Papers by Seyed Mahmoud Hashemi
Journal of Cellular Biochemistry, 2017
Recent studies have demonstrated the influential role of microbial stimulus in characteristics an... more Recent studies have demonstrated the influential role of microbial stimulus in characteristics and immunomodulatory effects of mesenchymal stem cells (MSCs). Due to the migration of MSCs to infection site, it is of importance to understand the interaction of microbial ligands with MSCs in order to clarify the positive or negative role of MSCs in the control of infection. In this research, we assess leishmanial soluble antigen (LSA)-primed MSCs on macrophage immune responses to lipopolysaccharide (LPS). For this purpose, the effects of both conditioned media (CM) and cell-cell contact of LSA primed MSCs were determined on macrophage responses to LPS. According to the obtained results, MSC-treated macrophages demonstrated an alternatively activated macrophages with higher levels of interleukin-10 (IL-10) and transforming growth factor-alpha (TNF-α) and lower levels of IL-6 and nitric oxide (NO) production as compared to the controls. In addition, phagocytosis of apoptotic thymocytes was induced in MSC-treated macrophages. In conclusion, it seems that MSCs trigger an anti-inflammatory phenotype in macrophages at Leishmania infected sites in order to enhance the induction of immune regulatory cells and clearance of apoptotic cells. This article is protected by copyright. All rights reserved.
Journal of biomedical materials research. Part B, Applied biomaterials, Jan 30, 2016
Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engine... more Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engineering and biological processes to compensate for the shortage of damaged or destroyed liver tissues. We examined the viability, differentiation, and integration of hepatocyte-like cells on an electrospun polyethersulfone (PES) scaffold, derived from human endometrial stem cells (hEnSCs). Natural polymers were separately grafted on plasma-treated PES nanofibers, that is, collagen, heparan sulfate (HS) and collagen-HS. Galactosilated PES (PES-Gal) nanofibrous were created. The engineering and cell growth parameters were considered and compared with each sample. The cellular studies revealed increased cell survival, attachment, and normal morphology on the bioactive natural polymer-grafted scaffolds after 30 days of hepatic differentiation. The chemical and molecular assays displayed hepatocyte differentiation. These cells were also functional, showing glycogen storage, α-fetoprotein, and a...
Iranian biomedical journal, Jul 18, 2016
Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabe... more Islet transplantation could be an ideal alternative treatment to insulin therapy for type 1 diabetes Mellitus (T1DM). This clinical and experimental field requires a model that covers problems such as requiring a large number of functional and viable islets, the optimal transplantation site, and the prevention of islet dispersion. Hence, the methods of choice for isolation of functional islets and transplantation are crucial. The present study has introduced an experimental model that overcomes some critical issues in islet transplantation, including in situ pancreas perfusion by digestive enzymes through common bile duct. In comparison with conventional methods, we inflated the pancreas in Petri dishes with only 1 ml collagenase type XI solution, which was followed by hand-picking isolation or Ficoll gradient separation to purify the islets. Then we used a hydrogel composite in which the islets were embedded and transplanted into the peritoneal cavity of the streptozotocin-induced ...
Yakhteh, 2006
Cell Journal (Yakhteh). Comprehensive Research Information Management System. http://yakhteh.jo.r... more Cell Journal (Yakhteh). Comprehensive Research Information Management System. http://yakhteh.jo.research.ac.ir. ...
Immunopharmacology and immunotoxicology, 2016
Mesenchymal stem cells (MSCs) are cell sources for tissues regeneration. By secretion of soluble ... more Mesenchymal stem cells (MSCs) are cell sources for tissues regeneration. By secretion of soluble factors including transforming growth factor-β (TGF-β1) and nitric oxide (NO), MSCs are also able to regulate the immune system. MSCs have been disclosed in lung and adipose tissues with insufficient comparison between the tissues. In this study, specific differentiation and the expression of surface antigens as well as TGF-β1 and NO productive levels were compared in murine lung-derived MSCs (LMSCs) and adipose tissue-derived MSCs (ADMSCs). MSCs were isolated from murine lung and adipose tissues and cultured. Both cell populations were characterized using multilineage potential and the expression of surface antigenic proteins, CD73, CD105, CD34, CD45, and CD11b. Finally, levels of TGF-β1 and NO were evaluated and compared in ADMSCs and LMSCs. Expression of CD73 and CD105; lack of the expression of CD34, CD45, and CD11b markers; as well as adipocyte and osteocyte differentiations were de...
Immunology Letters, 2016
Mesenchymal stem cells (MSCs) are attracted to inflammation site and switch immune system to modu... more Mesenchymal stem cells (MSCs) are attracted to inflammation site and switch immune system to modulate inflammatory responses. This ability makes MSCs the best candidate cells for stem cell therapy of infection diseases. Therefore, we aimed to evaluate the modulatory effect of adipose-derived MSCs (AD-MSCs) on macrophages in Leishmania (L.) major infection. Macrophages and MSCs were isolated from both susceptible (BALB/c) and resistance (C57BL/6) strains. After co-culture of AD-MSCs with macrophages using a transwell system, we assessed MSCs-educated macrophage responses to L. major infection. Our results indicated suppression in levels of tumor necrosis factor α (TNF-α) and interleukin 10 (IL-10) of MSCs co-cultured macrophages in response to L. major infection. To clarify the effects of this suppression on inflammatory conditions, TNF-α/IL-10 ratio was calculated, indicating an increase in TNF-α/IL-10 ratio in MSCs co-cultured groups. The higher TNF-α/IL-10 ratio was observed in BALB/c macrophages co-cultured with BALB/c MSCs. Nitric oxide (NO) assay presented a significant reduction in the supernatant of all MSCs co-cultured groups compared to control. We observed a significant reduction in phagocytosis of MSCs co-cultured groups in response to L. major infection without any significant differences in the phagocytic index. In conclusion, our results represented a new spectrum of immunomodulation induced by MSCs co-cultured with macrophages in response to L. major infection. The magnitude of immunoregulation was different between BALB/c and C57BL/6 strains. Our findings also showed that MSCs exerted potential effect of M1 polarization due to unequal decrease in levels of TNF-α and IL-10 when we considered TNF-α and IL-10as representatives of M1 and M2 phenotypes, respectively. Induction of inflammatory cytokine milieu and reduction in level of IL-10 provides a new hope for stem cell therapy of leishmaniasis in susceptible models.
Biologicals, 2015
To define the optimal fat harvest site and detect any potential differences in adipose-derived st... more To define the optimal fat harvest site and detect any potential differences in adipose-derived stem cells (ASCs) proliferation properties in camels, aspirates from the abdomen and hump sites were compared. Obtained results revealed that ASCs from both abdomen and hump exhibited spindle-shaped and fibroblast-like morphology with hump-derived ASCs being smaller in size and narrower in overall appearance than abdominal ASCs. Abdominal ASCs required a greater time for proliferation than the hump-derived cells. These results were further confirmed with a tetrazolium-based colorimetric assay (MTT) which showed a greater cell proliferation rate for hump ASCs than for the abdomen. Under inductive conditions, ASCs from both abdominal and hump fat deposits maintained their lineage differentiation potential into adipogenic, chondrogenic, and osteogenic lineages during subsequent passages without any qualitative difference. However, expression of alkaline phosphatase was higher in osteogenic differentiated cells from the hump compared with those of the abdomen. Moreover, the increase in calcium content in hump-derived stem cells was higher than that in abdominal-derived stem cells. In conclusion, our findings revealed that ASCs can be obtained from different anatomical locations, although ASCs from the hump fat region may be the ideal stem cell sources for use in cell-based therapies.
Journal of Biomedical Materials Research Part A, 2015
Neural differentiation of mouse embryonic stem cells in combination with three-dimensional electr... more Neural differentiation of mouse embryonic stem cells in combination with three-dimensional electrospun nanofibers as an artificial extracellular matrix can be utilized to reconstruct a spinal cord defect. In this study, random and parallel-aligned nanofibrous poly ɛ-caprolactone was fabricated using electrospinning. Its hydrophobicity was modified by O2 plasma treatment to facilitate enhanced cell attachment. Embryoid bodies (EBs), which contain all three embryonic germ layers, were cultured on poly ɛ-caprolactone scaffolds to study the effect of fiber orientation on cell morphology and differentiation. Cell morphology and neuron-specific gene and protein expressions were, respectively, evaluated by scanning electron microscopy, real-time polymerase chain reaction, and immunocytochemistry. Although two types of nanofibrous scaffolds showed neural marker expression at the protein level, cells on randomly oriented scaffolds showed short-range topographical guidance and stretched across multiple directions, whereas cells on the parallel scaffolds exhibited long extension with enhanced neuron outgrowth along the fiber, producing oriented extracellular matrix, leading to direct cell migration and nerve regeneration. Quantitative real-time polymerase chain reaction showed that both aligned and random electrospun nanofibers downregulated the precursor neural marker Nestin compared with that in the control group, a gelatin-coated tissue culture plate (T). Analysis also showed higher expression of dorso-ventral neural markers (Isl1/2 and Lim1/2) than motor neuron progenitor markers (Pax6, Nkx6.1, and olig2) in aligned nanofibers than in the T group. Moreover, aligned nanofibers showed higher expression of mature neural specific markers such as β-tub and Map2 than those in the randomly oriented scaffolds. Therefore, we conclude that nanofibers with different orientations can support the neural lineage, but aligned nanofibrous scaffolds are superior candidates to promote the advancement of neural precursors to achieve maturity during the differentiation process. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2015.
Journal of diabetes research, 2015
Regenerative and immunomodulatory properties of mesenchymal stem cells (MSCs) might be applied fo... more Regenerative and immunomodulatory properties of mesenchymal stem cells (MSCs) might be applied for type 1 diabetes mellitus (T1DM) treatment. Thus, we proposed in vitro assessment of adipose tissue-derived MSCs (AT-MSCs) immunomodulation on autoimmune response along with beta cell protection in streptozotocin- (STZ-) induced diabetic C57BL/6 mice model. MSCs were extracted from abdominal adipose tissue of normal mice and cultured to proliferate. Diabetic mice were prepared by administration of multiple low-doses of streptozotocin. Pancreatic islets were isolated from normal mice and splenocytes prepared from normal and diabetic mice. Proliferation, cytokine production, and insulin secretion assays were performed in coculture experiments. AT-MSCs inhibited splenocytes proliferative response to specific (islet lysate) and nonspecific (PHA) triggers in a dose-dependent manner (P < 0.05). Decreased production of proinflammatory cytokines, such as IFN-γ, IL-2, and IL-17, and increased...
Background and Objective: Preeclampsia is one of the most common complications during pregnancy t... more Background and Objective: Preeclampsia is one of the most common complications during pregnancy that occurs after 20th weeks of pregnancy in women with normal blood pressure. The pathophysiology of this disease is unknown. Due to changes in serum level of nitric oxide in women with preeclampsia and also the important role of mesenchymal stem cells in the secretion of nitric oxide as an immunoregulator, in this study, we aimed to evaluate the level of nitric oxide in secretions of adipose tissue-derived mesenchymal stem cells in women with normal pregnancy and patients with preeclampsia. Materials and Methods: Subcutaneous adipose tissue of 10 preeclamptic patients and 10 healthy pregnant women was collected during cesarean operation. After isolation and proliferation of mesenchymal stem cells, capablity of their differentiation and their immunophenotyping charactetistics were assessed. Then, their release of nitric oxide was evaluated using Griess method. Results: Stem cells isolate...
Hepatitis monthly, 2011
Nucleic acid amplification testing is recommended for screening blood donations; however, they ar... more Nucleic acid amplification testing is recommended for screening blood donations; however, they are not widely available in developing countries such as Iranian. Confidential unit exclusion (CUE) gives blood donors the opportunity to confidentially indicate whether their blood is or is not suitable for transfusion to others. Hoewever, its effectiveness in improving blood safety has recently been questioned by the blood banking community. The purpose of this study was to determine the efficacy of CUE in Iran. Data on transfusion-transmitted disease markers (HBs Ag, HCV Ab, HIV Ab, RPR) were extracted from a database of voluntary blood donations in 2006 at the Tehran Blood Transfusion Center. The prevalence of markers were compared between CUE-positive ("should not use") and CUE-negative ("can be used") donations. CUE-positive donations had significantly higher risk of HBV and HCV markers (odds ratio (95% confidence interval)7.5 (5.4-10.5) and 5.3 (2.5-11.3), respec...
International Immunopharmacology, 2015
Plasmacytoid dendritic cell (pDC), plays central role in antiviral immunity. The aim of this stud... more Plasmacytoid dendritic cell (pDC), plays central role in antiviral immunity. The aim of this study was to assess the effect of Flt3 ligand (FL) alone or with L929 fibroblast feeder or L929 conditioned media on differentiation of mouse bone marrow (BM) cells into pDC in vitro. Murine BM cells were cultured with FL or with L929 or conditioned media for 9days. The differentiated cells were analyzed using flow cytometry for PDCA-1, B220 and CXCR4. The relative expression of Stat3, CXCR4, CXCR7, IFN-β, TGF-β and Runx2 in differentiated cells determined by real time PCR. The development of pDC showed up to 19% increase after co-culture of BM cells with fibroblast feeder. Upregulation of Stat3, Runx2 and CXCR4 due to the presence of fibroblast feeder with FL in culture results in improved pDC development. Furthermore, 30% L929 supernatant along with Flt3 ligand was able to derive pDC up to 8.9% in comparison with FL alone, which was 6.6% in vitro. Thus, for the first time we introduced L929 fibroblast feeder as a niche producer of M-CSF and probably other growth factors and chemokines, which promotes the development of pDC in vitro along with FL, similar to in vivo niche.
Journal of Cellular Biochemistry, 2015
MicroRNAs play an important role in neuronal development and function. miR-124 is the most abunda... more MicroRNAs play an important role in neuronal development and function. miR-124 is the most abundantly expressed miRNA in the nervous system. Several different mRNA targets have been proposed for miR-124, but the precise function of endogenous miR-124 and its mRNA targets remain to be further elucidated. Specificity protein 1 (Sp1) is a transcription factor that plays key roles in many cell processes including cell cycle. However, this transcription factor is nearly absent in differentiated neurons and a remarkable suppression of Sp1 expression was shown after neurogenesis. Since miR-124 is expressed abundantly in neurons and because Sp1 levels decrease during neurogenesis, it is possible that miR-124 could regulate the expression of Sp1 during neuronal development. Therefore, the aim of the present study was to evaluate the putative targeting of Sp1 by miR-124. Overexpression of miR-124 using a plasmid coding for pri-miR-124 in HEK293 cells decreased the expression of Sp1 mRNA. The results of dual-luciferase reporter assay demonstrated that miR-124 directly targeted the 3&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-untranslated regions of Sp1 mRNA. To evaluate whether Sp1 expression was regulated by miR-124 during the process of neuronal differentiation, Adipose-derived mesenchymal stem cells (A-MSCs) were differentiated into neuron-like cells. The results of qPCR analysis showed that with the gradual increase of miR-124 expression during neurogenesis, the expression of Sp1 mRNA decreased accordingly. In summary, this study demonstrated for the first time that miR-124 is able to suppress Sp1 expression, which in turn affected the neuronal differentiation of mesenchymal stem cells. This article is protected by copyright. All rights reserved.
Applied Immunohistochemistry & Molecular Morphology, 2014
miR-122 is a liver-specific miRNA that has significant gene expression alterations in response to... more miR-122 is a liver-specific miRNA that has significant gene expression alterations in response to specific pathophysiological circumstances of liver such as drug-induced liver injury, hepatocellular carcinoma, and hepatitis B and C virus infections. Therefore, accurate and precise quantification of miR-122 is very important for clinical diagnostics. However, because of the lack of in vitro diagnostics assays for miR-122 detection and quantification of the existence of an open-source assay could inevitably provide external evaluation by other researchers and the chance of promoting the assay when required. The aim of this study was to develop a Taqman real-time polymerase chain reaction assay, which is capable of robust and reliable quantification of miR-122 in different sample types. We used stem loop methodology to design a specific Taqman real-time polymerase chain reaction assay for miR-122. This technique enabled us to reliably and reproducibly quantify short-length oligonucleotides such as miR-122. The specificity, sensitivity, interassay and intra-assay, and the dynamic range of the assay were experimentally determined by their respective methodology. The assay had a linear dynamic range of 3E to 4.8E miR-122 copies/reaction and the limit of detection was determined to be between 960 and 192 copies/reaction with 95% confidence interval. The assay gave a coefficient of variation for the Ct values of &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;1.4% and 0.78% for intra-assay and interassay, respectively. Taking into account that miR-122 is expressed in &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;50,000 copies per hepatocyte, this assay is able to suffice the need for reliable detection and quantification of this miRNA. Therefore, this study can be considered as a start point for standardizing miR-122 quantification.
International Immunopharmacology, 2014
It has been proposed that the immunomodulatory properties of mesenchymal stem cells (MSCs) play a... more It has been proposed that the immunomodulatory properties of mesenchymal stem cells (MSCs) play a crucial role in establishing and leading T lymphocytes, especially Th cell subsets, toward different functional subsets. To determine the effect of the immunomodulatory and regulatory functions of adipose-derived MSCs (AD-MSCs) on C57BL/6 spleen-isolated mononuclear cells (Spleen-MNCs), the gene expression of well-known effector and regulatory Th cell-related transcription factors, i.e., t-bet, GATA-3, Ror-γt and Foxp3, and their related cytokines, i.e., IFN-γ for Th1 cells, IL-4 for Th2 cells, IL-17 for Th17 cells and IL-10 and TGF-β for regulatory T cells, was studied using a co-culture condition system. The proliferation index of Spleen-MNCs was analyzed using a cell proliferation assay kit that utilized the CFSE staining method. Our findings indicate that AD-MSCs greatly impact the up-regulation of immunomodulatory cytokines, such as TGF-β (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001), and the down-regulation of inflammatory cytokines, such as IFN-γ (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.005), and transcription factors, such as t-bet (p&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.001). Considering the immunomodulatory effects of MSCs in the differentiation of Th cell subsets, understanding and harnessing this property of MSCs could be a powerful strategy in the treatment of inflammatory autoimmune diseases such as multiple sclerosis.
Chinese Science Bulletin, 2008
Cardiovascular Revascularization Medicine, 2007
Yakhteh Medical Journal, 2008
Objective: Purple cone flower plant (Echinacea purpurea) is one of the most important Herbal prod... more Objective: Purple cone flower plant (Echinacea purpurea) is one of the most important Herbal products in many countries. Up to now a lot of experiments demonstrated the controversial effects of this herb on immune system . In this research we study the in vivo and in vitro effect of Iranian E.purpurea extract on cellular immunity. Materials and Methods: At first we determined the lethal dose of E.purpurea extract after intraperitoneal injection in BALB/c mice. Then we made five groups of mice and treat them by four times intraperitoneal injection of 1 ml extract at different doses (0, 0.4, 2, 10 and 50 mg/ml) during two weeks. Splenocyte proliferation response to extract was assessed by MTT method. Delayed-Type Hypersensitivity (DTH) response was evaluated by priming mice with 1×10 8 Sheep Red Blood Cell (SRBC) injected subcutaneously in the back on day 7after treatment. Results: As a result no significant variation in weight and spleen index of test groups to control was observed. Splenocyte proliferation and DTH response of test groups to control increased significantly (p<0.05). Conclusion: However these data confirmed the results of previous studies, in addition presented the first results about significant increase in DTH response that could not be seen before. Scince the main reason of this difference refers to active compounds of herb extract, comparing effective component of this extract with that of E.purpurea cultivated in other geographical condition will consider as the next studies.
Modares Journal of Medical Sciences: Pathobiology, Jan 4, 2012
Objective: This study investigated the effects of adipose-derived mesenchymal stem cells (MSCs) a... more Objective: This study investigated the effects of adipose-derived mesenchymal stem cells (MSCs) and conditioned medium injection on cell infiltration in the brains of an experimental C57BL/6 mice model of autoimmune encephalomyelitis (EAE). Methods: EAE was induced with myelin oligodendrocyte glycoprotein (35-55 peptides) in 20 mice. MSCs were obtained from the adipose tissue of C57BL/6 mice and cultured with Eagle's minimum essential medium/alpha medium (DMEM) after removal of non-adherent cells. After 2 to 3 passages, ...
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Papers by Seyed Mahmoud Hashemi