, it has revealed the tumorigenic risk of MSCs as an important component within the tumor microenvironment, hampering the translation of MSC-based cancer therapies into clinical settings. Therefore, in this review, we introduce the specific tumor-tropic ability of MSCs and underlying mechanisms. We also summarize the current application of MSC-based therapeutic approaches in treating gynecologic cancers, mainly including cervical, ovarian, and endometrial cancers. Moreover, we discuss the main challenges that the current MSC-based cancer therapies are facing.

Nanoparticles and Mesenchymal Stem Cell (MSC) Therapy for Cancer Treatment: Focus on Nanocarriers and a si-RNA CXCR4 Chemokine Blocker as Strategies for Tumor Eradication In Vitro and In Vivo

Mesenchymal stem cells (MSCs) have a high tropism for the hypoxic microenvironment of tumors. The combination of nanoparticles in MSCs decreases tumor growth in vitro as well as in rodent models of cancers in vivo. Covalent conjugation of nanoparticles with the surface of MSCs can significantly increase the drug load delivery in tumor sites. Nanoparticle-based anti-angiogenic systems (gold, silica and silicates, diamond, silver, and copper) prevented tumor growth in vitro. For example, glycolic acid polyconjugates enhance nanoparticle drug delivery and have been reported in human MSCs. Labeling with fluorescent particles (coumarin-6 dye) identified tumor cells using fluorescence emission in tissues; the conjugation of different types of nanoparticles in MSCs ensured success and feasibility by tracking the migration and its intratumor detection using non-invasive imaging techniques. However, the biosafety and efficacy; long-term stability of nanoparticles, and the capacity for drug release must be improved for clinical implementation. In fact, MSCs are vehicles for drug delivery with nanoparticles and also show low toxicity but inefficient accumulation in tumor sites by clearance of reticuloendothelial organs. To solve these problems, the internalization or conjugation of drug-loaded nanoparticles should be improved in MSCs. Finally, CXCR4 may prove to be a promising target for immunotherapy and cancer treatment since the delivery of siRNA to knock down this alpha chemokine receptor or CXCR4 antagonism has been shown to disrupt tumor-stromal interactions.

Intranasal delivery of stem cells labeled by nanoparticles in neurodegenerative disorders: Challenges and opportunities

Neurodegenerative disorders occur through progressive loss of function or structure of neurons, with loss of sensation and cognition values. The lack of successful therapeutic approaches to solve neurologic disorders causes physical disability and paralysis and has a significant socioeconomic impact on patients. In recent years, nanocarriers and stem cells have attracted tremendous attention as a reliable approach to treating neurodegenerative disorders. In this regard, nanoparticle-based labeling combined with imaging technologies has enabled researchers to survey transplanted stem cells and fully understand their fate by monitoring their survival, migration, and differentiation. For the practical implementation of stem cell therapies in the clinical setting, it is necessary to accurately label and follow stem cells after administration. Several approaches to labeling and tracking stem cells using nanotechnology have been proposed as potential treatment strategies for neurological diseases. Considering the limitations of intravenous or direct stem cell administration, intranasal delivery of nanoparticle-labeled stem cells in neurological disorders is a new method of delivering stem cells to the central nervous system (CNS). This review describes the challenges and limitations of stem cell-based nanotechnology methods for labeling/tracking, intranasal delivery of cells, and cell fate regulation as theragnostic labeling. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease.

Efficacy and safety of mesenchymal stem cell therapy in liver cirrhosis: a systematic review and meta-analysis

AIM

Although the efficacy and safety of mesenchymal stem cell therapy for liver cirrhosis have been demonstrated in several studies. Clinical cases of mesenchymal stem cell therapy for patients with liver cirrhosis are limited and these studies lack the consistency of treatment effects. This article aimed to systematically investigate the efficacy and safety of mesenchymal stem cells in the treatment of liver cirrhosis.

METHOD

The data source included PubMed/Medline, Web of Science, EMBASE, and Cochrane Library, from inception to May 2023. Literature was screened by the PICOS principle, followed by literature quality evaluation to assess the risk of bias. Finally, the data from each study's outcome indicators were extracted for a combined analysis. Outcome indicators of the assessment included liver functions and adverse events. Statistical analysis was performed using Review Manager 5.4.

RESULTS

A total of 11 clinical trials met the selection criteria. The pooled analysis' findings demonstrated that both primary and secondary indicators had improved. Compared to the control group, infusion of mesenchymal stem cells significantly increased ALB levels in 2 weeks, 1 month, 3 months, and 6 months, and significantly decreased MELD score in 1 month, 2 months, and 6 months, according to a subgroup analysis using a random-effects model. Additionally, the hepatic arterial injection favored improvements in MELD score and ALB levels. Importantly, none of the included studies indicated any severe adverse effects.

CONCLUSION

The results showed that mesenchymal stem cell was effective and safe in the treatment of liver cirrhosis, improving liver function (such as a decrease in MELD score and an increase in ALB levels) in patients with liver cirrhosis and exerting protective effects on complications of liver cirrhosis and the incidence of hepatocellular carcinoma. Although the results of the subgroup analysis were informative for the selection of mesenchymal stem cells for clinical treatment, a large number of high-quality randomized controlled trials validations are still needed.

Bone Marrow Stromal Cells Sorted by Semiconducting Polymer Nanodots for Bone Repair

The use of bone marrow stromal cells (BMSCs) for bone defect repair has shown great promise due to their differentiation potential. However, isolating the BMSCs from various cell types within the bone marrow remains challenging. To tackle this issue, we utilized semiconducting polymer dots (Pdots) as markers to select the BMSCs within a specific time frame. The therapeutic efficacy of the obtained Pdot-labeled BMSCs was assessed in a bone defect model. Initially, we evaluated the binding capacity of the Pdots with four different types of cells present in the bone marrow including BMSCs, osteoblasts, macrophages, and vascular endothelial cells, in vitro. Notably, BMSCs showed the most rapid uptake of the Pdots, being labeled within only one h of coculture, while other cells took four h to become labeled. Moreover, by colocalizing the Pdots with Prrx1, Sca-1, OSX, F480, and CD105 in the bone marrow cells of monocortical tibial defect (MTD) mice in vivo, we determined the proportions of BMSCs, macrophages, and vascular endothelial cells among all labeled cells from 1 to 8 h after the Pdots injection. It was found that BMSCs have the highest proportion (92%) among all labeled cells extracted after 1 h of Pdots injection. The therapeutic efficacy of the obtained Pdots-labeled BMSCs (1 h) was assessed in a bone defect model. Results showed that the new bone accrual was significantly increased in the treatment of Pdots-labeled BMSCs compared to the bone marrow cell-treated group. Our study revealed that BMSCs screened by the Pdots could improve bone defect repair, suggesting a promising application of the Pdots in bone healing.

Potent antitumor efficacy of human dental pulp stem cells armed with YSCH-01 oncolytic adenovirus

BACKGROUND

Systemic administration of oncolytic adenovirus for cancer therapy is still a challenge. Mesenchymal stem cells as cell carriers have gained increasing attention in drug delivery due to their excellent tumor tropism, immunosuppressive modulatory effects, and paracrine effects. However, the potential of human dental pulp stem cells (hDPSCs) loaded with oncolytic adenovirus for cancer biotherapy has not been investigated yet.

METHODS

The stemness of hDPSCs was characterized by FACS analysis and Alizarin red staining, Oil Red O staining, and immunofluorescence assays. The biological fitness of hDPSCs loaded with oncolytic adenovirus YSCH-01 was confirmed by virus infection with different dosages and cell viability CCK-8 assays. Additionally, the expression of CAR receptor in hDPSCs was detected by qPCR assay. Tumor tropism of hDPSC loaded with YSCH-01 in vitro and in vivo was investigated by Transwell assays and living tumor-bearing mice imaging technology and immunohistochemistry, Panoramic scanning of frozen section slices assay analysis. Furthermore, the antitumor efficacy was observed through the different routes of YSCH-01/hPDSCs administration in SW780 and SCC152 xenograft models. The direct tumor cell-killing effect of YSCH-01/hDPSCs in the co-culture system was studied, and the supernatant of YSCH-01/hDPSCs inhibited cell growth was further analyzed by CCK-8 assays.

RESULTS

hDPSCs were found to be susceptible to infection by a novel oncolytic adenovirus named YSCH-01 and were capable of transporting this virus to tumor sites at 1000 VP/cell infectious dosage in vitro and in vivo. Moreover, it was discovered that intraperitoneal injection of hDPSCs loaded with oncolytic adenovirus YSCH-01 exhibited potential anti-tumor effects in both SW780 and SCC152 xenograft models. The crucial role played by the supernatant secretome derived from hDPSCs loaded with YSCH-01 significantly exerted a specific anti-tumor effect without toxicity for normal cells, in both an active oncolytic virus and an exogenous protein-independent manner. Furthermore, the use of hDPSCs as a cell carrier significantly reduced the required dosage of virus delivery in vivo compared to other methods.

CONCLUSIONS

These findings highlight the promising clinical potential of hDPSCs as a novel cell carrier in the field of oncolytic virus-based anti-cancer therapy.

Human Mesenchymal Stem Cells and Innovative Scaffolds for Bone Tissue Engineering Applications

Stem cell-based therapy is a significant topic in regenerative medicine, with a predominant role being played by human mesenchymal stem cells (hMSCs). The hMSCs have been shown to be suitable in regenerative medicine for the treatment of bone tissue. In the last few years, the average lifespan of our population has gradually increased. The need of biocompatible materials, which exhibit high performances, such as efficiency in bone regeneration, has been highlighted by aging. Current studies emphasize the benefit of using biomimetic biomaterials, also known as scaffolds, for bone grafts to speed up bone repair at the fracture site. For the healing of injured bone and bone regeneration, regenerative medicine techniques utilizing a combination of these biomaterials, together with cells and bioactive substances, have drawn a great interest. Cell therapy, based on the use of hMSCs, alongside materials for the healing of damaged bone, has obtained promising results. In this work, several aspects of cell biology, tissue engineering, and biomaterials applied to bone healing/regrowth will be considered. In addition, the role of hMSCs in these fields and recent progress in clinical applications are discussed. Impact Statement The restoration of large bone defects is both a challenging clinical issue and a socioeconomic problem on a global scale. Different therapeutic approaches have been proposed for human mesenchymal stem cells (hMSCs), considering their paracrine effect and potential differentiation into osteoblasts. However, different limitations are still to be overcome in using hMSCs as a therapeutic opportunity in bone fracture repair, including hMSC administration methods. To identify a suitable hMSC delivery system, new strategies have been proposed using innovative biomaterials. This review provides an update of the literature on hMSC/scaffold clinical applications for the management of bone fractures.

Hydrogel degradation promotes angiogenic and regenerative potential of cell spheroids for wound healing

Chronic nonhealing wounds are debilitating and diminish one's quality of life, necessitating the development of improved strategies for effective treatment. Biomaterial- and cell-based therapies offer an alternative treatment compared to conventional wound care for regenerating damaged tissues. Cell-based approaches frequently utilize endothelial cells (ECs) to promote vascularization and mesenchymal stromal cells (MSCs) for their potent secretome that promotes host cell recruitment. Spheroids have improved therapeutic potential over monodisperse cells, while degradable scaffolds can influence cellular processes conducive to long-term tissue regeneration. However, the role of biomaterial degradation on the therapeutic potential of heterotypic EC-MSC spheroids for wound healing is largely unknown. We formed poly(ethylene) glycol (PEG) hydrogels with varying ratios of matrix metalloproteinase (MMP)-degradable and non-degradable crosslinkers to develop three distinct constructs - fully degradable, partially degradable, and non-degradable - and interrogate the influence of degradation rate on engineered cell carriers for wound healing. We found that the vulnerability to degradation was critical for cellular proliferation, while inhibition of degradation impaired spheroid metabolic activity. Higher concentrations of degradable crosslinker promoted robust cell spreading, outgrowth, and secretion of proangiogenic cytokines (i.e., VEGF, HGF) that are critical in wound healing. The degree of degradation dictated the unique secretory profile of spheroids. When applied to a clinically relevant full-thickness ex vivo skin model, degradable spheroid-loaded hydrogels restored stratification of the epidermal layer, confirming the efficacy of scaffolds to promote wound healing. These results highlight the importance of matrix remodeling and its essential role in the therapeutic potential of heterotypic spheroids.

In Vivo Electroporation Improves Retinal Delivery of Intravitreally Injected Exosomes

Purpose: Mesenchymal stem cell (MSC)-derived exosomes are promising therapeutic agents and natural nanoscale delivery platforms for treating degenerative retinal diseases. This study investigated the effect of electroporation on the retinal delivery of intravitreally administered MSC-derived exosomes in a murine model. Methods: Exosomes isolated from adipose tissue-derived MSCs were stained with ExoGlow exosome-specific dye and administered to the right eyes of 40 Sprague-Dawley rats. Electroporation was performed in 20 rats immediately after intravitreal injection (electroporation group); 5 square pulses of 40 V/cm for 50 ms each with 950-ms intervals were administered. The remaining 20 rats were assigned to the no-electroporation group. The eyeballs were harvested 24 h later for evaluation. The total number of fluorescent particles per hyperfield was counted from the retinal flat mounts to quantify the retinal delivery of exosomes. Tissue damage after electroporation was evaluated using retinal histological sections and a terminal deoxynucleotidyl transferase-mediated deoxyuridine nick end labeling (TUNEL) assay. Results: A significantly higher number of fluorescent particles per hyperfield were observed in the retinal flat mounts of the electroporation group compared with that in the no-electroporation group (599.0 ± 307.5 vs. 376.9 ± 175.4; P = 0.013). Retinal histological sections and TUNEL assays showed no signs of tissue damage after electroporation. Conclusions: In vivo electroporation can improve the retinal delivery of intravitreally injected exosomes.

Efficient delivery of mesenchymal stem/stromal cells to injured liver by surface PEGylation

BACKGROUND

Mesenchymal stem/stromal cells (MSCs) have been used in clinical trials for various diseases. These have certain notable functions such as homing to inflammation sites, tissue repair, and immune regulation. In many pre-clinical studies, MSCs administered into peripheral veins demonstrated effective therapeutic outcomes. However, most of the intravenously administered MSCs were entrapped in the lung, and homing to target sites was less than 1%. This occurred mainly because of the adhesion of MSCs to vascular endothelial cells in the lung. To prevent this adhesion, we modified the surface of MSCs with polyethylene glycol (PEG; a biocompatible polymer) using the avidin-biotin complex (ABC) method.

METHODS

The surface of MSCs was modified with PEG using the ABC method. Then, the cell adhesion to mouse aortic endothelial cells and the tissue distribution of PEG-modified MSCs were evaluated. Moreover, the homing to the injured liver and therapeutic effect of PEG-modified MSCs were evaluated using carbon tetrachloride-induced acute liver failure model mice.

RESULTS

The PEG modification significantly suppressed the adhesion of MSCs to cultured mouse aortic endothelial cells as well as the entrapment of MSCs in the lungs after intravenous injection in mice. PEG-modified MSCs efficiently homed to the injured liver of carbon tetrachloride-induced acute liver failure model mice. More importantly, the cells significantly suppressed serum transaminase levels and leukocyte infiltration into the injured liver.

CONCLUSION

These results indicate that PEG modification to the surface of MSCs can suppress the lung entrapment of intravenously administered MSCs and improve their homing to the injured liver.

Synthesis of Bacteria-mimetic Gold Nanoparticles for Phagocytosis by Immune Cells

Cell-based carrier exhibits inherent advantages as the next generation of drug delivery system, namely high biocompatibility and physiological function. Current cell-based carriers are constructed via direct payload internalization or conjugation between cell and payload. However, the cells involved in these strategies must be firstly extracted from the body and the cell-based carrier must be prepared in vitro. Herein, we synthesize bacteria-mimetic gold nanoparticles (GNPs) for the construction of cell-based carrier in mice. Both β-cyclodextrin (β-CD)-modified GNPs and adamantane (ADA)-modified GNPs are coated by E. coli outer membrane vesicles (OMVs). The E. coli OMVs induce the phagocytosis of GNPs by circulating immune cells, leading to intracellular degradation of OMVs and subsequent supramolecular self-assembly of GNPs driven by β-CD-ADA host-guest interactions. In vivo construction of cell-based carrier based on bacteria-mimetic GNPs avoids the immunogenicity induced by allogeneic cells and restriction by the number of separated cells. Due to the inflammatory tropism, endogenous immune cells carry the intracellular GNP aggregates to the tumor tissues in vivo. Graphical overview Collect the outer membrane vesicles (OMVs) of E. coli by gradient centrifugation (a) and coat on gold nanoparticles (GNP) surface (b) to prepare OMV-coated cyclodextrin (CD)-GNPs and OMV-coated adamantane (ADA)-GNPs (c) via ultrasonic method.

Cellular Drug Delivery System for Disease Treatment

The application of variable novel drug delivery system has shown a flowering trend in recent years. Among them, the cell-based drug delivery system (DDS) utilizes the unique physiological function of cells to deliver drugs to the lesion area, which is the most complex and intelligent DDS at present. Compared with the traditional DDS, the cell-based DDS has the potential of prolonged circulation in body. Cellular DDS is expected to be the best carrier to realize multifunctional drug delivery. This paper introduces and analyzes common cellular DDSs such as blood cells, immune cells, stem cells, tumor cells and bacteria as well as relevant research examples in recent years. We hope that this review can provide a reference for future research on cell vectors and promote the innovative development and clinical transformation of cell-based DDS.

Lessons from the history of inorganic nanoparticles for inhalable diagnostics and therapeutics

The respiratory tract is one of the most accessible ones to exogenous nanoparticles, yet drug delivery by their means to it is made extraordinarily challenging because of the plexus of aerodynamic, hemodynamic and biomolecular factors at cellular and extracellular levels that synergistically define the safety and efficacy of this process. Here, the use of inorganic nanoparticles (INPs) for inhalable diagnostics and therapies of the lung is viewed through the prism of the history of studies on the interaction of INPs with the lower respiratory tract. The most conceptually and methodologically innovative and illuminative studies are referred to in the chronological order, as they were reported in the literature, and the trends in the progress of understanding this interaction of immense therapeutic and toxicological significance are being deduced from it. The most outstanding actual trends delineated include the diminishment of toxicity via surface functionalization, cell targeting, tagging and tracking via controlled binding and uptake, hybrid INP treatments, magnetic guidance, combined drug and gene delivery, use as adjuvants in inhalable vaccines, and other. Many of the understudied research directions, which have been accomplished by the nanostructured organic polymers in the pulmonary niche, are discussed. The progress in the use of INPs as inhalable diagnostics or therapeutics has been hampered by their well-recognized inflammatory potential and toxicity in the respiratory tract. However, the annual numbers of methodologically innovative studies have been on the rise throughout the past two decades, suggesting that this is a prolific direction of research, its comparatively poor commercial takings notwithstanding. Still, the lack of consensus on the effects of many INP compositions at low but therapeutically effective doses, the plethora of contradictory reports on ostensibly identical chemical compositions and NP properties, and the many cases of antagonism in combinatorial NP treatments imply that the rational design of inhalable medical devices based on INPs must rely on qualitative principles for the most part and embrace a partially stochastic approach as well. At the same time, the fact that the most studied INPs for pulmonary applications have been those with some of the thickest records of pulmonary toxicity, e.g., carbon, silver, gold, silica and iron oxide, is a silent call for the expansion of the search for new inorganic compositions for use in inhalable therapies to new territories.

Dystrophin Expressing Chimeric (DEC) Cell Therapy for Duchenne Muscular Dystrophy: A First-in-Human Study with Minimum 6 Months Follow-up

Duchenne Muscular Dystrophy (DMD) is a X-linked progressive lethal muscle wasting disease for which there is no cure. We present first-in-human study assessing safety and efficacy of novel Dystrophin Expressing Chimeric (DEC) cell therapy created by fusion of patient myoblasts with myoblasts of normal donor origin. We report here on safety and functional outcomes of the first 3 DMD patients. No study related adverse events (AE) and no serious adverse events (SAE) were observed up to 14 months after systemic-intraosseous administration of DEC01. Ambulatory patients showed improvements in functional tests (6-Minute Walk Test (6MWT), North Star Ambulatory Assessment (NSAA)) and both, ambulatory and non-ambulatory in PUL, strength and fatigue resistance which correlated with improvement of Electromyography (EMG) parameters. DEC01 therapy does not require immunosuppression, involves no risks of off target mutations, is not dependent upon the causative mutation and is therefore a universal therapy that does not use viral vectors and therefore can be readministered, if needed. This study was approved by the Bioethics Committee (approval No. 46/2019). Mechanism of action of the Dystrophin Expressing Chimeric Cell (DEC) cells created via ex vivo fusion of human myoblast from normal and DMD-affected donors. Following systemic-intraosseous administration, DEC engraft and fuse with the myoblasts of DMD patients, deliver dystrophin and improve muscle strength and function. (Created with BioRender.com).

Current progress of mesenchymal stem cell membrane-camouflaged nanoparticles for targeted therapy

Nanodrug delivery systems have been widely used in disease treatment. However, weak drug targeting, easy to be cleared by the immune system, and low biocompatibility are great obstacles for drug delivery. As an important part of cell information transmission and behavior regulation, cell membrane can be used as drug coating material which represents a promising strategy and can overcome these limitations. Mesenchymal stem cell (MSC) membrane, as a new carrier, has the characteristics of active targeting and immune escape of MSC, and has broad application potential in tumor treatment, inflammatory disease, tissue regeneration and other fields. Here, we review recent progress on the use of MSC membrane-coated nanoparticles for therapy and drug delivery, aiming to provide guidance for the design and clinical application of membrane carrier in the future.

Subaqueous free-standing 3D cell culture system for ultrafast cell compaction, mechano-inductive immune control, and improving therapeutic angiogenesis

Conventional 3D cell culture methods require a comprehensive complement in labor-intensive and time-consuming processes along with in vivo circumstantial mimicking. Here, we describe a subaqueous free-standing 3D cell culture (FS) device that can induce the omnidirectional environment and generate ultrafast human adipose-derived stem cells (hADSCs) that efficiently aggregate with compaction using acoustic pressure. The cell culture conditions were optimized using the FS device and identified the underlying molecular mechanisms. Unique phenomena in cell aggregation have led to extraordinary cellular behavior that can upregulate cell compaction, mechanosensitive immune control, and therapeutic angiogenesis. Therefore, we designated the resulting cell aggregates as "pressuroid." Notably, external acoustic stimulation produced by the FS device affected the pressuroids. Furthermore, the pressuroids exhibited upregulation in mechanosensitive genes and proteins, PIEZO1/2. CyclinD1 and PCNA, which are strongly associated with cell adhesion and proliferation, were elevated by PIEZO1/2. In addition, we found that pressuroids significantly increase angiogenic paracrine factor secretion, promote cell adhesion molecule expression, and enhance M2 immune modulation of Thp1 cells. Altogether, we have concluded that our pressuroid would suggest a more effective therapy method for future cell therapy than the conventional one.

Hollow Nanomaterials in Advanced Drug Delivery Systems: From Single- to Multiple Shells

Hollow-structured nanomaterials (HSNMs) have attracted increased interest in biomedical fields, owing to their excellent potential as drug delivery systems (DDSs) for clinical applications. Among HSNMs, hollow multi-shelled structures (HoMSs) exhibit properties such as high loading capacity, sequential drug release, and multi-functionalized modification and represent a new class of nanoplatforms for clinical applications. The remarkable properties of HoMS-based DDS can simultaneously satisfy and enhance DDSs for delivering small molecular drugs (e.g., antibiotics, chemotherapy drugs, and imaging agents) and macromolecular drugs (e.g., protein/peptide- and nucleic acid-based drugs). First, the latest research advances in delivering small molecular drugs are summarized and highlight the inherent advantages of HoMS-based DDSs for small molecular drug targeting, combining continuous therapeutic drug delivery and theranostics to optimize the clinical benefit. Meanwhile, the macromolecular drugs DDSs are in the initial development stage and currently offer limited delivery modes. There is a growing need to analyze the deficiency of other HSNMs and integrate the advantages of HSNMs, providing solutions for the safe, stable, and cascade delivery of macromolecular drugs to meet vast treatment requirements. Therefore, the latest advances in HoMS-based DDSs are comprehensively reviewed, mainly focusing on the characteristics, research progress by drug category, and future research prospects.

Helminth egg derivatives as proregenerative immunotherapies

The immune system is increasingly recognized as an important regulator of tissue repair. We developed a regenerative immunotherapy from the helminth Schistosoma mansoni soluble egg antigen (SEA) to stimulate production of interleukin (IL)-4 and other type 2-associated cytokines without negative infection-related sequelae. The regenerative SEA (rSEA) applied to a murine muscle injury induced accumulation of IL-4-expressing T helper cells, eosinophils, and regulatory T cells and decreased expression of IL-17A in gamma delta (γδ) T cells, resulting in improved repair and decreased fibrosis. Encapsulation and controlled release of rSEA in a hydrogel further enhanced type 2 immunity and larger volumes of tissue repair. The broad regenerative capacity of rSEA was validated in articular joint and corneal injury models. These results introduce a regenerative immunotherapy approach using natural helminth derivatives.

Computational modeling of multiple myeloma interactions with resident bone marrow cells

The interaction of multiple myeloma with bone marrow resident cells plays a key role in tumor progression and the development of drug resistance. The tumor cell response involves contact-mediated and paracrine interactions. The heterogeneity of myeloma cells and bone marrow cells makes it difficult to reproduce this environment in in-vitro experiments. The use of in-silico established tools can help to understand these complex problems. In this article, we present a computational model based on the finite element method to define the interactions of multiple myeloma cells with resident bone marrow cells. This model includes cell migration, which is controlled by stress-strain equilibrium, and cell processes such as proliferation, differentiation, and apoptosis. A series of computational experiments were performed to validate the proposed model. Cell proliferation by the growth factor IGF-1 is studied for different concentrations ranging from 0-10 ng/mL. Cell motility is studied for different concentrations of VEGF and fibronectin in the range of 0-100 ng/mL. Finally, cells were simulated under a combination of IGF-1 and VEGF stimuli whose concentrations are considered to be dependent on the cancer-associated fibroblasts in the extracellular matrix. Results show a good agreement with previous in-vitro results. Multiple myeloma growth and migration are shown to correlate linearly to the IGF-1 stimuli. These stimuli are coupled with the mechanical environment, which also improves cell growth. Moreover, cell migration depends on the fiber and VEGF concentration in the extracellular matrix. Finally, our computational model shows myeloma cells trigger mesenchymal stem cells to differentiate into cancer-associated fibroblasts, in a dose-dependent manner.

Advances in Understanding the Roles of Mesenchymal Stem Cells in Lung Cancer

Lung cancer is the most common and deadliest type of cancer worldwide. Research concerning lung cancer has made considerable progress in recent decades, but lung cancer remains the leading cause of malignancy-related mortality rate. Mesenchymal stem cells (MSCs) mainly exist in fat, umbilical cord blood, bone marrow, bone, and muscle. MSCs are a primary component of the tumor microenvironment (TME). Recent studies have shown that MSCs have roles in lung cancer-related proliferation, invasion, migration, and angiogenesis, but the underlying mechanisms are poorly understood. Because MSCs can migrate to the TME, there is increasing attention toward the use of MSCs in drugs or gene vectors for cancer treatment. This review summarizes the roles and effects of MSCs in lung cancer, while addressing clinical applications of MSCs in lung cancer treatment.

Cell-Based Drug Delivery Systems with Innate Homing Capability as a Novel Nanocarrier Platform

Nanoparticle-based drug delivery systems have been designed to treat various diseases. However, many problems remain, such as inadequate tumor targeting and poor therapeutic outcomes. To overcome these obstacles, cell-based drug delivery systems have been developed. Candidates for cell-mediated drug delivery include blood cells, immune cells, and stem cells with innate tumor tropism and low immunogenicity; they act as a disguise to deliver the therapeutic payload. In drug delivery systems, therapeutic agents are encapsulated intracellularly or attached to the surface of the plasma membrane and transported to the desired site. Here, we review the pros and cons of cell-based therapies and discuss their homing mechanisms in the tumor microenvironment. In addition, different strategies to load therapeutic agents inside or on the surface of circulating cells and the current applications for a wide range of disease treatments are summarized.

Impact of Nanotechnology on Differentiation and Augmentation of Stem Cells for Liver Therapy

The liver is one of the crucial organs of the body that performs hundreds of chemical reactions needed by the body to survive. It is also the largest gland of the body. The liver has multiple functions, including the synthesis of chemicals, metabolism of nutrients, and removal of toxins. It also acts as a storage unit. The liver has a unique ability to regenerate itself, but it can lead to permanent damage if the injury is beyond recovery. The only possible treatment of severe liver damage is liver transplant which is a costly procedure and has several other drawbacks. Therefore, attention has been shifted towards the use of stem cells that have shown the ability to differentiate into hepatocytes. Among the numerous kinds of stem cells (SCs), the mesenchymal stem cells (MSCs) are the most famous. Various studies suggest that an MSC transplant can repair liver function, improve the signs and symptoms, and increase the chances of survival. This review discusses the impact of combining stem cell therapy with nanotechnology. By integrating stem cell science and nanotechnology, the information about stem cell differentiation and regulation will increase, resulting in a better comprehension of stem cell-based treatment strategies. The augmentation of SCs with nanoparticles has been shown to boost the effect of stem cell-based therapy. Also, the function of green nanoparticles in liver therapies is discussed.

Nanotechnology-based cell-mediated delivery systems for cancer therapy and diagnosis

The global prevalence of cancer is increasing, necessitating new additions to traditional treatments and diagnoses to address shortcomings such as ineffectiveness, complications, and high cost. In this context, nano and microparticulate carriers stand out due to their unique properties such as controlled release, higher bioavailability, and lower toxicity. Despite their popularity, they face several challenges including rapid liver uptake, low chemical stability in blood circulation, immunogenicity concerns, and acute adverse effects. Cell-mediated delivery systems are important topics to research because of their biocompatibility, biodegradability, prolonged delivery, high loading capacity, and targeted drug delivery capabilities. To date, a variety of cells including blood, immune, cancer, and stem cells, sperm, and bacteria have been combined with nanoparticles to develop efficient targeted cancer delivery or diagnosis systems. The review paper aimed to provide an overview of the potential applications of cell-based delivery systems in cancer therapy and diagnosis.

Microcapsule-Based Dose-Dependent Regulation of the Lifespan and Behavior of Adipose-Derived MSCs as a Cell-Mediated Delivery System: In Vitro Study

The development of “biohybrid” drug delivery systems (DDS) based on mesenchymal stem/stromal cells (MSCs) is an important focus of current biotechnology research, particularly in the areas of oncotheranostics, regenerative medicine, and tissue bioengineering. However, the behavior of MSCs at sites of inflammation and tumor growth is relevant to potential tumor transformation, immunosuppression, the inhibition or stimulation of tumor growth, metastasis, and angiogenesis. Therefore, the concept was formulated to control the lifespan of MSCs for a specific time sufficient for drug delivery to the target tissue by varying the number of internalized microcontainers. The current study addressed the time-dependent in vitro assessment of the viability, migration, and division of human adipose-derived MSCs (hAMSCs) as a function of the dose of internalized polyelectrolyte microcapsules prepared using a layer-by-layer technique. Polystyrene sulfonate (PSS)—poly(allylamine hydrochloride) (PAH)-coated spherical micrometer-sized (diameter ~2−3 µm) vaterite (CaCO3) microcapsules (PAH-PSS)6 with the capping PSS layer were prepared after dissolution of the CaCO3 core template. The Cell-IQ phase contrast imaging results showed that hAMSCs internalized all (PAH-PSS)6 microcapsules saturating the intercellular medium (5−90 particles per cell). A strong (r > 0.7) linear dose-dependent and time-dependent (up to 8 days) regression was observed between the in vitro decrease in cell viability and the number of internalized microvesicles. The approximate time-to-complete-death of hAMSCs at different concentrations of microcapsules in culture was 428 h (1:5 ratio), 339 h (1:10), 252 h (1:20), 247 h (1:45), and 170 h (1:90 ratio). By varying the number of microcontainers loaded into the cells (from 1:10 to 1:90), a dose-dependent exponential decrease in both the movement rate and division rate of hAMSCs was observed. A real-time cell analysis (RTCA) of the effect of (PAH-PSS)6 microcapsules (from 1:5 to 1:20) on hAMSCs also showed a dose- and time-dependent decrease in cell longevity after a 50h study at ratios of 1:10 and 1:20. The incorporation of microcapsules (1:5, 1:20, and 1:45) resulted in a dose-dependent increase in 24−48 h secretion of GRO-α (CXCL1), MIF, and SDF-1α (CXCL12) chemokines in hAMSC culture. In turn, the normalization or inhibition of chemokine secretion occurred after 72 h, except for MIF levels below 5−20 microcapsules, which were internalized by MSCs. Thus, the proposed concept of controlling the lifespan of MSC-based DDS using a dose of internalized PAH-PSS microcapsules could be useful for biomedical applications. (PAH-PSS)6 microcapsule ratios of 1:5 and 1:10 have little effect on the lifespan of hAMSCs for a long time (up to 14−18 days), which can be recommended for regenerative therapy and tissue bioengineering associated with low oncological risk. The microcapsule ratios of 1:20 and 1:45 did not significantly restrict the migratory activity of hAMSCs-based DDS during the time interval required for tissue delivery (up to 4−5 days), followed by cell death after 10 days. Therefore, such doses of microcapsules can be used for hAMSC-based DDS in oncotheranostics.

Engineering Biomimetic Trogocytosis with Farnesylated Chemically Self-Assembled Nanorings

Inspired by the natural intercellular material-transfer process of trans-endocytosis or trogocytosis, we proposed that targeted farnesylated chemically self-assembled nanorings (f-CSANs) could serve as a biomimetic trogocytosis vehicle for engineering directional cargo transfer between cells, thus allowing cell-cell interactions to be monitored and facilitating cell-cell communications. The membranes of sender cells were stably modified by hydrophobic insertion with the targeted f-CSANs, which were efficiently transferred to receiver cells expressing the appropriate receptors by endocytosis. CSAN-assisted cell-cell cargo transfer (C4T) was demonstrated to be receptor specific and dependent on direct cell-cell interactions, the rate of receptor internalization, and the level of receptor expression. In addition, C4T was shown to facilitate cell-to-cell delivery of an apoptosis inducing drug, as wells as antisense oligonucleotides. Taken together, the C4T approach is a potentially versatile biomimetic trogocytosis platform that can be deployed as a macro-chemical biological tool for monitoring cell-cell interactions and engineering cell-cell communications.

Editing a gateway for cell therapy across the blood-brain barrier

Stem cell therapy has been shown to improve stroke outcomes in animal models and is currently advancing towards clinical practice. However, uncertainty remains regarding the optimal route for cell delivery to the injured brain. Local intracerebral injections are effective in precisely delivering cells into the stroke cavity but carry the risk of damaging adjacent healthy tissue. Systemic endovascular injections, meanwhile, are minimally invasive, but most injected cells do not cross CNS barriers and become mechanically trapped in peripheral organs. Although the blood-brain barrier and the blood-CSF barrier tightly limit the entrance of cells and molecules into the brain parenchyma, immune cells can cross these barriers especially under pathological conditions, such as stroke. Deciphering the cell surface signature and the molecular mechanisms underlying this pathophysiological process holds promise for improving the targeted delivery of systemic injected cells to the injured brain. In this review, we describe experimental approaches that have already been developed in which (i) cells are either engineered to express cell surface proteins mimicking infiltrating immune cells; or (ii) cell grafts are preconditioned with hypoxia or incubated with pharmacological agents or cytokines. Modified cell grafts can be complemented with strategies to temporarily increase the permeability of the blood-brain barrier. Although these approaches could significantly enhance homing of stem cells into the injured brain, cell entrapment in off-target organs remains a non-negligible risk. Recent developments in safety-switch systems, which enable the precise elimination of transplanted cells on the administration of a drug, represent a promising strategy for selectively removing stem cells stuck in untargeted organs. In sum, the techniques described in this review hold great potential to substantially improve efficacy and safety of future cell therapies in stroke and may be relevant to other brain diseases.

Optical Tissue Clearing to Study the Intra-Pulmonary Biodistribution of Intravenously Delivered Mesenchymal Stromal Cells and Their Interactions with Host Lung Cells

Mesenchymal stromal cells (MSCs) injected intravenously are trapped in the capillaries of the lungs and die within the first 24 h. Studying the biodistribution and fate of labelled therapeutic cells in the 3D pulmonary context is important to understand their function in this organ and gain insights into their mechanisms of action. Optical tissue clearing enables volumetric cell tracking at single-cell resolution. Thus, we compared three optical tissue-clearing protocols (Clear, Unobstructed Brain/Body Imaging Cocktails and Computational analysis (CUBIC), modified stabilised 3D imaging of solvent-cleared organs (s-DISCO) and ethyl cinnamate (ECi)) to evaluate their potential to track the biodistribution of human umbilical cord MSCs expressing the tdTomato fluorescence reporter and investigate how they interact with host cells in the mouse lung. The results showed that although CUBIC clearing is the only method that enables direct imaging of fluorescently labelled MSCs, combining s-DISCO or ECi with immunofluorescence or dye labelling allows the interaction of MSCs with endothelial and immune cells to be studied. Overall, this comparative study offers guidance on selecting an optical tissue-clearing method for cell tracking applications.

Cell-based carrier for targeted hitchhiking delivery

Drug delivery systems aim at improving drug transport efficiency and therapeutic efficacy by rational design, and current research on conventional delivery systems brings new developments for disease treatment. Recently, studies on cell-based drug delivery systems are rapidly emerging, which shows great advantages in comparison to conventional drug delivery system. The system uses cells as carriers to delivery conventional drugs or nanomedicines and shows good biocompatibility and enhanced targeting efficiency, beneficial from self component and its physiological function. The construction methodology of cell-based carrier determines the effect on the physiological functions of transporting cell and affects its clinical application. There are different strategies to prepare cell-based carrier, such as direct internalization or surface conjugation of drugs or drug loaded materials. Thus, it is necessary to fully understand the advantages and disadvantages of different strategies for constructing cell-based carrier and then to seek the appropriate construction methodology for achieving better therapeutic results based on disease characterization. We here summarize the application of different types of cell-based carriers reported in recent years and further discuss their applications in disease therapy and the dilemmas faced in clinical translation. We hope that this summary can accelerate the process of clinical translation by promoting the technology development of cell-based carrier.

Vitality-Enhanced Dual-Modal Tracking System Reveals the Dynamic Fate of Mesenchymal Stem Cells for Stroke Therapy

Mesenchymal stem cell (MSC) therapy via intravenous transplantation exhibits great potential for brain tissue regeneration, but still faces thorny clinical translation challenges as the unknown dynamic fate leads to the contentious therapeutic mechanism and the poor MSC viability in harsh lesions limits therapeutic efficiency. Here, a vitality-enhanced dual-modal tracking system is designed to improve engraftment efficiency and is utilized to noninvasively explore the fate of intravenous transplanted human umbilical cord-derived MSCs during long-term treatment of ischemic stroke. Such a system is obtained by bioorthogonally conjugating magnetic resonance imaging (MRI) contrast and near-infrared fluorescence (NIRF) imaging nanoparticles to metabolic glycoengineered MSCs with a lipoic acid-containing extracellular antioxidative protective layer. The dynamic fates of MSCs in multi-dimensional space-time evolution are digitally detailed for up to 28 days using MRI and NIRF imaging equipment, and the protective layer greatly shields MSCs from reactive oxygen spices (ROS) degradation, enhances MSC survival, and engraftment efficiency. Additionally, it is observed that the bioengineered MSCs exhibit dynamic intelligent responses corresponding to microenvironment remodeling and exert enhanced therapeutic effects. This dual-modal tracking system enables long-term tracking of MSCs while improving their viability at the lesion sites, which may serve as a valuable tool for expediting the clinical translation of MSC therapy.

Stem cells as an ideal carrier for gene therapy: A new approach to the treatment of hepatitis C virus

BACKGROUND AND AIM

Various chemical drugs have been approved for the treatment of patients with hepatitis C, but most of these treatments are costly, and also have an inadequate response and many side effects. Also, there is no effective vaccine for hepatitis C due to its high genetic diversity. In recent decades, clinical trials have grown dramatically regarding the benefits of stem cell therapy as a modulator of immune system responses and anti-inflammatory drugs. The most promising point in stem cell therapy and similar therapies is that patients with chronic pain and severe injuries are offered drug-free treatment or surgery. In the present study, we examine the various dimensions of the use of stem cells with the approach of gene therapy carriers as a new treatment method in the treatment of Hepatitis C.

METHODS

Search terms were including gene carrier, stem cell therapy, gene therapy, liver disorders, hepatitis C virus. At first, 1000 article titles related to the mentioned keywords for different diseases were found. After removing duplicate titles and items that did not match the scope of the research, articles that met the criteria for entering the research and had usable information were selected. All abstracts of selected articles were studied by researchers. In the initial review, articles related to the title were identified and categorized based on the type of challenge.

CONCLUSION

Gene therapy, either directly and in vivo or indirectly and in vitro, requires carriers (vectors) to transfer the gene. These carriers are divided into two groups, viral and non-viral. In indirect gene therapy, living cells are isolated from a person's body and genetically modified. Stem cells have the properties to transfer the desired genes to the patient's body, including the ability to proliferate for a long time and differentiate into the tissue cells in which they are located.

Long-Term Biodistribution and Safety of Human Dystrophin Expressing Chimeric Cell Therapy After Systemic-Intraosseous Administration to Duchenne Muscular Dystrophy Model

Duchenne muscular dystrophy (DMD) is a lethal disease caused by X-linked mutations in the dystrophin gene. Dystrophin deficiency results in progressive degeneration of cardiac, respiratory and skeletal muscles leading to premature death due to cardiopulmonary complications. Currently, no cure exists for DMD. Based on our previous reports confirming a protective effect of human dystrophin expressing chimeric (DEC) cell therapy on cardiac, respiratory, and skeletal muscle function after intraosseous administration, now we assessed long-term safety and biodistribution of human DEC therapy for potential clinical applications in DMD patients. Safety of different DEC doses (1 × 10⁶ and 5 × 10⁶) was assessed at 180 days after systemic-intraosseous administration to mdx/scid mice, a model of DMD. Assessments included: single cell gel electrophoresis assay (COMET assay) to confirm lack of genetic toxicology, magnetic resonance imaging (MRI) for tumorigenicity, and body, muscle and organ weights. Human DEC biodistribution to the target (heart, diaphragm, gastrocnemius muscle) and non-target (blood, bone marrow, lung, liver, spleen) organs was detected by flow cytometry assessment of HLA-ABC markers. Human origin of dystrophin was verified by co-localization of dystrophin and human spectrin by immunofluorescence. No complications were observed after intraosseous transplant of human DEC. COMET assay of donors and fused DEC cells confirmed lack of DNA damage. Biodistribution analysis of HLA-ABC expression revealed dose-dependent presence of human DEC cells in target organs, whereas negligible presence was detected in non-target organs. Human origin of dystrophin in the heart, diaphragm and gastrocnemius muscle was confirmed by co-localization of dystrophin expression with human spectrin. MRI revealed no evidence of tumor formation. Body mass and muscle and organ weights were stable and comparable to vehicle controls, further confirming DEC safety at 180 days post- transplant. This preclinical study confirmed long-term local and systemic safety of human DEC therapy at 180 days after intraosseous administration. Thus, DEC can be considered as a novel myoblast based advanced therapy medicinal product for DMD patients.

Adipose Tissue-Derived Mesenchymal Stromal/Stem Cells, Obesity and the Tumor Microenvironment of Breast Cancer

Simple Summary

Adipose tissue is the major microenvironment of breast cancer. Adipose tissue-derived mesenchymal stromal/stem cells (ASCs/MSCs) are key players in adipose tissue. ASCs/MSCs, particularly in the obese state, are critical in remodeling the tumor microenvironment and promoting breast cancer progression. In this review, we have addressed the impact of obesity on ASCs/MSCs, summarized the crosstalk between ASCs/MSCs and breast cancer cells, discussed related molecular mechanisms, and highlighted related research perspectives.

Abstract

Breast cancer is the most frequently diagnosed cancer and a common cause of cancer-related death in women. It is well recognized that obesity is associated with an enhanced risk of more aggressive breast cancer as well as reduced patient survival. Adipose tissue is the major microenvironment of breast cancer. Obesity changes the composition, structure, and function of adipose tissue, which is associated with inflammation and metabolic dysfunction. Interestingly, adipose tissue is rich in ASCs/MSCs, and obesity alters the properties and functions of these cells. As a key component of the mammary stroma, ASCs play essential roles in the breast cancer microenvironment. The crosstalk between ASCs and breast cancer cells is multilateral and can occur both directly through cell–cell contact and indirectly via the secretome released by ASC/MSC, which is considered to be the main effector of their supportive, angiogenic, and immunomodulatory functions. In this narrative review, we aim to address the impact of obesity on ASCs/MSCs, summarize the current knowledge regarding the potential pathological roles of ASCs/MSCs in the development of breast cancer, discuss related molecular mechanisms, underline the possible clinical significance, and highlight related research perspectives. In particular, we underscore the roles of ASCs/MSCs in breast cancer cell progression, including proliferation and survival, angiogenesis, migration and invasion, the epithelial–mesenchymal transition, cancer stem cell development, immune evasion, therapy resistance, and the potential impact of breast cancer cells on ASCS/MSCs by educating them to become cancer-associated fibroblasts. We conclude that ASCs/MSCs, especially obese ASCs/MSCs, may be key players in the breast cancer microenvironment. Targeting these cells may provide a new path of effective breast cancer treatment.

State-of-the-art of ultrasound-triggered drug delivery from ultrasound-responsive drug carriers

INTRODUCTION

The development of new tools to locally and non-invasively transferring therapeutic substances at the desired site in deep living tissue has been a long sought-after goal within the drug delivery field. Among the established methods, ultrasound (US) with US-responsive carriers holds great promise and demonstrates on-demand delivery of a variety of functional substances with spatial precision of several millimeters in deep-seated tissues in animal models and humans. These properties have motivated several explorations of US with US responsive carriers as a modality for neuromodulation and the treatment of various diseases, such as stroke and cancer.

AREAS COVERED

This article briefly discussed three specific mechanisms that enhance in vivo drug delivery via US with US-responsive carriers: 1) permeabilizing cellular membrane, 2) increasing the permeability of vessels, and 3) promoting cellular endocytotic uptake. Besides, a series of US-responsive drug carriers are discussed, with an emphasis on the relation between structural feature and therapeutic outcome.

EXPERT OPINION

This article summarized current development for each of US-responsive drug carrier, focusing on the routes of enhancing delivery and applications. The mechanisms of interaction between US-responsive carriers and US energy, such as cavitation, hyperthermia, and reactive oxygen species, as well as how these interactions can improve drug delivery into target cell/tissue. It can be expected that there are serval efforts to further identification of US-responsive particles, design of novel US waveform sequence, and survey of optimal combination between US parameters and US-responsive carriers for better controlling the spatiotemporal drug release profile, stability, and safety in vivo. The authors believe these will provide novel tools for precisely designing treatment strategies and significantly benefit the clinical management of several diseases.

Mesenchymal Stem/Stromal Cells May Decrease Success of Cancer Treatment by Inducing Resistance to Chemotherapy in Cancer Cells

Simple Summary

Tumours consist of different cell types and an extracellular matrix, all of which together form a complex microenvironment. The tumour microenvironment plays a critical role in various aspects of tumour development and progression. Mesenchymal stem/stromal cells (MSCs) are multipotent stem cells that have a tri-lineage differentiation capacity and are one of the key stromal cells in the tumour microenvironment. Following the interaction with cancer cells, they are transformed from naïve MSCs to tumour-associated MSCs, which substantially affect tumour growth and progression as well as the development of chemoresistance in cancer cells. The aim of this review article is to provide an overview of studies that have investigated how MSCs affect the susceptibility of cancer cells to chemotherapeutics. Their results show that MSCs protect cancer cells from chemotherapeutics by influencing several signalling pathways. This knowledge is crucial for the development of new treatment approaches that will lead to improved treatment outcomes.

Abstract

The tumour microenvironment, which is comprised of various cell types and the extracellular matrix, substantially impacts tumour initiation, progression, and metastasis. Mesenchymal stem/stromal cells (MSCs) are one of the key stromal cells in the tumour microenvironment, and their interaction with cancer cells results in the transformation of naïve MSCs to tumour-associated MSCs. The latter has an important impact on tumour growth and progression. Recently, it has been shown that they can also contribute to the development of chemoresistance in cancer cells. This review provides an overview of 42 studies published between 1 January 2001 and 1 January 2022 that examined the effect of MSCs on the susceptibility of cancer cells to chemotherapeutics. The studies showed that MSCs affect various signalling pathways in cancer cells, leading to protection against chemotherapy-induced damage. Promising results emerged from the use of inhibitors of various signalling pathways that are affected in cancer cells due to interactions with MSCs in the tumour microenvironment. These studies present a good starting point for the investigation of novel treatment approaches and demonstrate the importance of targeting the stroma in the tumour microenvironment to improve treatment outcomes.

Mesenchymal Stromal Cell Mitochondrial Transfer as a Cell Rescue Strategy in Regenerative Medicine: A Review of Evidence in Preclinical Models

Mesenchymal stromal cells (MSC) have excellent clinical potential and numerous properties that ease its clinical translation. Mitochondria play a crucial role in energy metabolism, essential for cellular activities, such as proliferation, differentiation, and migration. However, mitochondrial dysfunction can occur due to diseases and pathological conditions. Research on mitochondrial transfer from MSCs to recipient cells has gained prominence. Numerous studies have demonstrated that mitochondrial transfer led to increased adenosine triphosphate (ATP) production, recovered mitochondrial bioenergetics, and rescued injured cells from apoptosis. However, the complex mechanisms that lead to mitochondrial transfer from healthy MSCs to damaged cells remain under investigation, and the factors contributing to mitochondrial bioenergetics recovery in recipient cells remain largely ambiguous. Therefore, this review demonstrates an overview of recent findings in preclinical studies reporting MSC mitochondrial transfer, comprised of information on cell sources, recipient cells, dosage, route of administration, mechanism of transfer, pathological conditions, and therapeutic effects. Further to the above, this research discusses the potential challenges of this therapy in its clinical settings and suggestions to overcome its challenges.