Differential Expression of the hTERT Gene in Umbilical Cord-Derived Mesenchymal Stem Cells Cocultured with B Cell Precursor Leukemia Cell Microparticles or CD41/CD61 Platelet Microparticles.

Several investigations are being done to increase the short lifetime of mesenchymal stem cells (MSCs). One of the crucial genes involved in the immortalization of MSCs, hTERT (human telomerase reverse transcriptase), is activated in most publications using viral-based techniques. In this work, we investigated the use of platelet-derived (PMPs) and B cell precursor leukemia-derived microparticles as a nonviral method to trigger and compare the expression of the hTERT gene in MSCs.

An open-label phase 1 clinical trial of the allogeneic side population adipose-derived mesenchymal stem cells in SMA type 1 patients.

Introduction: Spinal muscular atrophy (SMA), an autosomal recessive neurodegenerative disorder of alpha motor neurons of spinal cord associated with progressive muscle weakness and hypotonia, is the most common genetic cause of infant mortality. Although there is few promising treatment for SMA, but the field of translational research is active in it, and stem cell-based therapy clinical trials or case studies are ongoing. Combination of different therapeutic approaches for noncurative treatments may increase their effectiveness and compliance of patients.

Comparison of the effects of intramyocardial and intravenous injections of human mesenchymal stem cells on cardiac regeneration after heart failure.

Objectives: Existing studies have demonstrated that intravenous and intramyocardial-administrated mesenchymal stem cells (MSCs) lead to tissue repair after cardiac disorders. We compared the efficiency of both administration methods.

Materials And Methods: A rat model of isoproterenol-induced heart failure (ISO-HF) was established to compare the effects of intravenous and intramyocardial-administrated MSCs on cardiac fibrosis and function.

Platelets Apoptosis and Clearance in The Presence of Sodium Octanoate during Storage of Platelet Concentrate at 4˚C.

Objective: Platelet (PLT) storage at 4˚C has several benefits, however, it is accompanied by increased clearance of PLTs after transfusion. In this study, we evaluated the potential of sodium octanoate (SO) for reducing apoptosis and clearance rate of PLTs after long-term storage in cold.

Materials And Methods: In this experimental study, PLT concentrates (PCs) were stored for 5 days under the following three conditions: 20-24˚C, 4˚C, and 4˚C in the presence of SO.

Procoagulant Activity of Red Blood Cell-Derived Microvesicles during Red Cell Storage.

Background: Red blood cells (RBCs) undergo structural and biochemical alterations during storage which are collectively called RBC storage lesion and cause a decrease in RBC recovery and survival. During storage, erythrocytes release an increasing number of microvesicles (MVs) that have key roles in biological processes. We aimed to investigate the procoagulant activity (PCA) of RBC-derived MVs during storage.

Conditioned medium obtained from human amniotic mesenchymal stem cells attenuates focal cerebral ischemia/reperfusion injury in rats by targeting mTOR pathway.

Conditioned medium obtained from human amniotic mesenchymal stem cells (hAMSC-CM) was recently shown to have many antioxidant, antiapoptotic and proangiogenic growth factors. The present study was performed to investigate whether protective effects of hAMSC-CM against focal cerebral ischemia/ reperfusion (I/R) injury is associated with modulation of the mammalian target of rapamycin (mTOR) pathway. A rat model of middle cerebral artery occlusion (MCAO) was created and the animals were divided into three groups including sham, MCAO and MCAO + hAMSC-CM.

High Glucose Affects the Cytotoxic Potential of Rapamycin, Metformin and Hydrogen Peroxide in Cultured Human Mesenchymal Stem Cells.

Background: Oxidative stress and chronic hyperglycemia are two major side effects of type 2 diabetes affecting all cell types including mesenchymal stem cells (MSCs). As a cell therapy choice, understanding the behavior of MSCs will provide crucial information for efficient treatment.

Methods: Placental mesenchymal stem cells were treated with various concentrations of glucose, metformin, rapamycin, and hydrogen peroxide to monitor their viability and cell cycle distribution.

microRNA expression profiles in two- and three-dimensional culture conditions of human-umbilical-cord blood-derived CD34 cells.

Human umbilical cord blood (HUCB) is a suitable source of hematopoietic stem cells (HSCs) for therapeutic transplantation. Different approaches have been used to expand the number of HSCs to increase the rate of HSC transplantation success in patients, such as using different cocktails of cytokines, feeder cell layers, and biocompatible scaffolds. microRNAs (miRNAs) are small noncoding RNAs that regulate gene expression posttranscriptionally.

Overexpression of SMN2 Gene in Motoneuron-Like Cells Differentiated from Adipose-Derived Mesenchymal Stem Cells by Ponasterone A.

Cell therapy and stem cell transplantation strategies have provided potential therapeutic approaches for the treatment of neurological disorders. Adipose-derived mesenchymal stem cells (ADMSCs) are abundant adult stem cells with low immunogenicity, which can be used for allogeneic cell replacement therapies. Differentiation of ADMSCs into acetylcholine-secreting motoneurons (MNs) is a promising treatment for MN diseases, such as spinal muscular atrophy (SMA), which is associated with the level of SMN1 gene expression.

The membrane mesenchymal stem cell derived conditioned medium exerts neuroprotection against focal cerebral ischemia by targeting apoptosis.

Objective: The mesenchymal stem cells derived from human amniotic membrane have the ability to secrete and release some factors that can promote the repair of damaged tissues. This secretome contains proteins and factors that reduce apoptosis and increase angiogenesis in the ischemia/reperfusion models. The present study was conducted to determine whether this secretome provides protection against transient focal cerebral ischemia.

Interaction of Platelet-Derived Microparticles with a Human B-Lymphoblast Cell Line: A Clue for the Immunologic Function of the Microparticles.

Background: Platelets are blood cells with extensive capabilities in hemostasis. They also play a central role in the development of innate and adaptive immune responses. Little information exists about the immunostimulatory role of platelet-derived microparticles (Plt-MPs).

Harmine, a Novel DNA Methyltransferase 1 Inhibitor in the Leukemia Cell Line.

DNA methylation followed by tumor suppressor gene repression plays a critical role in the leukemia development. So, DNA methyl transferase inhibitors have great importance in treatment of theses malignancies. Harmine, A beta carboline alkaloid derivative of Peganum harmala, had shown anti- proliferative effects on leukemic cell line.

Elevated expression of DNMT1 is associated with increased expansion and proliferation of hematopoietic stem cells co-cultured with human MSCs.

Background: Mesenchymal stem cells (MSCs) play an important role in hematopoietic stem cell (HSC) maintenance, proliferation, and apoptosis. DNA methyltransferase 1 (DNMT1) is considered an essential factor in the maintenance of HSCs in mammalian cells. Therefore, this study was conducted to evaluate the mRNA expression level of DNMT1 during cord blood (CB)-HSC ex vivo expansion with MSCs.

Evaluation of Plasma Platelet Microparticles in Thrombotic Thrombocytopenic Purpura.

Background: Platelet microparticles (PMPs) have a procoagulant activity about 50-100 times greater than active platelets due to high expression of negatively charged phospholipids on their surfaces. In this study, we evaluated microparticle immunophenotyping and also plasma PMPs level in patients with Thrombotic Thrombocytopenic Purpura (TTP) in Southern Iran.

Method: We had two study groups: 15 TTP patients and 15 healthy control group and PMPs from platelet concentrate (PC) at the 5 day of storage.

Evaluation of umbilical cord blood CD34+ hematopoietic stem cells expansion with inhibition of TGF-β receptorII in co-culture with bone marrow mesenchymal stromal cells.

Background: Umbilical cord blood (UCB) is an important source of hematopoietic stem cells (HSCs). However, low number of HSCs in UCB has been an obstacle for adult hematopoietic stem cell transplantation. The expansion of HSCs in culture is one approach to overcome this problem.

Apoptosis, DAP-Kinase1 Expression and the Influences of Cytokine Milieu and Mesenchymal Stromal Cells on Ex Vivo Expansion of Umbilical Cord Blood-Derived Hematopoietic Stem Cells.

Expansion of umbilical cord blood-derived CD34(+) cells can potentially provide them in numbers sufficient for clinical applications in adult humans. In this study apoptosis rate of expanded cells, mRNA expression and promoter methylation status of DAPK1 were evaluated during cord blood hematopoietic stem cell (CB-HSC) ex vivo expansion using cytokines and a co-culture system with mesenchymal stromal cells (MSCs). Ex vivo cultures of CB-HSCs were performed in three culture conditions for 14 days: cytokines with MSCs feeder layer, cytokines without MSCs feeder layer and co-culture with MSCs feeder layer without cytokine.

The Immunosuppressive Activity of Amniotic Membrane Mesenchymal Stem Cells on T Lymphocytes.

Background: Mesenchymal Stem Cells (MSCs) are isolated from different sources like placenta. The placenta and its membranes like Amniotic Membrane (AM) are readily available and easy to work with. There is only limited knowledge on the immunomodulatory properties of human Amniotic Membrane-derived Mesenchymal Stem Cells (hAM-MSCs).

Evaluation of human cord blood CD34+ hematopoietic stem cell differentiation to megakaryocyte on aminated PES nanofiber scaffold compare to 2-D culture system.

Context: Recently, umbilical cord blood (UCB) has been recognized as a suitable potential source of hematopoietic stem/progenitor cells (HSPCs) for transplantation. Lengthy thrombocytopenia after UCB transplantation is a major problem because of insufficient megakaryocyte (Mk) progenitors, which results in delayed platelet recovery. Frequent allogenic platelet transfusion leads to resistance to platelet units and higher risk of transmission of pathogenic agent.

Biological parameters influencing the human umbilical cord-derived mesenchymal stem cells' response to retinoic acid.

Human umbilical cord-derived mesenchymal stem cells (HUCMSCs) are multipotent fetal stem cells that differentiate into various cell lineages. In recent years, they have gained attention for therapeutic applications but very little is known about their sensitivity to chemical agents such as widely used retinoic acid (RA). As a morphogen inducing differentiation of mesenchymal stem cells, RA has for a long time been known to be a potent teratogen promoting craniofacial and limb abnormality in vertebrate embryos.

The immunophenotype of bone marrow lymphocytes in children with immune thrombocytopenic purpura.

Purpose: Primary immune thrombocytopenic purpura (ITP), caused by immune system dysfunction, is recognized as the leading cause of thrombocytopenia in pediatric population. Nonetheless, inadequate studies have been performed on bone marrow immunophenotyping of children with ITP. In this study, we aimed to investigate the immunophenotype of bone marrow lymphocytes in these children.

Expression and promoter methylation changes of the P15INK4b during ex vivo cord blood CD34+ cell expansion following co-culture with mesenchymal stromal cells.

Background: Because of the insufficient number of cord blood hematopoietic stem cells (CB-HSC), expansion of these cells seems to be important for clinical application in adults. Cell cycle inhibitors are important regulators in normal hematopoietic regeneration. In this study, mRNA expression and promoter methylation status of p15(INK4b) were evaluated during CB-HSC ex vivo expansion using cytokines and in co-culture system with a mesenchymal stem cells (MSCs) feeder layer.

Expression of P16 cell cycle inhibitor in human cord blood CD34+ expanded cells following co-culture with bone marrow-derived mesenchymal stem cells.

Background: Because of insufficient number of cord blood hematopoietic stem cells (CB-HSC), expansion of these cells seems to be important for clinical application in adults. Cell cycle inhibitors are important regulators in normal hematopoietic regeneration. In this study, mRNA expression and promoter methylation status of p16 were evaluated during CB-HSC ex vivo expansion using cytokines and a co-culture system with mesenchymal stem cells (MSCs) feeder layer.

mRNA expression and promoter DNA methylation status of CDKi p21 and p57 genes in ex vivo expanded CD34 (+) cells following co-culture with mesenchymal stromal cells and growth factors.

Background: Several studies indicate that ex vivo cytokine-based expansion of cord blood (CB) CD34(+) cells can induce cell cycle abnormality in expanded cells. Cycline-dependent kinase inhibitors, p21 and p57, are critical regulators of cell cycle. We investigated mRNA expression and promoter DNA methylation status of p21 and p57 genes in ex vivo expanded CD34(+) cells in different culture conditions.

Multidrug resistance inhibition by antisense oligonucleotide against MDR1/mRNA in P-glycoprotein expressing leukemic cells.

Introduction: Acute myeloblastic leukemia (AML) is the most common form of acute leukemia in adults. One major problem in this disease is the emergence of leukemic blast cells that are resistant to anticancer drugs. This phenomenon is termed multidrug resistance (MDR).

Immunosuppressive effect of pregnant mouse serum on allostimulatory activity of dendritic cells.

In normal pregnancy, the maternal immune system is directed towards tolerance or suppression in order to prevent rejection of the semi-allogenic fetus. Antigen-presenting cells, especially dendritic cells (DCs), are key cells in initiation and regulation of immune responses. The presence of potent immunostimulatory DCs in the decidual tissue of pregnancy has been demonstrated.