A non-invasive strategy for suppressing asthmatic airway inflammation and remodeling: Inhalation of nebulized hypoxic hUCMSC-derived extracellular vesicles

Xuanhong Dingchuan Tang suppresses bronchial asthma inflammation via the microRNA-107-3p/PTGS2/MAPK axis

This study aimed to investigate the mechanism of Xuanhong Dingchuan Tang (XHDCT) in delaying bronchial asthma inflammation via the microRNA (miR)-107-3p/prostaglandin endoperoxide synthase 2 (PTGS2)/mitogen-activated protein kinase (MAPK) axis. Based on the network pharmacological analysis, XHDCT chemical constituents and targets of each chemical constituent were screened through the TCMSP database, and differential-expressed genes of bronchial asthma were obtained from the GEO database, which were intersected to get XHDCT potential anti-inflammatory targets. The key anti-inflammatory targets of XHDCT were acquired by protein-protein interaction (PPI) analysis of the candidate targets. Bronchial asthma mouse models were established and the pathological changes of lung tissues were observed. Serum IgE levels were tested. Total cells and eosinophils in bronchoalveolar lavage fluid (BALF) were counted. The expression of Th2-associated cytokines (interleukin (IL)-4, IL-5, and IL-13) and chemokines (monocyte chemoattractant protein-1 (MCP-1) and eotaxin) in BALF were measured. The targeting relationship between miR-107-3p and PTGS2 was tested. XHDCT delayed bronchial asthma inflammation in in-vivo asthma mouse models. A total of 155 active ingredients and their 341 targets were intersected with bronchial asthma-relevant genes, obtaining 20 potential targets of XHDCT for bronchial asthma treatment. Based on the PPI and "drug-component-target" network diagram, PTGS2 was found to be in a central position. PTGS2 was downregulated and miR-107-3p was upregulated in bronchial asthma mice after XHDCT treatment. PTGS2 overexpression activated the MAPK signaling pathway to promote inflammation in bronchial asthma mice, whereas inflammatory symptoms were reduced and the MAPK signaling pathway was inhibited after XHDCT treatment. miR-107-3p was an upstream regulatory miRNA for PTGS2. After miR-107-3p interference, the activation of the PTGS2/MAPK axis promoted inflammation in bronchial asthma mice, whereas the inflammatory symptoms were reduced after XHDCT treatment. XHDCT promotes anti-inflammatory effects in bronchial asthma via the miR-107-3p/PTGS2/MAPK axis.

Bidirectional modulation of extracellular vesicle-autophagy axis in acute lung injury: Molecular mechanisms and therapeutic implications

Acute lung injury (ALI), a multifactorial pathological condition, manifests through heightened inflammatory responses, compromised lung epithelial-endothelial barrier function, and oxidative stress, potentially culminating in respiratory failure and mortality. This study explores the intricate interplay between two crucial cellular mechanisms-extracellular vesicles (EVs) and autophagy-in the context of ALI pathogenesis and potential therapeutic interventions.EVs, bioactive membrane-bound structures secreted by cells, serve as versatile carriers of molecular cargo, facilitating intercellular communication and significantly influencing disease progression. Concurrently, autophagy, an essential intracellular degradation process, maintains cellular homeostasis and has emerged as a promising therapeutic target in ALI and acute respiratory distress syndrome.Our research unveils a fascinating "EV-Autophagy dual-drive pathway," characterized by reciprocal regulation between these two processes. EVs modulate autophagy activation and inhibition, while autophagy influences EV production, creating a dynamic feedback loop. This study posits that precise manipulation of this pathway could revolutionize ALI treatment strategies.By elucidating the mechanisms underlying this cellular crosstalk, we open new avenues for targeted therapies. The potential for engineered EVs to fine-tune autophagy in ALI treatment is explored, alongside innovative concepts such as EV-based vaccines for ALI prevention and management. This research not only deepens our understanding of ALI pathophysiology but also paves the way for novel, more effective therapeutic approaches in critical care medicine.

Nebulization of Hypoxic hUCMSC-EVs Attenuates Airway Epithelial Barrier Defects in Chronic Asthma Mice by Transferring CAV-1

Background

Nebulization of hypoxic human umbilical cord mesenchymal stem cell-derived extracellular vesicles (Hypo-EVs) can suppress airway inflammation and remodeling in a chronic asthmatic mouse; however, the exact mechanism remains unclear. Recently, airway epithelial barrier defects have been regarded as crucial therapeutic targets in asthma. The aim of this study was to investigate whether and how Hypo-EVs protect against the disruption of the airway epithelial barrier under asthmatic conditions.

Methods

The therapeutic effects of Hypo-EVs on airway epithelial barrier defects were evaluated in ovalbumin (OVA)-induced asthmatic mice and in IL-4 and IL-13-induced HBE135-E6E7 cell models by detecting cell monolayer leakage and junctional protein expression. The protein levels in Hypo-EVs were determined by Western blotting, and a gene knockdown approach was used to investigate the biofactors in Hypo-EVs.

Results

Nebulization of Hypo-EVs directly alleviated airway epithelial barrier defects in asthmatic mice, as evidenced by colocalization with bronchial epithelial cells, decreased albumin concentration, and increased ZO-1 and E-cadherin expression. In vitro, Hypo-EV treatment dramatically rescued the increase in airway cell permeability, and upregulated the ZO-1 and E-cadherin protein expressions. Based on WB analysis, we found that caveolin-1 (CAV-1) was strongly enriched in Hypo-EVs. The knockdown of CAV-1 protein levels in Hypo-EVs significantly impaired Hypo-EV-mediated barrier protection in vitro and in vivo. Moreover, CAV-1 knockdown significantly abolished the beneficial effects of Hypo-EVs on airway inflammation and remodeling in asthmatic mice. In addition, we showed that IL-4/IL-13-induced airway epithelial barrier defects were mainly related to activation of STAT6 phosphorylation (p-STAT6), and overexpression of CAV-1 or Hypo-EV treatment inhibited the levels of p-STAT6 in IL-4/IL-13-induced HBE135-E6E7 cells.

Conclusion

Nebulization of Hypo-EVs can attenuate airway epithelial barrier defects in asthma by delivering CAV-1 to inhibit p-STAT6 expression and may be used to treat other barrier defect diseases.

Extracellular Vesicle microRNA: A Promising Biomarker and Therapeutic Target for Respiratory Diseases

Respiratory diseases, including chronic obstructive pulmonary disease (COPD), asthma, lung cancer, and coronavirus pneumonia, present a major global health challenge. Current diagnostic and therapeutic options for these diseases are limited, necessitating the urgent development of novel biomarkers and therapeutic strategies. In recent years, microRNAs (miRNAs) within extracellular vesicles (EVs) have received considerable attention due to their crucial role in intercellular communication and disease progression. EVs are membrane-bound structures released by cells into the extracellular environment, encapsulating a variety of biomolecules such as DNA, RNA, lipids, and proteins. Specifically, miRNAs within EVs, known as EV-miRNAs, facilitate intercellular communication by regulating gene expression. The expression levels of these miRNAs can reflect distinct disease states and significantly influence immune cell function, chronic airway inflammation, airway remodeling, cell proliferation, angiogenesis, epithelial-mesenchymal transition, and other pathological processes. Consequently, EV-miRNAs have a profound impact on the onset, progression, and therapeutic responses of respiratory diseases, with great potential for disease management. Synthesizing the current understanding of EV-miRNAs in respiratory diseases such as COPD, asthma, lung cancer, and novel coronavirus pneumonia, this review aims to explore the potential of EV-miRNAs as biomarkers and therapeutic targets and examine their prospects in the diagnosis and treatment of these respiratory diseases.

Mesenchymal Stem Cell-Derived Extracellular Vesicle Therapy for Asthma in Murine Models: A Systematic Review and Meta-analysis

BACKGROUND

Asthma is a common disease, and among the most predominant causes of the years lived with disability. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) have emerged as a promising avenue for asthma management. The objective of this study is to perform a systematic review and meta-analysis of pre-clinical studies investigating the therapeutic use of MSC-EVs in murine models of asthma.

METHODS

A systematic search of electronic databases was performed. Meta-analyses were conducted on broncho-alveolar lavage fluid (BALF) cells and cytokines, as well as airway hyper-responsiveness Penh values and histological staining scores to determine the efficacy of MSC-EVs-based therapy, comparing treated rodents with untreated ones. BALF IL-4, BALF total cells, and BALF eosinophils were chosen as the primary outcomes, while airway hyper-responsiveness Penh values, BALF cytokines excluding IL-4, and histological staining scores were chosen as secondary outcomes.

RESULTS

A total of 19 eligible studies were included in the current systematic review, with 9 assessing BALF IL-4, 11 assessing BALF total cells, and 10 assessing BALF eosinophils. Pooled Hedges' g (p-value) for each outcome was - 4.407 (< 0.001), -4.976 (< 0.001), and - 4.071 (< 0.001), showing that MSC-EVs therapy inhibits asthma pathology. Changes in secondary outcomes also indicated a reduction in inflammation, goblet cell hyperplasia, and airway hyper-responsiveness. Subgroup analyses did not reveal significant disparities between the type of rodents and administration routes, and meta-regressions were only significant for MSC-EVs source and dose in the IL-4 meta-analysis, and for administration frequency and time from the last challenge to sacrifice in the BALF total cell meta-analysis.

CONCLUSION

This review highlights the current pre-clinical evidence of MSC-EVs therapy for asthma and finds its application ameliorates multiple aspects of asthma's pathology. We further underline the importance of MSC-EVs source, dose, administration frequency, and timing on the therapeutic effect and warrant further investigation and clinical translation to assess the best treatment regimen and to gauge the efficacy of EV therapy in human asthma cases.

Therapeutic Efficacy of Interferon-Gamma and Hypoxia-Primed Mesenchymal Stromal Cells and Their Extracellular Vesicles: Underlying Mechanisms and Potentials in Clinical Translation

Multipotent mesenchymal stromal cells (MSCs) hold promises for cell therapy and tissue engineering due to their self-renewal and differentiation abilities, along with immunomodulatory properties and trophic factor secretion. Extracellular vesicles (EVs) from MSCs offer similar therapeutic effects. However, MSCs are heterogeneous and lead to variable outcomes. In vitro priming enhances MSC performance, improving immunomodulation, angiogenesis, proliferation, and tissue regeneration. Various stimuli, such as cytokines, growth factors, and oxygen tension, can prime MSCs. Two classical priming methods, interferon-gamma (IFN-γ) and hypoxia, enhance MSC immunomodulation, although standardized protocols are lacking. This review discusses priming protocols, highlighting the most commonly used concentrations and durations, along with mechanisms and in vivo therapeutics effects of primed MSCs and their EVs. The feasibility of up-scaling their production was also discussed. The review concluded that priming with IFN-γ or hypoxia (alone or in combination with other factors) boosted the immunomodulation capability of MSCs and their EVs, primarily via the JAK/STAT and PI3K/AKT and Leptin/JAK/STAT and TGF-β/Smad signalling pathways, respectively. Incorporating priming in MSC and EV production enables translation into cell-based or cell-free therapies for various disorders.

Advances in the application of extracellular vesicles derived from three-dimensional culture of stem cells

Stem cells (SCs) have been used therapeutically for decades, yet their applications are limited by factors such as the risk of immune rejection and potential tumorigenicity. Extracellular vesicles (EVs), a key paracrine component of stem cell potency, overcome the drawbacks of stem cell applications as a cell-free therapeutic agent and play an important role in treating various diseases. However, EVs derived from two-dimensional (2D) planar culture of SCs have low yield and face challenges in large-scale production, which hinders the clinical translation of EVs. Three-dimensional (3D) culture, given its ability to more realistically simulate the in vivo environment, can not only expand SCs in large quantities, but also improve the yield and activity of EVs, changing the content of EVs and improving their therapeutic effects. In this review, we briefly describe the advantages of EVs and EV-related clinical applications, provide an overview of 3D cell culture, and finally focus on specific applications and future perspectives of EVs derived from 3D culture of different SCs.

The safety and potential efficacy of exosomes overexpressing CD24 (EXO-CD24) in mild-moderate COVID-19 related ARDS

INTRODUCTION

EXO-CD24 are exosomes genetically manipulated to over-express Cluster of Differentiation (CD) 24. It consists of two breakthrough technologies: CD24, the drug, as a novel immunomodulator that is smarter than steroids without any side effects, and exosomes as the ideal natural drug carrier.

METHODS

A randomized, single blind, dose-finding phase IIb trial in hospitalized patients with mild to moderate Coronavirus disease 2019 (COVID-19) related Acute Respiratory Distress Syndrome (ARDS) was carried out in two medical centers in Athens. Patients received either 109 or 1010 exosome particles of EXO-CD24, daily, for five consecutive days and monitored for 28 days. Efficacy was assessed at day 7 among 91 patients who underwent randomization. The outcome was also compared in a post-hoc analysis with an income control group (n = 202) that fit the inclusion and exclusion criteria.

RESULTS

The mean age was 49.4 (± 13.2) years and 74.4% were male. By day 7, 83.7% showed improved respiratory signs and 64% had better oxygen saturation (SpO2) (p < 0.05). There were significant reductions in all inflammatory markers, most notably in C-reactive protein (CRP), lactate dehydrogenase (LDH), ferritin, fibrinogen and an array of cytokines. Conversely, levels of the anti-inflammatory cytokine Interleukin-10 (IL-10) were increased (p < 0.05). Of all the documented adverse events, none were considered treatment related. No drug-drug interactions were noted. Two patients succumbed to COVID-19. Post-hoc analysis revealed that EXO-CD24 patients exhibited greater improvements in clinical and laboratory outcomes compared to an observational income control group.

CONCLUSIONS

EXO-CD24 presents a promising therapeutic approach for hyper-inflammatory state and in particular ARDS. Its unique combination of exosomes, as a drug carrier, and CD24, as an immunomodulator, coupled with inhalation administration, warrants further investigation in a larger, international, randomized, quadri-blind trial against a placebo.

Mesenchymal Stromal Cell Therapy for Thoracic Surgeons: An Update

Stem cells are undifferentiated cells presenting extensive self-renewal features and the ability to differentiate "in vitro" and "in vivo" into a range of lineage cells, like chondrogenic, osteogenic and adipogenic lineages when cultured in specific inducing media. Two major domains of clinical applications of stem cells in thoracic surgery have been investigated: regenerative medicine, which is a section of translational research in tissue engineering focusing on the replacement, renewal or regeneration of cells, tissues and organs to re-establish damaged physiologic functions; drug loading and delivery, representing a new branch proposing stem cells as carriers to provide selected districts with anti-cancer agents for targeted treatments.