Global landscape of SARS-CoV-2 mutations and conserved regions.

BACKGROUND: At the end of December 2019, a novel strain of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) disease (COVID-19) has been identified in Wuhan, a central city in China, and then spread to every corner of the globe. As of October 8, 2022, the total number of COVID-19 cases had reached over 621 million worldwide, with more than 6.56 million confirmed deaths. Since SARS-CoV-2 genome sequences change due to mutation and recombination, it is pivotal to surveil emerging variants and monitor changes for improving pandemic management. METHODS: 10,287,271 SARS-CoV-2 genome sequence samples were downloaded in FASTA format from the GISAID databases from February 24, 2020, to April 2022. Python programming language (version 3.8.0) software was utilized to process FASTA files to identify variants and sequence conservation. The NCBI RefSeq SARS-CoV-2 genome (accession no. NC_045512.2) was considered as the reference sequence. RESULTS: Six mutations had more than 50% frequency in global SARS-CoV-2. These mutations include the P323L (99.3%) in NSP12, D614G (97.6) in S, the T492I (70.4) in NSP4, R203M (62.8%) in N, T60A (61.4%) in Orf9b, and P1228L (50.0%) in NSP3. In the SARS-CoV-2 genome, no mutation was observed in more than 90% of nsp11, nsp7, nsp10, nsp9, nsp8, and nsp16 regions. On the other hand, N, nsp3, S, nsp4, nsp12, and M had the maximum rate of mutations. In the S protein, the highest mutation frequency was observed in aa 508-635(0.77%) and aa 381-508 (0.43%). The highest frequency of mutation was observed in aa 66-88 (2.19%), aa 7-14, and aa 164-246 (2.92%) in M, E, and N proteins, respectively. CONCLUSION: Therefore, monitoring SARS-CoV-2 proteomic changes and detecting hot spots mutations and conserved regions could be applied to improve the SARS-CoV-2 diagnostic efficiency and design safe and effective vaccines against emerging variants.

The effect of mesenchymal stem cells and imatinib on macrophage polarization in rat model of liver fibrosis.

Liver fibrosis is a disorder in which inflammatory reactions play an important role, and central to the progression and pathogenesis of this disease are the immune-specific cells known as macrophages. Macrophage types are distinguished from each other by the expression of a series of surface markers. STAT6 and Arg1 play an important role in the polarization of macrophages, so these two factors are downstream of interleukin 4 (IL-4) and IL-13 cytokines and cause to differentiate M2. Therefore, this study aimed to compare the independent effects of imatinib and mesenchymal cell treatment on the polarization of macrophages in rat models of liver fibrosis. The liver fibrosis was induced by the injection of CCL4 for 6 weeks in Sprague-Dawley rats. Then, rats were divided into four different groups, and the effects of imatinib and mesenchymal cells on the expression of Arg1, Ly6c, and STAT6 were evaluated. Histopathology experiments considered the amelioration effect of treatments. Our results showed that Arg1 expression was significantly increased in the groups treated with mesenchymal cells and imatinib compared to the control group. On the other hand, expression of STAT6 was significantly increased in the imatinib-treated mice compared to mesenchymal and control groups. Moreover, the expression of LY6C significantly decreased in imatinib and mesenchymal treated groups compared to the control group. Therefore, our data showed that mesenchymal stem cells and imatinib significantly modulate the fibrotic process in rat models of fibrosis, probably by polarizing macrophages towards an anti-inflammatory profile and increasing the frequency of these cells in liver tissue.

Imatinib suppresses activation of hepatic stellate cells by targeting STAT3/IL-6 pathway through miR-124.

The activation of hepatic stellate cells is the primary function of facilitating liver fibrosis. Interfering with the coordinators of different signaling pathways in activated hepatic stellate cells (aHSCs) could be a potential approach in ameliorating liver fibrosis. Regarding the illustrated anti-fibrotic effect of imatinib in liver fibrosis, we investigated the imatinib's potential role in inhibiting HSC activation through miR-124 and its interference with the STAT3/hepatic leukemia factor (HLF)/IL-6 circuit. The anti-fibrotic effect of imatinib was investigated in the LX-2 cell line and carbon tetrachloride (CCl4 )-induced Sprague-Dawley rat. The expression of IL-6, STAT3, HLF, miR-124, and α-smooth muscle actin (α-SMA) were quantified by quantitative real-time PCR (qRT-PCR) and the protein level of α-SMA and STAT3 was measured by western blot analysis both in vitro and in vivo. The LX-2 cells were subjected to immunocytochemistry (ICC) for α-SMA expression. After administering imatinib in the liver fibrosis model, histopathological examinations were done, and hepatic function serum markers were checked. Imatinib administration alleviated mentioned liver fibrosis markers. The expression of miR-124 was downregulated, while IL-6/HLF/STAT3 circuit agents were upregulated in vitro and in vivo. Notably, imatinib intervention decreased the expression of IL-6, STAT3, and HLF. Elevated expression of miR-124 suppressed the expression of STAT3 and further inhibited HSCs activation. Our results demonstrated that imatinib not only ameliorated hepatic fibrosis through tyrosine kinase inhibitor (TKI) activity but also interfered with the miR-124 and STAT3/HLF/IL-6 pathway. Considering the important role of miR-124 in regulating liver fibrosis and HSCs activation, imatinib may exert its anti-fibrotic activity through miR-124.

Mutations in SARS-CoV-2 structural proteins: a global analysis.

BACKGROUND: Emergence of new variants mainly variants of concerns (VOC) is caused by mutations in main structural proteins of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Therefore, we aimed to investigate the mutations among structural proteins of SARS-CoV-2 globally. METHODS: We analyzed samples of amino-acid sequences (AASs) for envelope (E), membrane (M), nucleocapsid (N), and spike (S) proteins from the declaration of the coronavirus 2019 (COVID-19) as pandemic to January 2022. The presence and location of mutations were then investigated by aligning the sequences to the reference sequence and categorizing them based on frequency and continent. Finally, the related human genes with the viral structural genes were discovered, and their interactions were reported. RESULTS: The results indicated that the most relative mutations among the E, M, N, and S AASs occurred in the regions of 7 to 14, 66 to 88, 164 to 205, and 508 to 635 AAs, respectively. The most frequent mutations in E, M, N, and S proteins were T9I, I82T, R203M/R203K, and D614G. D614G was the most frequent mutation in all six geographical areas. Following D614G, L18F, A222V, E484K, and N501Y, respectively, were ranked as the most frequent mutations in S protein globally. Besides, A-kinase Anchoring Protein 8 Like (AKAP8L) was shown as the linkage unit between M, E, and E cluster genes. CONCLUSION: Screening the structural protein mutations can help scientists introduce better drug and vaccine development strategies.

Gene expression profile of immunoregulatory cytokines secreted from bone marrow and adipose derived human mesenchymal stem cells in early and late passages.

Mesenchymal Stem Cells (MSCs) have therapeutic potential in a variety of diseases; however, the safety and efficacy of their use remain ambiguous. Clinical applications of MSCs are under intensive investigation due to their immunomodulatory features and lack of immune reactivity. Therefore, having a clear perspective on the exact mechanisms underlying the regulation of cytokine secretion in different microenvironments seems crucially important.In the current study, samples from human bone marrow and adipose were collected, and peripheral blood mononuclear cells (PBMCs) were isolated and cultured in conventional medium. After MSC expansion, the cells from passage 3 (P3) and passage 9 (P9) were utilized to identify MSC cell surface markers and their differentiation capacity. The P3, P5, P7, and P9 cells were used for RNA extraction to qualify the expression of the main immunomodulatory cytokines IDO, VCAM-1, TGF-ß, IL-6, IL-10, and PGE2 at mRNA levels. The results indicate that VCAM-1 expression in the subcultures was reduced in bone marrow-derived MSCs. After an increase in P5, P7, and P9, IL-6 expression was reduced. In adipose-derived MSCs, the mRNA levels of IL-10 in higher passages were decreased compared with P3; other studied cytokines had no significant changes in their expression levels in either bone marrow or adipose-derived MSCs. Based on these results, it can be concluded that a suitable source for MSCs in cell therapy with stable expression of main cytokines, even in higher subcultures, appears to be adipose-derived MSCs with the exception of IL-10 secretion.

Exosomes as a novel cell-free therapeutic approach in gastrointestinal diseases.

Cell communication through extracellular vesicles (EVs) has been defined for many years and it is not limited only to neighboring cells, but also distant ones in organisms receive these signals. These vesicles are secreted from the variety of cells and are composed of a distinctive component such as proteins, lipids, and nucleic acids. EVs have different classified subgroups regarding their cell origin, in this context, exosomes are the most appealing particles in cell biology, especially clinical in recent years and are represented as novel therapeutic agents with numerous advantages alongside and/or over cell therapy. However, cell therapy had a hopeful outcome in gastrointestinal diseases which have minimal alternatives in their treatments. Inflammatory bowel disease (IBD), liver fibrosis, gastrointestinal cancers are the examples that cell therapy and immunotherapy were applied in their treatment, therefore, the cell products like exosomes are the beneficial option in their treatment even cancers with promising results in animal models. In this review, we consider the main defined biogenesis, function, and component of secreted exosomes in different cells with a specific focus on the potential application of these exosomes as a cell-free therapeutic approach in gastrointestinal diseases like IBD, gastric cancer, and colon cancer. Additionally, exosomes role as therapeutic reagents mainly mesenchymal stem cells and dendritic cell-derived exosomes in different studies have been under intense investigation and even they are being studied in different clinical trials. Therefore, all these striking functions described for secretome implies the importance of these biocarriers.

A Simple High Yield Technique for Isolation of Wharton's Jelly-derived Mesenchymal Stem Cell.

Background: The isolation of Mesenchymal Stem Cells (MSCs) from various tissues is possible, with the umbilical cord emerging as a competitive alternative to bone marrow. In order to fulfill the demands of cell therapy, it is essential to generate stem cells on a clinical scale while minimizing time, cost, and contamination. Here is a simple and effective protocol for isolating MSC from Wharton's Jelly (WJ-MSC) using the explant method with various supplements. Methods: Utilizing the explant method, small fragments of Wharton's jelly from the human umbilical cord were cultured in a flask. The multipotency of the isolated cells, were confirmed by their differentiation ability to osteocyte and adipocyte. Additionally, the immunophenotyping of WJ-MSCs showed positive expression of CD73, CD90, and CD105, while remaining negative for hematopoietic markers CD34 and CD45, meeting the criteria for WJ-MSC identification. Following that, to evaluate cells' proliferative capacity, various supplements, including basic Fibroblast Growth Factor (bFGF), Non-Essential amino acids (NEA), and L-Glutamine (L-Gln) were added to either alpha-Minimal Essential Medium (α-MEM) or Dulbecco's Modified Eagle's Medium-F12 (DMEM-F12), as the basic culture media. Results: WJ-MSCs isolated by the explant method were removed from the tissue after seven days and transferred to the culture medium. These cells differentiated into adipocyte and osteocyte lineages, expressing CD73, CD90, and CD105 positively and CD34 and CD45 negatively. The results revealed that addition of bFGF to α-MEM or DMEMF12 media significantly increased the proliferation of MSCs when compared to the control group. However, there were no significant differences observed when NEA or LGln were added. Conclusion: Although bFGF considerably enhances cell proliferation, our study demonstrates that MSCs can grow and expand when properly prepared Wharton's jelly tissues of the human umbilical cord.

Combination of pioglitazone and dendritic cell to optimize efficacy of immune cell therapy in CT26 tumor models.

Introduction: The maturation faith of dendritic cells is restrained by the inflammatory environment and cytokines, such as interleukin-6 and its downstream component. Therefore, introducing the suitable antigen to dendritic cells is crucial. However, reducing the severity of the suppressive tumor microenvironment is indispensable. The present study examined the combination therapy of lymphocyte antigen 6 family member E (LY6E) pulsed mature dendritic cells (LPMDCs) and pioglitazone against colorectal cancer (CRC) to elevate the effectiveness of cancer treatment through probable role of pioglitazone on inhibiting IL-6/STAT3 pathway. Methods: Dendritic cells were generated from murine bone marrow and were pulsed with lymphocyte antigen 6 family member E peptide to assess antigen-specific T-cell proliferation and cytotoxicity assay with Annexin/PI. The effect of pioglitazone on interleukin (IL)-6/STAT3 was evaluated in vitro by real-time polymerase chain reaction (PCR). Afterward, the CRC model was established by subcutaneous injection of CT26, mouse colon carcinoma cell line, in female mice. After treatment, tumor, spleen, and lymph nodes samples were removed for histopathological, ELISA, and real-time PCR analysis. Results: In vitro results revealed the potential of lysate-pulsed dendritic cells in the proliferation of double-positive CD3-8 splenocytes and inducing immunogenic cell death responses, whereas pioglitazone declined the expression of IL-6/STAT3 in colorectal cell lines. In animal models, the recipient of LPMDCs combined with pioglitazone demonstrated high tumor-infiltrating lymphocytes. Elevating the IL-12 and interferon-gamma (IFN-γ) levels and prolonged survival in lysate-pulsed dendritic cell and combination groups were observed. Conclusion: Pioglitazone could efficiently ameliorate the immunosuppressive feature of the tumor microenvironment, mainly through IL-6. Accordingly, applying this drug combined with LPMDCs provoked substantial CD8 positive responses in tumor-challenged animal models.

Comparative Analysis and Identification of Spike Mutations in Iranian COVID-19 Samples from the First Three Waves of Disease.

Background: The spike surface glycoprotein of SARS-CoV-2 is the essential protein in virus attachment to the target cell and cell entrance. As this protein contains immunodominant epitopes and is the main target for immune recognition, it is the critical target for vaccine and therapeutics development. In the current research, we analyzed the variability and mutations of the spike glycoprotein isolated from 72 COVID-19-positive patients from Iran's first three waves of disease. Materials and Methods: The RNA was extracted from nasopharyngeal samples of confirmed COVID-19 cases and served as a template for cDNA synthesis and reverse transcriptase polymerase chain reaction. The reverse transcriptase polymerase chain reaction products of each sample were assembled and sequenced. Results: After analysis of 72 sequences, we obtained 46 single nucleotide polymorphisms, including 23 that produce amino acid changes. Our analysis showed that the most frequent mutation was the D614G (in the samples of the second and third waves). Conclusions: Our findings suggest that developing effective vaccines requires identifying the predominant variants of SARS-CoV-2 in each community.

Fibroblast growth factor 2 reduces endoplasmic reticulum stress and apoptosis in in-vitro Non-Alcoholic Fatty Liver Disease model.

PURPOSE: Non-Alcoholic fatty liver disease is characterized by the accumulation of excess fat in the liver, chronic inflammation, and cell death, ranging from simple steatosis to fibrosis, and finally leads to cirrhosis and hepatocellular carcinoma. The effect of Fibroblast growth factor 2 on apoptosis and ER stress inhibition has been investigated in many studies. In this study, we aimed to investigate the effect of FGF2 on the NAFLD in-vitro model in the HepG2 cell line. METHODS: The in-vitro NAFLD model was first induced on the HepG2 cell line using oleic acid and palmitic acid for 24 h and evaluated by ORO staining and Real-time PCR. The cell line was then treated with various concentrations of fibroblast growth factor 2 for 24 h, total RNA was extracted and cDNA was consequently synthesized. Real-time PCR and flow cytometry was applied to evaluate gene expression and apoptosis rate, respectively. RESULTS: It was shown that fibroblast growth factor 2 ameliorated apoptosis in the NAFLD in-vitro model by reducing the expression of genes involved in the intrinsic apoptosis pathway, including caspase 3 and 9. Moreover, endoplasmic reticulum stress was decreased following upregulating the protective ER-stress genes, including SOD1 and PPARα. CONCLUSIONS: FGF2 significantly reduced ER stress and intrinsic apoptosis pathway. Our data suggest that FGF2 treatment could be a potential therapeutic strategy for NAFLD.

SARS-CoV-2 Non-structural protein 1(NSP1) mutation virulence and natural selection: Evolutionary trends in the six continents.

OBJECTIVE: Rapid transmission and reproduction of RNA viruses prepare conducive conditions to have a high rate of mutations in their genetic sequence. The viral mutations make adapt the severe acute respiratory syndrome coronavirus 2 in the host environment and help the evolution of the virus then also caused a high mortality rate by the virus that threatens worldwide health. Mutations and adaptation help the virus to escape confrontations that are done against it. METHODS: In the present study, we analyzed 6,510,947 sequences of non-structural protein 1 as one of the conserved regions of the virus to find out frequent mutations and substitute amino acids in comparison with the wild type. NSP1 mutations rate divided into continents were different. RESULTS: Based on this continental categorization, E87D in global vision and also in Europe notably increased. The E87D mutation has signed up to January 2022 as the first frequent mutation observed. The remarkable mutations, H110Y and R24C have the second and third frequencies, respectively. CONCLUSION: According to the important role of non-structural protein 1 on the host mRNA translation, developing drug design against the protein could be so hopeful to find more effective ways the control and then treatment of the global pandemic coronavirus disease 2019.

Therapeutic potential of targeting regulatory mechanisms of hepatic stellate cell activation in liver fibrosis.

Hepatic fibrosis is a manifestation of different etiologies of liver disease with the involvement of multiple mediators in complex network interactions. Activated hepatic stellate cells (aHSCs) are the central driver of hepatic fibrosis, given their potential to induce connective tissue formation and extracellular matrix (ECM) protein accumulation. Therefore, identifying the cellular and molecular pathways involved in the activation of HSCs is crucial in gaining mechanistic and therapeutic perspectives to more effectively target the disease. In addition to a comprehensive summary of our current understanding of the role of HSCs in liver fibrosis, we also discuss here the proposed therapeutic strategies based on targeting HSCs.

Contribution of natural killer cells in innate immunity against colorectal cancer.

Natural killer cells are members of the innate immune system and promote cytotoxic activity against tumor or infected cells independently from MHC recognition. NK cells are modulated by the expression of activator/inhibitory receptors. The ratio of this activator/inhibitory receptors is responsible for the cytotoxic activity of NK cells toward the target cells. Owing to the potent anti-tumor properties of NK cells, they are considered as interesting approach in tumor treatment. Colorectal cancer (CRC) is the second most common cause of death in the world and the incidence is about 2 million new cases per year. Metastatic CRC is accompanied by a poor prognosis with less than three years of overall survival. Chemotherapy and surgery are the most adopted treatments. Besides, targeted therapy and immune checkpoint blockade are novel approach to CRC treatment. In these patients, circulating NK cells are a prognostic marker. The main target of CRC immune cell therapy is to improve the tumor cell's recognition and elimination by immune cells. Adaptive NK cell therapy is the milestone to achieve the purpose. Allogeneic NK cell therapy has been widely investigated within clinical trials. In this review, we focus on the NK related approaches including CAR NK cells, cell-based vaccines, monoclonal antibodies and immunomodulatory drugs against CRC tumoral cells.

The First Geographic Identification by Country of Sustainable Mutations of SARS-COV2 Sequence Samples: Worldwide Natural Selection Trends.

The high mutation rates of RNA viruses, coupled with short generation times and large population sizes, allow viruses to evolve rapidly and adapt to the host environment. The rapidity of viral mutation also causes problems in developing successful vaccines and antiviral drugs. With the spread of SARS-CoV-2 worldwide, thousands of mutations have been identified, some of which have relatively high incidences, but their potential impacts on virus characteristics remain unknown. The present study analyzed mutation patterns, SARS-CoV-2 AASs retrieved from the GISAID database containing 10,500,000 samples. Python 3.8.0 programming language was utilized to pre-process FASTA data, align to the reference sequence, and analyze the sequences. Upon completion, all mutations discovered were categorized based on geographical regions and dates. The most stable mutations were found in nsp1(8% S135R), nsp12(99.3% P323L), nsp16 (1.2% R216C), envelope (30.6% T9I), spike (97.6% D614G), and Orf8 (3.5% S24L), and were identified in the United States on April 3, 2020, and England, Gibraltar, and, New Zealand, on January 1, 2020, respectively. The study of mutations is the key to improving understanding of the function of the SARS-CoV-2, and recent information on mutations helps provide strategic planning for the prevention and treatment of this disease. Viral mutation studies could improve the development of vaccines, antiviral drugs, and diagnostic assays designed with high accuracy, specifically useful during pandemics. This knowledge helps to be one step ahead of new emergence variants.

SARS-CoV-2 Non-Structural Protein 1(NSP1) Mutation Virulence and Natural Selection: Evolutionary Trends in the Six Continents.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an unsegmented positivesense single-stranded RNA virus that belongs to the ß-coronavirus . This virus was the cause of a novel severe acute respiratory syndrome in 2019 (COVID-19) that emerged in Wuhan, China at the early stage of the pandemic and rapidly spread around the world. Rapid transmission and reproduction of SARS-CoV-2 threaten worldwide health with a high mortality rate from the virus. According to the significant role of non-structural protein 1 (NSP1) in inhibiting host mRNA translation, this study focuses on the link between amino acid sequences of NSP1 and alterations of them spreading around the world. The SARS-CoV-2 NSP1 protein sequences were analyzed and FASTA files were processed by Python language programming libraries. Reference sequences compared with each NSP1 sample to identify every mutation and categorize them were based on continents and frequencies. NSP1 mutations rate divided into continents were different. Based on continental studies, E87D in global vision and also in Europe notably increased. The E87D mutation has significantly risen especially in the last months of the study as the first frequent mutation observed. The remarkable mutations, H110Y and R24C, have the second and third frequencies, respectively. Based on this mutational information, despite NSP1 being a conserved sequence occurrence, these mutations change the rate of flexibility and stability of the NSP1 protein, which can eventually affect inhibiting the host translation. IMPORTANCE: In this study, we analyzed 6,510,947 sequences of non-structural protein 1 as a conserved region of SARS-CoV-2. According to the obtained results, 93.4819% of samples had no mutant regions on their amino acid sequences. Heat map data of mutational samples demonstrated high percentages of mutations that occurred in the region of 72 to 126 amino acids indicating a hot spot region of the protein. Increased rates of E87D, H110Y, and R24C mutations in the timeline of our study were reported as significant compared to available mutant samples. Analyzing the details of replacing amino acids in the most frequent E87D mutation reveals the role of this alteration in increasing molecule flexibility and destabilizing the structure of the protein.

Dendritic Cell-Based Therapy Using LY6E Peptide with a Putative Role Against Colorectal Cancer.

INTRODUCTION: Albeit early stage gastrointestinal (GI) carcinomas have a good prognosis if treated with surgery, diagnosis is often confirmed at a late stage and efficacious drugs are lacking. Recent progress in immune-based therapies has focused on dendritic cells (DCs), aiming to elicit tumor-specific responses by inducing immunological memory. Our previous microarray study indicated that a biomarker, termed lymphocyte antigen-6E (LY6E), is commonly overexpressed in two potentially lethal GI cancers: those of colon and stomach. In this study, we examined the antigenic potency of LY6E in stimulating DCs. METHODS: Following isolation, differentiation, and maturation of mononuclear cells, DCs were pulsed with LY6E peptide, a protein related to major histocompatibility complex (MHC) class I/II. Subsequently, DCs were co-cultured with mouse splenocytes to assess antigen-specific T-cell proliferation. Elucidated cytotoxic T-lymphocyte responses were assessed using subcutaneous colorectal murine tumor models. RESULTS: Our in vitro results suggest that DCs loaded with LY6E peptide antigen are capable of stimulating and inducing proliferation of murine T-cells. Furthermore, our in vivo results demonstrate that LY6E peptide has a substantial impact on provoking immune responses against induced colon cancer in mice. DISCUSSION: In conclusion, based on the overexpression of LY6E in colorectal, gastric, and pancreatic cancers, the role of this peptide should be further investigated with a goal of developing new therapies for these challenging diseases.

Therapeutic potential of bone marrow-derived mesenchymal stem cells and imatinib in a rat model of liver fibrosis.

Considering the global increase in the prevalence of hepatic fibrosis and ineffective disease treatment, novel therapies are urgently needed. The current study is focused on comparing the therapeutic effects of mesenchymal stem cells (MSC)/imatinib combination therapy to single (MSCs or imatinib) therapy, in a rat model of carbon tetrachloride (CCL4)-induced liver fibrosis. Using rats, hepatic fibrosis was induced by injection of CCL4. Rats were divided into 5 groups: CCL4-induced hepatic fibrosis, phosphate buffered saline (PBS) treatment (vehicle control), Bone marrow-MSCs (BM_MSCs), imatinib, and bone marrow-MSCs/imatinib co-treatment. The therapeutic impact of these approaches was determined using histopathology, sirius-red staining, serum markers, and qRT-PCR for over expression of matrix components. IHC and Western blot were conducted for further confirmation of the results. Single treatment with MSCs or imatinib and the combination therapy, all significantly reduced serum levels of ALT, AST, and ALP concomitant with down-regulation of α-SMA, pro-collagen I, pro-collagen III, collagen IV, and laminin. A significant reduction of ECM components deposits and a decrease in α-SMA expression were detected in all treatment groups. Pathological observations demonstrated that 20% and 40% of the rats in the MSC and MSC/imatinib group were in grade F0 respectively, while 80% of the rats of the imatinib group were in grade 2. Even though all treatment strategies studied resulted in an equally potent reduction in the mRNA and protein expression levels of pro-fibrotic markers, in aspect of pathological observations, our results demonstrate the highest therapeutic potential of utilizing combination of BM-MSCs and imatinib.

Immunoregulatory impact of human mesenchymal-conditioned media and mesenchymal derived exosomes on monocytes.

Mesenchymal stem cells (MSCs) are well known due to their immunomodulatory effect, but the exact mechanisms have not been defined. Several studies demonstrated that the exerted immunoregulatory effect of these cells could be mediated by paracrine factors to illustrate, cytokines, chemokine, and among which, extracellular vesicles are one of them to play a crucial role. Moreover, it is assumed that extracellular vesicles are an essential player in intracellular communication by transferring their component. In this respect, the efficiency of conditioned media and exosomes was compared to illustrate a practical approach to cell-free based therapies. In the current study, we investigated the effect of both MSCs conditioned media (MSC-CM) and MSCs-derived exosomes on the expression of pro-inflammatory and anti-inflammatory cytokines in peripheral blood mononuclear cells (PBMCs). In this regard, isolated PBMCs were treated with MSC-CM and MSC-derived exosome as separated groups. Expression of inflammatory and anti-inflammatory markers was evaluated by Real-time PCR and ELISA. The immunoregulatory effect of MSC-CM on pro-inflammatory and anti-inflammatory genes, such as IL-12b, iNOS, EGR-2, IL-10 with an exception in case of IL-6 was more significant. Whereas in protein levels IL-10 showed the most substantial difference in exosome treated groups. It could be assumed that MSC-CM has more immunoregulatory impact on monocyte in contrast with exosomes.Taken together, by considering the recent approaches to cell-free therapy and the immunoregulatory impact of MSCs, yet relatively little is known about the efficacy of human-MSC-CM and secreted exosome compared with each other.

Paracrine signals of mesenchymal stem cells induce epithelial to mesenchymal transition in gastric cancer cells.

AIM: Given the high similarity of phenotypical and secretory properties of mesenchymal stem cells and fibroblasts, this study investigated the possibility of inducing EMT process by mesenchymal stem cells. BACKGROUND: Annually, more than 13% of deaths worldwide occur due to cancer. One of the main reasons for the high mortality rate is due to the metastasis of cancer stem cells. Induction of metastasis occurs during the EMT process, which can also be stimulated by fibroblast cells. METHODS: Mesenchymal stem cells (MSCs) were isolated and sub-cultured until passage 3 or 4. AGS cells were co-cultured with MSCs for 4 days. As the positive control group, AGS cells were treated with TGF-ß (10ng/ml) for 48h. Finally, the mRNA expression level of Vimentin, ß-catenin, Snail, and E-cadherin as the EMT pattern, were evaluated by RT-PCR technique. RESULTS: Our findings indicated that AGS cells' crosstalk with MSCs significantly upregulated fibroblast markers including Vimentin and Snail expression. However, no significant changes were identified for ß-catenin gene expression. Additionally, AGS treatment with MSCs resulted in diminished E-cadherin in the targeted cells. CONCLUSION: Based on the results, the AGS cells crosstalk with MSCs activates induction of epithelial mesenchymal transition, which is confirmed through the elevation of Vimentin and Snail expression and reduction of E-cadherin expression as a specific epithelial marker. However, it seems that MSc was not effective on Wnt/ ß-catenin signal gastric cancer cell line.

Isolation, differentiation, and characterization of mesenchymal stem cells from human bone marrow.

AIM: We describe the minimum requirements and a simplified method for isolation and characterization of mesenchymal stem cells (MSCs) from human bone marrow. BACKGROUND: MSCs are well known adult stem cells present in many tissues such as adipocytes, chondrocytes, osteoblasts, and neurons. Many isolations and characterization methods have emerged to apply MSCs in the clinical applications, which many of them are expensive and time-consuming. METHODS: MSC isolation was carried out from human bone marrow, and cultured in defined medium. Cultures were maintained at 370C in a humidified atmosphere containing 5% CO2 for 48h. The medium was exchanged every 3-4 days. Adherent cells were characterized according to main criteria defined by ISCT, such as differentiation capability to adipocyte and osteoblast using specific differentiation mediums; also, flow cytometry verified MSC specific markers. RESULTS: Isolated MSCs had a fibroblastic-like appearance with adherent property to the culture plate. Differentiation function was proved with the formation of lipid drops and calcium oxalates on the differentiated MSCs and finally, purified MSCs from bone marrow were positive for cell surface markers, CD73, CD90, and CD105 while being negative for CD34 and CD45. CONCLUSION: These findings confirm that the represented method is capable of isolating MSCs from bone marrow with proven results according to all minimum criteria defined by the International Society for Cellular Therapy (ISCT).