Tehran University Medical Journal

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Background: Proteolytic enzymes, especially collagenases, are used for digestion of extracellular matrix, cell isolation and primary culture. Because of the problems in purification and low amount of collagenases in bacterial or animal sources, it is important to find new sources of the enzymes. So, in the present study actinidin, a plentiful protein in kiwifruit was purified and a mixture of actinidin and trypsin was applied to isolate rat aortic endothelial cells. Methods: Aortic endothelial cells were isolated using digestion solution containing different concentrations of actinidin (from 2 to 16 mg/ml) and trypsin (0.3, 0.6, 1.2 and 2.4 mg/ml) in different times (from 15 to 90 minute). Isolated cells were cultured in DMEM culture medium. Isolated cells were identified by morphological characteristics and immunocytochemical staining viability of separated cells was estimated by trypan blue exclusion test. Results: Actinidin in concentration of 10 mg/ml with trypsin in concentration of 1.2 mg/ml for one hour could isolate rat aortic endothelial cells. In this condition the viability of cells was estimated 90%. Morphological and immunocytochemical charac- teristics confirmed the isolated cells as endothelial cells. Conclusion: The results showed that the mentioned mixture of actinidin and trypsin has not considerable toxic effects on separated cells and is a novel and suitable option for isolation of rat aortic endothelial cells

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Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: Skin-derived precursors (SKPs) are a type of progenitor cells extracted from mammalian dermal tissue and can be differentiate to neural and mesodermal lineage in vitro. These cells can introduce an accessible autologos source of neural precursor cells for treatment of different neurodegenerative diseases. This research was done in order to set up isolation, culture, proliferation and differentiation of human skin derived precursors (hSKPs).
Methods: Human foreskin samples were cut into smaller pieces and cultured in proliferation medium after enzymatic digestion. To induce neural differentiation, cells were cultured in neural differentiation medium after fifth passage. We used immunocytochemistry and RT-PCR for characterization of the cells. Neuron and glial cell differentiation potential was assessed by immunofloresence using specific antibodies. The experiments were carried out in triplicate.
Results: After differentiation, βΙΙΙ- tubulin and neurofilament-M positive cells were observed that are specific markers for neurons. Moreover, glial fibrillary acid protein (GFAP) and S100 positive cells were identified that are markers specifically express in glial cells. Detected neurons and glials were also confirmed by their morphologic characterizations.
Conclusion: Our results demonstrated that skin-derived precursors obtained from human foreskin can exhibit neuronal and glial differentiation potential in vitro, depending on the protocols of induction.

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Background: Primary culture takes place following the cell isolation from tissues. Isolation and culture of melanocytes based on their roll in the protection of body against hazardous sun rays, production of skin, cornea and hair color is really important. This study was done to set isolation, culture and proliferation of melanocytes from children foreskin and adult eyelashes, and also comparison of two types of melanocyte culture medium.
Methods: Human foreskin and eyelash samples were used for melanocyte isolation and culture. After isolation of epidermis from dermis, epidermis cell suspensions were prepared by enzymatic digestion. The isolated cells were cultured in two melanocyte selective culture media. Immunocytochemistary and reverse transcription-polymerase chain reaction (RT-PCR) assays were used for confirmation of isolated and cultured melanocytes.
Results: Our results indicated that isolated melanocyte cultured in the selective medium without phorbol esters is better than the melanocytes cultured in selective medium cont-aining phorbol esters not only morphologically but also physiologically and from the aspect of cell adhesion. In addition, the results showed that isolated melanocyte from adult eyelashes are more dendritic than melanocytes isolated from children foreskin. Conversely, our results indicated that the number of cell passages in melanocyte isolat-ed from foreskin is more than melanocytes isolated from adult eyelashes.
Conclusion: Melanocytes cultured in selective medium containing convenient growth factors in absence of phorbol esters show more native physiological and adhesive properties. In addition, melanocyte isolated from younger tissues such as foreskin have better proliferative and sub-culturing properties so we suggest isolation and culture of younger tissues.