Selective Accumulation of Poly(Lactic-Co-Glycolic Acid) Nanoparticles in Endotheliocytes and Mesenchymal Stromal Cells Cultured as Mixed-Cell Spheroids

The use of drug-loaded nanoparticles is an actively developed approach in targeted cancer therapy. Prevascularized spheroids generated from mesenchymal stem cells and endotheliocytes are considered as a model to evaluate the tropism of therapeutic nanoparticles to a specific tissue. Nanoparticles based on co-polymer of lactic and glycolic acids (poly(lactic-co-glycolic acid; PLGA) labeled with cyanine dye (Cy5) were incubated with prevascularized spheroids, and the rate of their penetration and their distribution in the spheroid-forming cells were evaluated. Endotheliocytes more intensively accumulated nanoparticles than mesenchymal stem cells: the number of nanoparticles in mixed-cell spheroids of mesenchymal stem cells and endotheliocytes was greater than in spheroids built solely of mesenchymal stem cells by 5±1.2 times. The developed 3D in vitro cell model provides a low-cost way to assess tissue tropism of therapeutic nanoparticles under conditions closer to natural in comparison with 2D culture.

Hepatic Macrophages as Targets for the MSC-Based Cell Therapy in Non-Alcoholic Steatohepatitis

Non-alcoholic steatohepatitis (NASH) is a serious public health issue associated with the obesity pandemic. Obesity is the main risk factor for the non-alcoholic fatty liver disease (NAFLD), which progresses to NASH and then to end-stage liver disease. Currently, there are no specific pharmacotherapies of NAFLD/NASH approved by the FDA or other national regulatory bodies and the treatment includes lifestyle adjustment and medicines for improving lipid metabolism, enhancing sensitivity to insulin, balancing oxidation, and counteracting fibrosis. Accordingly, further basic research and development of new therapeutic approaches are greatly needed. Mesenchymal stem cells (MSCs) and MSC-derived extracellular vesicles prevent induced hepatocyte death in vitro and attenuate NASH symptoms in animal models of the disease. They interact with hepatocytes directly, but also target other liver cells, including Kupffer cells and macrophages recruited from the blood flow. This review provides an update on the pathogenesis of NAFLD/NASH and the key role of macrophages in the development of the disease. We examine in detail the mechanisms of the cross-talk between the MSCs and the macrophages, which are likely to be among the key targets of MSCs and their derivatives in the course of NAFLD/NASH cell therapy.

The Crosstalk between Mesenchymal Stromal/Stem Cells and Hepatocytes in Homeostasis and under Stress

Liver diseases, characterized by high morbidity and mortality, represent a substantial medical problem globally. The current therapeutic approaches are mainly aimed at reducing symptoms and slowing down the progression of the diseases. Organ transplantation remains the only effective treatment method in cases of severe liver pathology. In this regard, the development of new effective approaches aimed at stimulating liver regeneration, both by activation of the organ's own resources or by different therapeutic agents that trigger regeneration, does not cease to be relevant. To date, many systematic reviews and meta-analyses have been published confirming the effectiveness of mesenchymal stromal cell (MSC) transplantation in the treatment of liver diseases of various severities and etiologies. However, despite the successful use of MSCs in clinical practice and the promising therapeutic results in animal models of liver diseases, the mechanisms of their protective and regenerative action remain poorly understood. Specifically, data about the molecular agents produced by these cells and mediating their therapeutic action are fragmentary and often contradictory. Since MSCs or MSC-like cells are found in all tissues and organs, it is likely that many key intercellular interactions within the tissue niches are dependent on MSCs. In this context, it is essential to understand the mechanisms underlying communication between MSCs and differentiated parenchymal cells of each particular tissue. This is important both from the perspective of basic science and for the development of therapeutic approaches involving the modulation of the activity of resident MSCs. With regard to the liver, the research is concentrated on the intercommunication between MSCs and hepatocytes under normal conditions and during the development of the pathological process. The goals of this review were to identify the key factors mediating the crosstalk between MSCs and hepatocytes and determine the possible mechanisms of interaction of the two cell types under normal and stressful conditions. The analysis of the hepatocyte-MSC interaction showed that MSCs carry out chaperone-like functions, including the synthesis of the supportive extracellular matrix proteins; prevention of apoptosis, pyroptosis, and ferroptosis; support of regeneration; elimination of lipotoxicity and ER stress; promotion of antioxidant effects; and donation of mitochondria. The underlying mechanisms suggest very close interdependence, including even direct cytoplasm and organelle exchange.

Suppressive Effect of Chemically Induced Hypoxia on Glioblastoma Cell Proliferation

Glioblastoma is a tumor characterized by pronounced hypoxia. Hypoxia produces diverse effects on tumor cells, and the results of experimental studies available so far are contradictory. In vitro hypoxia can be modeled in two ways: by reducing the level of atmospheric oxygen (physically induced hypoxia) or by using hypoxia-inducing chemicals such as cobalt chloride (II) (CoCl2) (chemically induced hypoxia). In the present work, we analyzed the effect of CoCl2 on the viability, proliferation, and apoptosis of cells of three glioblastoma cell lines: 1321N1, T98g, and U373 MG. It was shown that CoCl2 induced a dose-dependent decrease in cell viability and proliferation, and at high concentrations (200 and 400 μM) stimulated cell death. CoCl2 had no effect on the cytotoxic activity of doxorubicin in two cell lines T98g and U373 MG, and enhanced the effect of the chemotherapeutic agent on the 1321N1 cell line, though no synergistic cytotoxic effect of the two agents was observed.

Therapeutic Efficacy and Migration of Mesenchymal Stem Cells after Intracerebral Transplantation in Rats with Experimental Ischemic Stroke

We studied therapeutic efficacy and migration characteristics of mesenchymal stem cells isolated from the human placenta after their intracerebral (stereotactic) administration to rats with the experimental ischemic stroke. It was shown that cell therapy significantly improved animal survival rate and reduced the severity of neurological deficit. New data on the migration pathways of transplanted cells in the brain were obtained.

Isolation of a Population of Cells Co-Expressing Markers of Embryonic Stem Cells and Mesenchymal Stem Cells from the Rudimentary Uterine Horn of a Patient with Uterine Aplasia

More than 50% cells isolated from the endometrial cavity scraping and the myometrium of the rudimentary horn of an underdeveloped uterus removed from a patient with uterine aplasia and maintained under culturing conditions normal for mesenchymal stem cells (MSC) expressed embryonic transcription factors Oct4 and Nanog, embryonic cell membrane sialyl glycolipid SSEA4, and MSC markers. After 2-3 passages, the cells lost the expression of the early embryogenesis markers, but retained MSC markers. The presence of dormant stem cells in the underdeveloped endometrium and in the uterus indicates that this tissue has a regenerative potential that can be activated and used for completion of organ morphogenesis. This task requires the development of methods of early diagnosis of morphogenesis impairment and tools for safe reactivation of the ontogenesis.

Colorectal Cancer and Tumor Stromal Cells Have Different Effects on the Differentiation and Maturation of Dendritic Cells In Vitro

We compared the ability of SW837, SW480, HT-29, Caco-2, and HCT116 colorectal cancer lines and cancer-associated fibroblasts obtained from a colorectal adenocarcinoma biopsy specimen to modulate differentiation and maturation of dendritic cells in co-culture. The expression of surface markers of dendritic cell differentiation (CD1a) and maturation (CD83), as well as the expression of CD14 monocyte marker was evaluated by flow cytometry. Cancer-associated fibroblasts completely suppressed dendritic cell differentiation from peripheral blood monocytes induced by granulocyte-macrophage CSF and IL-4, but had no significant effect on their maturation under the influence of bacterial LPS. On the contrary, tumor cell lines did not interfere with monocyte differentiation, although some of them significantly reduced the level of CD1a expression. In contrast to cancer-associated fibroblasts, tumor cell lines and conditioned medium from primary tumor cell culture suppressed LPS-induced maturation of dendritic cells. These results suggest that tumor cells and cancer-associated fibroblasts can modulate different stages of the antitumor immune response.

Telomeres and Telomerase in the Control of Stem Cells

Stem cells serve as a source of cellular material in embryogenesis and postnatal growth and regeneration. This requires significant proliferative potential ensured by sufficient telomere length. Telomere attrition in the stem cells and their niche cells can result in the exhaustion of the regenerative potential of high-turnover organs, causing or contributing to the onset of age-related diseases. In this review, stem cells are examined in the context of the current telomere-centric theory of cell aging, which assumes that telomere shortening depends not just on the number of cell doublings (mitotic clock) but also on the influence of various internal and external factors. The influence of the telomerase and telomere length on the functional activity of different stem cell types, as well as on their aging and prospects of use in cell therapy applications, is discussed.

Resistance of Human Liver Mesenchymal Stem Cells to FAS-Induced Cell Death

Mesenchymal stem cells (MSCs) have a pronounced therapeutic potential in various pathological conditions. Though therapeutic effects of MSC transplantation have been studied for a long time, the underlying mechanisms are still not clear. It has been shown that transplanted MSCs are rapidly eliminated, presumably by apoptosis. As the mechanisms of MSC apoptosis are not fully understood, in the present work we analyzed MSC sensitivity to Fas-induced apoptosis using MSCs isolated from the biopsies of liver fibrosis patients (L-MSCs). The level of cell death was analyzed by flow cytometry in the propidium iodide test. The luminescent ATP assay was used to measure cellular ATP levels; and the mitochondrial membrane potential was assessed using the potential-dependent dye JC-1. We found that human L-MSCs were resistant to Fas-induced cell death over a wide range of FasL and anti-Fas mAb concentrations. At the same time, intrinsic death signal inducers CoCl₂ and staurosporine caused apoptosis of L-MSCs in a dose-dependent manner. Despite the absence of Fas-induced cell death treatment of L-MSCs with low concentrations of FasL or anti-Fas mAb resulted in a cellular ATP level decrease, while high concentrations of the inducers caused a decline of the mitochondrial membrane potential. Pre-incubation of L-MSCs with the pro-inflammatory cytokine TNF-α did not promote L-MSC cell death. Our data indicate that human L-MSCs have increased resistance to receptor-mediated cell death even under inflammatory conditions.

Heterotypic Multicellular Spheroids as Experimental and Preclinical Models of Sprouting Angiogenesis

Sprouting angiogenesis is the common response of live tissues to physiological and pathological angiogenic stimuli. Its accurate evaluation is of utmost importance for basic research and practical medicine and pharmacology and requires adequate experimental models. A variety of assays for angiogenesis were developed, none of them perfect. In vitro approaches are generally less physiologically relevant due to the omission of essential components regulating the process. However, only in vitro models can be entirely non-xenogeneic. The limitations of the in vitro angiogenesis assays can be partially overcome using 3D models mimicking tissue O2 and nutrient gradients, the influence of the extracellular matrix (ECM), and enabling cell-cell interactions. Here we present a review of the existing models of sprouting angiogenesis that are based on the use of endothelial cells (ECs) co-cultured with perivascular or other stromal cells. This approach provides an excellent in vitro platform for further decoding of the cellular and molecular mechanisms of sprouting angiogenesis under conditions close to the in vivo conditions, as well as for preclinical drug testing and preclinical research in tissue engineering and regenerative medicine.

Analysis of the Correlation between CD133 Expression on Human Colorectal Adenocarcinoma Cells HT-29 and Their Resistance to Chemotherapeutic Drugs

A correlation was found between chemoresistance of HT-29CD133⁺ and HT-29CD133^- sublines obtained after cell sorting and high expression of CD133. On the other hand, knockout of the PROM1 gene and, as a consequence, the absence of CD133 expression did not increase the sensitivity of tumor cells to chemotherapy, which indicates the absence of a direct effect of CD133 on the formation of chemoresistance in colorectal cancer cells. Variants of the HT-29 line with complete or partial knockout of the PROM1 gene were equally sensitive to protein kinase inhibitors sorafenib and sunitinib. Notably, the highest resistance to mTOR inhibitors, temsirolimus and everolimus, was shown by cells with complete knockout of the PROM1 gene (KO-HT-29 (P1)). These findings suggest that CD133 is associated with the chemoresistance of colorectal cancer cells, but is not involved in its formation.

Human Uterine Rudiments: Histological and Immunohistochemical Study

Extensive studies of the rudimental tissues taken from patients with aplasia of the uterus and vagina are aimed at elucidation of the mechanisms of the genesis of these malformations and at the search of the ways of their correction. We performed a histological examination of human uterine rudiments and immunohistochemical analysis of the expression of estrogen and progesterone receptors, VEGF, and stem/progenitor cell markers in these tissues. We found that the rudimental tissues show signs of disorganized histogenesis, but retain activity and contain cells expressing estrogen and progesterone receptors and VEGF as well as poorly differentiated precursor cells or stem cells. The presented data contribute to the in-depth studies of the mechanisms of formation of uterine rudiments and development of methods of their correction.

[Identification of the side population associated with ATP-binding cassette transporters activity using imaging flow cytometry]

DyeCycle Violet efflux, caused by ATP-binding cassette transporters activity, was analyzed in human colorectal adenocarcinoma cell lines SW480, HT-29, Caco-2 by neans of FACSAria III flow cytometer and ImageStreamX Mk II imaging flow cytometer. Along with similarity of cytometry data obtained on the two instruments, the use of imaging flow cytometry made it possible to characterize the morphology of side population cells, as well as morphology of other cell populations differing in the degree of dye accumulation. The population of cells, which are smaller than the side population cells and practically do not take the dye, is of the special interest. Probably, this population may contribute to the tumor resistance to chemotherapy.

Chondrogeneic Potential of MSC from Different Sources in Spheroid Culture

We performed a comparative study of the proliferative potential of human mesenchymal stromal cells (MSC) from three sources (tooth pulp, adipose tissue, and Wharton's jelly) in spheroid culture; human chondroblasts served as the positive control. Histological examination revealed signs of chondrogenic differentiation in all studied cell cultures and the differences in the volume and composition of the extracellular matrix. Spheroids formed by MSC from the tooth pulp and Wharton's jelly were characterized by low content of extracellular matrix and glycosaminoglycans. Spheroids from adipose tissue MSC contained maximum amount of the extracellular matrix and high content of glycosaminoglycans. Chondrocytes produced glycosaminoglycan-enriched matrix. Type II collagen was produced by chondrocytes (to a greater extent) and adipose tissue MSC (to a lesser extent). The results of our study demonstrate that MSC from the adipose tissue under conditions of spheroid culturing exhibited maximum chondrogenic potential.

Intra-Arterial Stem Cell Transplantation in Experimental Stroke in Rats: Real-Time MR Visualization of Transplanted Cells Starting With Their First Pass Through the Brain With Regard to the Therapeutic Action

Cell therapy is an emerging approach to stroke treatment with a potential to limit brain damage and enhance its restoration after the acute phase of the disease. In this study we tested directly reprogrammed neural precursor cells (drNPC) derived from adult human bone marrow cells in the rat middle cerebral artery occlusion (MCAO) model of acute ischemic stroke using human placenta mesenchymal stem cells (pMSC) as a positive control with previously confirmed efficacy. Cells were infused into the ipsilateral (right) internal carotid artery of male Wistar rats 24 h after MCAO. The main goal of this work was to evaluate real-time distribution and subsequent homing of transplanted cells in the brain. This was achieved by performing intra-arterial infusion directly inside the MRI scanner and allowed transplanted cells tracing starting from their first pass through the brain vessels. Immediately after transplantation, cells were observed in the periphery of the infarct zone and in the brain stem, 15 min later small numbers of cells could be discovered deep in the infarct core and in the contralateral hemisphere, where drNPC were seen earlier and in greater numbers than pMSC. Transplanted cells in both groups could no longer be detected in the rat brain 48-72 h after infusion. Histological and histochemical analysis demonstrated that both the drNPC and pMSC were localized inside blood vessels in close contact with the vascular wall. No passage of labeled cells through the blood brain barrier was observed. Additionally, the therapeutic effects of drNPC and pMSC were compared. Both drNPC and pMSC induced substantial attenuation of neurological deficits evaluated at the 7th and 14th day after transplantation using the modified neurological severity score (mNSS). Some of the effects of drNPC and pMSC, such as the influence on the infarct volume and the survival rate of animals, differed. The results suggest a paracrine mechanism of the positive therapeutic effects of IA drNPC and pMSC infusion, potentially enhanced by the cell-cell interactions. Our data also indicate that the long-term homing of transplanted cells in the brain is not necessary for the brain's functional recovery.

Expression of Epithelial Cell Adhesion Molecule (EpCAM) in Tumor Spheroids of Human Colorectal Adenocarcinoma Cells

We studied the formation of spheroids by Caco-2, SW480, and HCT116 human colorectal adenocarcinoma cell lines under low-adhesion culturing conditions. Of these three cell lines, only HCT116 formed stable tumor spheroids. Flow cytometry analysis of 19 surface markers in monolayer HCT116 culture and spheroids formed by these cells revealed considerable similarity of the expression profiles in these two culturing modes. The only exception was EpCAM molecule: its expression in spheroids was 3-fold higher than in the monolayer culture. Scanning confocal laser microscopy showed equal EpCAM distribution in the inner mass of the spheroids.

Proteomic Analysis of Chr 18 Proteins Using 2D Fractionation

One of the main goals of the Chromosome-Centric Human Proteome Project (C-HPP) is detection of "missing proteins" (PE2-PE4). Using the UPS2 (Universal proteomics standard 2) set as a model to simulate the range of protein concentrations in the cell, we have previously shown that 2D fractionation enables the detection of more than 95% of UPS2 proteins in a complex biological mixture. In this study, we propose a novel experimental workflow for protein detection during the analysis of biological samples. This approach is extremely important in the context of the C-HPP and the neXt-MP50 Challenge, which can be solved by increasing the sensitivity and the coverage of the proteome encoded by a particular human chromosome. In this study, we used 2D fractionation for in-depth analysis of the proteins encoded by human chromosome 18 (Chr 18) in the HepG2 cell line. Use of 2D fractionation increased the sensitivity of the SRM SIS method by 1.3-fold (68 and 88 proteins were identified by 1D fractionation and 2D fractionation, respectively) and the shotgun MS/MS method by 2.5-fold (21 and 53 proteins encoded by Chr 18 were detected by 1D fractionation and 2D fractionation, respectively). The results of all experiments indicate that 111 proteins encoded by human Chr 18 have been identified; this list includes 42% of the Chr 18 protein-coding genes and 67% of the Chr 18 transcriptome species (Illumina RNaseq) in the HepG2 cell line obtained using a single sample. Corresponding mRNAs were not registered for 13 of the detected proteins. The combination of 2D fractionation technology with SRM SIS and shotgun mass spectrometric analysis did not achieve full coverage, i.e., identification of at least one protein product for each of the 265 protein-coding genes of the selected chromosome. To further increase the sensitivity of the method, we plan to use 5-10 crude synthetic peptides for each protein to identify the proteins and select one of the peptides based on the obtained mass spectra for the synthesis of an isotopically labeled standard for subsequent quantitative analysis. Data are available via ProteomeXchange with the identifier PXD019263.

Distribution and Migration of Human Placental Mesenchymal Stromal Cells in the Brain of Healthy Rats after Stereotaxic or Intra-Arterial Transplantation

Human placenta mesenchymal stromal cells were injected to healthy rats either stereotaxically into the striatum or intra-arterially through the internal carotid artery. Some cells injected into the brain migrated along the corpus callosum both medially and laterally or concentrated around small blood vessels. A small fraction of MSC injected intra-arterially adhered to the endothelium and stayed inside blood vessels for up to 48 hours mostly in the basin of the middle cerebral artery. Neither stereotaxic, nor intra-arterial transplantation of mesenchymal stromal cells modulated the proliferation of neural stem cells in the subventricular zone of the brain, but stereotaxic transplantation suppressed activation of their proliferation in response to traumatization with the needle.

Methods of Generation of Induced Pluripotent Stem Cells and Their Application for the Therapy of Central Nervous System Diseases

The use of induced pluripotent stem cells (IPSC) is a promising approach to the therapy of CNS diseases. The undeniable advantage of IPSC technology is the possibility of obtaining practically all types of somatic cells for autologous transplantation bypassing bioethical problems. The review presents integrative and non-integrative methods for obtaining IPSC and the ways of their in vitro and in vivo application for the study and treatment of neurological diseases.

[Expression of ganglioside GD2 on colorectal adenocarcinoma cells]

Using flow cytometry GD2 ganglioside expression was evaluated both on colorectal adenocarcinoma cell lines and on tumor tissue samples from colorectal cancer patients. The marker was found on EpCAM-positive tumor cells in 6 of 12 patients' samples but not on the HT29 and CaCo-2 cell lines. GD2 expression was not an exceptional feature of cancer stem cells, since its expression level was similar on CD133-positive and CD133-negative tumor cells. Thus, the presence of GD2 ganglioside was revealed on colorectal adenocarcinoma cells for the first time. This finding makes it possible to use targeted therapy to treat this disease.

[Proteomics of transcription factors: identification of pool of HL-60 cell line-specific regulatory proteins]

HL-60 promyelocytic cells are a widely used as a model for studying induced granulocytic differentiation. Investigation of proteins of the nuclear fraction, particularly transcription factors, is necessary for a better understanding of molecular mechanisms of cell maturation. Mass spectrometry is a powerful tool for analyzing a proteome due to its high sensitivity, specificity and performance. In this paper, using the selected reaction monitoring (SRM) method, we have assessed the levels of RBPJ, STAT1, CEBPB, CASP3, VAV1, PRKDC, PARP1 and UBC9 nuclear proteins isolated using hypertonic buffer, detergents (sodium dodecyl sulfate (SDS), sodium deoxycholate (DOC) and fissionable detergent ProteaseMAX™) and using centrifugation in a sucrose density gradient. The minimum and maximum protein content was 1.13±0.28 and 14.34±1.63 fmol/mkg of total protein for the transcription factor RBPJ and ubiquitin-protein ligase type I UBC9, respectively. According to the results of shotgun mass spectrometric analysis of nuclear fractions, 2356 proteins were identified, of which 106 proteins were annotated as transcription factors. 37 transcription factors were uniquely identified in the fraction obtained by centrifugation in a sucrose density gradient, while only 9 and 8 transcription factors were uniquely identified in the nuclear fractions obtained using hypertonic buffer and detergents, respectively. The transcription factors identified in the HL-60 cell line represent regulatory molecules; their directed profiling under the influence of differentiation inducers, will shed light on the mechanism of granulocyte maturation.

Comparative Analysis of the Effects of Intravenous Administration of Placental Mesenchymal Stromal Cells and Neural Progenitor Cells Derived from Induced Pluripotent Cells on the Course of Acute Ischemic Stroke in Rats

We compared the effects of placental mesenchymal stromal cells and neural progenitor cells derived from induced human pluripotent cells after their intravenous administration to rats in 24 h after transitory occlusion of the middle cerebral artery. The therapeutic effects were evaluated by the dynamics of animal survival, body weight, neurological deficit, and the volume of infarction focus in 7, 14, 30, and 60 days after surgery. Intravenous injection of neural progenitor cells produced a therapeutic effect on the course of experimental ischemic stroke by increasing animal survival in the most acute period and accelerating compensation of neurological deficit and body weight recovery. Neural progenitor cells were more effective than mesenchymal stromal cells from human placenta. The effectiveness of intravenous transplantation of neural progenitor cells in the model of occlusion of the middle cerebral artery is shown by us for the first time, although the therapeutic effect of their direct transplantation into the brain has already been described.

Involvement of Actin Filaments in the Cytotoxic Effect of GD2-Specific Antibodies

Induction of direct cell death is one of the mechanisms of the antitumor effect of GD2-specific antibodies used for the therapy of high-risk neuroblastoma. The mechanisms of the cytotoxic signal triggered by antibody binding to GD2 ganglioside on the surface of the tumor cell remain insufficiently studied. Using inhibitor analysis we demonstrated that actin microfilaments are involved in the cell death induced by GD2-specific antibodies. Specifically, a strong antagonistic influence of cytochalasin D on the cytotoxic effect induced by GD2-specific antibodies was demonstrated in GD2+ tumor cell lines, which was expressed in at least 20% increase in cell survival and a significant decrease of the fraction of cells with fragmented DNA.

[Cell therapy for ischemic stroke. Stem cell types and results of pre-clinical trials]

The literature review addresses the use of stem cells (SC) in ischemic stroke (IS). Part 1 of the paper overviews the results of experimental animal studies. Characteristics of different SC types and results of their studies in experimental models of IS are presented in the first section, the second section considers pros and cons of the methods of SC injection.

MRI Guiding of the Middle Cerebral Artery Occlusion in Rats Aimed to Improve Stroke Modeling

The middle cerebral artery occlusion (MCAO) model in rats closely imitates ischemic stroke and is widely used. Existing instrumental methods provide a certain level of MCAO guidance, but monitoring of the MCA-occluding intraluminal filament position and possible complications can be improved. The goal of this study was to develop a MRI-based method of simultaneous control of the filament position, blood flow in the intracranial vessels, and hemorrhagic complications. Rats were subjected to either MRI-guided MCAO (group 1, n = 51) or MCAO without MRI control (group 2, n = 38). After operation, group 1 rats were transferred into a MRI scanner for the control of the filament position and possible complications. Ninety minutes after the onset of MCAO, the filament was removed in rats of both groups and MRI control of the infarct volume and hemorrhagic complications performed. High-resolution T1- and T2-weighted imaging performed immediately after filament insertion provided visualization of the filament position, blood flow in brain arteries, and complications related to inappropriate filament insertion. It permitted replacement of wrongly positioned filaments and exclusion of animals with complications from the experiment. MRI-based MCAO guiding provided real-time intra-operational monitoring of crucial parameters determining MCAO suitability for stroke modeling, including better assessment of the operation outcomes in individual animals and significant enhancement of the model success rate. The possibility of simultaneous visualization of the filament, blood flow in the arteries, brain tissue, and hemorrhagic complications is the principal advantage of the proposed method over other instrumental methods of MCAO quality control. Graphical Abstract MRI-guided middle cerebral artery occlusion technique permits intra-operational monitoring via direct non-invasive simultaneous visualization of the filament, blood flow in the arteries, brain tissue, and hemorrhagic complications. It provides better assessment of MCAO outcomes in individual animals and significant enhancement of MCAO success rate.

Proteomic Profiling of HL-60 Cells during ATRA-Induced Differentiation

Acute promyelocytic leukemia, a form of acute myeloid leukemia, is characterized by cell differentiation arrest at the promyelocyte stage. Current therapeutic options include administration of all trans-retinoic acid (ATRA), but this treatment produces many side effects. ATRA is known to induce differentiation of leukemic cells into granulocytes, but the mechanism of this process is poorly studied. We performed comparative proteomic profiling of HL-60 promyelocytic cells at different stages of ATRA-induced differentiation to identify differentially expressed proteins by high-resolution mass spectrometry and relative quantitative analysis without isotope labels. A total of 1162 proteins identified by at least two unique peptides were analyzed, among them 46 and 172 differentially expressed proteins were identified in the nuclear and cytosol fractions, respectively. These differentially expressed proteins can represent candidate targets for combination therapy of acute promyelocytic leukemia.

[Comparative proteomic profiling of nuclear and cytosolic fractions from cell lines of different origin]

Proteomic analysis of the nuclear fraction is of great importance, since many cellular processes are initiated in the nucleus. Refinement and choice of experimental procedures for cell lysate fractionation and parameters for mass spectrometric detection and data processing continue to be of current interest. The mass spectrometry analysis presented here was tested on human cell lines derived from different tissues: HL-60 (peripheral blood); HepG2 (liver); EA.hy926 (vascular endothelium). High reproducibility of results and their consistency with biological properties of the objects under study were demonstrated. The use of cells of different types made it possible to reveal a set of 16 proteins whose LFQ-values allow for the discrimination between proteome fractions regardless of cell origin. Also, a set of 16 proteins is suggested which are associated with individual characteristics of cell lines regardless of cell fraction. These protein panels can serve as parameters to verify the proteomic analysis done was of sufficient quality, in particular as indicators of successful fractionation of cell or tissue lysate.

[Cell therapy for ischemic stroke. Results of clinical trials and perspectives of clinical application in the Russian Federation]

The first part of the review summarized the results of preclinical animal studies using stroke models that demonstrated the efficacy of cell therapy. The second part presents the proposed mechanisms of action of stem cells, optimal therapeutic window for cell transplantation, the results of completed clinical trials on humans in the period from 2010 to 2017, as well as the legal aspects of the use of cell technologies in the Russian Federation.

Neural stem/progenitor cells maintained in vitro under different culture conditions alter differentiation capacity of monocytes to generate dendritic cells

Cell therapy of the nervous system disorders using neural stem/progenitor cells (NSPCs) proved its efficacy in preclinical and pilot clinical studies. The mechanisms of the beneficial effects of NSPCs transplantation include replacement of damaged cells, paracrine activation of the regeneration, and immunomodulation. Detailed assessment of NSPCs-induced immunomodulation can contribute to better control of autoimmune reactions and inflammation in patients with neurodegenerative diseases. Interactions of NSPCs with dendritic cells (DCs), the key players in the induction of the immune system response to antigens are of particular interest. Here, we demonstrate that co-culturing of monocytes with NSPCs obtained and grown utilizing serum-containing medium instead of growth factor-containing serum-free medium, results in total suppression of monocyte differentiation into DCs. The effect is similar to the action of mesenchymal stem cells (MSCs). No significant effect on DCs maturation was observed. Cultures of NSPCs set up and maintained in serum-free medium have no influence on monocyte differentiation and DCs maturation. Therefore, the effects of NSPCs upon DC differentiation from monocytes strongly depend on culture conditions, whereas the molecular marker expression patterns are similar in both types of NSPCs cultures. In broader prospective, it means that cells with almost identical phenotypes can display opposite immunological properties depending upon culture conditions. It should be taken into account when developing NSPCs-based cell products for regenerative medicine.

Isolation of Induced Pluripotent Cells from Stromal Liver Cells of Patients with Alcoholic Cirrhosis

Stromal liver cells obtained from liver biopsy specimens of a patient with alcoholic cirrhosis can proliferate for a long time in culture passing more than 30 passages. In the course of culturing from early to late passages, acceleration of cell proliferation, decrease of the expression of some markers, and loss of hepatogenic differentiation potential were observed. On passage 30, induced pluripotent stem cells were obtained from these cells and comparative analysis of adipogenic and hepatic differentiation potencies of these cells and original liver stromal cells was performed. Induced pluripotent stem cells differentiated into both directions more efficiently and more rapidly than initial cells. Under conditions of hepatic differentiation, liver stromal cells started to express markers of definitive endoderm, but not markers of immature/mature hepatocytes, whereas induced pluripotent stem cells consistently expressed markers of definitive endoderm, immature/mature hepatocytes.

[The hepatic differentiation of adult and fetal liver stromal cells in vitro]

The liver has a marked capacity for regeneration. In most cases the liver regeneration is determined by hepatocytes. The regenerative capacity of hepatocytes is significantly reduced in acute or chronic damage. In particular, repair mechanisms are not activated in patients with alcoholic cirrhosis. Organ transplantation or advanced methods of regenerative medicine can help such patients. The promising results were obtained in clinical trials involving patients with various forms of liver disease who received transplantation of autologous bone marrow stem cells. However, to improve the effectiveness of such treatment it is necessary to search for more optimal sources of progenitor cells, as well as to evaluate the possibility of using descendants of these cells differentiated in vitro. In this study we isolated stromal cells from the liver biopsies of three patients with alcoholic cirrhosis, conducted their morphological and phenotypic analysis, and evaluated the hepatic potential of these cells in vitro. The stromal cells isolated from fetal liver were used for comparison. The results of this can serve as a basis for the development of a new method for the treatment of end-stage liver disease. The stromal cells isolated from the liver biopsies for a long time proliferate in a culture and this which makes it possible to expand them to large amounts for subsequent differentiation into hepatocyte-like cells and autologous transplantation.

[Comparison of the expression profile of surface molecular markers on mesenchymal stromal cell cultures isolated from human endometrium and umbilical cord]

Endometrial mesenchymal stromal cells (eMSCs), along with mesenchymal stromal cells (MSCs) isolated from other tissues, are promising for use in regenerative medicine. The benefits of eMSCs include their presence in adults, simplicity of isolation, high proliferative and differentiation capacity. In this study, we have employed the flow cytometry technique to assess expression of 28 molecular markers on the surface of two eMSCs cultures. The culture of MSCs isolated from Wharton's jelly of the umbilical cord (uMSCs) was used as a reference, because uMSCs were studied in details earlier and demonstrated their effectiveness in vivo. Both types of MSCs demonstrated similar expression profiles. They included stem cells surface molecules, cell adhesion molecules and their ligands, some receptor molecules responsible for cell metabolism and proliferation, as well as immunological response molecules.

[Molecular markers of cancer stem cells verified in vivo]

This systematic review aims to analyze molecular markers of cancer stem cells. Only studies that confirmed tumor-initiating capacity of this population by in vivo assay in immunodeficient mice were included. Final sample of papers that fully correspond with initial aim consists of 97 original studies. The results of their analysis reveal that markers commonly used for cancer stem cells deriving were as follows: CD133, СD44, ALDH, CD34, CD24 and EpCAM. The review also contains description of molecular features of some cancer stem cell markers, modern approaches to cancer treatment by targeting this population and brief assessment of cancer stem cell theory development.

Mesenchymal-Epithelial Transition in Culture of Stromal Progenitor Cells Isolated from the Liver of a Patient with Alcoholic Cirrhosis

The cells isolated from biopsy specimen of a patient with alcoholic liver cirrhosis and cultured under standard conditions for obtaining stromal cell culture clearly diverged during early passages into two morphologically and phenotypically different subtypes: epithelial and mesenchymal. Mesenchymal cells expressed CD90 and CD44 and epithelial cells expressed CD166, CD227, and hepatocyte growth factor receptor Met. Starting from passage 6, the culture underwent spontaneous morphological changes and by passages 8-10 contained only epithelium-like cells. CD90 and CD44 expression disappeared, CD166 and CD227 expression remained unchanged, and Met expression increased. A small fraction of cells expressed GATA-4, HNF3β, HNF1α, and HNF4α. After addition of inducers of hepatogeneic differentiation, the cells started producing albumin.

Monitoring of brightness temperature of suspension of follicular thyroid carcinoma cells in SHF range by radiothermometry

THE PURPOSE

The purpose of this research consisted in monitoring of brightness temperature of the suspension of follicular thyroid carcinoma cells during the necrosis of these cells in superhigh frequency (SHF) range.

METHODS

The monitoring of the change in the ratio between brightness temperatures TSHF and TIR values during the necrosis of these cells. The object of study was follicular thyroid carcinoma cells suspension prepared with use of Versene solution and 0.25% trypsin solution. The cells were precipitated by centrifugation and re-suspended in culture medium. The measurements of brightness temperatures were carried out with use of radiothermoimeter. SHF range was 3.4-4.2 GHz, and infrared (IR) range was 8-13 mm. The temperature of the suspension was maintained at 37.5°С.

RESULTS

It was found that upon the necrosis in the suspension of cells, an increase in brightness temperature in 3.4-4.2 GHz range (SHF range) occurs, while brightness temperature of the medium in the IR range does not change.

CONCLUSION

The monitoring of necrosis of follicular thyroid carcinoma cells was carried out by SHF-radiothermometry. It was shown that during the necrosis the change of non-equilibrium state of cell medium occurs, that results in the change in the ratio between TSHF and TIR. During the necrosis, the brightness temperature in SHF range (TSHF) increases.

State of the Art of Chromosome 18-Centric HPP in 2016: Transcriptome and Proteome Profiling of Liver Tissue and HepG2 Cells

A gene-centric approach was applied for a large-scale study of expression products of a single chromosome. Transcriptome profiling of liver tissue and HepG2 cell line was independently performed using two RNA-Seq platforms (SOLiD and Illumina) and also by Droplet Digital PCR (ddPCR) and quantitative RT-PCR. Proteome profiling was performed using shotgun LC-MS/MS as well as selected reaction monitoring with stable isotope-labeled standards (SRM/SIS) for liver tissue and HepG2 cells. On the basis of SRM/SIS measurements, protein copy numbers were estimated for the Chromosome 18 (Chr 18) encoded proteins in the selected types of biological material. These values were compared with expression levels of corresponding mRNA. As a result, we obtained information about 158 and 142 transcripts for HepG2 cell line and liver tissue, respectively. SRM/SIS measurements and shotgun LC-MS/MS allowed us to detect 91 Chr 18-encoded proteins in total, while an intersection between the HepG2 cell line and liver tissue proteomes was ∼66%. In total, there were 16 proteins specifically observed in HepG2 cell line, while 15 proteins were found solely in the liver tissue. Comparison between proteome and transcriptome revealed a poor correlation (R² ≈ 0.1) between corresponding mRNA and protein expression levels. The SRM and shotgun data sets (obtained during 2015-2016) are available in PASSEL (PASS00697) and ProteomeExchange/PRIDE (PXD004407). All measurements were also uploaded into the in-house Chr 18 Knowledgebase at http://kb18.ru/protein/matrix/416126 .

Cell-based therapies of liver diseases: age-related challenges

The scope of this review is to revise recent advances of the cell-based therapies of liver diseases with an emphasis on cell donor's and patient's age. Regenerative medicine with cell-based technologies as its integral part is focused on the structural and functional restoration of tissues impaired by sickness or aging. Unlike drug-based medicine directed primarily at alleviation of symptoms, regenerative medicine offers a more holistic approach to disease and senescence management aimed to achieve restoration of homeostasis. Hepatocyte transplantation and organ engineering are very probable forthcoming options of liver disease treatment in people of different ages and vigorous research and technological innovations in this area are in progress. Accordingly, availability of sufficient amounts of functional human hepatocytes is crucial. Direct isolation of autologous hepatocytes from liver biopsy is problematic due to related discomfort and difficulties with further expansion of cells, particularly those derived from aging people. Allogeneic primary human hepatocytes meeting quality standards are also in short supply. Alternatively, autologous hepatocytes can be produced by reprogramming of differentiated cells through the stage of induced pluripotent stem cells. In addition, fibroblasts and mesenchymal stromal cells can be directly induced to undergo advanced stage hepatogenic differentiation. Reprogramming of cells derived from elderly people is accompanied by the reversal of age-associated changes at the cellular level manifesting itself by telomere elongation and the U-turn of DNA methylation. Cell reprogramming can provide high quality rejuvenated hepatocytes for cell therapy and liver tissue engineering. Further technological advancements and establishment of national and global registries of induced pluripotent stem cell lines homozygous for HLA haplotypes can allow industry-style production of livers for immunosuppression-free transplantation.

CD133+ human colorectal adenocarcinoma cells are resistant to staining with fluorescent dyes used for analysis of ABC transporter activities

Flow cytometry measurement of the expression of surface marker CD133 simultaneously with the analysis of fluorescent dye exclusion was performed in order to develop new methods for detection of cancer stem cell populations in tumor tissue samples from patients with colorectal adenocarcinoma. No correlation was found between the count of CD133(+) cancer cells and the volume of the "population" formed from cells actively pumping off the fluorescent dye. On the other hand, the fluorescence distribution plot showed predominant location of CD133(+) cancer cells among cells stained with neither DyeCycle Violet DNA-binding dye, nor rhodamine 123 mitochondrial dye. These cells did not show the properties of the classical "side population", because they did not shift to the area of stained cell after treatment with ionic channel blocker verapamil.

Neutrophil microparticles modulate cytokine production by natural killer cells

Neutrophil microparticles (NMs) are scarce in the circulation but are highly enriched at sites of inflammation and exert profound effects on immune cells. In the present study, we addressed whether NMs modulate cytokine-producing capacity of natural killer (NK) cells. NMs inhibited the production of IFN-γ and TNF-α but enhanced the release of TGF-β1 by IL-2/IL-12-activated NK cells. The inhibitory effect of NMs was strongly attenuated by blockade of phosphatidylserine exposed on NMs. Thus, NMs skew the cytokine profile of NK cells from pro-inflammatory toward anti-inflammatory, potentially favoring the resolution of inflammation.

Chromosome 18 transcriptoproteome of liver tissue and HepG2 cells and targeted proteome mapping in depleted plasma: update 2013

We report the results obtained in 2012-2013 by the Russian Consortium for the Chromosome-centric Human Proteome Project (C-HPP). The main scope of this work was the transcriptome profiling of genes on human chromosome 18 (Chr 18), as well as their encoded proteome, from three types of biomaterials: liver tissue, the hepatocellular carcinoma-derived cell line HepG2, and blood plasma. The transcriptome profiling for liver tissue was independently performed using two RNaseq platforms (SOLiD and Illumina) and also by droplet digital PCR (ddPCR) and quantitative RT-PCR. The proteome profiling of Chr 18 was accomplished by quantitatively measuring protein copy numbers in the three types of biomaterial (the lowest protein concentration measured was 10(-13) M) using selected reaction monitoring (SRM). In total, protein copy numbers were estimated for 228 master proteins, including quantitative data on 164 proteins in plasma, 171 in the HepG2 cell line, and 186 in liver tissue. Most proteins were present in plasma at 10(8) copies/μL, while the median abundance was 10(4) and 10(5) protein copies per cell in HepG2 cells and liver tissue, respectively. In summary, for liver tissue and HepG2 cells a "transcriptoproteome" was produced that reflects the relationship between transcript and protein copy numbers of the genes on Chr 18. The quantitative data acquired by RNaseq, PCR, and SRM were uploaded into the "Update_2013" data set of our knowledgebase (www.kb18.ru) and investigated for linear correlations.

Intravenous xenotransplantation of human placental mesenchymal stem cells to rats: comparative analysis of homing in rat brain in two models of experimental ischemic stroke

Mesenchymal stem cells from human placenta obtained after term natural delivery were cultured and labeled with vital dye Dil of magnetic fluorescing microparticles. The labeled cells were transplanted intravenously to rats with occlusion of the median cerebral artery. Penetration of cells through the brain-blood barrier and their distribution in the brain of experimental animals were studied on serial cryostat sections. Two models of cerebral artery occlusion associated with different traumatic consequences were used. The efficiency of crossing the blood-brain barrier by transplanted cells, the number of mesenchymal cells attaining the ischemic focus and neurogenic zones, and the time of death of transplanted cells largely depended on the degree and nature of injury to the central nervous system, which should be taken into account when planning the experiments for evaluation of the effects of cell therapy on the models of neurological diseases and in clinical studies in the field of regenerative neurology.

Subpopulation of colorectal adenocarcinoma cells co-expressing CD133 and cancer stem cells markers of other tumors

Co-expression of colorectal adenocarcinoma cancer stem cells marker CD133 and a set of surface molecules described in published reports as possible cancer stem cell markers of other solid tumors was analyzed by flow cytometry. Minor cell populations expressing CD29, CD34, CD90, and CD117 against the background of CD133 expression were detected in cancer cells suspensions from the patients with colorectal adenocarcinoma. Our findings suggest that these markers can be used as additional markers of cancer stem cells of human colorectal adenocarcinoma.

Comparative analysis of expression of human telomerase catalytic subunit at the transcription level in cell cultures of different origin

The expression of human telomerase catalytic subunit in HL-60 and HT-1080 malignant transformed cells and telomerized fibroblasts was studied by quantitative PCR. It was found that the number of transcripts of human telomerase catalytic subunit per cell in telomerized fibroblasts could be hundreds of times higher than in HL-60 and HT-1080 cells. Telomerized fibroblast cultures are suggested as experimental systems for selection of basal compounds for creation of anticancer drug prototypes, the molecular target of which is human telomerase catalytic subunit. The effects of human telomerase catalytic subunit expression on the fibroblast proteome are analyzed.

Mesenchymal cells of the decidual tooth pulp: cytophenotype and initial evaluation of possibility of their use in bone tissue engineering

Cultures of mesenchymal cells from human decidual tooth pulp were derived. The phenotype and capacity to osteogenic and adipogenic differentiation of these cells are close to those of bone marrow mesenchymal stem cells. Decidual tooth pulp mesenchymal cells populate biodegraded polylactide scaffolds and hence, can be used for the creation of tissue engineering transplants for bone defect repair. Storage of decidual tooth pulp mesenchymal cells in the stem cell cryobanks together with umbilical blood will appreciably extent the periods of age for collection of juvenile autologous stem cells for use throughout the life span.

Preparation of mixed keratinocyte and melanocyte cultures from biopsy specimens of pigmented skin sites of patients with vitiligo

A method for preparation and expansion of mixed keratinocyte and melanocyte culture from human skin biopsy specimens was developed. The culture contains two melanocyte types: derivatives of hair follicle stem cells and epidermal basal layer stem cells. Fibroblasts were completely eliminated after culturing in selective medium.

In vitro comparison of immunological properties of cultured human mesenchymal cells from various sources

Cell-mediated cytotoxicity was studied in vitro during the interaction of bone marrow mesenchymal stem cells, fibroblast-like cells from newborn umbilical cord, and skin fibroblasts of an adult donor with peripheral blood mononuclear cells. Independently on the origin, mesenchymal cells were not lysed with allogeneic natural killer cells and cytotoxic lymphocytes. Mixed cultures of mesenchymal cells had no cytotoxic effect on peripheral blood mononuclear cells and did not activate proliferation of T and B lymphocytes, natural killer cells, and CD14+ lymphocytes. In vitro experiments showed that mesenchymal cells of different origin and allogeneic immunocompetent cells are tolerant to each other.

Use of bone marrow mesenchymal (stromal) stem cells in experimental ischemic stroke in rats

The effects of human mesenchymal stem cells on neurological functions and behavioral reactions of animals and on damaged brain tissue were studied on the model of focal cerebral ischemia in rats. Homing and differentiation of transplanted mesenchymal stem cells were also studied. Significant regression of neurological disorders after cell transplantation was noted, no appreciable shifts were detected by magnetic resonance tomography. Homing of transplanted cells was detected mainly in the zone of focal ischemia. Some cells died, others exhibited signs of differentiation into neurons and glia.

Capability of human mesenchymal cells isolated from different sources to differentiation into tissues of mesodermal origin

We compared the capacity of cultured human skin fibroblasts, human umbilical cord cells obtained after normal delivery on gestation week 38-40, and mesenchymal bone marrow stem cells to differentiation into adipocytes, osteoblasts, and chondrocytes. Our findings suggest that mesenchymal stem cells are multipotent cells and can differentiate into adipose, cartilaginous, and bone tissue. Umbilical cord fibroblast-like cells can differentiate into adipocytes and chondrocytes, and only few cells in this culture can differentiate into osteoblasts. Skin fibroblasts differentiate only into adipocytes.

Cytofluorometric analysis of phenotypes of human bone marrow and umbilical fibroblast-like cells

Comparative analysis of the expression of some surface markers of human bone marrow mesenchymal stem cells, umbilical fibroblast-like cells, and skin fibroblasts was carried out by the flow cytofluorometry method. Mesenchymal stem cells and umbilical fibroblast-like cells were similar by the levels of expression of the main histocompatibility complex antigens, adhesion molecules, and some growth factor receptors. The profile of skin fibroblast surface antigens was characterized by higher expression of the markers typical of differentiated cells. The results prove the possibility of using umbilical fibroblast-like cells as an alternative source of mesenchymal stem cells for cell replacement therapy.