Transplantation of ACE2- Mesenchymal Stem Cells Improves the Outcome of Patients with COVID-19 Pneumonia

Potential therapeutic effects and nano-based delivery systems of mesenchymal stem cells and their isolated exosomes to alleviate acute respiratory distress syndrome caused by COVID-19

The severe respiratory effects of the coronavirus disease 2019 (COVID-19) pandemic have necessitated the immediate development of novel treatments. The majority of COVID-19-related fatalities are due to acute respiratory distress syndrome (ARDS). Consequently, this virus causes massive and aberrant inflammatory conditions, which must be promptly managed. Severe respiratory disorders, notably ARDS and acute lung injury (ALI), may be treated safely and effectively using cell-based treatments, mostly employing mesenchymal stem cells (MSCs). Since the high potential of these cells was identified, a great deal of research has been conducted on their use in regenerative medicine and complementary medicine. Multiple investigations have demonstrated that MSCs and their products, especially exosomes, inhibit inflammation. Exosomes serve a critical function in intercellular communication by transporting molecular cargo from donor cells to receiver cells. MSCs and their derived exosomes (MSCs/MSC-exosomes) may improve lung permeability, microbial and alveolar fluid clearance, and epithelial and endothelial repair, according to recent studies. This review focuses on COVID-19-related ARDS clinical studies involving MSCs/MSC-exosomes. We also investigated the utilization of Nano-delivery strategies for MSCs/MSC-exosomes and anti-inflammatory agents to enhance COVID-19 treatment.

Survivin: A key apoptosis inhibitor in COVID-19 infection and its implication for treatment protocol

While the relationship between cellular apoptosis and proliferation rates in COVID patients remains underexplored in existing literature, various viruses are known to impact these fundamental process to modulate response to infection. This paper aims to assess apoptosis and proliferation rates in individuals recently infected with Coronavirus, both before and after vaccination, comparing them with healthy controls. Peripheral blood cells from newly diagnosed COVID-19 patients revealed a significant increase in proliferation and apoptosis levels in fresh lymphocytes and granulocytes compared to healthy donors. Notably, as none of the patients were under corticosteroid therapy or cytotoxic drugs, the study underscores the critical role of white blood (WBC) apoptosis in viral pathogenesis, potentially contributing significantly to COVID-19's pathogenicity. Elevated levels of soluble Fas ligand (FaSL) and the pro-inflatmmatory cytokine IL-38 were identified in COVID-19 patients, indicating potential immune dysregulation. Furthermore, individual who received the vaccine or recovered from COVID-19 exhibited higher survivin rates, suggesting a protective role for survivin in migitating lung damage. These findings suggest the prospect of developing a strategy to prevent WBC apoptosis, offering potential benefits in averting lymphopenia associated with severe COVID-19 ouctomes.

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.

Mesenchymal stromal cell therapy for COVID-19 acute respiratory distress syndrome: a double-blind randomised controlled trial

Mesenchymal stromal cells (MSC) have immunomodulatory and tissue-regenerative properties and have shown promising results in acute respiratory distress syndrome (ARDS) of multiple causes, including COVID-19. We conducted a randomised (1:1), placebo-controlled, double-blind clinical trial to assess the efficacy and safety of one bone marrow-derived MSC infusion in twenty patients with moderate to severe ARDS caused by COVID-19. The primary endpoint (increase in PaO2/FiO2 ratio from baseline to day 7, MSC 83.3 versus placebo 57.6) was not statistically significant, although a clinical improvement at day 7 in the WHO scale was observed in MSC patients (5, 50% vs 0, 0%, p = 0.033). Median time to discontinuation of supplemental oxygen was also shorter in the experimental arm (14 versus 23 days, p = 0.007), resulting in a shorter hospital stay (17.5 versus 28 days, p = 0.042). No significant differences were observed for other efficacy or safety secondary endpoints. No infusion or treatment-related serious adverse events occurred during the one-year follow-up. This study did not meet the primary endpoint of PaO2/FiO2 increase by day 7, although it suggests that MSC are safe in COVID-19 ARDS and may accelerate patients' clinical recovery and hospital discharge. Larger studies are warranted to elucidate their role in ARDS and other inflammatory lung disorders.Trial Registration: EudraCT Number: 2020-002193-27, registered on July 14th, 2020, https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-002193-27/ES . NCT number: NCT04615429, registered on November 4th, 2020, https://clinicaltrials.gov/ct2/show/NCT04615429 .

Challenges of mesenchymal stem cells in the clinical treatment of COVID-19

The 2019 coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has brought an enormous public health burden to the global society. The duration of the epidemic, the number of infected people, and the widespread of the epidemic are extremely rare in modern society. In the initial stage of infection, people generally show fever, cough, and dyspnea, which can lead to pneumonia, acute respiratory syndrome, kidney failure, and even death in severe cases. The strong infectivity and pathogenicity of SARS-CoV-2 make it more urgent to find an effective treatment. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with the potential for self-renewal and multi-directional differentiation. They are widely used in clinical experiments because of their low immunogenicity and immunomodulatory function. Mesenchymal stem cell-derived exosomes (MSC-Exo) can play a physiological role similar to that of stem cells. Since the COVID-19 pandemic, a series of clinical trials based on MSC therapy have been carried out. The results show that MSCs are safe and can significantly improve patients' respiratory function and prognosis of COVID-19. Here, the effects of MSCs and MSC-Exo in the treatment of COVID-19 are reviewed, and the clinical challenges that may be faced in the future are clarified.

Recent progress in mesenchymal stem cell-based therapy for acute lung injury

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are life-threatening diseases in critically ill patients. Although pathophysiology of ALI/ARDS has been investigated in many studies, effective therapeutic strategies are still limited. Mesenchymal stem cell (MSC)-based therapy is emerging as a promising therapeutic intervention for patients with ALI. During the last two decades, researchers have focused on the efficacy and mechanism of MSC application in ALI animal models. MSC derived from variant resources exhibited therapeutic effects in preclinical studies of ALI with different mechanisms. Based on this, clinical studies on MSC treatment in ALI/ARDS has been tried recently, especially in COVID-19 caused lung injury. Emerging clinical trials of MSCs in treating COVID-19-related conditions have been registered in past two years. The advantages and potential of MSCs in the defense against COVID-19-related ALI or ARDS have been confirmed. This review provides a brief overview of recent research progress in MSC-based therapies in preclinical study and clinical trials in ALI treatment, as well as the underlying mechanisms.

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.

Protective potential of mesenchymal stem cells against COVID-19 during pregnancy

SARS-CoV-2 causes COVID-19. COVID-19 has led to severe clinical illnesses and an unprecedented death toll. The virus induces immune inflammatory responses specifically cytokine storm in lungs. Several published reports indicated that pregnant females are less likely to develop severe symptoms compared with non-pregnant. Putative protective role of maternal blood circulating fetal mesenchymal stem cells (MSCs) has emerged and have been put forward as an explanation to alleviated symptoms. MSCs with immune-modulatory, anti-inflammatory and anti-viral roles, hold great potential for the treatment of COVID-19. MSCs could be an alternative to treat infections resulting from the SARS-CoV-2 and potential future outbreaks. This review focuses on the MSCs putative protective roles against COVID-19 in pregnant females.

A Review of the Evidence for Tryptophan and the Kynurenine Pathway as a Regulator of Stem Cell Niches in Health and Disease

Stem cells are ubiquitously found in various tissues and organs in the body, and underpin the body's ability to repair itself following injury or disease initiation, though repair can sometimes be compromised. Understanding how stem cells are produced, and functional signaling systems between different niches is critical to understanding the potential use of stem cells in regenerative medicine. In this context, this review considers kynurenine pathway (KP) metabolism in multipotent adult progenitor cells, embryonic, haematopoietic, neural, cancer, cardiac and induced pluripotent stem cells, endothelial progenitor cells, and mesenchymal stromal cells. The KP is the major enzymatic pathway for sequentially catabolising the essential amino acid tryptophan (TRP), resulting in key metabolites including kynurenine, kynurenic acid, and quinolinic acid (QUIN). QUIN metabolism transitions into the adjoining de novo pathway for nicotinamide adenine dinucleotide (NAD) production, a critical cofactor in many fundamental cellular biochemical pathways. How stem cells uptake and utilise TRP varies between different species and stem cell types, because of their expression of transporters and responses to inflammatory cytokines. Several KP metabolites are physiologically active, with either beneficial or detrimental outcomes, and evidence of this is presented relating to several stem cell types, which is important as they may exert a significant impact on surrounding differentiated cells, particularly if they metabolise or secrete metabolites differently. Interferon-gamma (IFN-γ) in mesenchymal stromal cells, for instance, highly upregulates rate-limiting enzyme indoleamine-2,3-dioxygenase (IDO-1), initiating TRP depletion and production of metabolites including kynurenine/kynurenic acid, known agonists of the Aryl hydrocarbon receptor (AhR) transcription factor. AhR transcriptionally regulates an immunosuppressive phenotype, making them attractive for regenerative therapy. We also draw attention to important gaps in knowledge for future studies, which will underpin future application for stem cell-based cellular therapies or optimising drugs which can modulate the KP in innate stem cell populations, for disease treatment.

Immunomodulation of adipose-derived mesenchymal stem cells on peripheral blood mononuclear cells in colorectal cancer patients with COVID-19

BACKGROUND

Accumulating evidence has shown that adipose tissue-derived mesenchymal stem cells (ADSCs) are an effective therapeutic approach for managing coronavirus disease 2019 (COVID-19); however, further elucidation is required to determine their underlying immunomodulatory effect on the mRNA expression of T helper cell-related transcription factors (TFs) and cytokine release in peripheral blood mononuclear cells (PBMCs).

AIM

To investigate the impact of ADSCs on the mRNA expression of TFs and cytokine release in PBMCs from colorectal cancer (CRC) patients with severe COVID-19 (CRC+ patients).

METHODS

PBMCs from CRC+ patients (PBMCs-C+) and age-matched CRC patients (PBMCs-C) were stimulated and cultured in the presence/absence of ADSCs. The mRNA levels of T-box TF TBX21 (T-bet), GATA binding protein 3 (GATA-3), RAR-related orphan receptor C (RORC), and forkhead box P3 (FoxP3) in the PBMCs were determined by reverse transcriptase-polymerase chain reaction. Culture supernatants were evaluated for levels of interferon gamma (IFN-γ), interleukin 4 (IL-4), IL-17A, and transforming growth factor beta 1 (TGF-β1) using an enzyme-linked immunosorbent assay.

RESULTS

Compared with PBMCs-C, PBMCs-C+ exhibited higher mRNA levels of T-bet and RORC, and increased levels of IFN-γ and IL-17A. Additionally, a significant decrease in FoxP3 mRNA and TGF-β1, as well as an increase in T-bet/GATA-3, RORC/FoxP3, IFN-γ/IL-4, and IL-17A/TGF-β1 ratios were observed in PBMCs-C+. Furthermore, ADSCs significantly induced a functional regulatory T cell (Treg) subset, as evidenced by an increase in FoxP3 mRNA and TGF-β1 release levels. This was accompanied by a significant decrease in the mRNA levels of T-bet and RORC, release of IFN-γ and IL-17A, and T-bet/GATA-3, RORC/FoxP3, IFN-γ/IL-4, and IL-17A/TGF-β1 ratios, compared with the PBMCs-C+alone.

CONCLUSION

The present in vitro studies showed that ADSCs contributed to the immunosuppressive effects on PBMCs-C+, favoring Treg responses. Thus, ADSC-based cell therapy could be a beneficial approach for patients with severe COVID-19 who fail to respond to conventional therapies.

Management of oxidative stress for cell therapy through combinational approaches of stem cells, antioxidants, and photobiomodulation

Over the recent decades, stem cell-based therapies have been considered as a beneficial approach for the treatment of various diseases. In these types of therapies, the stem cells and their products are used as treating agents. Despite the helpful efficacy of stem cell-based therapies, there may be challenges. Oxidative stress (OS) is one of these challenges that can affect the therapeutic properties of stem cells. Therefore, it seems that employing strategies for the reduction of OS in combination with stem cell therapy can lead to better results of these therapies. Based on the available evidence, antioxidant therapy and photobiomodulation (PBM) are strategies that can regulate the OS in the cells. Antioxidant therapy is a method in which various antioxidants are used in the therapeutic processes. PBM is also the clinical application of light that gained importance in medicine. Antioxidants and PBM can regulate OS by the effect on mitochondria as an important source of OS in the cells. Considering the importance of OS in pathologic pathways and its effect on the treatment outcomes of stem cells, in the present review first the stem cell therapy and effects of OS on this type of therapy are summarized. Then, antioxidant therapy and PBM as approaches for reducing OS with a focus on mitochondrial function are discussed. Also, a novel combination treatment with the hope of achieving better and more stable outcomes in the treatment process of diseases is proposed.

Stem Cell Extracellular Vesicles as Anti-SARS-CoV-2 Immunomodulatory Therapeutics: A Systematic Review of Clinical and Preclinical Studies

BACKGROUND

COVID-19 rapidly escalated into a worldwide pandemic with elevated infectivity even from asymptomatic patients. Complications can lead to severe pneumonia and acute respiratory distress syndrome (ARDS), which are the main contributors to death. Because of their regenerative and immunomodulatory capacities, stem cells and their derived extracellular vesicles (EVs) are perceived as promising therapies against severe pulmonary conditions, including those associated with COVID-19. Herein, we evaluate the safety and efficacy of stem cell EVs in treating COVID-19 and complicating pneumonia, acute lung injury, and ARDS. We also cover relevant preclinical studies to recapitulate the current progress in stem cell EV-based therapy.

METHODS

Using PubMed, Cochrane Central Register of Controlled Trials, Scopus, and Web of Science, we searched for all English-language published studies (2000-2023) that used stem cell EVs as a therapy for COVID-19, ARDS, or pneumonia. The risk of bias (ROB) was assessed for all studies.

RESULTS

Forty-eight studies met our inclusion criteria. Various-sized EVs derived from different types of stem cells were reported as a potentially safe and effective therapy to attenuate the cytokine storm induced by COVID-19. EVs alleviated inflammation and regenerated the alveolar epithelium by decreasing apoptosis, proinflammatory cytokines, neutrophil infiltration, and M2 macrophage polarization. They also prevented fibrin production and promoted the production of anti-inflammatory cytokines and endothelial cell junction proteins.

CONCLUSION

Similar to their parental cells, stem cell EVs mediate lung tissue regeneration by targeting multiple pathways and thus hold promise in promoting the recovery of COVID-19 patients and improving the survival rate of severely affected patients.

Vascular Alterations Following COVID-19 Infection: A Comprehensive Literature Review

SARS-CoV-2, the causative agent of the ongoing COVID-19 pandemic, has revealed a broader impact beyond the respiratory system, predominantly affecting the vascular system with various adverse manifestations. The infection induces endothelial dysfunction and immune system dysregulation, creating an inflammatory and hypercoagulable state. It affects both microvasculature and macrovasculature, leading to thromboembolic events, cardiovascular manifestations, impaired arterial stiffness, cerebrovascular complications, and nephropathy, as well as retinopathy-frequently observed in cases of severe illness. Evidence suggests that SARS-CoV-2 infection may result in persistent effects on the vascular system, identified as long-term COVID-19. This is characterized by prolonged inflammation, endotheliopathy, and an increased risk of vascular complications. Various imaging modalities, histopathological studies, and diagnostic tools such as video capillaroscopy and magnetic resonance imaging have been employed to visualize vascular alterations. This review aims to comprehensively summarize the evidence concerning short and long-term vascular alterations following COVID-19 infection, investigating their impact on patients' prognosis, and providing an overview of preventive strategies to mitigate associated vascular complications.

Adipose-derived stromal vascular fraction cells to treat long-term pulmonary sequelae of coronavirus disease 2019: 12-month follow-up

BACKGROUND AIMS

Long coronavirus disease (COVID) is estimated to occur in up to 20% of patients with coronavirus disease 2019 (COVID-19) infections, with many having persistent pulmonary symptoms. Mesenchymal stromal cells (MSCs) have been shown to have powerful immunomodulatory and anti-fibrotic properties. Autologous adipose-derived (AD) stromal vascular fraction (SVF) contains MSC and other healing cell components and can be obtained by small-volume lipoaspiration and administered on the same day. This study was designed to study the safety of AD SVF infused intravenously to treat the pulmonary symptoms of long COVID.

METHODS

Five subjects with persistent cough and dyspnea after hospitalization and subsequent discharge for COVID-19 pneumonia were treated with 40 million intravenous autologous AD SVF cells and followed for 12 months, to include with pulmonary function tests and computed tomography scans of the lung.

RESULTS

SVF infusion was safe, with no significant adverse events related to the infusion out to 12 months. Four subjects had improvements in pulmonary symptoms, pulmonary function tests, and computed tomography scans, with some improvement noted as soon as 1 month after SVF treatment.

CONCLUSIONS

It is not possible to distinguish between naturally occurring improvement or improvement caused by SVF treatment in this small, uncontrolled study. However, the results support further study of autologous AD SVF as a treatment for long COVID.

Mesenchymal stem cell-derived exosomes: Characteristics and applications in disease pathology and management

Mesenchymal stem cells (MSCs) possess a role in tissue regeneration and homeostasis because of inherent immunomodulatory capacity and the production of factors that encourage healing. There is substantial evidence that MSCs' therapeutic efficacy is primarily determined by their paracrine function including in cancers. Extracellular vesicles (EVs) are basic paracrine effectors of MSCs that reside in numerous bodily fluids and cell homogenates and play an important role in bidirectional communication. MSC-derived EVs (MSC-EVs) offer a wide range of potential therapeutic uses that exceed cell treatment, while maintaining protocell function and having less immunogenicity. We describe characteristics and isolation methods of MSC-EVs, and focus on their therapeutic potential describing its roles in tissue repair, anti-fibrosis, and cancer with an emphasis on the molecular mechanism and immune modulation and clinical trials. We also explain current understanding and challenges in the clinical applications of MSC-EVs as a cell free therapy.

Identification of the Efficient Enhancer Elements in FVIII-Padua for Gene Therapy Study of Hemophilia A

Hemophilia A (HA) is a common X-linked recessive hereditary bleeding disorder. Coagulation factor VIII (FVIII) is insufficient in patients with HA due to the mutations in the F8 gene. The restoration of plasma levels of FVIII via both recombinant B-domain-deleted FVIII (BDD-FVIII) and B-domain-deleted F8 (BDDF8) transgenes was proven to be helpful. FVIII-Padua is a 23.4 kb tandem repeat mutation in the F8 associated with a high F8 gene expression and thrombogenesis. Here we screened a core enhancer element in FVIII-Padua for improving the F8 expression. In detail, we identified a 400 bp efficient enhancer element, C400, in FVIII-Padua for the first time. The core enhancer C400 extensively improved the transcription of BDDF8 driven by human elongation factor-1 alpha in HepG2, HeLa, HEK-293T and induced pluripotent stem cells (iPSCs) with different genetic backgrounds, as well as iPSCs-derived endothelial progenitor cells (iEPCs) and iPSCs-derived mesenchymal stem cells (iMSCs). The expression of FVIII protein was increased by C400, especially in iEPCs. Our research provides a novel molecular target to enhance expression of FVIII protein, which has scientific value and application prospects in both viral and nonviral HA gene therapy strategies.

Overexpression of Wnt5a promoted the protective effect of mesenchymal stem cells on Lipopolysaccharide-induced endothelial cell injury via activating PI3K/AKT signaling pathway

BACKGROUND

Lung endothelial barrier injury plays an important role in the pathophysiology of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Mesenchymal stem cells (MSCs) therapy has shown promise in ARDS treatment and restoration of the impaired barrier function. It has been reported that Wnt5a shows protective effects on endothelial cells. Therefore, the study aimed to investigate whether overexpression of Wnt5a could promote the protective effects of MSCs on Lipopolysaccharide (LPS)-induced endothelial cell injury.

METHODS

To evaluate the protective effects of MSCs overexpressing Wnt5a, we assessed the migration, proliferation, apoptosis, and angiogenic ability of endothelial cells. We assessed the transcription of protective cellular factors using qPCR and determined the molecular mechanism using Western blot analysis.

RESULTS

Overexpression of Wnt5a upregulated the transcription of protective cellular factors in MSCs. Co-culture of MSCWnt5a promoted endothelial migration, proliferation and angiogenesis, and inhibited endothelial cell apoptosis through the PI3K/AKT pathway.

CONCLUSIONS

Overexpression of Wnt5a promoted the therapeutic effect of MSCs on endothelial cell injury through the PI3K/AKT signaling. Our study provides a novel approach for utilizing genetically modified MSCs in the transplantation therapy for ARDS.

The impact understanding of exosome therapy in COVID-19 and preparations for the future approaches in dealing with infectious diseases and inflammation

Cytokine storms, which result from an abrupt, acute surge in the circulating levels of different pro-inflammatory cytokines, are one of the complications associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. This study aimed to assess the effect of exosomes on the release of pro-inflammatory cytokines in patients with coronavirus disease 2019 (COVID-19) and compare it with a control group. The cytokines evaluated in this study were TNF-α, IL-6, IL-17, and IFN-γ. The study compared the levels of these pro-inflammatory cytokines in the peripheral blood mononuclear cells (PBMCs) of five COVID-19 patients in the intensive care unit, who were subjected to both inactivated SARS-CoV-2 and exosome therapy, with those of five healthy controls. The cytokine levels were quantified using the ELISA method. The collected data was analyzed in SPSS Version 26.0 and GraphPad Prism Version 9. According to the study findings, when PBMCs were exposed to inactivated SARS-CoV-2, pro-inflammatory cytokines increased in both patients and healthy controls. Notably, the cytokine levels were significantly elevated in the COVID-19 patients compared to the control group P-values were < 0.001, 0.001, 0.008, and 0.008 for TNF-α, IL-6, IL-17, and IFN-γ, respectively. Conversely, when both groups were exposed to exosomes, there was a marked reduction in the levels of pro-inflammatory cytokines. This suggests that exosome administration can effectively mitigate the hyperinflammation induced by COVID-19 by suppressing the production of pro-inflammatory cytokines in patients. These findings underscore the potential safety and efficacy of exosomes as a therapeutic strategy for COVID-19.

COVID-19 cooling: Nanostrategies targeting cytokine storm for controlling severe and critical symptoms

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to wreak havoc worldwide, the "Cytokine Storm" (CS, also known as the inflammatory storm) or Cytokine Release Syndrome has reemerged in the public consciousness. CS is a significant contributor to the deterioration of infected individuals. Therefore, CS control is of great significance for the treatment of critically ill patients and the reduction of mortality rates. With the occurrence of variants, concerns regarding the efficacy of vaccines and antiviral drugs with a broad spectrum have grown. We should make an effort to modernize treatment strategies to address the challenges posed by mutations. Thus, in addition to the requirement for additional clinical data to monitor the long-term effects of vaccines and broad-spectrum antiviral drugs, we can use CS as an entry point and therapeutic target to alleviate the severity of the disease in patients. To effectively combat the mutation, new technologies for neutralizing or controlling CS must be developed. In recent years, nanotechnology has been widely applied in the biomedical field, opening up a plethora of opportunities for CS. Here, we put forward the view of cytokine storm as a therapeutic target can be used to treat critically ill patients by expounding the relationship between coronavirus disease 2019 (COVID-19) and CS and the mechanisms associated with CS. We pay special attention to the representative strategies of nanomaterials in current neutral and CS research, as well as their potential chemical design and principles. We hope that the nanostrategies described in this review provide attractive treatment options for severe and critical COVID-19 caused by CS.

Extracellular Vesicles: The Invisible Heroes and Villains of COVID-19 Central Neuropathology

Acknowledging the neurological symptoms of COVID-19 and the long-lasting neurological damage even after the epidemic ends are common, necessitating ongoing vigilance. Initial investigations suggest that extracellular vesicles (EVs), which assist in the evasion of the host's immune response and achieve immune evasion in SARS-CoV-2 systemic spreading, contribute to the virus's attack on the central nervous system (CNS). The pro-inflammatory, pro-coagulant, and immunomodulatory properties of EVs contents may directly drive neuroinflammation and cerebral thrombosis in COVID-19. Additionally, EVs have attracted attention as potential candidates for targeted therapy in COVID-19 due to their innate homing properties, low immunogenicity, and ability to cross the blood-brain barrier (BBB) freely. Mesenchymal stromal/stem cell (MSCs) secreted EVs are widely applied and evaluated in patients with COVID-19 for their therapeutic effect, considering the limited antiviral treatment. This review summarizes the involvement of EVs in COVID-19 neuropathology as carriers of SARS-CoV-2 or other pathogenic contents, as predictors of COVID-19 neuropathology by transporting brain-derived substances, and as therapeutic agents by delivering biotherapeutic substances or drugs. Understanding the diverse roles of EVs in the neuropathological aspects of COVID-19 provides a comprehensive framework for developing, treating, and preventing central neuropathology and the severe consequences associated with the disease.

Improvement of renal functions in mice with septic acute kidney injury using secretome of mesenchymal stem cells

Background

A potentially fatal complication of sepsis is septic acute kidney injury. Stem cell therapy is a potential new method of treating sepsis and has been applied to treat some human diseases.

Objectives

This study investigated the effects of secretome-MSCs on NGAL, CRP, NF-κB, and MMP-9 proteins, and histopathology in mice with septic AKI.

Methods

A post-test-only group design was conducted in 30 Balb/C male mice, which were randomly assigned to five groups: the control group was intraperitoneally injected with 0.5 ml of 0.9 % NaCl, the septic AKI, and the treatment groups (T1, T2, and T3) were intraperitoneally injected with 0.5 ml of 0.9 % NaCl and 0.3 mg/kg BW LPS single dose for three days. Three-day treatments of 150, 300, and 600 µl secretome-MSCs were administered intraperitoneally into the treatment groups. Furthermore, kidney and blood samples were collected for biochemical and histopathological analyses.

Results

The T1, T2, and T3 groups had lower expression of NF-κB and MMP-9 and significantly lower CRP and NGAL levels than that of septic AKI group. T1 (1.21 ± 0.19), T2 (0.75 ± 0.22), and T3 (0.38 ± 0.14) groups demonstrated lower average scores for inflammation, necrosis, hemorrhage, and degeneration compared to septic AKI group (2.17 ± 0.13).

Conclusions

Administration of 600 µl/20 g BW secretome-MSCs suppresses NF-κB and MMP-9 expression and reduces CRP and NGAL levels. Meanwhile, the 150 and 300 µl/20 g BW doses also indicated a greater improvement in renal tissue damage of mice with septic AKI.

SARS-CoV-2 Neutralization by Cell Membrane-Coated Antifouling Nanoparticles

The global outbreak of the COVID-19 pandemic has indisputably wreaked havoc on societies worldwide, compelling the scientific community to seek urgently needed therapeutic agents with low-cost and low-side effect profiles. Numerous approaches have been investigated in the quest to prevent or treat COVID-19, but many of them exhibit unwelcome side effects, such as dysfunctional viral immune responses and inflammation. Herein, we present the preparation of solid natural human pulmonary alveolar epithelial cell (ATII) membrane-coated PLGA NPs (PLGA NPs@ATII-M), which demonstrate remarkable affinity and competitiveness to neutralize the SARS-CoV-2 S1 protein-coated NPs (SCMMA NPs-S1), which are employed as a surrogate for coronavirus particles. In addition, we first considered the antifouling properties of these types of NPs, and we found that this membrane-coated NP formulation boasts excellent antifouling capabilities, which serve to protect their neutralization properties out of shielding by protein coronas in blood circulation. Moreover, this formulation is easily prepared and stored with a low-cost profile and exhibits good specificity, high targeting efficiency, and potentially side effect avoiding, thus making it a highly promising candidate for COVID-19 treatment.

Mesenchymal stromal cells (MSCs) as a therapeutic agent of inflammatory disease and infectious COVID-19 virus: live or dead mesenchymal?

The COVID-19 infection is a worldwide disease that causes numerous immune-inflammatory disorders, tissue damage, and lung dysfunction. COVID-19 vaccines, including those from Pfizer, AstraZeneca, and Sinopharm, are available globally as effective interventions for combating the disease. The severity of COVID-19 can be most effectively reduced by mesenchymal stromal cells (MSCs) because they possess anti-inflammatory activity and can reverse lung dysfunction. MSCs can be harvested from various sources, such as adipose tissue, bone marrow, peripheral blood, inner organs, and neonatal tissues. The regulation of inflammatory cytokines is crucial in inhibiting inflammatory diseases and promoting the presence of anti-inflammatory cytokines for infectious diseases. MSCs have been employed as therapeutic agents for tissue damage, diabetes, autoimmune diseases, and COVID-19 patients. Our research aimed to determine whether live or dead MSCs are more suitable for the treatment of COVID-19 patients. Our findings concluded that dead MSCs, when directly administered to the patient, offer advantages over viable MSCs due to their extended presence and higher levels of immune regulation, such as T-reg, B-reg, and IL-10, compared to live MSCs. Additionally, dead and apoptotic MSCs are likely to be more readily captured by monocytes and macrophages, prolonging their presence compared to live MSCs.

Mesenchymal stem cells prevent H7N9 virus infection via rejuvenating immune environment to inhibit immune-overactivity

BACKGROUND

Influenza is a clinically important infectious disease with a high fatality rate, which always results in severe pneumonia. Mesenchymal stem cells (MSCs) exhibit promising therapeutic effects on severe viral pneumonia, but whether MSCs prevent virus infection and contribute to the prevention of influenza remains unknown.

METHODS

ICR mice were pretreated with human umbilical cord (hUC) MSCs and then infected with the influenza H7N9 virus. Weight, survival days, and lung index of mice were recorded. Serum antibody against influenza H7N9 virus was detected according to the hemagglutination inhibition method. Before and after virus infection, T cell and B cell subtypes in the peripheral blood of mice were evaluated by flow cytometry. Cytokines in the supernatants of MSCs, innate immune cells, and mouse broncho alveolar lavage fluid (BALF) were determined by enzyme-linked immunosorbent assay (ELISA) or Luminex Assay.

RESULTS

Pretreatment with MSCs protected mice against influenza H7N9 virus infection. Weight loss, survival rate, and structural and functional damage to the lungs of infected mice were significantly improved. Mechanistically, MSCs modulated T lymphocyte response in virus-infected mice and inhibited the cGAS/STING pathway. Importantly, the protective effect of MSCs was mediated by cell-to-cell communications and attenuation of cytokine storm caused by immune overactivation.

Umbilical cord MSC-derived exosomes improve alveolar macrophage function and reduce LPS-induced acute lung injury

Acute lung injury (ALI) is a severe condition that can progress to acute respiratory distress syndrome (ARDS), with a high mortality rate. Currently, no specific and compelling drug treatment plan exists. Mesenchymal stem cells (MSCs) have shown promising results in preclinical and clinical studies as a potential treatment for ALI and other lung-related conditions due to their immunomodulatory properties and ability to regenerate various cell types. The present study focuses on analyzing the role of umbilical cord MSC (UC-MSC))-derived exosomes in reducing lipopolysaccharide-induced ALI and investigating the mechanism involved. The study demonstrates that UC-MSC-derived exosomes effectively improved the metabolic function of alveolar macrophages and promoted their shift to an anti-inflammatory phenotype, leading to a reduction in ALI. The findings also suggest that creating three-dimensional microspheres from the MSCs first can enhance the effectiveness of the exosomes. Further research is needed to fully understand the mechanism of action and optimize the therapeutic potential of MSCs and their secretome in ALI and other lung-related conditions.

Potentials of Stem Cell Therapy in Patients Infected with COVID- 19: A Systematic Review

INTRODUCTION

In the present study, we have examined different aspects and potentials of stem cells for the management of patients infected with COVID-19.

BACKGROUND

The novel coronavirus disease (COVID-19) has been reported in most of the countries and territories (>230) of the world with .686 million confirmed cases (as of Apr. 22, 2023). While the scientific community is working to develop vaccines and develop drugs against the COVID-19 pandemic, novel alternative therapies may reduce the mortality rate. Recently, the application of stem cells for critically ill COVID-19 patients in a small group of patients has been examined.

METHODS

We searched PubMed, Web of Science, and Google Scholar up to July 2022. Those studies that reviewed COVID-19 and cell therapy potentials were entered into the study. Moreover, some recently published patents were exploited and reviewed. Patentscope, USPTO, Espacenet, Free Patents Online, and Google Patents were used for patent searches.

RESULTS

Cell-based therapy as a modality of regenerative medicine is considered one of the most promising disciplines in the fields of modern science and medicine. Such an advanced technology offers endless possibilities for transformative and potentially curative treatments for some of the most life-threatening diseases. This therapeutic tool can be useful to reduce the rate of mortality. There have been several published patents for different stem cell therapy platforms in recent years.

CONCLUSION

Stem cell therapy could be considered a safe and effective therapeutic strategy to reduce death cases in patients infected with COVID-19. Besides, stem cell therapy might increase the pulmonary functions in the patients, it suppresses the occurring inflammations and ameliorates the symptoms.

The bone-liver interaction modulates immune and hematopoietic function through Pinch-Cxcl12-Mbl2 pathway

Mesenchymal stromal cells (MSCs) are used to treat infectious and immune diseases and disorders; however, its mechanism(s) remain incompletely defined. Here we find that bone marrow stromal cells (BMSCs) lacking Pinch1/2 proteins display dramatically reduced ability to suppress lipopolysaccharide (LPS)-induced acute lung injury and dextran sulfate sodium (DSS)-induced inflammatory bowel disease in mice. Prx1-Cre; Pinch1f/f; Pinch2-/- transgenic mice have severe defects in both immune and hematopoietic functions, resulting in premature death, which can be restored by intravenous injection of wild-type BMSCs. Single cell sequencing analyses reveal dramatic alterations in subpopulations of the BMSCs in Pinch mutant mice. Pinch loss in Prx1+ cells blocks differentiation and maturation of hematopoietic cells in the bone marrow and increases production of pro-inflammatory cytokines TNF-α and IL-1β in monocytes. We find that Pinch is critical for expression of Cxcl12 in BMSCs; reduced production of Cxcl12 protein from Pinch-deficient BMSCs reduces expression of the Mbl2 complement in hepatocytes, thus impairing the innate immunity and thereby contributing to infection and death. Administration of recombinant Mbl2 protein restores the lethality induced by Pinch loss in mice. Collectively, we demonstrate that the novel Pinch-Cxcl12-Mbl2 signaling pathway promotes the interactions between bone and liver to modulate immunity and hematopoiesis and may provide a useful therapeutic target for immune and infectious diseases.

Mesenchymal Stem Cells Therapy for COVID-19: From Basic Research to Clinical Trial

The novel pathogenic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), a serious challenge for human health. In severe cases, patients suffer from acute respiratory distress syndrome even organ failure, usually owing to the dysregulated immune response and widespread inflammation. Considering that there is no known cure for COVID-19 despite the increased morbidity and mortality rate of COVID-19, modalities targeting immunity and inflammation may be promising therapeutics against COVID-19. Mesenchymal stem cells (MSCs) possessing immunomodulatory, anti-inflammatory, anti-apoptotic, and antiviral properties, can be of potential benefit to a subset of severe and critically ill patients with COVID-19. In the present study, we described the underlying mechanisms of MSCs therapy and provided a thorough research study on the recent clinical trials of MSCs for SARS-CoV-2 infection.

Role of Hedgehog Signaling Pathways in Multipotent Mesenchymal Stem Cells Differentiation

Multipotent mesenchymal stem cells (MSCs) have high self-renewal and multi-lineage differentiation potentials and low immunogenicity, so they have attracted much attention in the field of regenerative medicine and have a promising clinical application. MSCs originate from the mesoderm and can differentiate not only into osteoblasts, cartilage, adipocytes, and muscle cells but also into ectodermal and endodermal cell lineages across embryonic layers. To design cell therapy for replacement of damaged tissues, it is essential to understand the signaling pathways, which have a major impact on MSC differentiation, as this will help to integrate the signaling inputs to initiate a specific lineage. Hedgehog (Hh) signaling plays a vital role in the development of various tissues and organs in the embryo. As a morphogen, Hh not only regulates the survival and proliferation of tissue progenitor and stem populations but also is a critical moderator of MSC differentiation, involving tri-lineage and across embryonic layer differentiation of MSCs. This review summarizes the role of Hh signaling pathway in the differentiation of MSCs to mesodermal, endodermal, and ectodermal cells.

Safety of multiple intravenous infusions of adipose-derived mesenchymal stem cells for hospitalized cases of COVID-19: a randomized controlled trial

Objective

The purpose of the study was to assess the safety of allogeneic, Hope Biosciences Adipose Derived Mesenchymal Stem Cells (HB-adMSCs) for the treatment of hospitalized subjects with COVID-19.

Methods

N = 48 patients were randomly assigned to HB-adMSC (100 MM) or placebo group. Four intravenous infusions of HB-adMSCs or saline were administered at days 0, 3, 7, 10. The primary safety endpoint was incidence of adverse and serious adverse events (AE/SAEs); secondary endpoints were incidence of specific AEs and alterations in hematology, biochemistry, and coagulation parameters.

Results

Majority of AEs were mild in severity. HB-adMSC group showed a higher incidence of cardiopulmonary failure, anemia, anxiety, and diarrhea, while placebo group showed a higher incidence of headaches, fatigue, and chest discomfort (posterior probabilities ≥80%). Deaths were attributed to severe complications due to COVID-19 and were unrelated to study drug. No AEs were attributed to the treatment. Hematology and coagulation panel alterations were not associated with HB-adMSCs. Analyses of inflammatory markers showed increased levels of interleukin-6 and C-reactive protein over time in HB-adMSC group (posterior probabilities ≥78%).

Conclusion

Multiple infusions of 100MM allogeneic HB-adMSCs were considered safe for the study population. More research is needed to determine the safety of MSC therapy.

Clinical trial registration

(www.ClinicalTrials.gov) identifier NCT04362189.

Mesenchymal Stem Cell-Based Therapies in the Post-Acute Neurological COVID Syndrome: Current Landscape and Opportunities

One of the main concerns related to SARS-CoV-2 infection is the symptoms that could be developed by survivors, known as long COVID, a syndrome characterized by persistent symptoms beyond the acute phase of the infection. This syndrome has emerged as a complex and debilitating condition with a diverse range of manifestations affecting multiple organ systems. It is increasingly recognized for affecting the Central Nervous System, in which one of the most prevalent manifestations is cognitive impairment. The search for effective therapeutic interventions has led to growing interest in Mesenchymal Stem Cell (MSC)-based therapies due to their immunomodulatory, anti-inflammatory, and tissue regenerative properties. This review provides a comprehensive analysis of the current understanding and potential applications of MSC-based interventions in the context of post-acute neurological COVID-19 syndrome, exploring the underlying mechanisms by which MSCs exert their effects on neuroinflammation, neuroprotection, and neural tissue repair. Moreover, we discuss the challenges and considerations specific to employing MSC-based therapies, including optimal delivery methods, and functional treatment enhancements.

Innate immune responses to SARS-CoV-2

This chapter provides an overview of the innate immune response to SARS-CoV-2, focusing on the recognition, activation, and evasion strategies employed by the virus. The innate immune system plays a crucial role in the early defense against viral infections, and understanding its response to SARS-CoV-2 is essential for developing effective therapeutic approaches. The chapter begins by explaining the basics of the innate immune system, including its components and salient features. It discusses the various pattern recognition receptors involved in recognizing SARS-CoV-2, such as toll-like receptors, RIG-I-like receptors, NOD-like receptors, and other cytosolic sensors. The binding and entry of the virus into host cells and subsequent activation of innate immune cells, including neutrophils, monocytes, macrophages, dendritic cells, NK cells, and ILCs, are explored. Furthermore, the secretion of key cytokines and chemokines, including type I interferons, IL-6, IL-17, and TNF-alpha, is discussed as part of the innate immune response. The concept of PANoptosis, involving programmed cell death mechanisms, is introduced as a significant aspect of the response to SARS-CoV-2. The chapter also addresses the innate immune evasion strategies employed by SARS-CoV-2, which allow the virus to evade or subvert the host immune response, contributing to viral persistence. Understanding these strategies is crucial for developing targeted therapies against the virus.

Therapeutic efficacy and promise of stem cell-derived extracellular vesicles in Alzheimer's disease and other aging-related disorders

The term extracellular vesicles (EVs) refers to a variety of heterogeneous nanovesicles secreted by almost all cell types, primarily for intercellular communication and maintaining cellular homeostasis. The role of EVs has been widely reported in the genesis and progression of multiple pathological conditions, and these vesicles are suggested to serve as 'liquid biopsies'. In addition to their use as biomarkers, EVs secreted by specific cell types, especially with stem cell properties, have shown promise as cell-free nanotherapeutics. Stem cell-derived EVs (SC-EVs) have been increasingly used as an attractive alternative to stem cell therapies and have been reported to promote regeneration of aging-associated tissue loss and function. SC-EVs treatment ameliorates brain and peripheral aging, reproductive dysfunctions and inhibits cellular senescence, thereby reversing several aging-related disorders and dysfunctions. The anti-aging therapeutic potential of SC-EVs depends on multiple factors, including the type of stem cells, the age of the source stem cells, and their physiological state. In this review, we briefly describe studies related to the promising effects of SC-EVs against various aging-related pathologies, and then we focus in-depth on the therapeutic benefits of SC-EVs against Alzheimer's disease, one of the most devastating neurodegenerative diseases in elderly individuals. Numerous studies in transgenic mouse models have reported the usefulness of SC-EVs in targeting the pathological hallmarks of Alzheimer's disease, including amyloid plaques, neurofibrillary tangles, and neuroinflammation, leading to improved neuronal protection, synaptic plasticity, and cognitive measures. Cell culture studies have further identified the underlying molecular mechanisms through which SC-EVs reduce amyloid beta (Aβ) levels or shift microglia phenotype from pro-inflammatory to anti-inflammatory state. Interestingly, multiple routes of administration, including nasal delivery, have confirmed that SC-EVs could cross the blood-brain barrier. Due to this, SC-EVs have also been tested to deliver specific therapeutic cargo molecule/s (e.g., neprilysin) to the brain. Despite these promises, several challenges related to quality control, scalability, and biodistribution remain, hindering the realization of the vast clinical promise of SC-EVs.

Bone Marrow Mesenchymal Stem Cell-Derived Extracellular Vesicle Infusion for the Treatment of Respiratory Failure From COVID-19: A Randomized, Placebo-Controlled Dosing Clinical Trial

BACKGROUND

Bone marrow mesenchymal stem cell (BM-MSC)-derived extracellular vesicles (ExoFlo) convey the immunomodulatory and regenerative properties of intact BM-MSCs. This study aimed to determine the safety and efficacy of ExoFlo as treatment for moderate to severe ARDS in patients with severe COVID-19.

RESEARCH QUESTION

Do two doses of ExoFlo safely reduce mortality in COVID-19-associated moderate to severe ARDS compared with placebo?

STUDY DESIGN AND METHODS

A prospective phase 2 multicenter double-anonymized randomized placebo-controlled dosing trial was conducted at five sites across the United States with infusions of placebo, 10 mL of ExoFlo, or 15 mL of ExoFlo on days 1 and 4. Patients (N = 102) with COVID-19-associated moderate to severe ARDS were enrolled and randomized to treatment. Adverse events were documented throughout the study. The primary outcome measure was all-cause 60-day mortality rate. Secondary outcomes included time to death (overall mortality); the incidence of treatment-emergent serious adverse events; proportion of discharged patients at 7, 30, and 60 days; time to hospital discharge; and ventilation-free days.

RESULTS

No treatment-related adverse events were reported. Mortality (60-day) in the intention-to-treat population was reduced with 15 mL ExoFlo mixed with 85 mL normal saline (ExoFlo-15) compared with placebo (not significant, χ2, P = .1343). For the post hoc subgroup analyses, 60-day mortality was decreased with ExoFlo-15 compared with placebo (relative risk, 0.385; 95% CI, 0.159-0.931; P = .0340; n = 50). With ExoFlo-15, a relative risk of 0.423 (95% CI, 0.173-1.032; P = .0588; n = 24) was determined for participants aged 18 to 65 years with moderate to severe ARDS. Ventilation-free days improved with ExoFlo-15 (P = .0455; n = 50) for all participants aged 18 to 65 years.

INTERPRETATION

The 15 mL dose of ExoFlo was found to be safe in patients with severe or critical COVID-19-associated respiratory failure. In participants aged 18 to 65 years, the risk reduction in 60-day mortality was further improved from subjects of all ages in the intention-to-treat population after two doses of 15 mL of ExoFlo compared with placebo.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT04493242; URL: www.

CLINICALTRIALS

gov.

A 'one stone, two birds' approach with mesenchymal stem cells for acute respiratory distress syndrome and Type II diabetes mellitus

This review explores the intricate relationship between acute respiratory distress syndrome (ARDS) and Type II diabetes mellitus (T2DM). It covers ARDS epidemiology, etiology and pathophysiology, along with current treatment trends and challenges. The lipopolysaccharides (LPS) role in ARDS and its association between non-communicable diseases and COVID-19 are discussed. The review highlights the therapeutic potential of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) for ARDS and T2DM, emphasizing their immunomodulatory effects. This review also underlines how T2DM exacerbates ARDS pathophysiology and discusses the potential of hUC-MSCs in modulating immune responses. In conclusion, the review highlights the multidisciplinary approach to managing ARDS and T2DM, focusing on inflammation, oxidative stress and potential therapy of hUC-MSCs in the future.

Mesenchymal Stem Cells in the Pathogenesis and Therapy of Autoimmune and Autoinflammatory Diseases

Mesenchymal stem cells (MSCs) modulate immune responses and maintain self-tolerance. Their trophic activities and regenerative properties make them potential immunosuppressants for treating autoimmune and autoinflammatory diseases. MSCs are drawn to sites of injury and inflammation where they can both reduce inflammation and contribute to tissue regeneration. An increased understanding of the role of MSCs in the development and progression of autoimmune disorders has revealed that MSCs are passive targets in the inflammatory process, becoming impaired by it and exhibiting loss of immunomodulatory activity. MSCs have been considered as potential novel cell therapies for severe autoimmune and autoinflammatory diseases, which at present have only disease modifying rather than curative treatment options. MSCs are emerging as potential therapies for severe autoimmune and autoinflammatory diseases. Clinical application of MSCs in rare cases of severe disease in which other existing treatment modalities have failed, have demonstrated potential use in treating multiple diseases, including rheumatoid arthritis, systemic lupus erythematosus, myocardial infarction, liver cirrhosis, spinal cord injury, multiple sclerosis, and COVID-19 pneumonia. This review explores the biological mechanisms behind the role of MSCs in autoimmune and autoinflammatory diseases. It also covers their immunomodulatory capabilities, potential therapeutic applications, and the challenges and risks associated with MSC therapy.

Stem cell-based therapy for COVID-19

While The World Health Organization (WHO) has announced that COVID-19 is no longer a public health emergency of international concern(PHEIC), the risk of reinfection and new emerging variants still makes it crucial to study and work towards the prevention of COVID-19. Stem cell and stem cell-like derivatives have shown some promising results in clinical trials and preclinical studies as an alternative treatment option for the pulmonary illnesses caused by the COVID-19 and can be used as a potential vaccine. In this review, we will systematically summarize the pathophysiological process and potential mechanisms underlying stem cell-based therapy in COVID-19, and the registered COVID-19 clinical trials, and engineered extracellular vesicle as a potential vaccine for preventing COVID-19.

Navigating the Post-COVID-19 Immunological Era: Understanding Long COVID-19 and Immune Response

The COVID-19 pandemic has affected the world unprecedentedly, with both positive and negative impacts. COVID-19 significantly impacted the immune system, and understanding the immunological consequences of COVID-19 is essential for developing effective treatment strategies. The purpose of this review is to comprehensively explore and provide insights into the immunological aspects of long COVID-19, a phenomenon where individuals continue to experience a range of symptoms and complications, even after the acute phase of COVID-19 infection has subsided. The immune system responds to the initial infection by producing various immune cells and molecules, including antibodies, T cells, and cytokines. However, in some patients, this immune response becomes dysregulated, leading to chronic inflammation and persistent symptoms. Long COVID-19 encompasses diverse persistent symptoms affecting multiple organ systems, including the respiratory, cardiovascular, neurological, and gastrointestinal systems. In the post-COVID-19 immunological era, long COVID-19 and its impact on immune response have become a significant concern. Post-COVID-19 immune pathology, including autoimmunity and immune-mediated disorders, has also been reported in some patients. This review provides an overview of the current understanding of long COVID-19, its relationship to immunological responses, and the impact of post-COVID-19 immune pathology on patient outcomes. Additionally, the review addresses the current and potential treatments for long COVID-19, including immunomodulatory therapies, rehabilitation programs, and mental health support, all of which aim to improve the quality of life for individuals with long COVID-19. Understanding the complex interplay between the immune system and long COVID-19 is crucial for developing targeted therapeutic strategies and providing optimal care in the post-COVID-19 era.

Immune-Cell-Based Therapy for COVID-19: Current Status

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic. The interplay between innate and adaptive immune responses plays a crucial role in managing COVID-19. Cell therapy has recently emerged as a promising strategy to modulate the immune system, offering immense potential for the treatment of COVID-19 due to its customizability and regenerative capabilities. This review provides an overview of the various subsets of immune cell subsets implicated in the pathogenesis of COVID-19 and a comprehensive summary of the current status of immune cell therapy in COVID-19 treatment.

Adipose-derived, autologous mesenchymal stem cell therapy for patients with post-COVID-19 syndrome: an intermediate-size expanded access program

BACKGROUND

Evolving mutations of the novel coronavirus continue to fuel up the pandemic. The virus affects the human respiratory system along with other body systems, causing several sequelae in the survivors of the disease, presented as post-COVID-19 syndrome or long-COVID-19. This protocol utilized Hope Biosciences' autologous, adipose-derived mesenchymal stem cells (HB-adMSCs) to evaluate safety and efficacy of HB-adMSC therapy to improve signs and symptoms associated with post-COVID-19 syndrome.

METHODS

Ten eligible subjects with post-COVID-19 syndrome were enrolled in the program for a duration of 40 weeks who received 5 intravenous infusions of 2 × 108 autologous HB-adMSCs each at week 0, 2, 6, 10 and 14 with a follow-up at week 18 and end of the study at week 40. Safety assessments included incidence of adverse and serious adverse events along with the laboratory measures of hematologic, hepatic, and renal function. Efficacy was examined by quality-of-life assessments, fatigue assessments, Visual analog scale (VAS) of symptoms and monitoring of respiration and oxygen saturation rates.

RESULTS

VAS scores and Fatigue Assessment scores (FAS) showed significant improvements post-treatment (P = 0.0039, ES = 0.91) compared to baseline. Respiration rates and oxygen saturation levels that were within the normal range at the baseline remained unchanged at the end of the study (EOS). Paired comparison between baseline and EOS for short-form-36 health survey questionnaire (SF-36) scores also showed improved quality-of-life with significant improvements in individual SF-36 evaluations. Mostly mild AEs were reported during the study period with no incidence of serious AEs. Also, no detrimental effects in laboratory values were seen.

CONCLUSIONS

The results of the expanded access program indicated that treatment with autologous HB-adMSCs resulted in significant improvements in the signs and symptoms associated with post-COVID-19 syndrome as assessed by VAS and FAS scores. Additionally, improvements in the patients' quality-of-life as demonstrated using SF-36 scores that also showed significant improvements in individual scaled scores. Overall, administration of multiple infusions of autologous HB-adMSCs is safe and efficacious for improvements in the quality-of life of patients with post-COVID-19 syndrome.

TRIAL REGISTRATION

Clinical trial registration number: NCT04798066. Registered on March 15, 2021. ( https://clinicaltrials.gov/ct2/show/NCT04798066?term=hope+biosciences&cond=Post-COVID-19+Syndrome&draw=2&rank=2 ).

Complications of COVID-19 on the Central Nervous System: Mechanisms and Potential Treatment for Easing Long COVID

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invades human cells by binding to the angiotensin-converting-enzyme-2 (ACE-2) using a spike protein and leads to Coronavirus disease-2019 (COVID-19). COVID-19 primarily causes a respiratory infection that can lead to severe systemic inflammation. It is also common for some patients to develop significant neurological and psychiatric symptoms. The spread of SARS-CoV-2 to the CNS likely occurs through several pathways. Once spread in the CNS, many acute symptoms emerge, and such infections could also transpire into severe neurological complications, including encephalitis or ischemic stroke. After recovery from the acute infection, a significant percentage of patients develop "long COVID," a condition in which several symptoms of COVID-19 persist for prolonged periods. This review aims to discuss acute and chronic neurological problems after SARS-CoV-2 infection. The potential mechanisms by which SARS-CoV-2 enters the CNS and causes neuroinflammation, neuropathological changes observed in post-mortem brains of COVID-19 patients, and cognitive and mood problems in COVID-19 survivors are discussed in the initial part. The later part of the review deliberates the causes of long COVID, approaches for noninvasive tracking of neuroinflammation in long COVID patients, and the potential therapeutic strategies that could ease enduring CNS symptoms observed in long COVID.

Azithromycin alters Colony Stimulating Factor-1R (CSF-1R) expression and functional output of murine bone marrow-derived macrophages: A novel report

Antibiotic treatment may lead to side effects that require mechanistic explanation. We investigated the effect of azithromycin (AZM) treatment on bone marrow-derived macrophage (Mφ) generation, their functional output, and the subsequent effect on bacterial clearance in a mouse model of S. flexneri infection. To our fascination, AZM increased PU.1, C/EBPβ, CSF-1R/pCSF-1R expressions leading to M2-skewed in vitro BMDM generation. Altered Mφ-functions like- phagocytosis, oxidative stress generation, inflammasome-activation, cytokine release, and phenotype (pro-inflammatory-M1, anti-inflammatory-M2) even in the presence of infection were observed with AZM treatment. AZM increased CD206, egr2, arg1 (M2-marker) expression and activity while reducing CD68, inducible nitric oxide (iNOS) expression, and activity (M1-marker) in Mφs during infection. Pro-inflammatory cytokines (TNF-α, IL-12, IL-1β) were reduced and anti-inflammatory IL-10 release was augmented by AZM-treated-iMφs (aiMφs) along with decreased asc, nlrp3, aim2, nlrp1a, caspase1 expressions, and caspase3 activity signifying that aMφs/aiMφs were primed towards an anti-inflammatory phenotype. Interestingly, CSF-1R blockade increased NO, IL-12, TNF-α, IL-1β, decreased TGF-β release, and CD206 expression in aiMφs. T-cell co-stimulatory molecule cd40, cd86, and cd80 expressions were decreased in ai/aM1-Mφs and co-cultured CD8+, CD4+ T-cells had decreased proliferation, t-bet, IFN-γ, IL-17, IL-2 but increased foxp3, TGF-β, IL-4 which were rescued with CSF-1R blockade. Thus AZM affected Mφ-functions and subsequent T-cell responses independent of its antibacterial actions. This was validated in the balb/c model of S. flexneri infection. We conclude that AZM skewed BMDM generation to anti-inflammatory M2-like via increased CSF-1R expression. This warrants further investigation of AZM-induced altered-Mφ-generation during intracellular infections.

Immune and cytokine alterations and RNA-sequencing analysis in gestational tissues from pregnant women after recovery from COVID-19

BACKGROUND

COVID-19 is a global pandemic. Understanding the immune responses in pregnant women recovering from COVID-19 may suggest new therapeutic approaches.

METHODS

We performed a cross-sectional study between March 1, 2020, and September 1, 2020. Participants were assigned into the convalescent COVID-19 group if they had a previous COVID-19 infection during pregnancy or the healthy control group. RNA-Seq was performed on human umbilical cord mesenchymal stem cells (hUMSCs) and human amniotic mesenchymal stem cells (hAMSCs). Immunohistochemical staining, cytokine testing, lymphocyte subset analysis, RNA-Seq, and functional analyses were performed on the placental and umbilical cord blood (UCB) and compared between the two groups.

RESULTS

A total of 40 pregnant women were enrolled, with 13 in the convalescent group and 27 in the control group. There were 1024, 46, and 32 differentially expressed genes (DEGs) identified in the placental tissue, hUMSCs, and hAMSCs between the convalescent and control groups, respectively. Enrichment analysis showed those DEGs were associated with immune homeostasis, antiviral activity, cell proliferation, and tissue repair. Levels of IL-6, TNF-α, total lymphocyte counts, B lymphocytes, Tregs percentages, and IFN-γ expressing CD4+ and CD8+ T cells were statistically different between two groups (p ≤ 0.05). ACE2 and TMPRSS2 expressed on the placenta were not different between the two groups (p > 0.05).

CONCLUSION

Multiple changes in immune responses occurred in the placental tissue, hUMSCs, and hAMSCs after maternal recovery from COVID-19, which might imply their protective roles against COVID-19 infection.

hMSCs treatment attenuates murine herpesvirus-68 (MHV-68) pneumonia through altering innate immune response via ROS/NLRP3 signaling pathway

Immunocompromised individuals are particularly vulnerable to viral infections and reactivation, especially endogenous herpes viruses such as Epstein-Barr virus (EBV), a member of oncogenic gamma-herpesviruses, which are commonly linked to pneumonia and consequently significant morbidity and mortality. In the study of human and animal oncogenic gammaherpesviruses, the murine gamma-herpesviruses-68 (MHV-68) model has been applied, as it can induce pneumonia in immunocompromised mice. Mesenchymal stem cell (MSC) treatment has demonstrated therapeutic potential for pneumonia, as well as other forms of acute lung injury, in preclinical models. In this study, we aim to investigate the therapeutic efficacy and underlying mechanisms of human bone marrow-derived MSC (hMSC) on MHV-68-induced pneumonia. We found that intravenous administration of hMSCs significantly reduced lung damages, diminished inflammatory mediators and somehow inhibited MHV-68 replication. Furthermore, hMSCs treatment can regulate innate immune response and induce macrophage polarization from M1 to M2 phenotype, could significantly alter leukocyte infiltration and reduce pulmonary fibrosis. Our findings with co-culture system indicated that hMSCs effectively reduced the secretion of of inflammation-related factors and induced a shift in macrophage polarization, consistent with in vivo results. Further investigations revealed that hMSCs treatment suppressed the activation of macrophage ROS/NLRP3 signaling pathway in vivo and in vitro. Moreover, administration of MCC950, a selective NLRP3 inhibitor has been shown to effectively reduce ROS production and subsequently alleviate inflammation induced by MHV-68. Taken together, our work has shown that hMSCs can effectively protect mice from lethal MHV-68 pneumonia, which may throw new light on strategy for combating human EBV-associated pneumonia.

Rationale for combined therapies in severe-to-critical COVID-19 patients

An unprecedented global social and economic impact as well as a significant number of fatalities have been brought on by the coronavirus disease 2019 (COVID-19), produced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Acute SARS-CoV-2 infection can, in certain situations, cause immunological abnormalities, leading to an anomalous innate and adaptive immune response. While most patients only experience mild symptoms and recover without the need for mechanical ventilation, a substantial percentage of those who are affected develop severe respiratory illness, which can be fatal. The absence of effective therapies when disease progresses to a very severe condition coupled with the incomplete understanding of COVID-19's pathogenesis triggers the need to develop innovative therapeutic approaches for patients at high risk of mortality. As a result, we investigate the potential contribution of promising combinatorial cell therapy to prevent death in critical patients.

The promising approach of MSCs therapy for COVID-19 treatment

Several ongoing investigations have been founded on the development of an optimized therapeutic strategy for the COVID-19 virus as an undeniable acute challenge for human life. Cell-based therapy and particularly, mesenchymal stem cells (MSCs) therapy has obtained desired outcomes in decreasing the mortality rate of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), mainly owing to its immunoregulatory impact that prevents the overactivation of the immune system. Also, these cells with their multipotent nature, are capable of repairing the damaged tissue of the lung which leads to reducing the probability of acute respiratory distress syndrome (ARDS). Although this cell-based method is not quite cost-effective for developing countries, regarding its promising results in order to treat SARS-COV-2, more economical evaluation as well as clinical trials should be performed for improving this therapeutic approach. Here in this article, the functional mechanism of MSCs therapy for the treatment of COVID-19 and the clinical trials based on this method will be reviewed. Moreover, its economic efficiency will be discussed.

Safety and efficacy of mesenchymal stem cells in COVID-19 patients: A systematic review and meta-analysis

BACKGROUND

Coronavirus disease-19 (COVID-19) is a zoonotic disease that has become a global pandemic. The fast evolution of the COVID-19 pandemic and persist problems make COVID-19 highly infectious; publicly accessible literature and other sources of information continue to expand in volume. The mesenchymal stem cells (MSCs) therapy efficacy for COVID-19 is debatable.

OBJECTIVE

This systematic review and meta-analysis (SRMA) aimed to evaluate the usefulness of MSCs in treating COVID-19.

METHODS

Relevant publications were retrieved from databases up to April 30, 2022. In the case of dichotomous data, the 95% confidence intervals (CIs) and pooled risk ratio (RR) were estimated with a random effects model (REM) or fixed effects model (FEM). The pooled mean difference (MD) and 95% CIs were calculated with REM or FEM in continuous data. In the outcomes, studies with insufficient or unusable data were reported descriptively.

RESULTS

A total of eight randomized controlled trials (RCTs) with 464 people were chosen for this SRMA. Relative to the control group, mortality was significantly lower in the MSCs group (RR: 0.66, 95% CI: 0.44, 0.99, Z = 2.01, p = .04); other secondary outcomes, such as the clinical symptom improvement rate improved in the MSCs group (RR: 1.44, 95% CI: 1.05, 1.99, Z = 2.24, p = .03), clinical symptom improvement time (MD: -4.01, 95% CI: -6.33, -1.68, Z = 3.38, p = .0007), C-reactive protein (CRP) (MD: -39.16, 95% CI: -44.39, -33.94, Z = 14.70, p < .00001) and days to hospital discharge (MD: -3.83, 95% CI: -6.19, -1.48, Z = 3.19, p = .001) reduced significantly in MSCs group. However, the adverse reaction incidence did not change significantly.

CONCLUSIONS

MSCs are a viable therapy option for COVID-19 because of their safety and potential efficacy. With no significant adverse effects, MSCs can reduce mortality, clinical symptom improvement time, and days to hospital discharge, improve clinical symptoms, and reduce inflammatory cytokines CRP in COVID-19. However, further high-quality clinical studies are required to confirm these results.

Engineering Materials and Devices for the Prevention, Diagnosis, and Treatment of COVID-19 and Infectious Diseases

Following the global spread of COVID-19, scientists and engineers have adapted technologies and developed new tools to aid in the fight against COVID-19. This review discusses various approaches to engineering biomaterials, devices, and therapeutics, especially at micro and nano levels, for the prevention, diagnosis, and treatment of infectious diseases, such as COVID-19, serving as a resource for scientists to identify specific tools that can be applicable for infectious-disease-related research, technology development, and treatment. From the design and production of equipment critical to first responders and patients using three-dimensional (3D) printing technology to point-of-care devices for rapid diagnosis, these technologies and tools have been essential to address current global needs for the prevention and detection of diseases. Moreover, advancements in organ-on-a-chip platforms provide a valuable platform to not only study infections and disease development in humans but also allow for the screening of more effective therapeutics. In addition, vaccines, the repurposing of approved drugs, biomaterials, drug delivery, and cell therapy are promising approaches for the prevention and treatment of infectious diseases. Following a comprehensive review of all these topics, we discuss unsolved problems and future directions.

Advances of mesenchymal stem cells and their derived extracellular vesicles as a promising therapy for acute respiratory distress syndrome: from bench to clinic

Acute respiratory distress syndrome (ARDS) is an acute inflammatory lung injury characterized by diffuse alveolar damage. The period prevalence of ARDS was 10.4% of ICU admissions in 50 countries. Although great progress has been made in supportive care, the hospital mortality rate of severe ARDS is still up to 46.1%. Moreover, up to now, there is no effective pharmacotherapy for ARDS and most clinical trials focusing on consistently effective drugs have met disappointing results. Mesenchymal stem cells (MSCs) and their derived extracellular vesicles (EVs) have spawned intense interest of a wide range of researchers and clinicians due to their robust anti-inflammatory, anti-apoptotic and tissue regeneration properties. A growing body of evidence from preclinical studies confirmed the promising therapeutic potential of MSCs and their EVs in the treatment of ARDS. Based on the inspiring experimental results, clinical trials have been designed to evaluate safety and efficacy of MSCs and their EVs in ARDS patients. Moreover, trials exploring their optimal time window and regimen of drug administration are ongoing. Therefore, this review aims to present an overview of the characteristics of mesenchymal stem cells and their derived EVs, therapeutic mechanisms for ARDS and research progress that has been made over the past 5 years.

Clinical efficacy and safety of multipotent adult progenitor cells (invimestrocel) for acute respiratory distress syndrome (ARDS) caused by pneumonia: a randomized, open-label, standard therapy-controlled, phase 2 multicenter study (ONE-BRIDGE)

BACKGROUND

Acute respiratory distress syndrome (ARDS) is a life-threatening inflammatory lung injury with high mortality; no approved medication exists. Efficacy and safety of bone marrow-derived, allogeneic, multipotent adult progenitor cells (invimestrocel) plus standard treatment in patients with ARDS caused by pneumonia was evaluated.

METHODS

A randomized, open-label, standard therapy-controlled, phase 2 study (January 2019-September 2021) conducted in 29 centers in Japan. Patients with ARDS caused by pneumonia, with extensive early fibroproliferation on high-resolution computed tomography and low risk of systemic organ failure identified by an Acute Physiology and Chronic Health Evaluation (APACHE II) score were included. Patients were randomized 2:1 to receive a single intravenous infusion of 9.0 × 108 cells of invimestrocel (administered at a rate of up to 10 mL/min over 30-60 min by free flow) plus standard treatment (N = 20) or standard treatment (N = 10) consistent with the clinical practice guidelines of the Japanese Respiratory Society for the management of ARDS. Primary endpoint was ventilator-free days (VFDs) through day 28 after study treatment. Analysis of covariance was performed with treatment group, age, partial pressure arterial oxygen/fraction of inspired oxygen ratio, and APACHE II score as covariates.

RESULTS

Median (interquartile range) number of VFDs was numerically higher in the invimestrocel group versus standard group (20.0 [0.0-24.0] vs 11.0 [0.0-14.0]) but was not statistically significantly different (least square [LS] means [95% confidence interval (CI)]: invimestrocel group, 11.6 [6.9-16.3]; standard group, 6.2 [- 0.4 to 12.8]; LS mean difference [95% CI], 5.4 [- 1.9 to 12.8]; p = 0.1397). Ventilator weaning rate at day 28 was 65% (13/20) versus 30% (3/10), and mortality rate was 21% (4/19) versus 29% (2/7) at day 28 and 26% (5/19 patients) versus 43% (3/7 patients) at day 180, for the invimestrocel and standard groups, respectively. No allergic or serious adverse reactions were associated with invimestrocel.

CONCLUSIONS

In Japanese patients with ARDS caused by pneumonia, invimestrocel plus standard treatment resulted in no significant difference in the number of VFDs but may result in improved survival compared with standard treatment. Invimestrocel was well tolerated.

TRIAL REGISTRATION

ClinicalTrials.gov, Identifier: NCT03807804; January 8, 2019; https://clinicaltrials.gov/ct2/show/NCT03807804 .