Enriched Satellite Cells with Pre-plate Technique Differentiate Strongly on Electrospun Polyacrylonitril Membrane

Introduction: Satellite cells known as the main regenerating cell types in skeletal muscle which can be isolated using pre-plate technique due to weak or slow adhesive interactions with satellite cells. Although, there are some issues about digestion of muscle tissue and isolation of satellite cells, which highlight need for an efficient procedure. Also, the employment of a nanofibrous surface can facilitate the attachment of satellite cells to reach matured muscle tissue. On the other hand, polyacrylonitrile (PAN) has been reported as a biocompatible polymer that can be electrospun into a nonwoven membrane. Materials and Methods: Herein, a modified digestion and pre-plate protocol was established for the enrichment of satellite cells. Also, a PAN electrospun scaffold was used to provide a higher surface area for cell attachment compared to tissue culture polystyrene (TCPS). However, the surface of prepared scaffold was modified with plasma treatment to progress cell adhesion. Results: The corresponding scaffold was examined with scanning electron microscopy (SEM) and tensile examination. The enriched cells, which exhibited a close gene expression pattern with satellite cells, seeded on this electrospun PAN membrane. The cultured satellite cells showed a good tendency to surface of PAN scaffold and also a higher rate of cell proliferation. Subsequently, the cells were induced to more expression of specific muscle genes compared to TCPS group. Conclusion: As a whole, satellite cells could mature to multinuclear cells using PAN scaffold as a function of efficient mechanical property and also higher surface area.

The Effect of miR-372 on Genome Instability in MKN-45 Cell Line

Background: Gastric cancer is one of the most common cancers in the world and the second leading cause of cancer mortality in humans. MicroRNAs are a group of endogenous RNA, small non-coding nucleotides in length of 21-23. Overexpression of miR-372 acts as an oncomir in various types of cancer via down-regulation of its target, LATS2. Down-regulation of LATS2 leads to the loss of cell cycle regulation, apoptosis inhibition, and increased proliferation rate of the cells. Methods: In this study, we increased the expression of miR-372 with lentivirus transduction inside the GC cell line MKN-45. After selection of positive cells, miR-372 and LATS2 expression levels were measured through real-time polymerase chain reaction (RT-PCR) assay. Cytochalasin B blocked (MN) assay was done to verify the presence or absence of MN for comparing genomic instability in treated cells compared to the controls. Findings: In the treated cells, compared with the controls, the amount of miR-372 expression significantly increased. Fold changes in 7, 14 and 21 days after the transduction were 7.85, 50.22 and 114.68, respectively (P = 0.030). In contrast to the control cells, the fold changes of LATS2 expression in these days were 0.39, 0.29 and 0.15, respectively (P = 0. 016). In addition, compared with control cells, the genomic instability of treated cells increased significantly (P < 0.001). Conclusion: These results indicate that in MKN-45 cell line, LATS2 is a target of miR-372. LATS2 is down-regulated with increased expression of miR-372. Reduce LATS2, leads to genomic instability during cell division and creates micronuclei and hence may be an important tumor suppressor

Natural killer cell biology and its effect on graft versus host disease

Natural killer (NK) cells were originally described in terms of their function. NK cells are of lymphoid origin and are found in the peripheral blood, spleen, and bone marrow, as well as other tissues. These cells are large, radio-resistant and granular lymphocytes that represent an important arm of innate immunity and are thought to play a critical role in the immune surveillance against tumors and virally infected cells. Allogeneic bone marrow transplantation (BMT) has proven to be an effective treatment for hematologic malignancies and some solid tumors. One of the major challenges of allo-stem cell transplantation (SCT) is to reduce the incidence and severity of GVHD while boosting the graft-versus-leukemia (GVL) effect. In the setting of allo-SCT, the reconstitution of NK cells is of notable interest due to their known capability to induce GVL without GVHD. Clinical applications of NK cells have been inspired by recognition of their potent anticancer activity. These studies discussed a solid basis for development of future NK cell trials for cancer therapy by minimizing risks and toxicities

Optimizing Hydrocortisone Concentration for Skeletal Muscles Differentiation of ADSCs on PLLA Nano-Scaffolds

Skeletal muscle is a highly differentiated tissue with very specific functions which has low potential of regeneration. Skeletal muscle injuries especially in athletes almost have lead to muscular dysfunctions and healing may be prolonged for several years. Therefore, working on skeletal muscle differentiation remained an importance in biomedical researches. Adipose derived stem cells (ADSCs) are novel source of mesenchymal stem cells which are an excellent alternative for satellite cells in in-vitro skeletal muscle differentiation. Differentiation potential of ADSCs on both tissue culture plate (TCP) and also on Poly l-lactide acid (PLLA) electrospun fibrous nano-scaffold which now is widely used at tissue engineering investigations has studied in this research. Scanning electron microscopy (SEM) and Tensile test were performed for evaluating scaffold properties. Hydrocortisone has considered a critical factors for skeletal muscle differentiation while, the recommended concentrations of it for inducing myogenesis in stem cells is yet discussing. Statistical analysis of our results from colorimetric MTT assay for various concentrations of hydrocortisone showed that the concentration of 10-7 mol/L is the optimum dose for myogenic differentiation of murine ADSCs which was used on both TCP and PLLA scaffolds and skeletal myosin fiber formations was confirmed with immunocytochemistry. DAPI staining proved myocytes nuclei and syncytium formations. Our results also showed that ADSCs and PLLA nano-scaffolds are the suitable biomaterials for engineering skeletal muscle tissue.    

Induced pluripotent stem cells: Generation methods and a new perspective in COVID-19 research

Induced pluripotent stem cells (iPSCs) exhibit an unlimited ability to self-renew and produce various differentiated cell types, thereby creating high hopes for both scientists and patients as a great tool for basic research as well as for regenerative medicine purposes. The availability and safety of iPSCs for therapeutic purposes require safe and highly efficient methods for production of these cells. Different methods have been used to produce iPSCs, each of which has advantages and disadvantages. Studying these methods would be very helpful in developing an easy, safe, and efficient method for the generation of iPSCs. Since iPSCs can be generated from somatic cells, they can be considered as valuable cellular resources available for important research needs and various therapeutic purposes. Coronavirus disease 2019 (COVID-19) is a disease that has endangered numerous human lives worldwide and currently has no definitive cure. Therefore, researchers have been rigorously studying and examining all aspects of COVID-19 and potential treatment modalities and various drugs in order to enable the treatment, control, and prevention of COVID-19. iPSCs have become one of the most attractive and promising tools in this field by providing the ability to study COVID-19 and the effectiveness of drugs on this disease outside the human body. In this study, we discuss the different methods of generation of iPSCs as well as their respective advantages and disadvantages. We also present recent applications of iPSCs in the study and treatment of COVID-19

Evaluation of CXCR4, VLA4, and VLA5 expression in peripheral mobilized hematopoietic stem cells in presence of Sotalol

     Hematopoietic stem cells (HSC), are considered as an important source for HSCT transplantation. There are several regulators for stem cells migration and homing, among which the nervous system is an important one. This study is going to investigate the   role of nervous system in homing of hematopoietic stem cells.In an experimental study, mononuclear cells were isolated from peripheral blood and treated by a beta adrenergic receptors blocker (Sotalol). After treating the cells with different concentrations 0.5- 500 (mM/ml) for 1- 24 hours, RNA was extracted and the expression of VLA4, VLA5 and CXCR4 genes were determinated through RT-PCR method.The results of this study demonstrated high expression in genes associated with homing of the cells after being treated with drug for 1 hour: CXCR4 gene expression increases in 10 and 50 mM/ml, VLA4 gene expression in 50mM/ml and VLA5 gene expression in 10 mM/ml concentration of Sotalol.Using beta adrenergic receptors blockers in appropriate time and dose of drug can affect the expression of genes which involved in HSCs homing and will lead to high success rate of transplantation of these cells

Fabrication and Characterization of Covalently Functionalized poly Caprolactone Scaffold for Bone Tissue Engineering Application

Background: Healing bone involves osteoconductive and osteoinductive components as well as a scaffold with adequate porosity to allow good cell infiltration.Materials and Methods: Herein, cytocompatibility and osteogenic induction potential of polycaprolactone (PCL) nanofibrous electrospun scaffold with different electron microscopy, MTT assay, DAPI and alizarin porosities (35%-90%) and chemical bonding was assessed through scanning red S staining, calcium content and alkaline phosphatase assay. Moreover, the relative expression of three important osteogenic-related genes Col I, RUNX 2 and osteocalcin was studied.Results: Covalent bonding played a more significant osteogenic role in scaffolds in scaffolds with lower porosity, namely H35cov. Although low porosity limits cell infiltration, substrate with lower porosities were easier to handle. On the other hand, substrates with higher porosity showed higher levels of cell proliferation, mineralization as well as osteogenic differentiation.Conclusion: Results indicated that PCL scaffold with higher porosity degree up to 90%, covalently functionalized by collagen, and hydroxyapatite nanoparticles was a good candidate for bone tissue engineering applications

Isolation of a 60 kDa protein with in vitro anticancer activity against human cancer cell lines from the purple fluid of the Persian Gulf sea hare, Aplysia dactylomela

Sea hares have greatly attracted the interest of all those investigating chemical defense substances. Most of these substances are low molecular weight compounds derived from algal diets. In vitro anticancer effect of a 60 kDa protein isolated from the purple fluid of Aplysia dactylomela on four human cancer cell lines was investigated in this study. A 60 kDa protein was purified from secreted purple fluid of A. dactylomela, a sea hare from Persian Gulf. The protein purification procedure consisted basically of ammonium sulfate precipitation, ion exchange chromatography using DEAE– Sepharose and ultra-filtration method. In vitro antiproliferative and cytotoxic activity of the protein of interest were evaluated on L929, K562, HL60 and NB4 human cancer cell lines. The antiproliferative and cytotxic effects of 60 kDa protein on human cancer cell lines were measured by MTT assay. Results showed that the 60 kDa protein of the purple fluid of A. dactylomela exhibited the antiproliferative effect on human cancer cell lines, especially on NB4 cell line. It was maximally active at 0.5 – 1.5 μg/ml on NB4 cell line. Interestingly, the protein did not show significant cytotoxic effects

Pre-Differentiated Embryonic Stem Cell versus Olfactory Ensheathing Cell for Spinal Cord Regeneration after Compressive Injury in Rat

Background: Transplantation approaches are interventions currently available to apply to the devastating problem of spinal cord injury (SCI). Olfactory ensheathing cell (OEC) and embryonic stem cell (ESC) are considered to be promising therapeutic strategies. In this study, we compared the potential use of OECs and neurally pre-differentiated ESCs in contusion spinal cord.Methods: OECs were harvested from olfactory bulb of rats and labeled with Hoescht 33342. ESCs were generated by using feeder free GFP positive CGR8 mouse ESCs and neurally pre-differentiation was induced by retinoic acid (RA) and characterized by different antibodies. SCI was induced by fogarty catheter at T8-T9 level in adult rats. Transplantations were performed 9 days after the injury. Rats were randomly divided into 3 main groups (neurally pre-differentiated ESC, OEC and media as control group). The recovery of gross motor function was evaluated using Basso-Beattie-Bresnahan (BBB) locomotor rating scale on the ninth day post injury and once per week thereafter for 4 weeks after cell transplantation. At 28 days after transplantation, histological assessment including transplanted cell detection in tissue, tissue sparing and myelinated axons was performed.Results: Following transplantation, a significant recovery of hindlimb function according to BBB scale was observed in rats in the transplanted groups compared to control and sham groups (p&lt;0.05). There was no significant difference between transplanted groups four weeks after transplantation. OEC and ESC were found in the tissue after transplantation. In OEC group, many of OECs were detected around and within the cystic cavity that number of these cells was significantly higher in comparison with number of cells in ESC group (p&lt; 0.001).In the site of injury, several cavities were produced that disrupted portions of the gray and white matters. The extent of tissue damage was more severe in the sham and control groups than the other groups. Significantly more spinal tissue was spared in OEC and ESC groups (P &lt; 0.001). No significant difference in percentage of spared tissue was found between sham and control groups or transplanted groups. The percentage of myelinated area was greater in OEC group than in three other groups (p&lt; 0.05) (Figure 5, A). Although the percentage of myelinated area was more in ESC group in comparison with non-treated groups, but this difference was not significant.Conclusion: It seems that using of combination of a myelinating cells like OEC or schwann cell and source of cells to replace dead cells like Mesenchymal or embryonic stem cells, better results can be obtained due to probable synergic effects of these cells

Homing in hematopoietic stem cells: focus on regulatory role of CXCR7 on SDF1a/CXCR4 axis

Hematopoietic stem cells (HSCs) form a rare population of multipotent stem cells, which give rise to all hematopoietic lineages. HSCs home to bone marrow niches and circulate between blood and bone marrow. Many factors, especially SDF1a, affect the circulation of HSCs, but these have not been fully recognized. SDF1a has been shown to bind CXCR7 in addition to CXCR4 and can also function as SDF1a/CXCR4 modulator. CXCR7 plays a role in HSCs homing via SDF1a gradient and is a mediator of CXCR4/SDF1a axis. This review describes the current concepts and questions concerning CXCR7/CXCR4/SDF1a axis as an important key in hematopoietic stem cells homing with particular emphasis on CXCR7 receptor. Homing of HSCs is an essential step for successful hematopoietic stem cell transplantation