Oxaloacetate as new inducer for osteogenic differentiation of human adipose tissue-derived mesenchymal stem cells in vitro.

BACKGROUND: Mitochondrial organelles play a crucial role in cellular metabolism so different cell types exhibit diverse metabolic and energy demands. Therefore, alternations in the intracellular distribution, quantity, function, and structure of mitochondria are required for stem cell differentiation. Finding an effective inducer capable of modulating mitochondrial activity is critical for the differentiation of specific stem cells into osteo-like cells for addressing issues related to osteogenic disorders. This study aimed to investigate the effect of oxaloacetate (OAA) on the osteogenic differentiation of human adipose-derived mesenchymal stem cells (hADSCs) in vitro. METHODS AND RESULTS: First, the most favorable OAA concentration was measured through MTT assay and subsequently confirmed using acridine orange staining. Human ADSCs were cultured in osteogenic medium supplemented with OAA and analyzed on days 7 and 14 of differentiation. Various assays including alkaline phosphatase assay (ALP), cellular calcium content assay, mineralized matrix staining with alizarin red, catalase (CAT) and superoxide dismutase (SOD) activity, and real-time RT-PCR analysis of three bone-specific markers (ALP, osteocalcin, and collagen type I) were conducted to characterize the differentiated cells. Following viability assessment, OAA at a concentration of 1 µM was considered the optimal dosage for further studies. The results of osteogenic differentiation assays showed that OAA at a concentration of 1 × 10- 6 M significantly increased ALP enzyme activity, mineralization, CAT and SOD activity and the expression of bone-specific genes in differentiated cells compared to control groups in vitro. CONCLUSIONS: In conclusion, the fundings from this study suggest that OAA possesses favorable properties that make it a potential candidate for application in medical bone regeneration.

Mesenchymal stem cells osteogenic differentiation by ZnO nanoparticles and polyurethane bimodal foam nanocomposites.

Mesenchymal stem cells with tissue repair capacity involve in regenerative medicine. MSCs can promote bone repair when employed with nano scaffolds/particles. Here, the MTT and Acridine Orange assay enabled the cytotoxic concentration of Zinc oxide nanoparticles and Polyurethane evaluation. Following culturing adipose tissue-derived MSCs, ADSCs' proliferation, growth, and osteogenic differentiation in the presence of PU with and without ZnO NPs is tracked by a series of biological assays, including Alkaline Phosphatase activity, Calcium deposition, alizarin red staining, RT-PCR, scanning electron microscope, and immunohistochemistry. The results showed boosted osteogenic differentiation of ADSCs in the presence of 1% PU scaffold and ZnO NPS and can thus apply as a new bone tissue engineering matrix. The expression level of Osteonectin, Osteocalcin, and Col1 increased in PU-ZnO 1% on the 7th and 14th days. There was an increase in the Runx2 gene expression on the 7th day of differentiation in PU-ZnO 1%, while it decreased on day 14th. In conclusion, Polyurethane nano scaffolds supported the MSCs' growth and rapid osteogenic differentiation. The PU-ZnO helps not only with cellular adhesion and proliferation but also with osteogenic differentiation.

Safety and immunogenicity of a recombinant receptor-binding domain-based protein subunit vaccine (Noora vaccine™) against COVID-19 in adults: A randomized, double-blind, placebo-controlled, Phase 1 trial.

The development of a safe and effective vaccine is essential to protect populations against coronavirus disease 2019 (COVID-19). There are several vaccine candidates under investigation with different mechanisms of action. In the present study, we have evaluated the safety and immunogenicity of a recombinant receptor-binding domain (RBD)-based protein subunit vaccine (Noora vaccine) against COVID-19 in adults. This Phase 1 trial is a randomized, double-blind, placebo-controlled study to evaluate the safety and immunogenicity of the recombinant RBD-based protein subunit vaccine (Noora vaccine) against COVID-19 in healthy adults volunteers. Eligible participants were included in this study after evaluating their health status and considering the exclusion criteria. They were then randomized into three groups and received three doses of vaccine (80 µg, 120 µg, and placebo) on Days 0, 21, and 35. Primary outcomes including solicited, unsolicited, and medically attended adverse events were recorded during this study. Secondary outcomes including the humoral and cellular immunity (including anti-RBD IgG antibody and neutralizing antibody) were measured on Days 0, 21, 28, 35, 42, and 49 by using the ELISA kit and the Virus Neutralization Test (VNT) was performed on day 49. Totally 70 cases were included in this Phase 1 trial and 60 of them completed the study. Safety assessments showed no severe adverse events. Local pain at the vaccine injection site occurred in 80% of the vaccinated volunteers. Induration and redness at the injection site were the other adverse reactions of this vaccine. There was no significant difference between the studied groups regarding adverse reactions. Anti-RBD IgG antibody and neutralizing antibody assessment showed significant seroconversion in comparison to the placebo group (80%, and 100% respectively, p < 0.001). The cellular immunity panel also showed mild to moderate induction of TH1 responses and the VNT showed 78% of seroprotection. The results of this Phase 1 trial showed acceptable safety without serious adverse events and significant seroconversions in the humoral and cellular immunity panel. The dose of 80 µg is an appropriate dose for injection in the next phases of the trial.

Staphylococcal enterotoxin B as DNA vaccine against breast cancer in a murine model.

Recently, many efforts have been made to treat cancer using recombinant bacterial toxins and this strategy has been used in clinical trials of various cancers. Therapeutic DNA cancer vaccines are now considered as a promising strategy to activate the immune system against cancer. Cancer vaccines could induce specific and long-lasting immune responses against tumors. This study aimed to evaluate the antitumor potency of the SEB DNA vaccine as a new antitumor candidate against breast tumors in vivo. To determine the effect of the SEB construct on inhibiting tumor cell growth in vivo, the synthetic SEB gene, subsequent codon optimization, and embedding the cleavage sites were sub-cloned to an expression vector. Then, SEB construct, SEB, and PBS were injected into the mice. After being vaccinated, 4T1 cancer cells were injected subcutaneously into the right flank of mice. Then, the cytokine levels of IL-4 and IFN-γ were estimated by the ELISA method to evaluate the antitumor activity. The spleen lymphocyte proliferation, tumor size, and survival time were assessed. The concentration of IFN-γ in the SEB-Vac group showed a significant increase compared to other groups. The production of IL-4 in the group that received the DNA vaccine did not change significantly compared to the control group. The lymphocyte proliferation increased significantly in the mice group that received SEB construct than PBS control group (p < 0.001). While there was a meaningful decrease in tumor size (p < 0.001), a significant increase in tumor tissue necrosis (p < 0.01) and also in survival time of the animal model receiving the recombinant construct was observed. The designed SEB gene construct can be a new model vaccine for breast cancer because it effectively induces necrosis and produces specific immune responses. This structure does not hurt normal cells and is a safer treatment than chemotherapy and radiation therapy. Its slow and long-term release gently stimulates the immune system and cellular memory. It could be applied as a new model for inducing apoptosis and antitumor immunity to treat cancer.

Schizophyllan promotes osteogenic differentiation of human adipose tissue-derived mesenchymal stem cells in vitro.

BACKGROUND: Bioactive polysaccharides are a promising way for bone disease prevention with high efficiency. Schizophyllan (SPG) is a polysaccharide derived from a species of fungus with anticancer, antitumor, and anti-inflammatory effects. In the present study, for the first time, the cell proliferation, osteogenic markers, mineral deposition, and osteogenic gene expression of human adipose tissue-derived mesenchymal stem cells (hADMSCs) grown on SPG were evaluated by in vitro assays. METHODS AND RESULTS: The cytotoxicity of SPG was measured using the MTT assay and acridine orange staining. Differentiation of hADMSCs was assessed using alkaline phosphatase (ALP) activity test, cellular calcium content assay, and mineralized matrix staining. To this end, Alizarin red S, von Kossa staining, and the expression of bone-specific markers, including ALP, Runx2, and osteonectin, were used by real-time RT-PCR over a 2-week period. According to the results, SPG at 10 µg/ml concentration was determined as the optimal dosage for differentiation studies. The results of osteogenic differentiation tests showed that compared to the control groups in vitro, SPG enhanced the osteogenic markers and mineralization as well as upregulation of the expression of bone specific genes in differentiated hADMSCs during differentiation. CONCLUSIONS: The results revealed that SPG could be applied as effective factor for osteogenic differentiation in the future. The current study provides insights into the hADMSC-based treatment and introduces promising therapeutic material for individuals who suffer from bone defects and injuries.

A new hydrogel with fluorapatite nanoparticles for osteogenic differentiation of human adipose-derived stem cells in tissue engineering field.

Since scaffolds are engineered to support functional tissue formation, their design and materials play an essential role in medical fields by providing different mechanical function. The aim of this study was to investigate the synthesis and structural characterization of collagen-gelatin (COL-GEL) composite scaffolds containing fluorapatite (FA) nanoparticles as well as evaluation of the osteogenic differentiation of human adipose-derived stem cells (hADSCs). First, the composite scaffolds were evaluated using Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction. The cytotoxicity of scaffolds and various concentrations of FA nanoparticles was studied through MTT assay and acridine orange/ethidium bromide staining. Next, the differentiated hADSCs were analyzed using Alizarin red and von Kossa staining, calcium content assay, alkaline phosphatase (ALP) activity, real-time RT-PCR, and immunocytochemical analyses. According to the characterization analyses, the composite scaffolds were properly integrated. The results also illustrated that COL-GEL composite scaffolds in the presence of FA nanoparticles not only showed no cytotoxicity but also increased ALP activity and calcium deposition as well as the expression of osteogenic genes, including Runx2, Col-I, ALP, and osteocalcin and the synthesis of proteins such as osteocalcin and osteopontin in vitro. The obtained data were confirmed by Alizarin red and von Kossa staining. These results are very promising for further tissue engineering experiments, in which FA nanoparticle incorporation into COL-GEL composite scaffolds is a novel approach that improves the surface COL-GEL composite scaffolds for tissue engineering application in vitro.

Neural Differentiation of Human-Induced Pluripotent Stem Cells (hiPSc) on Surface-Modified Nanofibrous Scaffolds Coated with Platelet-Rich Plasma.

The field of tissue engineering exploits living cells in a variety of ways to restore, maintain, or enhance tissues and organs. Between stem cells, human induced pluripotent stem cells (hiPSCs), are very important due to their wide abilities. Growth factors can support proliferation, differentiation, and migration of hiPSCs. Platelet-rich plasma (PRP) could be used as the source of growth factors for hiPSCs. In the present study, proliferation and neural differentiation of hiPSCs on surface-modified nanofibrous Poly-L-lactic acid (PLLA) coated with platelet-rich plasma was investigated. The results of in vitro analysis showed that on the surface, which was modified nanofibrous scaffolds coated with platelet-rich plasma, significantly enhanced hiPSCs proliferation and neural differentiation were observed. Whereas the MTT ([3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide]) results showed biocompatibility of surface-modified nanofibrous scaffolds coated with platelet-rich plasma and the usage of these modified nanoscaffolds in neural tissue engineering in vivo is promising for the future.

Evaluation of antioxidant and antibacterial effects of lactobacilli metabolites- preconditioned bone marrow mesenchymal stem cells in skin lesions amelioration.

BACKGROUND AND OBJECTIVES: Mesenchymal stem cells (MSCs) therapeutically intensify wound-healing. Meanwhile, probiotics are capable to inhibit pathogenic bacteria by secreting antimicrobial and antioxidant agents. They ameliorate more the wounds, by MSCs' synergistic effect. METHODS AND RESULTS: This way, MSCs exposed to probiotics metabolites (the extracts of Lactobacillus plantarum and Lactobacillus casei), become more viable, and the optimum doses of probiotics metabolites were determined by Trypan blue and MTT assays. Then, preconditioned MSCs (pre-MSCs) faced again the oxidative stress (100 µM H2O2), and their survival rate was assessed by MTT assay. Conditioned medium (CM) prepared from pre-MSCs and the expression rate of antioxidant proteins evaluated by Real-time PCR. The antimicrobial activity of the samples was evaluated using the MIC method. Then mice wound models were treated with the mixture of a basal ointment and each CM of pre-MSCs. The proliferation and viability of MSCs improved by the probiotic's metabolites preconditioning (P ≤ 0.05). pre-MSCs exhibited significant up-regulated in antioxidant genes expression (P ≤ 0.001). Also, probiotics metabolites presented a significant free radical scavenging effect (P ≤ 0.001). CMs of pre-MSCs showed considerably increased antibacterial activity (P ≤ 0.05). Experimental groups compared with the controls revealed that wound contraction was more rapid in groups that received CMs of LP-MSCs, LC-MSCs, MSCs, and then finally mixed probiotics metabolites, respectively. CONCLUSIONS: These results provide a novel insight into the probiotics extract effect on the improvement of MSCs' potential for wound healing procedures.

Anti-apoptotic effect of Nisin as a prebiotic on human mesenchymal stem cells in harsh condition.

Mesenchymal stem cells (MSCs) are progenitor cells of connective tissue with the ability of proliferation, self-renewal, and multilineage differentiation that make it a promising source with an enormous potential to be utilized for tissue repairing and vehicles of cell-based gene therapy. The low survival rate of MSCs following transplantation is their drawback. Preconditioning with some factors is a novel and effective strategy, improving the survival of the cells by protecting them from harmful conditions and result in the good recovery of injured tissues. Nisin is a prebiotic with antimicrobial activity. This manuscript aimed to evaluate the effect of Nisin preconditioning of MSCs on in vitro cell viability. MSCs were cultured and preconditioned with Nisin in different concentrations. Then, they are separately exposed to H2O2 and serum deprivation. Cell survival and cell apoptosis were evaluated by MTT assay and Real-time PCR, respectively. Furthermore, Annexin-PI staining and caspase activity was performed to visualize apoptotic cells. MSC-Nisin viability and proliferation significantly increased when exposed to H2O2 and serum deprivation, compared to that of MSCs. About 250 and 500 IU/mL of Nisin donate a significant anti-apoptotic impact to MSCs. Our data suggest that preconditioning with Nisin has been improved cell viability and the anti-apoptotic capacity of MSCs. However, the mechanism related to the protective properties of preconditioning and using this strategy in stem cell therapy requires more research.

Safety of grafting acellular human corneal lenticule seeded with Wharton's Jelly-Derived Mesenchymal Stem Cells in an experimental animal model.

The present study was conducted to evaluate safety of grafting acellular human corneal lenticule seeded with Wharton's Jelly-derived Mesenchymal Stem Cells (WJSC) in an experimental animal model. Human corneal lenticules were decellularized with a rate of about 97% with an acceptable lack of cytotoxicity and relatively intact ultrastructure of the lenticules. 12 rabbits underwent unilateral stromal pocketing with implantation of decellularized lenticules. Implantation was performed for 6 rabbits along with graft recellularization with WJSCs. Rabbits were euthanized after 1 month (n = 6) and 3 months (n = 6) to evaluate progression of graft bio-integration. No clinical rejection sign was detected during the study. Histopathological analysis showed that, grafts were integrated well with the least distortion of surrounding collagen bundles. After 3 months, labeled WJCS was detected representing viability of stem cells in the host. Increased expression of keratocyte-specific markers showed the potential of recruiting WJSCs as keratocyte progenitor cells to reinforce corneal ultrastructure.

Laboratory methods to decipher epigenetic signatures: a comparative review.

Epigenetics refers to nucleotide sequence-independent events, and heritable changes, including DNA methylation and histone modification (as the two main processes), contributing to the phenotypic features of the cell. Both genetics and epigenetics contribute to determining the outcome of regulatory gene expression systems. Indeed, the flexibility of epigenetic effects and stability of genetic coding lead to gene regulation complexity in response signals. Since some epigenetic changes are significant in abnormalities such as cancers and neurodegenerative diseases, the initial changes, dynamic and reversible properties, and diagnostic potential of epigenomic phenomena are subject to epigenome-wide association studies (EWAS) for therapeutic aims. Based on recent studies, methodological developments are necessary to improve epigenetic research. As a result, several methods have been developed to explore epigenetic alterations at low, medium, and high scales, focusing on DNA methylation and histone modification detection. In this research field, bisulfite-, enzyme sensitivity- and antibody specificity-based techniques are used for DNA methylation, whereas histone modifications are gained based on antibody recognition. This review provides a mechanism-based understanding and comparative overview of the most common techniques for detecting the status of epigenetic effects, including DNA methylation and histone modifications, for applicable approaches from low- to high-throughput scales.

Well-Orientation Strategy for Direct Immobilization of Antibodies: Development of the Immunosensor Using the Boronic Acid-Modified Magnetic Graphene Nanoribbons for Ultrasensitive Detection of Lymphoma Cancer Cells.

This work presents an effective strategy for the well-oriented immobilization of antibodies in which boronic acid is directly attached to the surface and with no need of the long and flexible spacer. A magnetic graphene nanoribbon-boronic-acid-based immunosensor was developed and tested for the impedimetric detection of lymphoma cancer cells, a blood cancer biomarker. Magnetic graphene nanoribbons (MGNRs) were modified with boronic acid (BA) to create a supporting matrix that is utilized by immobilizing anti-CD20 antibodies with good orientation. The prepared biosensing layer (MGNR/BA/Ab) with well-oriented antibodies was premixed into whole blood samples to interact with lymphoma cancer cell receptors. In the presence of target cell receptors, an immunocomplex was formed between anti-CD20 antibodies and lymphoma cancer cell receptors. Then, the biosensing layer was magnetically collected on a screen-printed carbon electrode (SPCE) and placed in a homemade electrochemical cell configuration to measure impedimetric signals. The fabrication steps of the immunosensor were characterized by various techniques, such as resonance light scattering, fluorescence, electrochemical impedance spectroscopy, and cyclic voltammetry. The assay is highly sensitive: the calculated limit of detection of lymphoma cancer cells was as low as 38 cells/mL, and the detection was linear from 100 to 1 000 000 cells/mL. The specificity of the immunosensor is also very high, and there is no interference effect with several potential interferents, such as the breast cancer (MCF-7), human embryonic kidney (HEK293), and leukemia (HL-60 and KCL-22) cell lines. The performance of the immunosensor for lymphoma cancer cells in clinical blood samples is consistent with that of commercial flow cytometric assays.

A comparative study of hBM-MSCs' differentiation toward osteogenic lineage in the presence of progesterone and estrogen hormones separately and concurrently in vitro.

Promising cell sources for tissue engineering comprise bone marrow derived-mesenchymal stem cells (BM-MSCs) that have multiple differentiation potentials. Also, sex hormones act as important elements in bone development and maintenance, and the roles of two female sex steroid hormones known as estrogen (17-ß estradiol) and progesterone in osteogenic differentiation of human BM-MSCs (hBM-MSCs) are studied. For this purpose, hBM-MSCs were treated with a 1 × 10-6 M concentration of 17-ß estradiol and progesterone separately and simultaneously while the optimum concentrations were obtained by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Osteogenic differentiation tests including measurement of alkaline phosphatase (ALP) enzyme activity, the content of total mineral calcium, mineralized matrix staining by Alizarin Red and Von Kossa solutions, real-time reverse transcription polymerase chain reaction (RT-PCR), and immunofluorescence staining were carried out on Days 7 and 14 of differentiation. To exhibit the morphology of the cells, the BM-MSCs were stained with acridine orange (AO) solution. In this study, the results of ALP activity assay, calcium content and real-time RT-PCR assay and also all tests of differentiation staining have shown that 17-ß estradiol has been recognized as an enhancing factor of osteogenic differentiation. Furthermore, MTT assay and AO staining revealed progesterone as a factor that seriously improved the proliferation of hBM-MSCs. Generally, the 17-ß estradiol individually or in the presence of progesterone has more effects on BM-MSCs' osteogenic differentiation compared to progesterone alone. In this study, it is indicated that the effect of the 17-ß estradiol and progesterone concurrently was the same as individual 17-ß estradiol on the differentiation of hBM-MSCs.

The effect of female sex steroid hormones on osteogenic differentiation of endometrial stem cells.

Bone regeneration is a significant and crucial health issue worldwide. Tissue bioengineering has shown itself to be the best substitute for common clinical treatment of bone loss. The suitable cell source is human endometrial stem cells (hEnSCs) which have several suitable characteristics for this approach. Since sex steroid hormones are involved in expansion and conservation of the skeleton, the effect of two sex steroid hormones known as estrogen (17-ß estradiol) and progesterone on osteogenic differentiation of hEnSCs were examined. For this purpose, hEnSCs were treated with 17-ß estradiol and progesterone separately (1 × 10-6 M) and simultaneously (1 × 10-7 M). Osteogenic differentiation tests including measurement of total mineral calcium content, Alizarin Red staining, the quantitative expression levels of some osteogenic markers by Real-time RT-PCR, and immunofluorescence staining were performed at 7 and 14 days of differentiation. To exhibit the morphology of the cells in osteogenic and culture medium, the hEnSCs were stained with Acridine Orange (AO) solution. In this research, MTT assay and AO staining revealed progesterone and 17-ß estradiol increase the proliferation of hEnSCs in a dose-dependent manner. Furthermore, the results of calcium content analysis, Real-time RT-PCR assay, and all tests of differentiation staining have shown that 17-ß estradiol and progesterone cannot induce hEnSCs' osteogenic differentiation. In conclusion, it is indicated that 17-ß estradiol and progesterone do not have positive effects on hEnSCs' osteogenic differentiation in vitro.

The role of inflammation and its related microRNAs in breast cancer: A narrative review.

Breast cancer is recognized as the most common type of cancer among women with a high rate of mortality all over the world. Over the past years, growing attention has been regarded to realize more about the mechanisms underlying the disease process. It is revealed that the progression of breast cancer may be strongly linked to chronic inflammation owing to the role of inflammatory factors in genetic instability and subsequent cancer predisposition. Although the association between breast cancer and inflammatory pathways has been well-defined now, only recent evidence pointed towards the inflammation-related microRNAs (miRNAs) as potential biomarkers and therapeutic targets involved in the crosstalk of multiple pathways during breast cancer development. Moreover, the practical interactions between these miRNAs and inflammatory factors are also a little characterized. In this review, we intended to describe the effects of predominant inflammatory pathways such as cytokines, phosphoinositide 3-kinase/protein kinase B, and nuclear factor kappa B in association with tumor promoting and tumor suppressing miRNAs on breast cancer progression. Providing new studies in the field of combining biomarkers for early diagnosis, prognosis, and monitoring breast cancer are very important. Notably, understanding the underlying mechanisms of miRNAs as a possible link between inflammation and tumorigenesis may offer a novel insight for combating this epidemic.

Antimicrobial effects of mesenchymal stem cells primed by modified LPS on bacterial clearance in sepsis.

BACKGROUND AND OBJECTIVES: Mesenchymal stem cells (MSCs)-based regenerative therapy is now considered as an alternative approach to revive infectious diseases, including sepsis. Nevertheless, the efficiency of MSC application is limited by the poor survival rate of engrafted MSCs. Hence, preconditioning was established as a strategy to increase the cells' efficiency. METHODS: MSCs were preconditioned with 1 µg/ml of three different lipopolysaccharides (LPSs) of Pseudomonas (Pse-LPS), Acinetobacter (Ac-LPS), and Acinetobacter inactivated lipid A by PagL (Ac-LPS-PagL). Then, preconditioned MSCs were exposed to oxidative stress and serum deprivation followed by evaluation of the antibacterial activity, survival, and apoptosis of MSCs. Then, the murine sepsis model treated with 100 µl phosphate-buffered saline (control group, sepsis group), 100 µl of 1 × 10 6 wild MSCs (MSC group), and three remained groups received 100 µl of 1 × 10 6 LPS-preconditioned MSCs (Pse-LPS-MSCs group: LPS purified from Pseudomonas, or Ac-LPS-MSCs group: LPS purified from Acinetobacter, and Ac-PagL-LPS-MSCs group: detoxified LPS Pagl). RESULTS: After 4 days, LPS-preconditioned MSC transplantation modulated the immune response and reduced inflammation in septic mice. Apoptosis of Pse-LPS/Ac-LPS-preconditioned-MSCs was obviously reduced in vitro, and the survival rate of engrafted mice was evidently elevated in Pse-LPS-MSCs and Ac-LPS-MSCs groups compared with other three groups. CONCLUSION: LPS preconditioning provides an innovative strategy for evolving functional and biological properties of MSCs and ameliorates the survival rate of the mouse model of sepsis after MSC transplantation, protects cells from apoptosis and organ damages, and evaluates therapeutic properties, including immunemodulatory.

Osteogenic differentiation of preconditioned bone marrow mesenchymal stem cells with lipopolysaccharide on modified poly-l-lactic-acid nanofibers.

Tissue engineering is an interdisciplinary expertise that involves the use of nanoscaffolds for repairing, modifying, and removing tissue defects and formation of new tissues. Mesenchymal stem cells (MSCs) can differentiate into a variety of cell types, and they are attractive candidates for tissue engineering. In the current study, the electrospinning process was used for nanofiber preparation, based on a poly-l-lactic-acid (PLLA) polymer. The surface was treated with O 2 plasma to enhance hydrophilicity, cell attachment, growth, and differentiation potential. The nanoscaffolds were preconditioned with lipopolysaccharide (LPS) to enhance induction of differentiation. The nanoscaffolds were categorized by contact angle measurements and scanning electron microscopy. The MTT assay was used to analyze the rate of growth and proliferation of cells. Osteogenic differentiation of cultured MSCs was evaluated on nanofibers using common osteogenic markers, such as alkaline phosphatase activity, calcium mineral deposition, quantitative real-time polymerase chain reaction, and immunocytochemical analysis. Based on the in vitro results, primed MSCs with LPS on the PLLA nanoscaffold significantly enhanced the proliferation and osteogenesis of MSCs. Also, the combination of LPS and electrospun nanofibers can provide a new and suitable matrix to support stem cells' differentiation for bone tissue engineering.

Mesenchymal stem cells preconditioned by staphylococcal enterotoxin B enhance survival and bacterial clearance in murine sepsis model.

Sepsis, a health-threatening progressive infectious disease, is the major cause of morbidity and mortality worldwide. Cell therapy using mesenchymal stromal cells (MSCs) is an innovative strategy with excessive therapeutic potential in the treatment of sepsis. Staphylococcal enterotoxin B (SEB) preconditioning aims to prolong the interval of survival of transplanted MSCs which induces the production of cytoprotective agents, anti-apoptotic and anti-inflammatory factors. The MSCs were preconditioned with an optimum dose of SEB (470 µmol/L). The expression levels of apoptosis genes and antibacterial activity of MSC and SEB-MSC and their conditioned medium (CM), as well as cell survival, were studied in vitro in an oxidative stress and serum deprivation condition. Following treatment of the septic mice with MSCs and SEB-MSCs, pro/anti-inflammatory cytokines, hematological factors, bacterial clearance and animal survival were assessed. The apoptotic and pro-inflammatory cytokine's genes expression was down-regulated while antibacterial peptides and anti-inflammatory cytokines were up-regulated in SEB-MSC-treated mice. The animal survival rates were improved; bacterial clearance was enhanced in the peritoneal fluids, blood and organs; aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were reduced in blood, compared with saline and MSCs alone. This research concludes that transplantation of SEB-MSCs presents improved therapeutic effects on a live bacterial model of sepsis.

Nisin, a potent bacteriocin and anti-bacterial peptide, attenuates expression of metastatic genes in colorectal cancer cell lines.

Colorectal cancer is the third most common cause of cancer-related death in the world which genetic and environmental agents are responsible for cancer. When cells detach from the tumor and invade surrounding tissues, the tumor is malignant and may form secondary tumors at other locations in a process called metastasis. Probiotics are the largest group of inhabitation bacteria in the colon. Gut microbiota has a central role in prevented the risk colon cancer. Probiotics are beneficial microorganisms, like Lactic acid bacteria and Lactobacilli bacteria which are using in the dairy industry. Probiotics nisin are having the most important category of safe usage. In this study LS180, SW48, HT29 and Caco2 was cultured and treated with different dose of nisin. Cell proliferation was assayed with MTT. The expression of CEA, CEAM6 and MMP2F genes was analyzed with Real-time PCR. Protein expression of CEA was evacuated with ELISA. Our result was shown that the 40-50 IU/mL nisin could suppress proliferation of LS180. Cell proliferation of SW48, HT29, Caco2 cells was decreased in 250-350 IU/mL concentration of nisin. The gene expression of CEA, CEAM6, MMP2F was significantly down-regulated with nisin treatment (p < 0.001, p < 0.01). Also, after cells treated with nisin, CEA protein expression was down regulated (p < 0.01). In conclusion, nisin could suppressed metastatic process via down-regulation of CEA, CEAM6, MMP2F, MMP9F genes. We suggested the new treatment strategies beyond Probiotics, which play a role in the prevention local tumor invasion, metastasis and recurrence.

Manufacturing of a novel double-function ssDNA aptamer for sensitive diagnosis and efficient neutralization of SEA.

Staphylococcal enterotoxin A (SEA) is an enterotoxin produced mainly by Staphylococcus aureus. In recent years, it has become the most prevalent compound for staphylococcal food poisoning (SFP) around the world. In this study, we isolate new dual-function single-stranded DNA (ssDNA) aptamers by using some new methods, such as the Taguchi method, by focusing on the detection and neutralization of SEA enterotoxin in food and clinical samples. For the asymmetric polymerase chain reaction (PCR) optimization of each round of systematic evolution of ligands by exponential enrichment (SELEX), we use Taguchi L9 orthogonal arrays, and the aptamer mobility shift assay (AMSA) is used for initial evaluation of the protein-DNA interactions on the last SELEX round. In our investigation the dissociation constant (KD) value and the limit of detection (LOD) of the candidate aptamer were found to be 8.5 ±â€¯0.91 of nM and 5 ng/ml using surface plasmon resonance (SPR). In the current study, the Taguchi and mobility shift assay methods were innovatively harnessed to improve the selection process and evaluate the protein-aptamer interactions. To the best of our knowledge, this is the first report on employing these two methods in aptamer technology especially against bacterial toxin.