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Ischemic heart disease is among the primary causes of cardiovascular-related deaths worldwide. Conventional treatments including surgical interventions and medical therapies aid in preventing further damage to heart muscle but are unable to provide a permanent solution. In recent years, stem cell therapy has emerged as an attractive alternative to restore damaged myocardium after myocardial injury. Allogeneic (donor-derived) mesenchymal stem cells (MSCs) have shown great promise in preclinical and clinical studies, making them the most widely accepted candidates for cardiac cell therapy. MSCs promote cardiac repair by modulating host immune system and secreting various soluble factors, of which prostaglandin E2 (PGE2) is an important one. PGE2 plays a significant role in regulating cardiac remodeling following myocardial injury. In this review, we provide an overview of allogeneic MSCs as candidates for myocardial regeneration with a focus on the role of the PGE2/cyclooxygenase-2 (COX2) pathway in mediating these effects. Key words: mesenchymal stem cells, COX2, PGE2, cardiac ischemia, immunoprivilege, cell therapy. La maladie cardiaque ischemique est parmi les principales causes de deces liees au systeme cardiovasculaire a l'echelle mondiale. Les traitements classiques, y compris les interventions chirurgicales et les traitements medicaux, contribuent a la prevention de plus de dommages au muscle cardiaque, mais ne sont pas en mesure de fournir une solution definitive. Au cours des dernieres annees, le traitement par les cellules souches s'est revele constituer un autre choix attrayant pour le retablissement du myocarde endommage a la suite de lesions myocardiques. Les cellules souches mesenchymateuses (CSM) allogeniques (issues de donneurs) se sont revelees tres prometteuses dans les etudes precliniques et cliniques, ce qui en a fait les candidates les plus largement acceptees pour la therapie cellulaire cardiaque. Les CSM favorisent la reparation du creur par l'intermediaire de la modulation du systeme immunitaire de l'hote et la secretion de divers facteurs solubles, dont la PGE2 est l'une des plus importantes. La PGE2 joue un role important dans la regulation du remodelage du creur a la suite de lesions cardiaques. Dans cet article de synthese, nous of frons un aperqu des CSM allogeniques en tant que candidates pour la regenerescence du myocarde, avec une attention particuliere sur le role de la voie de signalisation PGE2/COX2 dans la mediation de ces effets. [Traduit par la Redaction] Mots-cles: cellules souches mesenchymateuses, COX2, PGE2, ischemie cardiaque, immunoprivilege, therapie cellulaire., Introduction Cardiovascular diseases are the leading cause of deaths around the globe, consuming nearly 17.9 million lives annually (World Health Organization 2017). In Canada alone, these deaths account for almost [...]

Increasing reports of successful and safe application of bone marrow derived mesenchymal stem cells (BM-MSCs) for cell therapy are pouring in from numerous studies. However poor survival of transplanted cells in the recipient has impaired the benefits of BM-MSCs based therapies. Therefore cell product preparation procedures pertaining to MSC therapy need to be optimized to improve the survival of transplanted cells. One of the important ex vivo procedures in the preparation of cells for therapy is passaging of BM-MSCs to ensure a suitable number of cells for transplantation, which may affect the turnover of proteins involved in regulation of cell survival and (or) death pathways. In the current study, we investigated the effect of an increase in passage number of BM-MSCs in cell culture on the intracellular protein turnover (protein synthesis, processing, and degradation machinery). We performed proteomic analysis of BM-MSCs at different passages. There was no significant difference observed in the ribosomal, protein processing, and proteasomal pathways related proteins in BM-MSCs with an increase in passage number from P3 to P7. Therefore, expansion of MSCs in the cell culture in clinically relevant passages (Passage 3-7) does not affect the quality of MSCs in terms of intracellular protein synthesis and turnover. Key words: mesenchymal stem cells, transplantation, regenerative therapy, proteomic analysis. De plus en plus de rapports de succes de l'application securitaire de cellules souches mesenchymateuses (CSM) issues de la moelle osseuse a la therapie cellulaire affluent de nombreuses etudes. Cependant, les bienfaits tires des therapies a base de CSM sont voiles par la mauvaise survie des cellules greffees chez le receveur. Par consequent, il convient d'optimiser les procedures de preparation de produits cellulaires afferents a la therapie par les CSM en vue d'ameliorer la survie des cellules greffees. Le repiquage des CSM represente une importante procedure de preparation ex vivo des cellules servant aux traitements dans le but de s'assurer de la presence d'un nombre approprie de cellules pour la greffe. Toutefois, cette procedure peut entrainer des modifications dans le <> des proteines jouant un role dans la regulation des voies de signalisation de la survie ou de la mort cellulaires. Dans les presents travaux, nous avons etudie l'effet de l'augmentation du nombre de repiquages de CSM en culture cellulaire sur le << turnover >>intracellulaire des proteines (rouages de leur synthese, de leur traitement et de leur degradation). Nous avons effectue une analyse proteomique des CSM lors de differents repiquages. Lors de l'augmentation du nombre de cellules repiquees entre P3 et P7, nous n'avons observe aucune difference notable quant aux proteines liees aux voies de signalisation des proteases ainsi que du traitement ribosomal et des proteines dans les CSM. Par consequent, l'expansion des CSM en culture cellulaire par les repiquages cliniquement significatifs (repiquages 3 a 7) n'a pas d'effet qualitatif sur les CSM en matiere de synthese et de <> des proteines intracellulaires. [Traduit par la Redaction] Mots-cles: cellules souches mesenchymateuses, greffe, therapie regeneratrice, analyse proteomique., Introduction Mesenchymal stem cells (MSCs) form 0.01%-0.001% of the stromal population from bone marrow (BM) (Mendez-Ferrer et al. 2010). These cells have the characteristics of being plastic adherent, spindle shaped, [...]

MXene QDs (MQDs) have been effectively used in several fields of biomedical research. Considering the role of hyperactivation of immune system in infectious diseases, especially in COVID‐19, MQDs stand as a potential candidate as a nanotherapeutic against viral infections. However, the efficacy of MQDs against SARS‐CoV‐2 infection has not been tested yet. In this study, Ti3C2 MQDs are synthesized and their potential in mitigating SARS‐CoV‐2 infection is investigated. Physicochemical characterization suggests that MQDs are enriched with abundance of bioactive functional groups such as oxygen, hydrogen, fluorine, and chlorine groups as well as surface titanium oxides. The efficacy of MQDs is tested in VeroE6 cells infected with SARS‐CoV‐2. These data demonstrate that the treatment with MQDs is able to mitigate multiplication of virus particles, only at very low doses such as 0,15 µg mL−1. Furthermore, to understand the mechanisms of MQD‐mediated anti‐COVID properties, global proteomics analysis are performed and determined differentially expressed proteins between MQD‐treated and untreated cells. Data reveal that MQDs interfere with the viral life cycle through different mechanisms including the Ca2+ signaling pathway, IFN‐α response, virus internalization, replication, and translation. These findings suggest that MQDs can be employed to develop future immunoengineering‐based nanotherapeutics strategies against SARS‐CoV‐2 and other viral infections. [ABSTRACT FROM AUTHOR]

Cardiac injury and loss of cardiomyocytes is a causative as well as a resultant condition of cardiovascular disorders, which are the leading cause of death throughout the world. This loss of cardiomyocytes cannot be completely addressed through the currently available drugs being administered, which mainly function only in relieving the symptoms. There is a huge potential being investigated for regenerative and cell replacement therapies through recruiting stem cells of various origins namely embryonic, reprogramming/induction, and adult tissue. These sources are being actively studied for translation to clinical scenarios. In this review, we attempt to discuss some of these promising scenarios, including the clinical trials and the obstacles that need to be overcome, and hope to address the direction in which stem cell therapy is heading. Key words: stem cell therapy, cardiac regeneration, cardiomyocytes, heart failure, reprogramming. Les lesions cardiaques et la perte de cardiomyocytes sont les causes autant que les resultantes des maladies cardiovasculaires, la principale cause de deces a l'echelle mondiale. Les medicaments actuels ne suffisent pas a enrayer cette perte de cardiomyocytes : leurs effets se limitent presque exclusivement a l'attenuation des symptomes. Les traitements de regenerescence et de remplacement des cellules par le recrutement de cellules souches d'origines diverses (embryonnaire, reprogrammation-induction et tissu adulte) sont tres prometteurs et font actuellement l'objet de recherches. Ces sources de cellules souches sont etudiees activement en vue de les faire passer au domaine clinique. Dans le present article de synthese, nous tentons de discuter de certains de ces traitements prometteurs, des essais cliniques a mener et des obstacles a surmonter, et abordons l'orientation que prend l'usage therapeutique des cellules souches. [Traduit par la Redaction] Mots-cles: usage therapeutique des cellules souches, regenerescence cardiaque, cardiomyocytes, insuffisance cardiaque, reprogrammation., Introduction There are scores of pharmacological interventions available to deal with the complexities associated with or leading to myocardial infarction (MI), which is a major affliction globally (Gaziano et al. [...]