OBJECTIVE: To analysis the proliferation properties and telomerase activity of human embryonic tendon cells transformed by ptsA58H plasmid cultured in vitro continuously. METHODS: The 40th, 70th, and 75th passages of transformed human embryonic tendon cells (THETC) were adopted. The collagen secretion of THETC was detected by immunohistochemical methods, the growth curve of different passages of THETC was compared, and chromosome karyotype was analyzed. Total RNA of THETC were extracted to detect human telomerase reverse transcriptase (hTERT) mRNA expression by RT-PCR technique. RESULTS: When THETC were subcultured to 70 passages, the morphological characteristics of cells changed and began replicative senescence. THETC still could secret type I collagen normally. The chromosome of THETC was heteroploid (2n = 94). There were no hTERT mRNA expression. CONCLUSION: SV40 transfection can not make human embryonic tendon cells immortalization, on the other hand, human embryonic tendon cells transformed by ptsA58H plasmid has no tendency of malignant transformation.
OBJECTIVE: To explore the SV40-mediated immortalization, the related factors and their roles in cell immortalization. METHODS: The original articles about cell immortalization and replicative senescence in recent decade were reviewed. RESULTS: Cell immortalization was a multifaceted phenomenon, it was involved in viral DNA integration, activation of telomerase, inactivation of growth suppressors, and so on, and their roles were closely related. CONCLUSION: The research on cell immortalization may be expected to provide important insights into a broad range of cellular biological phenomenon, and the immortalized cells can play important roles in the research of cell engineering and tissue engineering as standard cells.