Recent Advances in Translational Adipose-Derived Stem Cell Biology

Multipotent mesenchymal stem cells/marrow stromal cells (MSCs), originally discovered in the bone marrow by Alexander Friedenstein as early as 1968 [...]

Immunopathology and Immunosenescence, the Immunological Key Words of Severe COVID-19. Is There a Role for Stem Cell Transplantation?

The outcomes of Coronavirus disease-2019 (COVID-19) vary depending on the age, health status and sex of an individual, ranging from asymptomatic to lethal. From an immunologic viewpoint, the final severe lung damage observed in COVID-19 should be caused by cytokine storm, driven mainly by interleukin-6 and other pro-inflammatory cytokines. However, which immunopathogenic status precedes this “cytokine storm” and why the male older population is more severely affected, are currently unanswered questions. The aging of the immune system, i.e., immunosenescence, closely associated with a low-grade inflammatory status called “inflammageing,” should play a key role. The remodeling of both innate and adaptive immune response observed with aging can partly explain the age gradient in severity and mortality of COVID-19. This review discusses how aging impacts the immune response to the virus, focusing on possible strategies to rejuvenate the immune system with stem cell-based therapies. Indeed, due to immunomodulatory and anti-inflammatory properties, multipotent mesenchymal stem cells (MSCs) are a worth-considering option against COVID-19 adverse outcomes.

Erythropoietin (EPO) as a Key Regulator of Erythropoiesis, Bone Remodeling and Endothelial Transdifferentiation of Multipotent Mesenchymal Stem Cells (MSCs): Implications in Regenerative Medicine

Human erythropoietin (EPO) is an N-linked glycoprotein consisting of 166 aa that is produced in the kidney during the adult life and acts both as a peptide hormone and hematopoietic growth factor (HGF), stimulating bone marrow erythropoiesis. EPO production is activated by hypoxia and is regulated via an oxygen-sensitive feedback loop. EPO acts via its homodimeric erythropoietin receptor (EPO-R) that increases cell survival and drives the terminal erythroid maturation of progenitors BFU-Es and CFU-Es to billions of mature RBCs. This pathway involves the activation of multiple erythroid transcription factors, such as GATA1, FOG1, TAL-1, EKLF and BCL11A, and leads to the overexpression of genes encoding enzymes involved in heme biosynthesis and the production of hemoglobin. The detection of a heterodimeric complex of EPO-R (consisting of one EPO-R chain and the CSF2RB β-chain, CD131) in several tissues (brain, heart, skeletal muscle) explains the EPO pleotropic action as a protection factor for several cells, including the multipotent MSCs as well as cells modulating the innate and adaptive immunity arms. EPO induces the osteogenic and endothelial transdifferentiation of the multipotent MSCs via the activation of EPO-R signaling pathways, leading to bone remodeling, induction of angiogenesis and secretion of a large number of trophic factors (secretome). These diversely unique properties of EPO, taken together with its clinical use to treat anemias associated with chronic renal failure and other blood disorders, make it a valuable biologic agent in regenerative medicine for the treatment/cure of tissue de-regeneration disorders.

The concept of obtaining and using multipotent mesenchymal stem cells in the treatment of dental diseases: literature review

The discovery of stem cells is considered one of the most important achievements of mankind. The ability of any stem cells to produce different cell types makes them a very convenient system for studying the molecular genetic events that cause cell differentiation. Due to their ability to differentiate into any tissue, stem cells can be used to treat a huge number of diseases. Therefore, the comprehensive study of stem cells is one of the most relevant and promising areas of modern medicine.

Dysfunction of the Neurovascular Unit in Ischemic Stroke: Highlights on microRNAs and Exosomes as Potential Biomarkers and Therapy

Ischemic stroke is a damaging cerebral vascular disease associated with high disability and mortality rates worldwide. In spite of the continuous development of new diagnostic and prognostic methods, early detection and outcome prediction are often very difficult. The neurovascular unit (NVU) is a complex multicellular entity linking the interactions between neurons, glial cells, and brain vessels. Novel research has revealed that exosome-mediated transfer of microRNAs plays an important role in cell-to-cell communication and, thus, is integral in the multicellular crosstalk within the NVU. After a stroke, NVU homeostasis is altered, which induces the release of several potential biomarkers into the blood vessels. The addition of biological data representing all constituents of the NVU to clinical and neuroradiological findings can significantly advance stroke evaluation and prognosis. In this review, we present the current literature regarding the possible beneficial roles of exosomes derived from the components of the NVU and multipotent mesenchymal stem cells in preclinical studies of ischemic stroke. We also discuss the most relevant clinical trials on the diagnostic and prognostic roles of exosomes in stroke patients.

APPLICATION OF MULTIPOTENT MESENCHYMAL STEM CELL SECRETOME IN THE TREATMENT OF ADJUVANT ARTHRITIS AND CONTACT-ALLERGIC DERMATITIS IN ANIMAL MODELS

The therapeutic effect of multipotent mesenchymal stem cells has been proven on various disease models. One of the mechanisms is the paracrine effect of the cells on the surrounding tissues.The aim. To investigate the secretome effectiveness of the multipotent mesenchymal stem cells in the treatment of adjuvant arthritis and contact-allergic dermatitis in Wistar rats.Materials and methods. Adjuvant arthritis was simulated in 26 female rats by the administration of Freund's complete adjuvant and then treated with the administration of 100 µl of multipotent mesenchymal stem cell secretome or saline. Contact-allergic dermatitis was modeled on 30 female rats by applying 200 μl of an oil solution of dinitrofluorobenzene to the skin on days 1, 5 and 6. Then the rats were treated with fluocinolone ointment (a positive control), baby cream (a negative control), baby cream with a secretome of native multipotent mesenchymal stem cells or from the cells processed with dexamethasone.Results. Judging by the indicators of the longitudinal and transverse dimensions of the paws in rats and a histological examination, the secretome did not have any anti-inflammatory effect on adjuvant arthritis. A cream with a secret from multipotent mesenchymal stem cells processed with dexamethasone, was the most effective on the model of contact-allergic dermatitis: the clinical improvement occurred on the 2nd day. The secretome from native multipotent mesenchymal stem cells and fluocinolone had a therapeutic effect on the 3rd day of application, the negative control - on the 4th day. The lymphocytic infiltration coefficient was significantly lower (p <0.05) in all the cases compared to the negative control (2.8 ± 0.1). However, the lowest infiltration was observed when the cream with secretome from native (1.75 ± 0,1) and dexamethasone-stimulated (1.76 ± 0.1) multipotent mesenchymal stem cells was being used.Conclusion. The cream with the secretome of multipotent mesenchymal stem cells suppresses lymphocytic infiltration more strongly than the highly active topical glucocorticosteroid - fluocinolone - on the model of contact-allergic dermatitis, which is a classic local delayed-type hypersensitivity reaction. However, a further study of the therapeutic effect of the secretome on models of systemic inflammatory diseases is required after its preliminary purification from large-molecular proteins.

Stem Cell Therapy: A Promising Treatment of Parkinson’s Diseases

The neurodegenerative disorder is a prolonged persistence curse and effect on economic and physical challenges in an aging world. Parkinson has come in the second category of disability disorders and associated with progressive dopaminergic neuronal degeneration with severe motor complications. It is an observation that gradual disease progression causes 70% degeneration of striatal dopaminergic neurons. Globally there are around 7-10 million patients with Parkinson's disease, however, there are huge efforts for therapeutic improvement. According to studies, no single molecular pathway was pointed out as a single etiology to control disease progression due to a lack of targeted therapeutic strategies. Previously implemented symptomatic treatments include L-dopa (L-3,4-dihydroxyphenylalanine), deep brain stimulation, and the surgical insertion of a medical device. This leads to dyskinesia, dystonia and a higher risk of major surgical complications respectively. However, not all the above-mentioned therapies cannot regenerate the dopaminergic neurons in Parkinson’s disease patients. Recent advances in the field of cellular therapy have shown promising outcomes by differentiation of multipotent mesenchymal stem cells into dopaminergic neurons under the influence of a regenerative substance. In this review, we have discussed the differentiation of dopaminergic neurons by using different cell types that can be used as a cellular therapeutic approach for Parkinson’s disease. The information was collected through a comprehensive search using the keywords, “Parkinson Disease, Dopamine, Brain derived neurotrophic factor and neuron from reliable search engines, PubMed, Google Scholar and Medline reviews from the year 2010 to 2020.

Autogous cell using for the restoration of functional defects in patients with ischemic cerebrovascular accident

Stroke is a global medical and socio-economic problem and a great demand for alternative therapies, the leading one being stem cell (SC) therapy. Pathogenetic processes in ischemic stroke (II) trigger the mechanisms of necrotic and apoptotic death of neurons with the formation of the central infarct zone («core of ischemia») and the ischemic «penumbra» zone; the severity and reversibility of the injury directly depends on the duration of ischemia. In parallel with pathogenetic processes, endogenous neurogenesis occurs – the proliferation of neurogenic stem and progenitor cells (NSC/NPC) and their migration into the ischemic focus; however, most NSCs and newly formed neurons undergo apoptosis and recovery of lost functions does not occur. Significant efforts are being made to find ways to control neurogenesis, in particular through the transplantation of exogenous SCs. The main factors preventing the use of SCs in humans are moral, ethical, religious and legal aspects related to the source and method of obtaining cells, as well as possible immunocompromised complications due to incompatibility of donor cells with the recipient of the main histocompatibility complex antigens. The safest is the use of autologous SCs (the patient’s own cells), as it does not require the use of immunosuppressive protocols. Due to the relative safety and ease of production, the most common are multipotent mesenchymal stem cells (MSCs), namely MSCs of the bone marrow (BM). Numerous preclinical studies in experimental animals with modeled II, as well as clinical trials conducted over the past 15 years, have shown the safety and feasibility of transplantation of autologous MSCs in patients with severe neurological deficits after II. Two different approaches to the use of MSCs are discussed: neuroprotection in the acute phase and neurorestoration in the chronic phase II. Proposals are currently being developed for phase II/III clinical trials in acute and chronic stroke using BM MSCs, the results of which will form the basis for certified standardized II treatment protocols.

Geometrical Structure of Honeycomb TCP to Control Dental Pulp-Derived Cell Differentiation

Recently, dental pulp has been attracting attention as a promising source of multipotent mesenchymal stem cells (MSCs) for various clinical applications of regeneration fields. To date, we have succeeded in establishing rat dental pulp-derived cells showing the characteristics of odontoblasts under in vitro conditions. We named them Tooth matrix-forming, GFP rat-derived Cells (TGC). However, though TGC form massive dentin-like hard tissues under in vivo conditions, this does not lead to the induction of polar odontoblasts. Focusing on the importance of the geometrical structure of an artificial biomaterial to induce cell differentiation and hard tissue formation, we previously have succeeded in developing a new biomaterial, honeycomb tricalcium phosphate (TCP) scaffold with through-holes of various diameters. In this study, to induce polar odontoblasts, TGC were induced to form odontoblasts using honeycomb TCP that had various hole diameters (75, 300, and 500 μm) as a scaffold. The results showed that honeycomb TCP with 300-μm hole diameters (300TCP) differentiated TGC into polar odontoblasts that were DSP positive. Therefore, our study indicates that 300TCP is an appropriate artificial biomaterial for dentin regeneration.