Characterization of growth and proliferation in a telomerase-immortalized ameloblastoma cell line / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To establish and characterize the cell line of ameloblastoma (AM) by transfection with human telomerase reverse transcriptase (hTERT).</p><p><b>METHODS</b>Primary cultures of AM cells were infected with a retroviral vector encoding hTERT. Infected cells were selected and checked by immunocytochemistry (ICC), in vitro proliferation, reverse transcriptase polymerase chain reaction (RT-PCR), senescence associated beta galactosidase staining (SA-beta-Gal staining), telomerase activity assay.</p><p><b>RESULTS</b>Compared to the uninfected cells, which arrested at the population doublings (PDL) of 6, the infected cells were more active in proliferation and reached 65 PDL to date. ICC confirmed the epithelial origin of the infected cells based on positive pan-cytokeratin and negative vimentin expression. There was no senescent signal in infected cells but not in uninfected cells. hTERT mRNA and telomerase activity were detected stably in infected cells.</p><p><b>CONCLUSIONS</b>The infected AM cells were immortalized after transfection with hTERT and can serve as a genetically defined model for AM study.</p>

Isolation, culture and identification of rat buccal mucosa stem cells / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To explore a method for isolation and culture Dispase II and Trypsin-EDTA. Cells were seeded onto mitomycin C-treated of rat buccal mucosa stem cells and to identify the stem cells.</p><p><b>METHODS</b>Epithelial cell mass were obtained by digesting rat buccal mucosa with 3T3 Swiss albino layer and cultured in DMEM for 24 hours, followed by K-SFM culturing. Some cells were induced to osteocytes and adipocytes and underwent ALP testing after 72 hours. Five days later, the primary cells were digested with trypsin and inoculated onto collagen IV-coated flasks and cultured at room temperature for 20 minutes. The adherent cells continued to be cultured with epithelial stem cell medium, then examined for identifying the clones, osteocytes, adipocytes, cytokeratin and ALP staining.</p><p><b>RESULTS</b>83.96 percent of the primary epithelial cell mass were in G0/G1 phase by flow cytometry test. The clones were seen after 72 hours on 3T3 Swiss albino layer, and the osteocytes and adipocytes were positive. Cells were adhered quickly to collagen IV, in a shape of round or orbicular-ovate with strong refraction. The induced-osteocyte and adipocyte, cytokeratin and ALP were all positive.</p><p><b>CONCLUSIONS</b>The stem cell-like epithelial cells could be obtain using the 3T3 Swiss albino layer method. Sieved by collagen IV and cultured in epithelial stem cell medium could make the epithelial stem cells depurate and proliferate quickly.</p>