Surfing the clinical trials of mesenchymal stem cell therapy in ischemic cardiomyopathy

Advancing cardiac regeneration through 3D bioprinting: methods, applications, and future directions

Cardiovascular diseases (CVDs) represent a paramount global mortality concern, and their prevalence is on a relentless ascent. Despite the effectiveness of contemporary medical interventions in mitigating CVD-related fatality rates and complications, their efficacy remains curtailed by an array of limitations. These include the suboptimal efficiency of direct cell injection and an inherent disequilibrium between the demand and availability of heart transplantations. Consequently, the imperative to formulate innovative strategies for cardiac regeneration therapy becomes unmistakable. Within this context, 3D bioprinting technology emerges as a vanguard contender, occupying a pivotal niche in the realm of tissue engineering and regenerative medicine. This state-of-the-art methodology holds the potential to fabricate intricate heart tissues endowed with multifaceted structures and functionalities, thereby engendering substantial promise. By harnessing the prowess of 3D bioprinting, it becomes plausible to synthesize functional cardiac architectures seamlessly enmeshed with the host tissue, affording a viable avenue for the restitution of infarcted domains and, by extension, mitigating the onerous yoke of CVDs. In this review, we encapsulate the myriad applications of 3D bioprinting technology in the domain of heart tissue regeneration. Furthermore, we usher in the latest advancements in printing methodologies and bioinks, culminating in an exploration of the extant challenges and the vista of possibilities inherent to a diverse array of approaches.

Mesenchymal stromal cells for improvement of cardiac function following acute myocardial infarction: a matter of timing

Acute myocardial infarction (AMI) is the leading cause of cardiovascular death and remains the most common cause of heart failure. Reopening of the occluded artery, i.e., reperfusion, is the only way to save the myocardium. However, the expected benefits of reducing infarct size are disappointing due to the reperfusion paradox, which also induces specific cell death. These ischemia-reperfusion (I/R) lesions can account for up to 50% of final infarct size, a major determinant for both mortality and the risk of heart failure (morbidity). In this review, we provide a detailed description of the cell death and inflammation mechanisms as features of I/R injury and cardioprotective strategies such as ischemic postconditioning as well as their underlying mechanisms. Due to their biological properties, the use of mesenchymal stromal/stem cells (MSCs) has been considered a potential therapeutic approach in AMI. Despite promising results and evidence of safety in preclinical studies using MSCs, the effects reported in clinical trials are not conclusive and even inconsistent. These discrepancies were attributed to many parameters such as donor age, in vitro culture, and storage time as well as injection time window after AMI, which alter MSC therapeutic properties. In the context of AMI, future directions will be to generate MSCs with enhanced properties to limit cell death in myocardial tissue and thereby reduce infarct size and improve the healing phase to increase postinfarct myocardial performance.

Application and challenges of stem cells in cardiovascular aging

With the rapid development of society and the economy, population aging has become a common challenge faced by many countries in the world today. Structural and functional changes in the cardiovascular system can occur with age, increasing the incidence and severity of cardiovascular diseases in older adults. Due to the limited regenerative capacity of myocardial cells, myocardial infarction and its resulting heart failure and congenital heart disease have become the number one killer of human health. At present, the treatment of cardiovascular diseases includes drug therapy and nondrug therapy. Nondrug therapy mainly includes minimally invasive interventional therapy, surgical diagnosis and treatment, and cell therapy. Long-term drug treatment may cause headache due to vasodilation, lower blood pressure, digestive system dysfunction and other side effects. Surgical treatment is traumatic, difficult to treat, and expensive. In recent years, stem cell therapy has exhibited broad application prospects in basic and clinical research on cardiovascular disease because of its plasticity, self-renewal and multidirectional differentiation potential. Therefore, this paper looks at stem cell therapy for diseases, reviews recent advances in the mechanism and clinical transformation of cardiovascular aging and related diseases in China, and briefly discusses the development trend and future prospects of cardiovascular aging research.

A review of the conservative versus invasive management of ischemic heart failure with reduced ejection fraction

Heart failure is increasing in terms of prevalence, morbidity, and mortality rates. Clinical trials and studies are focusing on heart failure as it is the destiny end-stage for several cardiovascular disorders. Recently, medical therapy has dramatically progressed with novel classes of medicines providing better quality of life and survival outcomes. However, heart failure remains a heavy impactful factor on societies and populations. Current guidelines from the American and European cardiac societies are not uniform with respect to the class and level of treatment recommendations for coronary artery disease patients with heart failure and reduced ejection fraction. The discrepancy among international recommendations, stemming from the lack of evidence from adequately powered randomized trials, challenges physicians in choosing the optimal strategy. Hybrid therapy including optimal medical therapy with revascularization strategies are commonly used for the management of ischemic heart failure. Coronary artery bypass graft (CABG) has proved its efficacy on improving long term outcome and prognosis while no large randomized clinical trials for percutaneous coronary intervention (PCI) are still available. Regardless of the lack of data and recommendations, the trends of performing PCI in ischemic heart failure prevailed over CABG whereas lesion complexity, chronic total occlusion and complete revascularization achievement are limiting factors. Lastly, regenerative medicine seems a promising approach for advanced heart failure enhancing cardiomyocytes proliferation, reverse remodeling, scar size reduction and cardiac function restoration.

Exoskeleton Partial-Coated Stem Cells for Infarcted Myocardium Restoring

The integration of abiotic materials with live cells has emerged as an exciting strategy for the control of cellular functions. Exoskeletons consisting ofmetal-organic frameworks are generated to produce partial-coated bone marrow stem cells (BMSCs) to overcome low cell survival leading to disappointing effects for cell-based cardiac therapy. Partially coated exoskeletons can promote the survival of suspended BMSCs by integrating the support of exoskeletons and unimpaired cellular properties. In addition, partial exoskeletons exhibit protective effects against detrimental environmental conditions, including reactive oxygen species, pH changes, and osmotic pressure. The partial-coated cells exhibit increased intercellular adhesion forces to aggregate and adhere, promoting cell survival and preventing cell escape during cell therapy. The exoskeletons interact with cell surface receptors integrin α5β1, leading to augmented biological functions with profitable gene expression alteration, such as Vegfa, Cxcl12, and Adm. The partial-coated BMSCs display enhanced cell retention in infarcted myocardium through non-invasive intravenous injections. The repair of myocardial infarction has been achieved with improved cardiac function, myocardial angiogenesis, proliferation, and inhibition of cell apoptosis. This discovery advances the elucidation of potential molecular and cellular mechanisms for cell-exoskeleton interactions and benefits the rational design and manufacture of next-generation nanobiohybrids.

Therapeutic Effects of Mesenchymal Stromal Cells Require Mitochondrial Transfer and Quality Control

Due to their beneficial effects in an array of diseases, Mesenchymal Stromal Cells (MSCs) have been the focus of intense preclinical research and clinical implementation for decades. MSCs have multilineage differentiation capacity, support hematopoiesis, secrete pro-regenerative factors and exert immunoregulatory functions promoting homeostasis and the resolution of injury/inflammation. The main effects of MSCs include modulation of immune cells (macrophages, neutrophils, and lymphocytes), secretion of antimicrobial peptides, and transfer of mitochondria (Mt) to injured cells. These actions can be enhanced by priming (i.e., licensing) MSCs prior to exposure to deleterious microenvironments. Preclinical evidence suggests that MSCs can exert therapeutic effects in a variety of pathological states, including cardiac, respiratory, hepatic, renal, and neurological diseases. One of the key emerging beneficial actions of MSCs is the improvement of mitochondrial functions in the injured tissues by enhancing mitochondrial quality control (MQC). Recent advances in the understanding of cellular MQC, including mitochondrial biogenesis, mitophagy, fission, and fusion, helped uncover how MSCs enhance these processes. Specifically, MSCs have been suggested to regulate peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC1α)-dependent biogenesis, Parkin-dependent mitophagy, and Mitofusins (Mfn1/2) or Dynamin Related Protein-1 (Drp1)-mediated fission/fusion. In addition, previous studies also verified mitochondrial transfer from MSCs through tunneling nanotubes and via microvesicular transport. Combined, these effects improve mitochondrial functions, thereby contributing to the resolution of injury and inflammation. Thus, uncovering how MSCs affect MQC opens new therapeutic avenues for organ injury, and the transplantation of MSC-derived mitochondria to injured tissues might represent an attractive new therapeutic approach.

Safety and outcomes analysis: transcatheter implantation of autologous angiogenic cell precursors for the treatment of cardiomyopathy

BACKGROUND

Stem cell transplantation is an emerging therapy for severe cardiomyopathy, proffering stem cell recruitment, anti-apoptosis, and proangiogenic capabilities. Angiogenic cell precursors (ACP-01) are autologous, lineage-specific, cells derived from a multipotent progenitor cell population, with strong potential to effectively engraft, form blood vessels, and support tissue survival and regeneration.

METHODS

This IRB approved outcome analysis reports upon 74 consecutive patients who failed medical management for severe cardiomyopathy, and were selected to undergo transcatheter intramyocardial or intracoronary implantation of ACP-01. Serious adverse events (SAEs) were reported. Cell analysis was conducted for each treatment. The left ventricular ejection fraction (LVEF) was measured by multi-gated acquisition scan (MUGA) or echocardiogram at 4 months ± 1.9 months and 12 months ± 5.5 months. Patients reported quality of life statements at 6 months (± 5.6 months).

RESULTS

Fifty-four of 74 patients met requirements for inclusion (48 males and five females; age 68.1 ± 11.3 years). The mean treatment cell number of 57 × 106 ACP-01 included 7.7 × 106 CD34 + and 21 × 106 CD31 + cells with 97.6% viability. SAEs included one death (previously unrecognized silent MI), ventricular tachycardia (n = 2) requiring cardioversion, and respiratory infection (n = 2). LVEF in the ischemic subgroup (n = 41) improved by 4.7% ± 9.7 from pre-procedure to the first follow-up (4 months ± 1.9 months) (p < 0.004) and by 7.2% ± 10.9 at final follow-up (n = 25) at average 12 months (p < 0.004). The non-ischemic dilated cardiomyopathy subgroup (n = 8) improved by 7.5% ± 6.0 at the first follow-up (p < 0.017) and by 12.2% ± 6.4 at final follow-up (p < 0.003, n = 6). Overall improvement in LVEF from pre-procedure to post-procedure was significant (Fisher's exact test p < 0.004). LVEF improvement was most marked in the patients with the most severe cardiomyopathy (LVEF < 20%) improving from a mean 14.6% ± 3.4% pre-procedurally to 28.4% ± 8% at final follow-up. Quality of life statements reflected improvement in 33/50 (66%), no change in 14/50 (28%), and worse in 3/50 (6%).

CONCLUSION

Transcatheter implantation of ACP-01 for cardiomyopathy is safe and improves LVEF in the setting of ischemic and non-ischemic cardiomyopathy. The results warrant further investigation in a prospective, blinded, and controlled clinical study.

TRIAL REGISTRATION

IRB from Genetic Alliance #APC01-001, approval date July 25, 2022. Cardiomyopathy is common and associated with high mortality. Stem cell transplantation is an emerging therapy. Angiogenic cell precursors (ACP-01) are lineage-specific endothelial progenitors, with strong potential for migration, engraftment, angiogenesis, and support of tissue survival and regeneration. A retrospective outcomes analysis of 53 patients with ischemic and non-ischemic dilated cardiomyopathy undergoing transcatheter implantation of ACP-01 demonstrated improvements in the left ventricular ejection fraction of 7.2% ± 10.9 (p < 0.004) and 12.2% ± 6.4, respectively, at 12 months (± 5) follow-up. Quality of life statements reflected improvement in 33/50 (66%) patients.

Mesenchymal Stem Cell-Derived Exosomes and Their MicroRNAs in Heart Repair and Regeneration

Mesenchymal stem cells (MSCs) can be differentiated into cardiac, endothelial, and smooth muscle cells. Therefore, MSC-based therapeutic approaches have the potential to deal with the aftermaths of cardiac diseases. However, transplanted stem cells rarely survive in damaged myocardium, proposing that paracrine factors other than trans-differentiation may involve in heart regeneration. Apart from cytokines/growth factors, MSCs secret small, single-membrane organelles named exosomes. The MSC-secreted exosomes are enriched in lipids, proteins, nucleic acids, and microRNA (miRNA). There has been an increasing amount of data that confirmed that MSC-derived exosomes and their active molecule microRNA (miRNAs) regulate signaling pathways involved in heart repair/regeneration. In this review, we systematically present an overview of MSCs, their cardiac differentiation, and the role of MSC-derived exosomes and exosomal miRNAs in heart regeneration. In addition, biological functions regulated by MSC-derived exosomes and exosomal-derived miRNAs in the process of heart regeneration are reviewed.

Stem cells treatment in chronic ischemic heart disease: a narrative review

Chronic ischemic heart disease remains a major cause of morbidity and mortality worldwide. Several trials have been performed to evaluate benefit of stem cells transplantation to restore cardiac function in short- and long-term period after myocardial infarction. This narrative review analyzes 24 clinical trials between 2005 and 2023 comprising 1824 patients with chronic heart disease without heart failure. Percent increase in left ventricular ejection fraction (LVEF) and decrease in New York Heart Association (NYHA) class at 6/12 months after stem cells transplantation are reported. Thirteen trials showed a statistically significant percent LVEF increase between 4% to 19% at 6/12 months after stem cells transplantation (p values from 0.05 to 0.0001). No significant differences in LVEF were observed between patients who underwent intracoronary or intramyocardial transplantation. NYHA class decrease from severe to mild/moderate was demonstrated in 10 trials reporting a significant LVEF increase. Patients transplanted with bone marrow and peripheral blood CD133+ stem cells showed a doubling of percentage LVEF increase in comparison to patients transplanted with CD133- cells. This narrative review reports the conflicting results on this topic. Multicenter randomized clinical trials should be performed to define the efficacy of stem cells transplantation in chronic ischemic heart disease.

Wnt signaling pathway inhibitor promotes mesenchymal stem cells differentiation into cardiac progenitor cells in vitro and improves cardiomyopathy in vivo

BACKGROUND

Cardiovascular diseases particularly myocardial infarction (MI) are the leading cause of mortality and morbidity around the globe. As cardiac tissue possesses very limited regeneration potential, therefore use of a potent small molecule, inhibitor Wnt production-4 (IWP-4) for stem cell differentiation into cardiomyocytes could be a promising approach for cardiac regeneration. Wnt pathway inhibitors may help stem cells in their fate determination towards cardiomyogenic lineage and provide better homing and survival of cells in vivo. Mesenchymal stem cells (MSCs) derived from the human umbilical cord have the potential to regenerate cardiac tissue, as they are easy to isolate and possess multilineage differentiation capability. IWP-4 may promote the differentiation of MSCs into the cardiac lineage.

AIM

To evaluate the cardiac differentiation ability of IWP-4 and its subsequent in vivo effects.

METHODS

Umbilical cord tissue of human origin was utilized to isolate the MSCs which were characterized by their morphology, immunophenotyping of surface markers specific to MSCs, as well as by tri-lineage differentiation capability. Cytotoxicity analysis was performed to identify the optimal concentration of IWP-4. MSCs were treated with 5 μM IWP-4 at two different time intervals. Differentiation of MSCs into cardiomyocytes was evaluated at DNA and protein levels. The MI rat model was developed. IWP-4 treated as well as untreated MSCs were implanted in the MI model, then the cardiac function was analyzed via echocardiography. MSCs were labeled with 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI) dye for tracking, while the regeneration of infarcted myocardium was examined by histology and immunohistochemistry.

RESULTS

MSCs were isolated and characterized. Cytotoxicity analysis showed that IWP-4 was non-cytotoxic at 5 μM concentration. Cardiac specific gene and protein expression analyses exhibited more remarkable results in fourteen days treated group that was eventually selected for in vivo transplantation. Cardiac function was restored in the IWP-4 treated group in comparison to the MI group. Immunohistochemical analysis confirmed the homing of pre-differentiated MSCs that were labeled with DiI cell labeling dye. Histological analysis confirmed the significant reduction in fibrotic area, and improved left ventricular wall thickness in IWP-4 treated MSC group.

CONCLUSION

Treatment of MSCs with IWP-4 inhibits Wnt pathway and promotes cardiac differentiation. These pre-conditioned MSCs transplanted in vivo improved cardiac function by cell homing, survival, and differentiation at the infarcted region, increased left ventricular wall thickness, and reduced infarct size.

Chitosan Scaffolds as Microcarriers for Dynamic Culture of Human Neural Stem Cells

Human neural stem cells (hNSCs) possess remarkable potential for regenerative medicine in the treatment of presently incurable diseases. However, a key challenge lies in producing sufficient quantities of hNSCs, which is necessary for effective treatment. Dynamic culture systems are recognized as a powerful approach to producing large quantities of hNSCs required, where microcarriers play a critical role in supporting cell expansion. Nevertheless, the currently available microcarriers have limitations, including a lack of appropriate surface chemistry to promote cell adhesion, inadequate mechanical properties to protect cells from dynamic forces, and poor suitability for mass production. Here, we present the development of three-dimensional (3D) chitosan scaffolds as microcarriers for hNSC expansion under defined conditions in bioreactors. We demonstrate that chitosan scaffolds with a concentration of 4 wt% (4CS scaffolds) exhibit desirable microstructural characteristics and mechanical properties suited for hNSC expansion. Furthermore, they could also withstand degradation in dynamic conditions. The 4CS scaffold condition yields optimal metabolic activity, cell adhesion, and protein expression, enabling sustained hNSC expansion for up to three weeks in a dynamic culture. Our study introduces an effective microcarrier approach for prolonged expansion of hNSCs, which has the potential for mass production in a three-dimensional setting.

Human Stem Cells for Cardiac Disease Modeling and Preclinical and Clinical Applications-Are We on the Road to Success?

Cardiovascular diseases (CVDs) are pointed out by the World Health Organization (WHO) as the leading cause of death, contributing to a significant and growing global health and economic burden. Despite advancements in clinical approaches, there is a critical need for innovative cardiovascular treatments to improve patient outcomes. Therapies based on adult stem cells (ASCs) and embryonic stem cells (ESCs) have emerged as promising strategies to regenerate damaged cardiac tissue and restore cardiac function. Moreover, the generation of human induced pluripotent stem cells (iPSCs) from somatic cells has opened new avenues for disease modeling, drug discovery, and regenerative medicine applications, with fewer ethical concerns than those associated with ESCs. Herein, we provide a state-of-the-art review on the application of human pluripotent stem cells in CVD research and clinics. We describe the types and sources of stem cells that have been tested in preclinical and clinical trials for the treatment of CVDs as well as the applications of pluripotent stem-cell-derived in vitro systems to mimic disease phenotypes. How human stem-cell-based in vitro systems can overcome the limitations of current toxicological studies is also discussed. Finally, the current state of clinical trials involving stem-cell-based approaches to treat CVDs are presented, and the strengths and weaknesses are critically discussed to assess whether researchers and clinicians are getting closer to success.

Human Stem Cells for Cardiac Disease Modeling and Preclinical and Clinical Applications—Are We on the Road to Success?

Cardiovascular diseases (CVDs) are pointed out by the World Health Organization (WHO) as the leading cause of death, contributing to a significant and growing global health and economic burden. Despite advancements in clinical approaches, there is a critical need for innovative cardiovascular treatments to improve patient outcomes. Therapies based on adult stem cells (ASCs) and embryonic stem cells (ESCs) have emerged as promising strategies to regenerate damaged cardiac tissue and restore cardiac function. Moreover, the generation of human induced pluripotent stem cells (iPSCs) from somatic cells has opened new avenues for disease modeling, drug discovery, and regenerative medicine applications, with fewer ethical concerns than those associated with ESCs. Herein, we provide a state-of-the-art review on the application of human pluripotent stem cells in CVD research and clinics. We describe the types and sources of stem cells that have been tested in preclinical and clinical trials for the treatment of CVDs as well as the applications of pluripotent stem-cell-derived in vitro systems to mimic disease phenotypes. How human stem-cell-based in vitro systems can overcome the limitations of current toxicological studies is also discussed. Finally, the current state of clinical trials involving stem-cell-based approaches to treat CVDs are presented, and the strengths and weaknesses are critically discussed to assess whether researchers and clinicians are getting closer to success.

Revisiting the Mesenchymal "Stem vs. Stromal" Cell Dichotomy and Its Implications for Development of Improved Potency Metrics

Mesenchymal stem/stromal cell (MSC)-based therapies have been evaluated in over 1500 human clinical trials for a diverse array of disease indication, but outcomes remain unpredictable due to knowledge gaps in the quality attributes that confer therapeutic potency onto cells and their mode of action in vivo. Based on accumulated evidence from pre-clinical models, MSCs exert therapeutic effects by repressing inflammatory and immune-mediated response via paracrine action following reprogramming by the host injury microenvironment, and by polarization of tissue resident macrophages following phagocytosis to an alternatively activated (M2) state. An important tenet of this existing paradigm is that well-established stem/progenitor functions of MSCs are independent of paracrine function and dispensable for their anti-inflammatory and immune suppressive functions. Herein, we review evidence that stem/progenitor and paracrine functions of MSCs are mechanistically linked and organized hierarchically and describe how this link may be exploited to develop metrics that predict MSC potency across a spectrum of activities and regenerative medicine applications.

Drug-based mobilisation of mesenchymal stem/stromal cells improves cardiac function post myocardial infarction

There is an unmet need for treatments that prevent the progressive cardiac dysfunction following myocardial infarction. Mesenchymal stem/stromal cells (MSCs) are under investigation for cardiac repair; however, culture expansion prior to transplantation is hindering their homing and reparative abilities. Pharmacological mobilisation could be an alternative to MSC transplantation. Here, we report that endogenous MSCs mobilise into the circulation at day 5 post myocardial infarction in male Lewis rats. This mobilisation can be significantly increased by using a combination of the FDA-approved drugs mirabegron (β3-adrenoceptor agonist) and AMD3100 (CXCR4 antagonist). Blinded cardiac magnetic resonance imaging analysis showed the treated group to have increased left ventricular ejection fraction and decreased end systolic volume at 5 weeks post myocardial infarction. The mobilised group had a significant decrease in plasma IL-6 and TNF-α levels, a decrease in interstitial fibrosis, and an increase in the border zone blood vessel density. Conditioned medium from blood-derived MSCs supported angiogenesis in vitro, as shown by tube formation and wound healing assays. Our data suggest a novel pharmacological strategy that enhances myocardial infarction-induced MSC mobilisation and improves cardiac function after myocardial infarction.

Identification MNS1, FRZB, OGN, LUM, SERP1NA3 and FCN3 as the potential immune-related key genes involved in ischaemic cardiomyopathy by random forest and nomogram

The immune molecular mechanisms involved in ischaemic cardiomyopathy (ICM) have not been fully elucidated. The current study aimed to elucidate the immune cell infiltration pattern of the ICM and identify key immune-related genes that participate in the pathologic process of the ICM. The differentially expressed genes (DEGs) were identified from two datasets (GSE42955 combined with GSE57338) and the top 8 key DEGs related to ICM were screened using random forest and used to construct the nomogram model. Moreover, the "CIBERSORT" software package was used to determine the proportion of infiltrating immune cells in the ICM. A total of 39 DEGs (18 upregulated and 21 downregulated) were identified in the current study. Four upregulated DEGs, including MNS1, FRZB, OGN, and LUM, and four downregulated DEGs, SERP1NA3, RNASE2, FCN3 and SLCO4A1, were identified by the random forest model. The nomogram constructed based on the above 8 key genes suggested a diagnostic value of up to 99% to distinguish the ICM from healthy participants. Meanwhile, most of the key DEGs presented prominent interactions with immune cell infiltrates. The RT-qPCR results suggested that the expression levels of MNS1, FRZB, OGN, LUM, SERP1NA3 and FCN3 between the ICM and control groups were consistent with the bioinformatic analysis results. These results suggested that immune cell infiltration plays a critical role in the occurrence and progression of ICM. Several key immune-related genes, including the MNS1, FRZB, OGN, LUM, SERP1NA3 and FCN3 genes, are expected to be reliable serum markers for the diagnosis of ICM and potential molecular targets for ICM immunotherapy.

Electrochemical biosensors in exosome analysis; a short journey to the present and future trends in early-stage evaluation of cancers

The tumor microenvironment consists of a multiplicity of cells such as cancer cells, fibroblasts, endothelial cells, and immune cells within the specific parenchyma. It has been indicated that cancer cells can educate other cells within the tumor niche in a paracrine manner by the release of nano-sized extracellular vesicles namely exosomes (Exo), resulting in accelerated tumor mass growth. It is suggested that exosomal cargo with remarkable information can reflect any changes in metabolic and proteomic profiles in parent tumor cells. Therefore, exosomes can be touted as prognostic, diagnostic, and therapeutic elements with specific biomarkers in patients with different tumor types. Despite the advantages, conventional exosome separation and purification protocols are time-consuming and laborious with low abnormal morphology and purity rate. During the last decades, biosensor-based modalities, as emerging instruments, have been used to detect and analyze Exo in biofluids. Due to suitable specificity, sensitivity, and real-time readout, biosensors became promising approaches for the analysis of Exo in in vitro and in vivo settings. The inherent advantages and superiority of electrochemical biosensors in the determination of tumor grade based on exosomal cargo and profile were also debated. Present and future challenges were also discussed related to the application of electrochemical biosensors in the clinical setting. In this review, the early detection of several cancer types associated with ovaries, breast, brain, colon, lungs, T and B lymphocytes, liver and rare types of cancers were debated in association with released exosomes.

Transfer of Cardiac Mitochondria Improves the Therapeutic Efficacy of Mesenchymal Stem Cells in a Preclinical Model of Ischemic Heart Disease

BACKGROUND

The use of mesenchymal stem cells (MSCs) appears to be a promising therapeutic approach for cardiac repair after myocardial infarction. However, clinical trials have revealed the need to improve their therapeutic efficacy. Recent evidence demonstrated that mitochondria undergo spontaneous transfer from damaged cells to MSCs, resulting in the activation of the cytoprotective and pro-angiogenic functions of recipient MSCs. Based on these observations, we investigated whether the preconditioning of MSCs with mitochondria could optimize their therapeutic potential for ischemic heart disease.

METHODS

Human MSCs were exposed to mitochondria isolated from human fetal cardiomyocytes. After 24 h, the effects of mitochondria preconditioning on the MSCs' function were analyzed both in vitro and in vivo.

RESULTS

We found that cardiac mitochondria-preconditioning improved the proliferation and repair properties of MSCs in vitro. Mechanistically, cardiac mitochondria mediate their stimulatory effects through the production of reactive oxygen species, which trigger their own degradation in recipient MSCs. These effects were further confirmed in vivo, as the mitochondria preconditioning of MSCs potentiated their therapeutic efficacy on cardiac function following their engraftment into infarcted mouse hearts.

CONCLUSIONS

The preconditioning of MSCs with the artificial transfer of cardiac mitochondria appears to be promising strategy to improve the efficacy of MSC-based cell therapy in ischemic heart disease.

Better isolation, proliferation and differentiation of human adipose-derived mesenchymal stem cells using human serum

Mesenchymal stem cells have many applications in medicine. Attention to the proliferation and differentiation of stem cell differentiation is an important issue. The aim of this study was to investigate the possibility of optimal isolation, proliferation, and differentiation of adipose tissue-derived mesenchymal stem cells (ADSCs) using human serum. Human serum (HS) was obtained from the venous blood of eight healthy individuals. The rate of proliferation and differentiation of ADSCs and expression of surface markers was assessed by flow cytometry. Bone differentiation was assessed using Alizarin Red staining. Data were analyzed using statistical software. Over time, HS showed more proliferation than fetal bovine serum (FBS) -enriched cells (p <0.05). Differentiation of ADSCs cells ls in HS-enriched medium is faster and more pronounced than differentiation in the control group. The expression of surface markers in the medium containing HS was the same as the medium containing FBS where the expression levels of CD105 and CD95 were found to be positive and the expression of CD34 and CD45 was negative. Due to the better proliferation of adipose tissue-derived mesenchymal cells in the medium containing HS than FBS, it is suggested that human serum be used in future clinical studies. Also, HS is healthier, safer, more accessible, and more affordable than FBS.

Notch Signaling-Modified Mesenchymal Stem Cell Patch Improves Left Ventricular Function via Arteriogenesis Induction in a Rat Myocardial Infarction Model

For ischemic cardiomyopathy (ICM) with limited therapeutic options, the induction of arteriogenesis has the potential to improve cardiac function through major restoration of blood flow. We hypothesized that transplantation of a Notch signaling-modified mesenchymal stem cell (SB623 cell) patch would induce angiogenesis and arteriogenesis in ischemic lesions, leading to improvement of left ventricular (LV) function in a rat ICM model. Two weeks after the induction of ischemia, SB623 cell patch transplantation into ICM rats (SB group, n = 10) or a sham operation (no-treatment group, n = 10) was performed. The LV ejection fraction was significantly improved at 6 weeks after SB623 cell patch transplantation (P < 0.001). Histological findings revealed that the number of von Willebrand factor (vWF)-positive capillary vessels (P < 0.01) and alpha smooth muscle actin (αSMA)- and vWF-positive arterioles with a diameter greater than 20 µm (P = 0.002) was significantly increased in the SB group, suggesting the induction of angiogenesis and arteriogenesis. Moreover, rat cardiomyocytes treated with SB623 cell patch transplantation showed upregulation of ephrin-B2 (P = 0.03) and EphB4 (P = 0.01) gene expression, indicating arteriogenesis induction. In conclusion, SB623 cell patch transplantation improved LV function by inducing angiogenesis and arteriogenesis in a rat ICM model.

Combination of mesenchymal stem cells and three-dimensional collagen scaffold preserves ventricular remodeling in rat myocardial infarction model

BACKGROUND

Cardiovascular diseases are the major cause of mortality worldwide. Regeneration of the damaged myocardium remains a challenge due to mechanical constraints and limited healing ability of the adult heart tissue. Cardiac tissue engineering using biomaterial scaffolds combined with stem cells and bioactive molecules could be a highly promising approach for cardiac repair. Use of biomaterials can provide suitable microenvironment to the cells and can solve cell engraftment problems associated with cell transplantation alone. Mesenchymal stem cells (MSCs) are potential candidates in cardiac tissue engineering because of their multilineage differentiation potential and ease of isolation. Use of DNA methyl transferase inhibitor, such as zebularine, in combination with three-dimensional (3D) scaffold can promote efficient MSC differentiation into cardiac lineage, as epigenetic modifications play a fundamental role in determining cell fate and lineage specific gene expression.

AIM

To investigate the role of collagen scaffold and zebularine in the differentiation of rat bone marrow (BM)-MSCs and their subsequent in vivo effects.

METHODS

MSCs were isolated from rat BM and characterized morphologically, immunophenotypically and by multilineage differentiation potential. MSCs were seeded in collagen scaffold and treated with 3 μmol/L zebularine in three different ways. Cytotoxicity analysis was done and cardiac differentiation was analyzed at the gene and protein levels. Treated and untreated MSC-seeded scaffolds were transplanted in the rat myocardial infarction (MI) model and cardiac function was assessed by echocardiography. Cell tracking was performed by DiI dye labeling, while regeneration and neovascularization were evaluated by histological and immunohistochemical analysis, respectively.

RESULTS

MSCs were successfully isolated and seeded in collagen scaffold. Cytotoxicity analysis revealed that zebularine was not cytotoxic in any of the treatment groups. Cardiac differentiation analysis showed more pronounced results in the type 3 treatment group which was subsequently chosen for the transplantation in the in vivo MI model. Significant improvement in cardiac function was observed in the zebularine treated MSC-seeded scaffold group as compared to the MI control. Histological analysis also showed reduction in fibrotic scar, improvement in left ventricular wall thickness and preservation of ventricular remodeling in the zebularine treated MSC-seeded scaffold group. Immunohistochemical analysis revealed significant expression of cardiac proteins in DiI labeled transplanted cells and a significant increase in the number of blood vessels in the zebularine treated MSC-seeded collagen scaffold transplanted group.

CONCLUSION

Combination of 3D collagen scaffold and zebularine treatment enhances cardiac differentiation potential of MSCs, improves cell engraftment at the infarcted region, reduces infarct size and improves cardiac function.

Revascularization of chronic total occlusion coronary artery and cardiac regeneration

Coronary chronic total occlusion (CTO) contributes to the progression of heart failure in patients with ischemic cardiomyopathy. Randomized controlled trials demonstrated that percutaneous coronary intervention (PCI) for CTO significantly improves angina symptoms and quality of life but fails to reduce clinical events compared with optimal medical therapy. Even so, intervening physicians strongly support CTO-PCI. Cardiac regeneration therapy after CTO-PCI should be a promising approach to improving the prognosis of ischemic cardiomyopathy. However, the relationship between CTO revascularization and cardiac regeneration has rarely been studied, and experimental studies on cardiac regeneration usually employ rodent models with permanent ligation of the coronary artery rather than reopening of the occlusive artery. Limited early-stage clinical trials demonstrated that cell therapy for cardiac regeneration in ischemic cardiomyopathy reduces scar size, reverses cardiac remodeling, and promotes angiogenesis. This review focuses on the status quo of CTO-PCI in ischemic cardiomyopathy and the clinical prospect of cardiac regeneration in this setting.

Nano-Messengers of the Heart: Promising Theranostic Candidates for Cardiovascular Maladies

Till date, cardiovascular diseases remain a leading cause of morbidity and mortality across the globe. Several commonly used treatment methods are unable to offer safety from future complications and longevity to the patients. Therefore, better and more effective treatment measures are needed. A potential cutting-edge technology comprises stem cell-derived exosomes. These nanobodies secreted by cells are intended to transfer molecular cargo to other cells for the establishment of intercellular communication and homeostasis. They carry DNA, RNA, lipids, and proteins; many of these molecules are of diagnostic and therapeutic potential. Several stem cell exosomal derivatives have been found to mimic the cardioprotective attributes of their parent stem cells, thus holding the potential to act analogous to stem cell therapies. Their translational value remains high as they have minimal immunogenicity, toxicity, and teratogenicity. The current review highlights the potential of various stem cell exosomes in cardiac repair, emphasizing the recent advancements made in the development of cell-free therapeutics, particularly as biomarkers and as carriers of therapeutic molecules. With the use of genetic engineering and biomimetics, the field of exosome research for heart treatment is expected to solve various theranostic requirements in the field paving its way to the clinics.

Pre-Conditioning Methods and Novel Approaches with Mesenchymal Stem Cells Therapy in Cardiovascular Disease

Transplantation of mesenchymal stem cells (MSCs) in the setting of cardiovascular disease, such as heart failure, cardiomyopathy and ischemic heart disease, has been associated with good clinical outcomes in several trials. A reduction in left ventricular remodeling, myocardial fibrosis and scar size, an improvement in endothelial dysfunction and prolonged cardiomyocytes survival were reported. The regenerative capacity, in addition to the pro-angiogenic, anti-apoptotic and anti-inflammatory effects represent the main target properties of these cells. Herein, we review the different preconditioning methods of MSCs (hypoxia, chemical and pharmacological agents) and the novel approaches (genetically modified MSCs, MSC-derived exosomes and engineered cardiac patches) suggested to optimize the efficacy of MSC therapy.

The Influence of Empathy and Consumer Forgiveness on the Service Recovery Effect of Online Shopping

The service failure of online shopping has always plagued online stores, but the current academic circles still need to explore the service recovery of online shopping from the perspective of empathy and consumer forgiveness. Based on the service failure cases of real online shopping, this article uses the method of situational experiment to carry out empirical research, discusses the impact mechanism of service recovery effect from the perspective of empathy and consumer forgiveness, and tests the moderating role of online store reputation. The results show that in the online shopping service recovery scenario, empathy has a positive impact on consumer forgiveness, consumer forgiveness has a positive impact on consumer repurchase intention, and consumer forgiveness plays a mediating effect between empathy and consumer repurchase intention. Online store reputation plays a moderating role in the relationship between consumer forgiveness and consumer repurchase intention. The research conclusion of this article will help to expand the application of empathy and consumer forgiveness in the research of service recovery, enrich the theory of online shopping service recovery, improve the effect of online shopping service recovery, and promote the healthy development of online shopping business models.

Mesenchymal Stem Cell-Derived Extracellular Vesicles in Liver Immunity and Therapy

Mesenchymal stem cells (MSCs), as the most common cell source for stem cell therapy, play an important role in the modulation of innate and adaptive immune responses and have been widely used in clinical trials to treat autoimmune and inflammatory diseases. Recent experimental and clinical studies have shown that MSC-derived extracellular vesicles (MSC-EVs) can inhibit the activation and proliferation of a variety of proinflammatory cells, such as Th1, Th17 and M1 macrophages, reducing the secretion of proinflammatory cytokines, while promoting the proliferation of anti-inflammatory cells, such as M2 macrophages and Tregs, and increasing the secretion of anti-inflammatory cytokines, thus playing a role in immune regulation and exhibiting immunomodulatory functions. Besides MSC-EVs are more convenient and less immunogenic than MSCs. There is growing interest in the role of MSC-EVs in liver diseases owing to the intrinsic liver tropism of MSC-EVs. In this review, we focus on the immunomodulatory effects of MSC-EVs and summarize the pivotal roles of MSC-EVs as a cell-free therapy in liver diseases, including NAFLD, AIH, acute liver failure, liver fibrosis and hepatic ischemia–reperfusion injury. Moreover, we provide a concise overview of the potential use and limits of MSC-EVs in clinical application.

Integrated Strategies of Diverse Feature Selection Methods Identify Aging-Based Reliable Gene Signatures for Ischemic Cardiomyopathy

Objective: Ischemic cardiomyopathy (ICM) is a major cardiovascular state associated with prominently increased morbidity and mortality. Our purpose was to detect reliable gene signatures for ICM through integrated feature selection strategies.

Methods: Transcriptome profiles of ICM were curated from the GEO project. Classification models, including least absolute shrinkage and selection operator (LASSO), support vector machine (SVM), and random forest, were adopted for identifying candidate ICM-specific genes for ICM. Immune cell infiltrates were estimated using the CIBERSORT method. Expressions of candidate genes were verified in ICM and healthy myocardial tissues via Western blotting. JC-1 staining, flow cytometry, and TUNEL staining were presented in hypoxia/reoxygenation (H/R)-stimulated H9C2 cells with TRMT5 deficiency.

Results: Following the integration of three feature selection methods, we identified seven candidate ICM-specific genes including ASPN, TRMT5, LUM, FCN3, CNN1, PCNT, and HOPX. ROC curves confirmed the excellent diagnostic efficacy of this combination of previous candidate genes in ICM. Most of them presented prominent interactions with immune cell infiltrates. Their deregulations were confirmed in ICM than healthy myocardial tissues. TRMT5 expressions were remarkedly upregulated in H/R-stimulated H9C2 cells. TRMT5 deficiency enhanced mitochondrial membrane potential and reduced apoptosis in H/R-exposed H9C2 cells.

Conclusion: Collectively, our findings identified reliable gene signatures through combination strategies of diverse feature selection methods, which facilitated the early detection of ICM and revealed the underlying mechanisms.

Co-transplantation of Mesenchymal Stromal Cells and Induced Pluripotent Stem Cell-Derived Cardiomyocytes Improves Cardiac Function After Myocardial Damage

Induced pluripotent stem cell-derived cardiomyocytes (iPS-CMs) represent an attractive resource for cardiac regeneration. However, survival and functional integration of transplanted iPS-CM is poor and remains a major challenge for the development of effective therapies. We hypothesized that paracrine effects of co-transplanted mesenchymal stromal cells (MSCs) augment the retention and therapeutic efficacy of iPS-CM in a mouse model of myocardial infarction (MI). To test this, either iPS-CM, MSC, or both cell types were transplanted into the cryoinfarction border zone of syngeneic mice immediately after injury. Bioluminescence imaging (BLI) of iPS-CM did not confirm enhanced retention by co-application of MSC during the 28-day follow-up period. However, histological analyses of hearts 28 days after cell transplantation showed that MSC increased the fraction of animals with detectable iPS-CM by 2-fold. Cardiac MRI analyses showed that from day 14 after transplantation on, the animals that have received cells had a significantly higher left ventricular ejection fraction (LVEF) compared to the placebo group. There was no statistically significant difference in LVEF between animals transplanted only with iPS-CM or only with MSC. However, combined iPS-CM and MSC transplantation resulted in higher LVEF compared to transplantation of single-cell populations during the whole observation period. Histological analyses revealed that MSC increased the capillarization in the myocardium when transplanted alone or with iPS-CM and decreased the infarct scar area only when transplanted in combination with iPS-CM. These results indicate that co-transplantation of iPS-CM and MSC improves cardiac regeneration after cardiac damage, demonstrating the potential of combining multiple cell types for increasing the efficacy of future cardiac cell therapies.

HIF-1α overexpression in mesenchymal stem cell-derived exosome-encapsulated arginine-glycine-aspartate (RGD) hydrogels boost therapeutic efficacy of cardiac repair after myocardial infarction

Aims

Naturally secreted extracellular vesicles (EVs) play important roles in stem-mediated cardioprotection. This study aimed to investigate the cardioprotective function and underlying mechanisms of EVs derived from HIF-1α engineered mesenchymal stem cells (MSCs) in a rat model of AMI.

Methods and results

EVs isolated from HIF-1α engineered MSCs (HIF-1α-EVs) and control MSCs (NC-EVs) were prepared. In in vitro experiments, the EVs were incubated with cardiomyocytes and endothelial cells exposed to hypoxia and serum deprivation (H/SD); in in vivo experiments, the EVs were injected in the acutely infarcted hearts of Sprague-Dawley rats. Compared with NC-EVs, HIF-1α-EVs significantly inhibited the apoptosis of cardiomyocytes and enhanced angiogenesis of endothelial cells; meanwhile, HIF-1α-EVs also significantly shrunk fibrotic area and strengthened cardiac function in infarcted rats. After treatment with EVs/RGD-biotin hydrogels, we observed longer retention, higher stability in HIF-1α-EVs, and stronger cardiac function in the rats. Quantitative real-time PCR (qRT-PCR) displayed that miRNA-221-3p was highly expressed in HIF-1α-EVs. After miR-221-3p was inhibited in HIF-1α-EVs, the biological effects of HIF-1α EVs on apoptosis and angiogenesis were attenuated.

Conclusion

EVs released by MSCs with HIF-1α overexpression can promote the angiogenesis of endothelial cells and the apoptosis of cardiomyocytes via upregulating the expression of miR-221-3p. RGD hydrogels can enhance the therapeutic efficacy of HIF-1α engineered MSCs-derived EVs.

Allogeneic vs. autologous mesenchymal stem/stromal cells in their medication practice

Mesenchymal stem/stromal cell (MSC)-based therapeutics is already available for treatment of a range of diseases or medical conditions. Autologous or allogeneic MSCs obtained from self or donors have their own advantages and disadvantages in their medical practice. Therapeutic benefits of using autologous vs. allogeneic MSCs are inconclusive. Transplanted MSCs within the body interact with their physical microenvironment or niche, physiologically or pathologically, and such cells in a newly established tissue microenvironment may be impacted by the pathological harmful environmental factors to alter their unique biological behaviors. Meanwhile, a temporary microenvironment/niche may be also altered by the resident or niche-surrounding MSCs. Therefore, the functional plasticity and heterogeneity of MSCs caused by different donors and subpopulations of MSCs may result in potential uncertainty in their safe and efficacious medical practice. Acknowledging a connection between MSCs' biology and their existing microenvironment, donor-controlled clinical practice for the long-term therapeutic benefit is suggested to further consider minimizing MSCs potential harm for MSC-based individual therapies. In this review, we summarize the advantages and disadvantages of autologous vs. allogeneic MSCs in their therapeutic applications. Among other issues, we highlight the importance of better understanding of the various microenvironments that may affect the properties of niche-surrounding MSCs and discuss the clinical applications of MSCs within different contexts for treatment of different diseases including cardiomyopathy, lupus and lupus nephritis, diabetes and diabetic complications, bone and cartilage repair, cancer and tissue fibrosis.

Mass Customized Outlook for Regenerative Heart Failure Care

Heart failure pathobiology is permissive to reparative intent. Regenerative therapies exemplify an emerging disruptive innovation aimed at achieving structural and functional organ restitution. However, mixed outcomes, complexity in use, and unsustainable cost have curtailed broader adoption, mandating the development of novel cardio-regenerative approaches. Lineage guidance offers a standardized path to customize stem cell fitness for therapy. A case in point is the molecular induction of the cardiopoiesis program in adult stem cells to yield cardiopoietic cell derivatives designed for heart failure treatment. Tested in early and advanced clinical trials in patients with ischemic heart failure, clinical grade cardiopoietic cells were safe and revealed therapeutic improvement within a window of treatment intensity and pre-treatment disease severity. With the prospect of mass customization, cardiopoietic guidance has been streamlined from the demanding, recombinant protein cocktail-based to a protein-free, messenger RNA-based single gene protocol to engineer affordable cardiac repair competent cells. Clinical trial biobanked stem cells enabled a systems biology deconvolution of the cardiopoietic cell secretome linked to therapeutic benefit, exposing a paracrine mode of action. Collectively, this new knowledge informs next generation regenerative therapeutics manufactured as engineered cellular or secretome mimicking cell-free platforms. Launching biotherapeutics tailored for optimal outcome and offered at mass production cost would contribute to advancing equitable regenerative care that addresses population health needs.

Preclinical Evaluation of the Safety and Immunological Action of Allogeneic ADSC-Collagen Scaffolds in the Treatment of Chronic Ischemic Cardiomyopathy

The use of allogeneic adipose-derived mesenchymal stromal cells (alloADSCs) represents an attractive approach for treating myocardial infarction (MI). Furthermore, adding a natural support improves alloADSCs engraftment and survival in heart tissues, leading to a greater therapeutic effect. We aimed to examine the safety and immunological reaction induced by epicardial implantation of a clinical-grade collagen scaffold (CS) seeded with alloADSCs for its future application in humans. Thus, cellularized scaffolds were myocardially or subcutaneously implanted in immunosuppressed rodent models. The toxicological parameters were not significantly altered, and tumor formation was not found over the short or long term. Furthermore, biodistribution analyses in the infarcted immunocompetent rats displayed cell engraftment in the myocardium but no migration to other organs. The immunogenicity of alloADSC-CS was also evaluated in a preclinical porcine model of chronic MI; no significant humoral or cellular alloreactive responses were found. Moreover, CS cellularized with human ADSCs cocultured with human allogeneic immune cells produced no alloreactive response. Interestingly, alloADSC-CS significantly inhibited lymphocyte responses, confirming its immunomodulatory action. Thus, alloADSC-CS is likely safe and does not elicit any alloreactive immunological response in the host. Moreover, it exerts an immunomodulatory action, which supports its translation to a clinical setting.

Comparison between Intra-Articular Injection of Infrapatellar Fat Pad (IPFP) Cell Concentrates and IPFP-Mesenchymal Stem Cells (MSCs) for Cartilage Defect Repair of the Knee Joint in Rabbits

Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic method in regenerative medicine. Our previous research adopted a simple nonenzymatic strategy for the preparation of a new type of ready-to-use infrapatellar fat pad (IPFP) cell concentrates. The aim of this study was to compare the therapeutic efficacy of intra-articular (IA) injection of autologous IPFP cell concentrates and allogeneic IPFP-MSCs obtained from these concentrates in a rabbit articular cartilage defect model. IPFP-MSCs sprouting from the IPFP cell concentrates were characterized via flow cytometry as well as based on their potential for differentiation into adipocytes, osteoblasts, and chondrocytes. In the rabbit model, cartilage defects were created on the trochlear groove, followed by treatment with IPFP cell concentrates, IPFP-MSCs, or normal saline IA injection. Distal femur samples were evaluated at 6 and 12 weeks posttreatment via macroscopic observation and histological assessment based on the International Cartilage Repair Society (ICRS) macroscopic scoring system as well as the ICRS visual histological assessment scale. The macroscopic score and histological score were significantly higher in the IPFP-MSC group compared to the IPFP cell concentrate group at 12 weeks. Further, both treatment groups had higher scores compared to the normal saline group. In comparison to the latter, the groups treated with IPFP-MSCs and IPFP cell concentrates showed considerably better cartilage regeneration. Overall, IPFP-MSCs represent an effective therapeutic strategy for stimulating articular cartilage regeneration. Further, due to the simple, cost-effective, nonenzymatic, and safe preparation process, IPFP cell concentrates may represent an effective alternative to stem cell-based therapy in the clinic.