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  • Article: Evaluation of unrestricted somatic stem cells as a feeder layer to support undifferentiated embryonic stem cells.
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    ABSTRACT: The use of unrestricted somatic stem cells (USSCs) holds great promise for future clinical applications. Conventionally, mouse embryonic fibroblasts (MEFs) or other animal-based feeder layers are used to support embryonic stem cell (ESC) growth; the use of such feeder cells increases the risk of retroviral and other pathogenic infection in clinical trials. Implementation of a human-based feeder layer, such as hUSSCs that are isolated from human sources, lowers such risks. Isolated cord blood USSCs derived from various donors were used as a novel, supportive feeder layer for growth of C4mES cells (Royan C4 ESCs). Complete cellular characterization using immunocytochemical and flow cytometric methods were performed on murine ESCs (mESCs) and hUSSCs. mESCs cultured on hUSSCs showed similar cellular morphology and presented the same cell markers of undifferentiated mESC as would have been observed in mESCs grown on MEFs. Our data revealed these cells had negative expression of Stat3, Sox2, and Fgf4 genes while showing positive expression for Pou5f1, Nanog, Rex1, Brachyury, Lif, Lifr, Tert, B2m, and Bmp4 genes. Moreover, mESCs cultured on hUSSCs exhibited proven differentiation potential to germ cell layers showing normal karyotype. The major advantage of hUSSCs is their ability to be continuously cultured for at least 50 passages. We have also found that hUSSCs have the potential to provide ESC support from the early moments of isolation. Further study of hUSSC as a novel human feeder layer may lead to their incorporation into clinical methods, making them a vital part of the application of human ESCs in clinical cell therapy. Mol. Reprod. Dev. 79: 709-718, 2012. © 2012 Wiley Periodicals, Inc.
    Molecular Reproduction and Development 08/2012; 79(10):709-18. · 2.53 Impact Factor
  • Article: Constructing a hybrid molecule with low capacity of IgE binding from Chenopodium album pollen allergens.
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    ABSTRACT: Allergen specific immunotherapy is the only remedy to prevent the progression of allergic diseases. Nowadays, using of recombinant allergens with reduced IgE-binding capacity is an ideal tool for allergen immunotherapy. Therefore, in this study we focused on a hybrid molecule (HM) production with reduced IgE reactivity from Chenopodium album pollen allergens. By means of genetic engineering, a head to tail structure of the three allergens of the C. album pollen was designed. The resulting DNA construct coding for a 46kDa HM was inserted into an expression vector and expressed as hexahistidine tagged fusion protein in Escherichia coli. IgE reactivity of the HM was evaluated by western blotting, inhibition ELISA and in vivo skin prick test and its immunogenic property was tested by proliferation assay. The recombinant HM was expressed and purified by nickel-affinity chromatography. Comparison of the recombinant HM with a mixture of three recombinant allergens, as well as natural allergens in the whole C. album pollen extract via immunological experiments revealed that it has a much lower potential of IgE reactivity. Furthermore, in vivo skin prick tests showed that it has a significantly lower potency to induce cutaneous reactions than the mixture of recombinant wild type allergens and whole extract while, it had been preserved immunogenic properties. Our results have demonstrated that assembling three allergens of C. album in a hybrid molecule can reduce its IgE reactivity.
    Immunology letters 04/2012; 144(1-2):67-77. · 2.91 Impact Factor
  • Article: Amplification of antioxidant activity of haptoglobin(2-2)-hemoglobin at pathologic temperature and presence of antibiotics.
    Masoumeh Tayari, Danial Afsharzadeh
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    ABSTRACT: It is clear that Haptoglobin binds to Hemoglobin strongly and irreversibly. This binding, protects body tissues against heme-mediated oxidative tissue damages via peroxidase activity of Haptoglobin-Hemoglobin complex. Peroxidase activity of Haptoglobin(2-2)-Hemoglobin complex was determined via measurement of following increase in absorption of produced tetraguaiacol as the second substrate of Haptoglobin-Hemoglobin complex by UV-Vis spectrophotometer at 470 nm and 42°C. The results are showing that peroxidase activity of Haptoglobin(2-2)-Hemoglobin complex is modulated by homotropic effect of hydrogen peroxide as the allosteric substrate. On the other hand, antioxidant activity of Haptoglobin(2-2)-Hemoglobin is increased via heterotropic effect of two antibiotics (especially ampicillin) on the peroxidase activity of the complex. The condition of pathologic temperature along with the administration of ampicillin and/or coamoxiclav is in favor of amplification in antioxidant activity of Haptoglobin(2-2)-Hemoglobin and combating against free radicals in individuals with Hp2-2 phenotype. Therefore, oxidative stress effects have been diminished in the population with this phenotype.
    Indian Journal of Clinical Biochemistry 04/2012; 27(2):171-7.
  • Article: Diagnosis of Chenopodium album allergy with a cocktail of recombinant allergens as a tool for component-resolved diagnosis.
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    ABSTRACT: Chenopodium album pollen is one of the main sources of pollen allergy in desert and semi-desert areas and contains three identified allergens, so the aim of this study is comparison of the diagnostic potential of C. album recombinant allergens in an allergenic cocktail and C. album pollen extract. Diagnostic potential of the allergenic cocktail was investigated in 32 individuals using skin prick test and obtained results were compared with the acquired results from C. album pollen extract. Specific IgE reactivity against the pollen extract and allergenic cocktail was determined by ELISA and western blotting tests. Inhibition assays were performed for the allergenic cocktail characterization. The exact sensitization profile of all patients was identified which showed that 72, 81 and 46% of allergic patients had IgE reactivity to rChe a 1, rChe a 2 and rChe a 3, respectively. Almost all of C. album allergic patients (30/32) had specific IgE against the allergenic cocktail. In addition, there was a high correlation between IgE levels against the allergenic cocktail and IgE levels against the pollen extract. The allergenic cocktail was able to completely inhibit IgE binding to natural Che a 1, Che a 2 and Che a 3 in C. album extract. In addition, positive skin test reactions were seen in allergic patients that tested by the allergenic cocktail. The reliable results obtained from this study confirmed that the allergenic cocktail with high diagnostic potential could be replaced with natural C. album allergen extracts in skin prick test and serologic tests.
    Molecular Biology Reports 06/2011; 39(3):3169-78. · 2.93 Impact Factor

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