Publications (3)10.14 Total impact
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Article: Differentiation of human embryonic stem cell-derived retinal progenitors into retinal cells by Sonic hedgehog and/or retinal pigmented epithelium and transplantation into the subretinal space of sodium iodate-injected rabbits.
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ABSTRACT: Transplantation of retinal cells has recently provided a promising therapeutic approach for retinal degeneration. Here, we differentiated initially retinal progenitors (RPs) from adherent feeder-free human embryonic stem cells (hESCs) with the use of defined media supplemented with a specific combination of growth factors. The differentiated RPs highly (>80%) expressed related molecular features that included Six3 at an early stage in addition to Crx, Rx, Pax6, Otx2, and Chx10 at later stage. Next, we examined the induction of photoreceptors by Shh and/or the coculture of rabbit retinal pigmented epithelium with hESCs-derived RPs. The differentiation of retinal cells was demonstrated by protein and gene expression in all groups. However, S-Opsin, a cone photoreceptor marker, had higher expression in the presence of Shh, whereas expressions of Gli and Hes1 decreased in the same group. Finally, hESC-derived RPs were treated with Shh transplanted into the subretinal space of sodium iodate-injected albino-type adult rabbits and analyzed 4 weeks later. Transplanted retinal cells survived, migrated into retinal layers, and restored a small but significant B-wave. The grafted cells expressed photoreceptor markers, S-Opsin and Rhodopsin. Our results indicate that putative hESC-derived retinal cells express related genes and proteins. Further, our results show that retinal-like cells can be useful replacements for photoreceptors in retinal diseases.Stem cells and development 04/2011; 21(1):42-53. · 4.15 Impact Factor -
Article: Neural induction in mouse embryonic stem cells by co-culturing with chicken somites.
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ABSTRACT: The role of paraxial mesoderm or the somites in decision of ectoderm to acquire the neuroepithelial fate and its subsequent diversification to functional neural subtypes especially in mammalians is obscure. Here we report, for the first time, the influence of the co-culture of alginate bead-encapsulated somites isolated from chick embryos on neural differentiation in mouse embryonic stem cells-derived embryoid bodies (EBs). Using a combination of morphology, immunofluorescence, flow cytometry, semiquantitative, and conventional RT-PCR techniques, we show that the somites induce rosette structures and weakly enhance neural differentiation and neural markers in a dose-dependent manner in comparison to the control group, but its effect is lower than retinoic acid treatment of EBs. By liquid chromatography-mass spectrometry, it was revealed that somitic cells synthesized and released retinoids into the medium. However, no effective influence of somitic co-culture on rostrocaudal or dorsoventral patterning is seen. Therefore, like amphibians, somites have a modest neural-inducing activity in amniotes.Stem cells and development 06/2009; 18(9):1351-60. · 4.15 Impact Factor -
Article: Sperm MTT viability assay: a new method for evaluation of human sperm viability.
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ABSTRACT: MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay is commonly used as a cell proliferation assay. The objective of this study was to evaluate the capability of MTT assay to discriminate between viable and nonviable sperms and compare it sefficiency with E&N (eosin and nigrosin) and HOST (hypo-osmotic swelling test). MTT assay was modified to obtain optimal result for assessment of sperm viability. After standardization of method, MTT, E&N, and HOST were carried out simultaneously on 57 semen samples from patients referring to Isfahan Fertility and Infertility Center. The correlation coefficient between these tests and sperm motility was calculated using the SPSS statistical program. Specificity and sensitivity of each test was also obtained. The optimal conditions for sperm MTT viability assay were 2 h after addition of sperm to MTT in HAM'S F10 + 25 mM HEPES + 10% HSA at 37 degrees C and pH 7.4-7.45. Inter- and intra-assay coefficients of variations were 9 and 7%, respectively. The sensitivity and specificity for sperm MTT viability assay, E&N, and HOST were 97,98, and 99%, and 100, 100, and 83% respectively. High significant correlations were obtained between sperm MTT viability assay, E&N, HOST and motility. Sperm MTT viability assay can be used as a diagnostic test for discrimination of viable sperms from sperm population.Journal of Assisted Reproduction and Genetics 10/2002; 19(10):477-82. · 1.84 Impact Factor
