ABSTRACT
A countrywide study over the eras indicates overuse of blood transfusion can have considerable risks to patients accompanied by significant costs of blood transfusion for patients, hospitals, and health-care systems. Besides, more than 30% of the world's population is anemic. Typically, blood transfusion helps continue suitable oxygen transfer in anemia, i.e., more and more documented as a threatening factor with several adverse outcomes including long hospitalization, morbidity, and mortality. Transplantation of allogeneic blood is thus like a two-edged sword. There is no doubt that the blood transfusion is a life-saving treatment, but it should be underpinned by much of up-to-date health-care services. The new theory considered for patient blood management (PBM) also discusses the timely application of evidence-based surgical and clinical theories and focuses on patient outcomes. Furthermore, PBM involves a multidisciplinary methodology to reduce unnecessary transfusions, minimize costs, and cut risks.
ABSTRACT
BACKGROUND: Over the past few years, mesenchymal stromal cells (MSCs) have attracted a great deal of scientific attention owing to their promising results in the treatment of incurable diseases. However, there are several concerns about their possible side effects after direct cell transplantation, including host immune response, time-consuming cell culture procedures, and the dependence of cell quality on the donor, which limit the application of MSCs in clinical trials. On the other hand, it is well accepted that the beneficial effects of MSCs are mediated by secretome rather than cell replacement. MSC secretome refers to a variety of bioactive molecules involved in different biological processes, specifically neuro-regeneration. MAIN BODY: Due to the limited ability of the central nervous system to compensate for neuronal loss and relieve disease progress, mesenchymal stem cell products may be used as a potential cure for central nervous system disorders. In the present study, the therapeutic effects of MSC secretome were reviewed and discussed the possible mechanisms in the three most prevalent central nervous system disorders, namely Alzheimer's disease, multiple sclerosis, and Parkinson's disease. The current work aimed to help discover new medicine for the mentioned complications. CONCLUSION: The use of MSC-derived secretomes in the treatment of the mentioned diseases has encouraging results, so it can be considered as a treatment option for which no treatment has been introduced so far.
Subject(s)
Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Neurodegenerative Diseases , Parkinson Disease , Humans , Neurodegenerative Diseases/therapy , Secretome , Mesenchymal Stem Cell Transplantation/methodsABSTRACT
PURPOSE: Fisetin (FIS) is a natural flavonoid with anti-proliferative and anti-apoptotic effects on different human cancer cell lines and can be considered a therapeutic agent for ALL treatment. However, FIS has little aqueous solubility and bioavailability, limiting its therapeutic applications. Thus, novel drug delivery systems are needed to improve solubility and bioavailability of FIS. Plant-derived nanoparticles (PDNPs) could be considered a great delivery system for FIS to the target tissues. In this study, we investigated the anti-proliferative and anti-apoptotic effect of free FIS and FIS-loaded Grape-derived Nanoparticles (GDN) FIS-GDN in MOLT-4 cells. MATERIALS/METHODS: In this study, MOLT-4 cells were treated with increasing concentration of FIS and FIS-GDN and viability of cells were assessed by MTT assay. Additionally, cellular apoptosis rate and related genes expression were evaluated using flow cytometry and Real Time-PCR methods, respectively. RESULTS: FIS and FIS-GDN decreased cells viability and increased cells apoptosis dose-dependently, but not time dependently. Treatment of MOLT-4 cells with increasing concentrations of FIS and FIS-GDN considerably increased the expression of caspase 3, 8 and 9 and Bax level, and also decreased the expression of Bcl-2. Results indicated an increased apoptosis after increased concentration of FIS and FIS-GDN at 24, 48 and 72 h. CONCLUSIONS: Our data proposed that FIS and FIS-GDN can induce apoptosis and have antitumor properties in MOLT-4 cells. Furthermore, compared to FIS, FIS-GDN induced more apoptosis in these cells by increasing the solubility and efficiency of FIS. Additionally, GDNs increased FIS effectiveness in proliferation inhibition and apoptosis induction.
Subject(s)
Nanoparticles , Vitis , Humans , Flavonols/pharmacology , Flavonoids/pharmacology , Apoptosis , Cell Line, TumorABSTRACT
Chronic lung diseases, such as chronic obstructive pulmonary disease (COPD) and asthma, are one of the most frequent causes of morbidity and mortality in the global. COPD is characterized by progressive loss of lung function through inflammation, apoptosis, and oxidative stress caused by chronic exposure to harmful environmental pollutants. Airway inflammation and epithelial remodeling are also two main characteristics of asthma. In spite of extensive efforts from researchers, there is still a great need for novel therapeutic approaches for treatment of these conditions. Accumulating evidence suggests the potential role of mesenchymal stem cells (MSCs) in treatment of many lung injuries due to their beneficial features including immunomodulation and tissue regeneration. Besides, the therapeutic advantages of MSCs are chiefly related to their paracrine functions such as releasing extracellular vesicles (EVs). EVs comprising exosomes and microvesicles are heterogeneous bilayer membrane structures loaded with various lipids, nucleic acids and proteins. Due to their lower immunogenicity, tumorigenicity, and easier management, EVs have appeared as favorable alternatives to stem cell therapies. Therefore, in this review, we provided an overview on the current understanding of the importance of MSCs and MSC-derived EVs from different sources reported in preclinical and clinical COPD and asthmatic models.
Subject(s)
Asthma , Extracellular Vesicles , Mesenchymal Stem Cells , Pulmonary Disease, Chronic Obstructive , Asthma/therapy , Extracellular Vesicles/metabolism , Humans , Inflammation/metabolism , Mesenchymal Stem Cells/metabolism , Pulmonary Disease, Chronic Obstructive/therapyABSTRACT
Bone marrow mesenchymal stromal cells (MSCs) play a crucial role in the regulation of hematopoiesis. These cells affect the process through direct cell-cell contact, as well as releasing various trophic factors and extracellular vehicles (EVs) into the bone marrow microenvironment. MSC-derived EVs (MSC-EVs) are prominent intercellular communication tolls enriched with broad-spectrum bioactive factors such as proteins, cytokines, lipids, miRNAs, and siRNAs. They mimic some effects of MSCs by direct fusion with hematopoietic stem cells (HSC) membranes in the bone marrow (BM), thereby affecting HSC fate. MSC-EVs are attractive scope in cell-free therapy because of their unique capacity to repair BM tissue and regulate proliferation and differentiation of HSCs. These vesicles modulate the immune system responses and inhibit graft-versus-host disease following hematopoietic stem cell transplantation (HSCT). Recent studies have demonstrated that MSC-EVs play an influential role in the BM niches because of their unprecedented capacity to regulate HSC fate. Therefore, the existing paper intends to speculate upon the preconditioned MSC-EVs as a novel approach in HSCT.
Subject(s)
Extracellular Vesicles , Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Extracellular Vesicles/metabolism , Graft vs Host Disease/metabolism , Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cells/metabolism , Humans , Mesenchymal Stem Cell Transplantation/adverse effects , Mesenchymal Stem Cells/metabolismABSTRACT
Purpose: Insoluble fibronectin as an extracellular matrix (ECM) protein has the potential to promote proliferation, differentiation, and migration of mesenchymal stem cells (MSCs). However, there is limited information about the effects of fibronectin various concentrations on bone marrow-derived MSCs (BMMSCs) function and differentiation. Methods: In this experimental study, using a gel injection device, BMMSCs were encapsulated in sodium alginate microcapsules containing 1.25% alginate, 1% gelatin, and fibronectin (0.01, 0.05, 0.1, and 0.2 µg/ml). MTT assay was used to examine the proliferation of BMMSCs. Also, BMMSCs apoptosis were analyzed using Annexin-V/PI staining and fluorescence activated cell sorting (FACS). Alkaline phosphatase (ALP) test was conducted to assess BMMSCs osteogenic differentiation potential. Finally, mRNA expression levels of the SP7, osteocalcin (OCN), Twist Family BHLH Transcription Factor 1 (Twist1), Peroxisome proliferator-activated receptor γ2 (PPARγ2), Cyclin-dependent kinase 1 (CDK1), and Zinc Finger and BTB Domain Containing 16 (ZBTB16), following exposure with fibronectin 0.1 µg/ml. Results: According to results, fibronectin had the potential to promote proliferation rates of the BMMSCs, in particular at 0.1 and 0.2 µg/ml concentrations. we showed that the fibronectin was not able to modify apoptosis rates of the BMMSCs. ALP test results approved the notable potential of the fibronectin, to trigger osteogenic differentiation of the BMMSCs. Also, RT-PCR results indicated that fibronectin 0.1 µg/ml could augment osteogenic differentiation of cultured BMMSCs through targeting of OCN, SP7, Twist1, CDK1, and ZBTB16, strongly or slightly. Conclusion: Results showed that fibronectin can improve proliferation and osteogenic differentiation of BMMSCs without any effect on these cells' survival.
ABSTRACT
Natural killer cells (NK cells) are innate immune cells that are activated to fight tumor cells and virus-infected cells. NK cells also play an important role in the graft versus leukemia response. However, they can over-develop inflammatory reactions by secreting inflammatory cytokines and increasing Th1 differentiation, eventually leading to tissue damage. Today, researchers have attributed some autoimmune diseases and GVHD to NK cells. On the other hand, it has been shown that mesenchymal stem cells (MSCs) can modulate the activity of NK cells, while some researchers have shown that NK cells can cause MSCs to lysis. Therefore, we considered it is necessary to investigate the effect of these two cells and their signaling pathway in contact with each other, also their clinical applications.
Subject(s)
Immunomodulation , Mesenchymal Stem Cells , Cell Differentiation , Cytokines/metabolism , Killer Cells, NaturalABSTRACT
Regulatory T cells (Tregs) have the role of regulating self-tolerance, and suppressing immune responses. Defects in Treg function and number can lead to in loss of tolerance or autoimmune disease. To treat or control autoimmune diseases, one of the options is to develop immune tolerance for Tregs cell therapy, which includes promotion and activation. Recently, cell-based treatment as a promising approach to increase cells function and number has been developed. Cell therapy by chimeric T antigen receptor (CAR-T) cells has shown significant efficacy in the treatment of leukemia, which has led researchers to use CAR-T cells in other diseases like autoimmune diseases. Here, we describe the existing treatments for autoimmune diseases and the available treatments based on Treg, their benefits and restrictions for implementation in clinical trials. We also discussed potential solutions to overcome these limitations. It seems novel designs of CARs to be new hope for autoimmune diseases and expected to be a potential cure option in a wide array of disease in the future. Therefore, it is very important to address this issue and increase information about it.
Subject(s)
Autoimmune Diseases/therapy , Immunotherapy/methods , Receptors, Chimeric Antigen/immunology , T-Lymphocytes, Regulatory/immunology , Animals , Autoimmune Diseases/immunology , HumansABSTRACT
Many studies have been performed about regenerative and immunomodulatory properties of mesenchymal stem cells (MSCs) and their application in different treatment approaches. The present study aimed to investigate the immunomodulatory effect of umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) on the gene expression profile of cytokines in stimulated T-lymphocytes. For this purpose, MSCs were isolated from umbilical cord blood samples and cultured in Dulbecco's Modified Eagle Medium supplemented with 10% fetal bovine serum. The nature of MSCs was identified by flow cytometry analysis and differentiation to the adipocyte and osteocyte lineage. Moreover, to investigate the immunomodulatory effects of MSCs on T cells, a co-culture system was designed and expression levels of interleukin (IL)-2, IL-4, IL-6, IL-10, IL-13, interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and transforming growth factor-beta (TGF-ß) genes were measured; using the real-time polymerase chain reaction (RT-PCR) technique. Our results demonstrated the ability of MSCs to differentiate into adipocyte and osteocyte lineages. Further investigation also displayed that although UCB-MSCs could significantly reduce the expression of pro-inflammatory cytokines like IL-2, IL-6, IFN-γ, and TNF-α in activated T-lymphocytes, they noticeably potentiated the expression levels of IL-4, IL-10, IL-13, and TGF-ß in the co-culture setting. In conclusion, UCB-MSCs have immunomodulatory effects on activated T-lymphocytes in favor of anti-inflammatory responses.
Subject(s)
Cytokines/immunology , Fetal Blood/immunology , Immunomodulation , Lymphocyte Activation/immunology , Mesenchymal Stem Cells/immunology , T-Lymphocytes/immunology , Humans , Inflammation/immunologyABSTRACT
Umbilical cord Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) have recently gained considerable attention in the field of regenerative medicine. Their high proliferation rate, differentiation ability into various cell lineages, easy collection procedure, immuno-privileged status, nontumorigenic properties along with minor ethical issues make them an ideal approach for tissue repair. Besides, the number of WJ-MSCs in the umbilical cord samples is high as compared to other sources. Because of these properties, WJ-MSCs have rapidly advanced into clinical trials for the treatment of a wide range of disorders. Therefore, this paper summarized the current preclinical and clinical studies performed to investigate the regenerative potential of WJ-MSCs in neural, myocardial, skin, liver, kidney, cartilage, bone, muscle, and other tissue injuries.
Subject(s)
Mesenchymal Stem Cells/cytology , Stem Cell Transplantation , Umbilical Cord/cytology , Wharton Jelly/cytology , Cell Differentiation/physiology , Cell Proliferation/physiology , Humans , Stem Cell Transplantation/methodsABSTRACT
Purpose: Mesenchymal stem cells (MSCs) release hematopoietic cytokines, growth factors, and Microvesicles (MVs) supporting the hematopoietic stem cells (HSCs). MVs released from various cells, playing a crucial role in biological functions of their parental cells. MSC-derived MVs contain microRNAs and proteins with key roles in the regulation of hematopoiesis. Umbilical cord blood (UCB) is a source for transplantation but the long-term recovery of platelets is a main problem. Therefore, we intend to show that MSC-MVs are able to improve the differentiation of UCB-derived CD34+ cells to megakaryocyte lineage. Methods: In this descriptive study, MSCs were cultured in DMEM to collect the culture supernatant, which was ultracentrifuged for the isolation of MVs. HSCs were isolated from UCB using MACS method and cultured in IMDM supplemented with cytokines and MVs in three different conditions. Megakaryocyte differentiation was evaluated through the expression of specific markers and genes after 72 hours, and the data was analyzed by t test (P<0.05). Results: The expression of specific megakaryocyte markers (CD41 and CD61) in the presence of different concentrations of MSC-MVs did not show any significant difference. Also, the expression of specific genes of megakaryocyte lineage was compared with control group. The expression of GATA2 and c-Mpl was significantly increased, GATA1 was not significantly decreased, and FLI1 was significantly decreased. Conclusion: MSC-MVs could improve the expression of specific megakaryocyte genes; however, there was no significant expression of CD markers. Further studies, including the evaluation of late stages of megakaryocyte differentiation, are required to evaluate platelet production and shedding.
ABSTRACT
All cells encounter various signals coming from the surrounding environment and they need to receive and respond to these signals in order to perform their functions. Cell surface receptors are responsible for signal transduction .Platelets are blood cells which perform several functions using diverse receptors. Platelet concentrate is one of the most consumed blood products. However, due to the short lifespan of the platelets and platelets damage during storage, we face shortage of platelet products. One of the damages that platelets undergo during storage is the loss of surface receptors. Since cell surface receptors are responsible for all cell functions, the loss of platelet receptors reduces the quality of platelet products. In this study, we reviewed the important receptors involved in platelet activation and their associated signaling pathways. We also looked at the platelet receptors that shed during storage and the causes of this incident. We found that GPIbα, P-selectin, CD40 and GPVI are platelet receptors that fall during platelet storage at room temperature. Considering that GPVI and GPIbα are the most important receptors which involved in platelet activation, their shedding can cause decrease in platelet activation after transfusion and decrease thrombus consistence. Shear stress and platelet contact with the container wall are among the mechanisms discussed in this process, but studies in this area have to be continued.
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Purpose: Mesenchymal stem cells (MSCs) play an important role in the proliferation and differentiation of hematopoietic stem cells (HSCs) in the bone marrow via cell-to-cell contact, as well as secretion of cytokines and microvesicles (MVs). In this study, we investigated the effect of mesenchymal stem cell-derived microvesicles (MSC-MVs) on erythroid differentiation of umbilical cord blood-derived CD34+ cells. Methods: In this descriptive study, CD34+ cells were cultured with mixture of SCF (10 ng/ml) and rhEPO (5 U/ml) cytokines in complete IMDM medium as positive control group. Then, in MV1- and MV2-groups, microvesicles at 10 and 20 µg/ml concentration were added. After 72 hours, erythroid specific markers (CD71 and CD235a) and genes (HBG1, GATA1, FOG1 and NFE2) were assessed by flow cytometry and qRT-PCR, respectively. Results: The expression of specific markers of the erythroid lineages (CD71 and GPA) in the presence of different concentration of microvesicles were lower than that of the control group (P<0.001). Also, the expression of specific genes of the erythroid lineages (NFE2, FOG1, GATA1, and HBG1) was investigated in comparison to the internal control (GAPDH). Among all of them, HBG1 and FOG1 genes were significantly decreased to the control group (P<0.0001) but GATA1 and NFE2 gene expressions was not significant. Conclusion: The results of this study showed that MSC-MVs decrease the erythroid differentiation of umbilical cord blood-derived CD34+ cells. Therefore, MSC-MVs play a key role in the regulation of normal erythropoiesis.
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OBJECTIVES: Angiogenesis, the process of formation of new blood vessels, is essential for development of solid tumors. At first, it was first assumed that angiogenesis is not implicated in the development of acute myeloid leukemia (AML) as a liquid tumor. One of the most important elements in bone marrow microenvironment is mesenchymal stem cells (MSCs). These cells possess an intrinsic tropism for sites of tumor in various types of cancers and have an impact on solid tumors growth by affecting the angiogenic process. But so far, our knowledge is limited about MSCs' role in liquid tumors angiogenesis. By increasing our knowledge about the role of MSCs on angiogenesis, new therapeutic strategies can be used to improve the status of patients with leukemia. MATERIALS AND METHODS: In this experimental study, HL-60, K562 and U937 cells were separately co-cultured with bone marrow derived-MSCs and after 8, 16 and 24 hours, alterations in the expression of 10 chemokine genes involved in angiogenesis, were evaluated by quantitative real time-polymerase chain reaction (qRT-PCR). Mono-cultures of leukemia cell lines were used as controls. RESULTS: We observed that in HL-60 and K562 cells co-cultured with MSCs, the expression of CXCL10 and CXCL3 genes are increased, respectively as compared to the control cells. Also, in U937 cells co-cultured with MSCs, the expression of CXCL6 gene was upgraded. Moreover in U937 cells, CCL2 gene expression in the first 16 hours was lower than the control cells, while within 24 hours its expression augmented. CONCLUSIONS: Our observations, for the first time, demonstrated that bone marrow (BM)-MSCs are able to alter the expression profile of chemokine genes involved in angiogenesis, in acute myeloid leukemia cell lines. MSCs cause different effects on angiogenesis in different leukemia cell lines; in some cases, MSCs promote angiogenesis, and in others, inhibit it.
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OBJECTIVE: Mesenchymal stem cells (MSCs) are multipotent stromal cells that can differentiate into a variety of cell types. They control the process of hematopoiesis by secreting regulatory cytokines and growth factors and by the expression of important cell adhesion molecules for cell-to-cell interactions. This investigation was intended to examine the effect of bone marrow (BM)-derived MSCs on the differentiation of HL-60 cells according to morphological evaluation, flow cytometry analysis, and gene expression profile. MATERIALS AND METHODS: The BM-MSCs were cultured in Dulbecco's modified Eagle's medium supplemented with 10% fetal bovine serum (FBS). After the third passage, the BM-MSCs were irradiated at 30 Gy. To compare how the HL-60 cells differentiated in groups treated differently, HL-60 cells were cultured in RPMI-1640 and supplemented with 10% FBS. The HL-60 cells were seeded into six-well culture plates and treated with all-trans-retinoic acid (ATRA), BM-MSCs, or BM-MSCs in combination with ATRA, while one well remained as untreated HL-60 cells. The expression levels of the granulocyte subset-specific genes in the HL-60 cells were assayed by real-time polymerase chain reaction. RESULTS: Our results revealed that BM-MSCs support the granulocytic differentiation of the human promyelocytic leukemia cell line HL-60. CONCLUSION: Based on the results of this study, we concluded that BM-MSCs may be an effective resource in reducing or even preventing ATRA's side effects and may promote differentiation for short medication periods. Though BM-MSCs are effective resources, more complementary studies are necessary to improve this differentiation mechanism in clinical cases.
Subject(s)
Cell Communication , Cell Differentiation , Granulocytes/metabolism , HL-60 Cells/metabolism , Mesenchymal Stem Cells/metabolism , Biomarkers , Cell Differentiation/drug effects , Coculture Techniques , Granulocytes/cytology , HL-60 Cells/drug effects , Humans , Immunohistochemistry , Immunophenotyping , Tretinoin/pharmacologyABSTRACT
Understanding the role of toll-like receptors (TLRs) in the immunomodulation potential, differentiation, migration, and survival of mesenchymal stem cells (MSCs) is absolutely vital to fully exploiting their MSC-based therapeutic potential. Furthermore, through recognition of exogenous or endogenous ligands produced upon injury, TLRs have been linked to allograft rejection and maintenance of chronic inflammatory diseases, including Crohn's disease, rheumatoid arthritis. Characterizing the effect of TLRs in biological control of MSCs fate and function could improve our knowledge about the MSC-based cell therapy and immunotherapy. In this paper, we outline the impacts of TLR activation and mechanisms on MSCs immunomodulatory functions, differentiation, migration, and survivability. Moreover, we indicate that the expression patterns of TLRs in MSCs from different sources.
Subject(s)
Cell Differentiation/physiology , Mesenchymal Stem Cells/physiology , Toll-Like Receptors/physiology , Adipogenesis/physiology , Animals , Apoptosis/physiology , Cell Lineage , Cell Movement/physiology , Chondrogenesis/physiology , Endosomes/physiology , Humans , Immune System/physiology , Inflammation/physiopathology , Mice , Organ Specificity , Osteogenesis/physiology , Pathogen-Associated Molecular Pattern MoleculesABSTRACT
Hematopoietic stem cells (HSCs) are multipotent stem cells, with self-renewal ability as well as ability to generate all blood cells. Mesenchymal stem cells (MSCs) are multipotent stem cells, with self-renewal ability, and capable of differentiating into a variety of cell types. MSCs have supporting effects on hematopoiesis; through direct intercellular communications as well as secreting cytokines, chemokines, and extracellular vesicles (EVs). Recent investigations demonstrated that some biological functions and effects of MSCs are mediated by their EVs. MSC-EVs are the cell membrane and endosomal membrane compartments, which are important mediators in the intercellular communications. MSC-EVs contain some of the molecules such as proteins, mRNA, siRNA, and miRNA from their parental cells. MSC-EVs are able to inhibit tumor, repair damaged tissue, and modulate immune system responses. MSC-EVs compared to their parental cells, may have the specific safety advantages such as the lower potential to trigger immune system responses and limited side effects. Recently some studies demonstrated the effect of MSC-EVs on the expansion, differentiation, and clinical applications of HSCs such as improvement of hematopoietic stem cell transplantation (HSCT) and inhibition of graft versus host disease (GVHD). HSCT may be the only therapeutic choice for patients who suffer from malignant and non-malignant hematological disorders. However, there are several severe side eï¬ects such GVHD that restricts the successfulness of HSCT. In this review, we will discuss the most important effects of MSCs and MSC-EVs on the improvement of HSCT, inhibition and treatment of GVHD, as well as, on the expansion of HSCs.
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Mesenchymal stromal/stem cells (MSCs) are involved in tissue homeostasis through direct cell-to-cell interaction, as well as secretion of soluble factors. Exosomes are the sort of soluble biological mediators that obtained from MSCs cultured media in vitro. MSC-derived exosomes (MSC-DEs) which produced under physiological or pathological conditions are central mediators of intercellular communications by conveying proteins, lipids, mRNAs, siRNA, ribosomal RNAs and miRNAs to the neighbor or distant cells. MSC-DEs have been tested in various disease models, and the results have revealed that their functions are similar to those of MSCs. They have the supportive functions in organisms such as repairing tissue damages, suppressing inflammatory responses, and modulating the immune system. MSC-DEs are of great interest in the scope of regenerative medicine because of their unique capacity to the regeneration of the damaged tissues, and the present paper aims to introduce MSC-DEs as a novel hope in cell-free therapy.
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Human serum albumin (HSA) is a non-glycosylated, negatively charged protein (Mw: about 65-kDa) that has one free cystein residue (Cys 34), and 17 disulfide bridges that these bridges have main role in its stability and longer biological life-time (15 to 19 days). As HSA is a multifunctional protein, it can also bind to other molecules and ions in addition to its role in maintaining colloidal osmotic pressure (COP) in various diseases. In critical illnesses changes in the level of albumin between the intravascular and extravascular compartments and the decrease in its serum concentration need to be compensated using exogenous albumin; but as the size of HSA is an important parameter in retention within the circulation, therefore increasing its molecular size and hydrodynamic radius of HSA by covalent attachment of poly ethylene glycol (PEG), that is known as PEGylation, provides HSA as a superior volume expander that not only can prevent the interstitial edema but also can reduce the infusion frequency. This review focuses on various PEGylation methods of HSA (solid phase and liquid phase), and compares various methods to purifiy and characterize the pegylated form.