Phenotype-based primary screening for drugs promoting neuronal subtype differentiation in embryonic stem cells with light microscope / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To set up a platform for phenotype-based primary screening of drug candidates promoting neuronal subtype differentiation in embryonic stem cells (ES) with light microscope.</p><p><b>METHODS</b>Hanging drop culture 4-/4+ method was employed to harvest the cells around embryoid body (EB) at differentiation endpoint. Morphological evaluation for neuron-like cells was performed with light microscope. Axons for more than three times of the length of the cell body were considered as neuron-like cells. The compound(s) that promote neuron-like cells was further evaluated. Icariin (ICA, 10(-6)mol/L) and Isobavachin (IBA, 10(-7)mol/L) were selected to screen the differentiation-promoting activity on ES cells. Immunofluorescence staining with specific antibodies (ChAT, GABA) was used to evaluate the neuron subtypes.</p><p><b>RESULTS</b>The cells treated with IBA showed neuron-like phenotype, but the cells treated with ICA did not exhibit the morphological changes. ES cells treated with IBA was further confirmed to be cholinergic and GABAergic neurons.</p><p><b>CONCLUSION</b>Phenotypic screening with light microscope for molecules promoting neuronal differentiation is an effective method with advantages of less labor and material consuming and time saving, and false-positive results derived from immunofluorescence can be avoided. The method confirms that IBA is able to facilitate ES cells differentiating into neuronal cells, including cholinergic neurons and GABAergic neurons.</p>

Establishment of optimized neuronal differentiation-promoting model derived from P19 embryonic carcinoma cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To establish an optimized primary drug screen model of neuronal differentiation using P19 embryonal carcinoma cells.</p><p><b>METHODS</b>The final concentration of retinoid acid (RA), days of suspension culture, manner of adherent culture, suitable cell density and adherent culture medium were tested, respectively. Two stages of neuronal differentiation were examined based on morphological changes and immunocytochemistry analysis of neuronal specific protein β-tubulin III.</p><p><b>RESULTS</b>On d 8 of differentiation culture, neuron-like cells were observed with final concentration of 1 μmol/L RA. Neuron-like network was formed on d 16 of neuronal differentiation. β-tubulin III was positively stained on both stages, indicating P19 cells were differentiated into neurons.</p><p><b>CONCLUSION</b>The model using RA to induce P19 embryonic carcinoma cells to differentiate into neuron-like cells has been successfully established, which may provide a rapid, phenotypic cell-based platform for primary screening of neurogenesis-promoting drugs.</p>