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Öğe Age-related changes in the immunomodulatory effects of human dental pulp derived mesenchymal stem cells on the CD4 + T cell subsets(2021) Özdemir, Rabia Bilge Özgül; Özdemir, Alper Tunga; Kırmaz, Cengiz; Sarıboyacı, Ayla Eker; Karaöz, Erdal; Erman, Gülay; Vatansever, H. Seda; Gökmen, Nihal MeteMesenchymal stem cells (MSCs) are powerful immunomodulatory cells. The effects of the aging on these abilities of MSCs have not been adequately clarified. In this study, alterations in immunomodulatory abilities of MSCs caused by aging were investigated. For this, dental pulp (DP) MSCs and peripheral blood mononuclear cells (PBMCs) of elderly and young donors were co-cultured age-matched and cross. We detected that the effects of DP-MSCs on Th1 and Th2 cells and their specific cytokines IFN-? and IL-4 are not affected by aging. However, we observed that young and elderly DP-MSCs have different effects on Th17 and Treg cells. Th17 frequencies of young and elderly PBMCs were significantly increased only by young DP-MSCs, in contrast, Treg frequencies were significantly increased by elderly DP-MSCs. IL-6, IL-17a and HGF levels of both young and elderly PBMCs showed a significant increase only by young DP-MSCs, but TGF-? levels were significantly increased only by elderly DP-MSCs. The oral cavity is home to a rich microflora. The interactions of dental tissues with this microflora can lead them to acquire different epigenetic modifications. Aging can affect the microflora composition of the oral cavity and change this process in different directions. According to our findings, DP-MSCs are effective cells in the regulation of CD4+ T cells, and their effects on Th1 and Th2 cells were not affected by aging. However, pleiotropic molecules IL-6 and HGF expressions, which are important in dental and bone tissue regeneration, decreased significantly in elderly DP-MSCs. This situation may have indirectly made a difference in the modulation effects of young and elderly DP-MSCs on the Th17 and Treg cells.Öğe Biohybrids for Combined Therapies of Skin Wounds: Agglomerates of Mesenchymal Stem Cells with Gelatin Hydrogel Beads Delivering Phages and Basic Fibroblast Growth Factor(Multidisciplinary Digital Publishing Institute (MDPI), 2024) Moghtader, Farzaneh; Tabata, Yasuhiko; Karaöz, ErdalThere is great interest in developing effective therapies for the treatment of skin wounds accompanied by deep tissue losses and severe infections. We have attempted to prepare biohybrids formed of agglomerates of mesenchymal stem cells (MSCs) with gelatin hydrogel beads (GEL beads) delivering bacteriophages (phages) as antibacterial agents and/or basic fibroblast growth factor (bFGF) for faster and better healing, providing combined therapies for these types of skin wounds. The gelatin beads were produced through a two-step process using basic and/or acidic gelatins with different isoelectric points. Escherichia coli (E. coli) and its specific T4 phages were propagated. Phages and/or bFGF were loaded within the GELs and their release rates and modes were obtained. The phage release from the basic GEL beads was quite fast; in contrast, the bFGF release from the acidic GEL beads was sustained, as anticipated. MSCs were isolated from mouse adipose tissues and 2D-cultured. Agglomerates of these MSCs with GEL beads were formed and maturated in 3D cultures, and their time-dependent changes were followed. In these 3D culture experiments, it was observed that the agglomerates with GEL beads were very healthy and the MSCs formed tissue-like structures in 7 days, while the MSC agglomerates were not healthy and shrunk considerably as a result of cell death.Öğe Calvarial bone defects in ovariectomised rats treated with mesenchymal stem cells and demineralised freeze-dried bone allografts(NLM (Medline), 2020) Kadiroğlu, Ela Tüleş; Akbalık, Mehmet Erdem; Karaöz, Erdal; Kanay, Berna Ersöz; Dağ, Ahmet; Ketani, Muzaffer Aydın; Eroğlu, E. G.; Uysal, Ersin; Tuncer, Cudi M.BACKGROUND: The aim of the study was to investigate the ability of a combination of bone marrow mesenchymal stem cells (BM-MSCs) with and without demineralised freeze-dried bone allografts (DFDBAs) to induce bone regeneration in calvarial defects in ovariectomised rats. MATERIALS AND METHODS: Critical size defects were filled with a combination of DFDBAs and BM-MSCs or BM-MSCs alone. Eight weeks after calvarial surgery, the rats were sacrificed. The samples were analysed histologically and immunohistochemically. RESULTS: No difference was observed in vascularisation between groups C1 (animals with cranial defect only, control group) and O1 (animals with cranial defect only, ovariectomy group). Intramembranous ossification was observed at a limited level in groups C2 (animals with cranial defect with MSCs, control group) and O2 (animals with cranial defect with MSCs, ovariectomy group) compared to C1 and O1. In group C3 (animals with DFDBAs with MSCs, control group), the fibrous structures of the matrix became compact as a result of a bone graft having been placed in the cavity, but in group O3 (animals with DFDBAs with MSCs, ovariectomy group), the fibrous tissue was poorly distributed between the bone grafts for the most parts. CONCLUSIONS: We conclude that the insertion of BM-MSCs enhances bone healing; however, the DFDBA/BM-MSC combination has little effect on overcoming impaired bone formation in ovariectomised rats.Öğe Can Wharton jelly derived or adipose tissue derived mesenchymal stem cell can be a treatment option for duchenne muscular dystrophy? answers as transcriptomic aspect(2020) Sun, Eda; Karaöz, ErdalIntroduction: Mesenchymal stem cells (MSCs) are able to differentiate into several cell lineages including skeletal muscle. In addition to their differentiation capacities, they have the ability to transfer their content genomic information horizontally through their exosomes and fusion abilities, as we have shown in our previous clinic study on Duchenne Muscular Dystrophy (DMD) patients, dystrophin expression increased after MSC treatment. Therefore, this study aimed to compare the transcriptomic properties of Wharton's jelly derived (WJ-) MSC and Adipose tissue (AT-) derived MSC, which are the two most preferred sources in MSC treatments applied in DMD. Methods: Both MSC cell lines obtained from ATCC (PCS-500-010; PCS-500-011) were characterized by flow cytometry then WJ-MSC and AT-MSC cell lines were sequenced via RNA-SEQ. R language was used to obtain the differentially expressed genes (DEGs) and differentially expressed miRNAs, respectively. Additionally, in order to support the results of our study, a gene expression profile data set of DMD patients (GSE1004) were acquired from Gene Expression Omnibus (GEO) database. Results: Here, we demonstrated that activated WNT signaling and downregulated TGF-? pathways under the control of decreased mir-24 which are involved in myogenic differentiation are differentially expressed in WJ-MSC. We have shown that the expression of mir-199a-5p, which is known to increase in exosomes of DMD patients, is less in WJ-MSC. Additionally, we have shown activated PI3K/Akt pathway, which is controlling mitochondria transfer via Tunnelling Nanotube as a new perspective in cellular therapies in myodegenerative diseases, in WJ-MSC more than in AT-MSCs. Conclusion: Summing up, WJ-MSC, which we recommend as an appropriate source candidate due to its immune-regulation properties, stands forward as a preferable source in the cellular treatment of DMD patients due to its transcriptomic aspect.Öğe Cardiovascular changes in WAG/Rij rats with genetic absence epilepsy: effects of chronic ethosuximide treatment(CUKUROVA UNIV, 2020) Şahin, Tuğçe Demirtaş; Utkan, Tijen; Karson, Ayşe; Yazir, Yusufhan; Karaöz, ErdalPurpose: The aim of this study was to investigate the effects of chronic ethosuximide (ETX) treatment on absence seizures and cardiovascular parameters in WAG/Rij rats with genetic absence epilepsy. Materials and Methods: Eight-weeks old, male Wistar and WAG/Rij rats were divided into four groups (n=20): Wistar control, Wistar ETX, WAG/Rij control and WAG/Rij ETX. ETX groups received chronic ETX treatment (oral, 300 mg/kg/day) for 3 months. At the end of the 3-month-treatment period; the total and mean duration, also number of spike wave discharges (SWDs) were evaluated using EEG recordings. Mean arterial blood pressure (MAP) and heart rate (HR) measurements were performed. Results: ETX treatment significantly decreased the duration and frequency of SWDs in WAG/Rij rats. MAP in WAG/Rij control group was markedly higher than Wistar control group. In Wistar ETX group, HR was significantly slower than Wistar control group. KCl-induced contraction response enhanced in Wistar ETX group and diminished in WAG/Rij control group compared to Wistar control group. Conclusion: Increased MAP and vascular reactivity in WAG/Rij rats. ETX treatment did not alter cardiovascular parameters in WAG/Rij rats whereas the treatment decreased the HR and vascular reactivity without affecting MAP in Wistar rats. T-type Ca++ channels may play a role in these changes.Öğe A case of non-progressive congenital myopathy: Efficacy and clinical outcomes of the wharton's jelly derived mesenchymal stem cell transplantation(Medical Sciences University of Teheran, 2022) Azeri, Rıza; Sun, Eda; Karaöz, ErdalNon-Progressive Congenital Myopathy is a disease characterized by muscle weakness, and unfortunately, there is no conventional treatment. In the last decade, regenerative medicine practices have become a rising value, and Mesenchymal Stem Cells (MSCs) have fascinating outcomes in regenerative medicine with their high regenerative capacities, their ability to regulate with paracrine secretions, and their immunological properties. Based on our experience in our previous clinical studies, Wharton's-Jelly-derived (WJ-)MSCs are the most suitable source for muscle diseases among all MSC sources. In this study, we evaluated the outcomes of 10 doses of WJ-MSC transplantation to the patient diagnosed with Non-Progressive Congenital Myopathy. A 17-year-old female with a SPEN-1 mutation, Non-Progressive Congenital Myopathy patient received 10 times as 1×10?/kg in the intra-arterial, intramuscular and intravenous administration of allogenic WJ-MSC. Before and after the treatment, the patient was followed-up with the upper extremity scale, Vignos lower extremity scale, muscle strength scale, functional independence measure, and evaluation of Serum creatine kinase (CK) levels. Improvement in both upper extremity scale and Vignos lower extremity scales, increasing in muscle strength, and decreasing in CK-level were detected. Although transplantation of WJ-MSC cannot treat any genetic-based diseases, they may benefit in alleviating clinical outcomes of disease. More importantly, WJ-MSC transplantation may offer a better quality of life by alleviating the symptoms of this rare disease with no treatment option that can be provided in conventional methods. © 2022 Tehran University of Medical Sciences. All rights reserved.Öğe Combination therapy using nanomaterials and stem cells to treat spinal cord injuries(Elsevier Science, 2022) Zarepour, Arezou; Bal Öztürk, Ayça; Koyuncu Irmak, Duygu; Yaşayan, Gökçen; Gökmen, Aylin; Karaöz, Erdal; Zarepour, Atefeh; Zarrabi, Ali; Mostafavi, EbrahimAs a part of the central nervous system, the spinal cord (SC) provides most of the communications between the brain and other parts of the body. Any damage to SC interrupts this communication, leading to serious problems, which may remain for the rest of their life. Due to its significant impact on patients’ quality of life and its exorbitant medical costs, SC injury (SCI) is known as one of the most challengeable diseases in the world. Thus, it is critical to introduce highly translatable therapeutic platforms for SCI treatment. So far, different strategies have been introduced, among which utilizing various types of stem cells is one of the most interesting ones. The capability of stem cells to differentiate into several types of cell lines makes them promising candidates for the regeneration of injured tissues. One of the other interesting and novel strategies for SCI treatment is the appli- cation of nanomaterials, which could appear as a carrier for therapeutic agents or as a platform for culturing the cells. Combining these two approaches, stem cells and nanomaterials, could provide promising therapeutic strategies for SCI management. Accordingly, in this review we have summarized some of the recent advance- ments in which the applications of different types of stem cells and nanomaterials, alone and in combination forms, were evaluated for SCI treatment.Öğe Combinations of wharton Jelly derived exosomes and salicylic acid: A new hope for eradication of cutaneous leishmaniasis(PARLAR SCIENTIFIC PUBLICATIONS, 2022) Köken, Gülnaz Yıldırım; Abamor, Emrah Şefik; Allahverdiyev, Adil; Karaöz, ErdalThe aim of the current study is to obtain wharton jelly derived exosomes, prepare therapeutic formulations including combinations of isolated exosomes and salicylic acid, investigate their in vitro antileishmanial activities against L.major promastigotes and amastigotes in order to develop a new alternative approach for recovery of Cutaneous Leishmaniasis. Exosomes isolated from mesenchymal stem cells were characterized by flow cytomeric analysis, zeta-sizer measurements and SEM visualization techniques. Following to demonstration of exosome existence, non-toxic concentrations of exosomes and salicylic acid were determined on L929 and J774 cells. The combined doses of exosomes and salicylic acid were applied on L.major promastigote and amastigote-macrophage culture by evaluation of various biological parameters of parasites such as viability, metabolic activity and infectivity. Obtained results indicate that combinations including non-toxic concentrations of exosome and salicylic acid displayed brilliant antileishmanial performances against each form of Leishmania parasites and this effect was too much bigger than use of these agents alone. We observed that combination applications substantially inhibited the viability and metabolic activity values of parasites and completely prevent the infection of macrophages with Leishmania promastigotes. These results reveal that exosome and salicylic acid combinations possessed significant inhibitory efficacies on L.major parasites. We foreseen that they would be further used in eradication of Cutaneous Leishmaniasis with a high success.Öğe Comparative analyses of immunosuppressive characteristics of bone-marrow, wharton's jelly, and adipose tissue-derived human mesenchymal stem cells(Galenos Yayincilik, 2017) Karaöz, Erdal; Demircan, Pınar Çetinalp; Erman, Gülay; Sun, Eda; Sarıboyacı, Ayla EkerObjective: Mesenchymal stem cells (MSCs), which possess immunosuppressive characteristics on induced T-cells, were shown to be applicable in prevention and treatment of graft-versus-host disease. However, knowledge of effective cell sources is still limited. In this study, MSCs from different human tissues, i.e. bone marrow (BM), Wharton's jelly (WJ), and adipose tissue, were isolated, and the immune suppression of stimulated T cells was analyzed comparatively. Materials and Methods: MSCs were co-cultured with phytohemagglutinin-induced T-cells with co-culture techniques with and without cell-to-cell contact. After co-culture for 24 and 96 h, the proliferation rate of T cells was estimated by carboxyfluorescein succinimidyl ester and apoptosis by annexin V/PI methods. Both T cells and MSCs were analyzed with respect to gene expressions by real-time polymerase chain reaction and their specific protein levels by ELISA. Results: The results showed that all three MSC lines significantly suppressed T-cell proliferation; BM-MSCs were most effective. Similarly, T-cell apoptosis was induced most strongly by BM-MSCs in indirect culture. In T cells, the genes in NFkB and tumor necrosis factor pathways were silenced and the caspase pathway was induced after co-culture. These results were confirmed with the measurement of protein levels, like transforming growth factor beta 1, IL-6, interferon-gamma, interleukin (IL)-2, and tumor necrosis factor-alpha. Additionally, IL-17A was detected in high levels in WJ-MSC co-cultures. We showed that IL-17A-producing Tregs are the key mediators in the treatment of graft-versus-host disease. Conclusion: BM-MSCs, which have been used in clinical applications for a while, showed the greatest immunosuppressive effect compared to other MSCs. However, a promising cell source could also be WJ, which is also effective in suppression with fewer ethical concerns. We described the molecular mechanism of WJ-MSCs in allogenic transplants for the first time.Öğe Comparative proteomics analysis of four commonly used methods for identification of novel plasma membrane proteins(Springer, 2019) Yöneten, Kübra Karaosmanoğlu; Kasap, Murat; Akpınar, Gürler; Kanlı, Aylin; Karaöz, ErdalPlasma membrane proteins perform a variety of important tasks in the cells. These tasks can be diverse as carrying nutrients across the plasma membrane, receiving chemical signals from outside the cell, translating them into intracellular action, and anchoring the cell in a particular location. When these crucial roles of plasma membrane proteins are considered, the need for their characterization becomes inevitable. Certain characteristics of plasma membrane proteins such as hydrophobicity, low solubility, and low abundance limit their detection by proteomic analyses. Here, we presented a comparative proteomics study in which the most commonly used plasma membrane protein enrichment methods were evaluated. The methods that were utilized include biotinylation, selective CyDye labeling, temperature-dependent phase partition, and density-gradient ultracentrifugation. Western blot analysis was performed to assess the level of plasma membrane protein enrichment using plasma membrane and cytoplasmic protein markers. Quantitative evaluation of the level of enrichment was performed by two-dimensional electrophoresis (2-DE) and benzyldimethyl-n-hexadecylammonium chloride/sodium dodecyl sulfate polyacrylamide gel electrophoresis (16-BAC/SDS-PAGE) from which the protein spots were cut and identified. Results from this study demonstrated that density-gradient ultracentrifugation method was superior when coupled with 16-BAC/SDS-PAGE. This work presents a valuable contribution and provides a future direction to the membrane sub-proteome research by evaluating commonly used methods for plasma membrane protein enrichment.Öğe Comparison of different sources of mesenchymal stem cells: palatal versus lipoaspirated adipose tissue(Karger, 2017) Hakkı, Sema S.; Turaç, Gizem; Bozkurt, S. Buket; Kayış, Seyit Ali; Hakkı, Erdoğan E.; Şahin, Eren; Subaşı Demir, Cansu; Karaöz, ErdalObjectives: The purpose of this study was to compare the proliferation and differentiation potential of mesenchymal stem cells (MSCs) derived from palatal adipose tissue (PAT) and lipoaspirated adipose tissue (LAT). Materials and Methods: PATs were obtained from 2 healthy female patients undergoing surgery for gingival recession, and LATs were obtained from 2 healthy female patients undergoing plastic surgery. LAT-and PAT-derived MSCs were confirmed by flow cytometry using MSC-specific surface markers. The multilineage differentiation capacity of the MSCs was analyzed. The expression of immunophenotyping, embryonic, and differentiation markers was compared between both MSC lines. The proliferation of PAT-and LAT-MSCs was evaluated using a real-time cell analyzer, and telomerase activity was determined using an ELISA-based TRAP assay. Stem cells isolated from PAT and LAT were analyzed by real-time PCR and whole genome array analysis. Results: The cells isolated from PAT had MSC characteristics. In addition, PAT-MSCs had significantly higher alkaline phosphatase activity and osteogenic potential than LAT-MSCs. Although the proliferation and telomerase activities of LAT-MSCs were higher than those of PAT-MSCs, the difference was not statistically significant. The level of embryonic stem cell markers (Oct4 and Nanog) was higher in LAT-MSCs than in PAT-MSCs. The whole genome array analysis demonstrated that 255 gene sequences were differentially expressed, with more than a twofold change in expression. Conclusions: This is the first comparative analysis of the isolation and characterization of MSCs from PAT and LAT. PAT is an accessible source of MSCs, which could be used in periodontal and craniofacial tissue engineering. (C) 2017 S. Karger AG, BaselÖğe Comparison of mesenchymal stem cell sheets and chondrocyte sheets in a rabbit growth plate injury model(Tubitak Scientific & Technical Research Council Turkey, 2020) Gültekin, Alper; Ağırdil, Yücel; Duman, Büşra Öncel; Subaşı Demir, Cansu; Karaöz, ErdalBackground/aim: The treatment of posttraumatic deformities and differences in length between the extremities resulting from physeal injury remains controversial. The aims of this study were to compare the efficacy of tissue-engineered, monolayer, and allogeneic mesenchymal stem cell sheets and chondrocyte sheets for physeal arrest treatment and to investigate cell sheet technology as a novel method for cell transplantation in physeal cartilage repair. Materials and methods: A proximal tibial physeal injury was induced in New Zealand rabbits. Allogeneic mesenchymal stem cells (MSCs) and chondrocytes were cultured in temperature-responsive culture dishes and applied to the iatrogenic partial growth plate defects in single-sheet grafts (cell sheets). Treatment efficacy was determined using radiological measurements, as well as histological and immunohistochemical staining. Results: Treatment with MSCs and chondrocytes prevented endochondral ossification in the physeal plate, and bone growth resumed after treatment in both the MSC and chondrocyte cell groups. We found significant differences in radiological evaluations between pre-and posttreatment measurements in both MSC and chondrocyte groups. Transplanted cells were observed in the damaged area in both of the groups, which differentiated in the direction of growth plate cartilage. Conclusion: Our results support the hypothesis that MSC or chondrocyte transplantation using the cell-sheet technique described in the present study aids in the regeneration of cartilage tissue during physeal arrest after growth plate damage.Öğe Comparison of similar cells: mesenchymal stromal cells and fibroblasts(Elsevier GmbH, 2020) Uğurlu, Burcu; Karaöz, ErdalAlmost from all organs, both mesenchymal stromal cells and fibroblasts can be isolated. Mesenchymal stromal cells (MSCs) are the most preferred cellular therapeutic agents with the regenerative potential, and fibroblasts are one of the most abundant cell types with the ability to maintain homeostasis. Because of the promising properties of MSCs, they have been well studied and their differentiation potentials, immunomodulatory potentials, gene expression profiles are identified. It has been observed that fibroblasts and mesenchymal stromal cells have similar morphology, gene expression patterns, surface markers, proliferation, differentiation, and immunomodulatory capacities. Thus, it is hard to distinguish these two cell types. Epigenetic signatures, i.e., methylation patterns of cells, are the only usable promising difference between them. Such significant similarities show that these two cells may be related to each other.Öğe Comparison of the effects of intratubal injection of adipose-derived mesenchymal stem cells in a rat sciatic nerve transection: an experimental study(Wolters Kluwer, 2021) Karakol, Perçin; Kapı, Emin; Karaöz, Erdal; Tunik, Selçuk; Bozkurt, MehmetThis study was designed to evaluate the efficacy of epineural tubulization (ENT) with or without intratubal application of adipose-derived mesenchymal stem cells (ASCs) in the rat model of sciatic nerve transection. After formation of 1-cm defect in the left sciatic nerve and ENT, 32 adults female Wistar albino rats were separated into 4 groups (n = 8 for each) including ENT per se (group 1; ENT group) and ENT plus intratubal ASC injection groups killed on day 21 (group 2; ENT-ASC-21-day group), 60 days (group 3; ENT-ASC-60-day group), and 120 days (group 4; ENT-ASC-120-day group). Functional (sciatic function index, hip circumference, withdrawal reflex latency, muscle weight ratio), electrophysiological, histomorphometric, and immunohistochemical analyses were performed in each group. Sciatic function index was significantly higher (?51.98 ± 5.94, P < 0.01) and withdrawal reflex latency was shorter (?6.21 ± 2.14, P < 0.01), in the group 4 as compared with all other groups on day 21. Amplitude of contraction was significantly lower in the group 4 as compared with all other groups (0.22 ± 0.05 vs 0.34 ± 0.07, 0.50 ± 0.11, and 0.61 ± 0.16, P < 0.01 for each). Immunohistochemical analysis revealed presence of green fluorescent protein, vimentin-stained cells, and single neural progenitor cells indicating that induction of neuronal differentiation by ASCs and direct involvement of ASCs within the axonal structure alongside extension of ASCs to the muscular layer of the group 4. In conclusion, our findings revealed that use of ENT plus intratubal ASC injection in a rat sciatic nerve transection model was associated with satisfactory functional outcome and improved peripheral axonal regeneration along with stem cell neural differentiation.Öğe Contribution of bone marrow–derived mesenchymal stem cells to healing of pulmonary contusion-created rats(Academic Press Inc., 2021) Demir, Sabri; Ertürk, Ahmet; Günal, Yasemin Dere; Özmen, İsmail; Zengin, Mehmet; Yıldız, Dinçer; Karaöz, Erdal; Karahan, Siyami; Şenel, EmrahBackground: The most common thoracic injury in children, resulting in trauma, is pulmonary contusion (PC). Bone marrow–derived mesenchymal stem cells (BM-MSCs) are used in wound healing and many other diseases. This study aims to examine the effects of BM-MSCs on PC healing in rats. Materials and methods: A total of 45 male Wistar albino rats were used. Four groups were formed. BM-MSCs were labeled with the green fluorescent protein. PC was observed in the control group. In group II, PC occured and left to spontaneous healing. In group III, PC formed and BM-MSCs were given. In group IV, BM-MSCs were given without PC formation. Subjects were sacrificed 1 week later. Whether there was any difference in terms of BM-MSC involvement and lung injury score was investigated. Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS), version 17.0, software (SPSS Inc., Chicago, IL), and p value of <0.05 was considered statistically significant. Results: BM-MSCs were collected much more in the lungs in group III than in group IV. Group III had a lower lung injury score value than group II. Conclusion: The greater involvement of the BM-MSCs in the injury site, and further reductions in lung injury score suggest that BM-MSCs are contributing to the healing of the injury. The use of BM-MSCs in risky patients with diffuse PC may be an alternative treatment to conventional methods.Öğe Determination of antibiotic impurities in good manufacturing practices-grade cell therapy medicinal products(Taylor & Francis Inc, 2020) Öztel, Olga Nehir; Korkmaz, Seval; Karaöz, ErdalBackrounds: According to the regulations of the health autorities, cell-based therapy products must be manufactured in good manufacturing production (GMP) facilities, fulfilling the required GMP standards. Products developed under the high quality control (QC) necessarity need to be approved for some QC tests. One of the main residual test is antibiotic test and this test should be validated. The aim of this study is to validate and determine the methods of detection of the antibiotic residue in the final product. Methods: Liquid Chromatography Tandem-Mass Spectrometry (LC-MS/MS) methods were used for the main steps of the production procedure, as well as the final products. Pharmaceutical Grade penicillin G and streptomycin sulfate were used as positive controls. Results: The results suggest that penicillin is broken down during cell culture and streptomycin is eliminated at the first washing step of the final product manufacture. It is shown in this study that LC-MS/MS method is one of the convenient method to test residual anibiotics and can be used to detect the antibiotic residues in cellular therapy products. Discussion: Since the antibiotic residues are eliminated in the final product and also it could be suggested that the methodology we followed is sufficiently safe and final product is pure.Öğe Differentiation potential and tumorigenic risk of rat bone marrow stem cells are affected by long-term in vitro expansion(Galenos Yayincilik, 2019) Karaöz, Erdal; Tepeköy Özçelik, FilizObjective: Mesenchymal stem cells (MSCs) have the capacity for extensive expansion and adipogenic, osteogenic, chondrogenic, myogenic, and neural differentiation in vitro. The aim of our study was to determine sternness, differentiation potential, telomerase activity, and ultrastructural characteristics of long-term cultured rat bone marrow (rBM)-MSCs. Materials and Methods: rBM-MSCs from passages 3, 50, and 100 (P3, P50, and P100) were evaluated through immunocytochemistry, reverse transcription-polymerase chain reaction, telomerase activity assays, and electron microscopy. Results: A dramatic reduction in the levels of myogenic markers actin and myogenin was detected in P100. Osteogenic markers Coln, osteonectin (Sparc), and osteocalcin as well as neural marker c-Fos and chondmgenic marker Coll2 were significantly reduced in P100 compared to P3 and P50. Osteogenic marker bone morphogenic protein-2 (BMP2) and adipogenic marker peroxisome proliferator-activated receptor gamma (Ppary) expression was reduced in late passages. The expression of sternness factor Rex-1 was lower in P100, whereas Oct4 expression was decreased in P50 compared to P3 and P100. Increased telomerase activity was observed in long-term cultured cells, signifying tumorigenic risk. Electron microscopic evaluations revealed ultrastructural changes such as smaller number of organelles and increased amount of autophagic vacuoles in the cytoplasm in long-term cultured rBM-MSCs. Conclusion: This study suggests that long-term culture of rBM-MSCs leads to changes in differentiation potential and increased tumorigenic risk.Öğe Effect of bone marrow and adipose tissue-derived mesenchymal stem cells on the natural course of corneal scarring after penetrating injury(Academic Press Ltd- Elsevier Science Ltd, 2016) Demirayak, Bengi; Yüksel, Nurşen; Çelik, Onur Sinan; Subaşı, Cansu; Duruksu, Gökhan; Ünal, Z. Seda; Yıldız, Demir Kürşat; Karaöz, ErdalIn the present study, we investigate and compare the efficacy of bone marrow- and adipose tissue-derived mesenchymal stem cell (MSCs) in corneal wound healing. A penetrating injury was created in the right corneas of Wistar rats (n = 40). Ten microliters of phosphate-buffered solution (PBS) containing 2 x 10(5) green fluorescent protein (GFP) labeled bone-marrow-derived MSCs to group 1 (n = 15), 10 mu l of PBS containing 2 x 10(5) GFP-labeled adipose-tissue-derived MSCs to group 2 (n = 15), 10 mu l PBS was injected into anterior chamber in group 3 (n = 10, control). Corneal opacity scoring, in vivo confocal microscopy, and histopathological evaluation were done at the end of 8 weeks. Immunofluorescence sections were evaluated to detect transplanted cells. Immune staining was performed to measure the expression levels of keratocan, aldehyde dehydrogenase (ALDH) and CD34. The gene expression levels of tumor necrosis factor (TNF-alpha), the interleukin 6 receptor (IL-6R), interleukin 12b (IL-12b), and transforming growth factor beta (TGF-beta 1) was measured on corneas. The establishment of stem cells in the corneas of the transplanted groups was confirmed by immunofluorescence staining. The expression of keratocan, ALDH, and CD34 increased in the transplanted groups (p < 0.05). The density of keratocytes increased significantly in both transplanted groups according to the in vivo confocal microscopy data (p < 0.05). The expression of TNF-alpha, IL-6R, and IL-12b decreased significantly in the transplanted groups (p < 0.05). Based on our findings, we consider that allogeneic stem cells facilitate the regeneration of corneal stroma and can be a cell source for stromal repopulation in diseased cornea. (C) 2016 Elsevier Ltd. All rights reserved.Öğe The effect of Korean red ginseng on mesenchymal stem cells from healthy and osteoporotic human bone marrow(2019) Kepekci, Ahmet Hamdi; Ergül, Zehragül; Gultekin, Alper; Karaöz, ErdalBackground: Osteoporosis is a disease characterized by an increase in bone fragility as a result of decreased bone mass and weakening of the bone structure. There are studies on the relationship between osteoporosis and hearing and balance system. The goal of this study was to compare the proliferation and osteogenesis induction properties of mesenchymal stem cells derived from healthy and osteoporotic individuals to better understand the healing properties of Korean red ginseng (KRG) and Panax ginseng-Avena Sativa-Tribulus Terrestris mixture (PAT). Materials and methods: Osteoporotic and healthy MSCs were isolated successfully in culture conditions. The proliferation levels of cells treated with different doses of KRG and PAT were compared by Water-Soluble Tetrazolium-1 (WST-1) assay. Alkaline phosphatase (ALP) assay was performed by selecting the most effective KRG dose in proliferation. Results: Morphology of isolated cells and the expression of cell surface antigens have been detected as similar. The WST-1 assay showed that KRG was effective on the proliferation of osteoporotic cells. The levels of ALP in osteoporotic cells treated with KRG is increased depending on the differentiation day compared to healthy cells. Conclusion: KRG triggered an increase in intracellular ALP levels of osteoporotic MSCs. It suggests that KRG on osteoporotic cells is influential in stimulating osteogenesis and may be useful in osteoporotic patients.Öğe The effect of mesenchymal stromal cells ın the microenvironment on cancer development(Springer, 2022) Özlem Sağlam-Uça; İrfan Değirmenci; Halbutoğulları, Zehra Seda; Posteki, Gökhan; Subaşı-Demirci, Cansu; Erman, Gülay; Karaöz, Erdal; Utkan, N. ZaferInfammatory signals secreted from the tumor microenvironment are thought to promote tumor growth and survival. It has been reported that stromal cells in the tumor microenvironment have similar characteristics to tumor-associated cells. In addition miRNAs play critical roles in various diseases, including cancer. In this study, we aimed to investigate the efects of co-culture of cancer cells and stromal cells isolated from normal and malignant breast tissue on each other and the possible efects of miRNAs on these interactions. The characterized stromal cells were co-cultured with an MDA-MB-231 cancer cell line. The proliferation capacity of the experimental groups was evaluated using the WST-1 assay. The expression of breast cancer-specifc miRNAs and related genes were assessed by real-time PCR. ELISA assay was performed to determine the concentration of some cytokines and chemokines. We found that the microenvironment plays an important role in the development of cancer, confrming the changes in the expression of oncogenic and tumor suppressor miRNA and their target genes after co-culture with malignant stromal cells. As a result of the studies, specifc gene expressions of related signaling pathways were detected in correlation with miRNA changes and the efects of tumor microenvironment on tumorigenesis were revealed in detail. miRNAs have been shown to play an important role in cancer development in recent studies. The idea that these small molecules can be used in diagnosis and treatment is becoming stronger day by day. We believe that new treatment approaches involving the tumor microenvironment and using miRNAs as markers are promising
