Primary cells normally can only undergo a limited number of cell divisions in culture, and then enter replicative senescence where they can no longer divide. Scientists need to frequently re-establish fresh culture from tissues, which can be tedious and can add to variability from one preparation to another. Immortalized cells derived from primary cells can surpass normal cellular senescence and have extended replicative capacity. Immortalized cells are highly useful for research in cell biology as they are easier to culture and maintain; thus enabling scientists to use the same consistent cells through research projects for longitudinal studies.

Several methods exist for immortalizing mammalian cells in culture conditions. Simian virus 40 (SV40) T antigen can induce Telomerase activity in the infected cells and has been shown to be the simplest and most reliable agent for the immortalization of many different cell types. . The most recently discovered approach to cell immortalization is through the expression of Telomerase Reverse Transcriptase protein (TERT). This approach is particularly useful for cells that are most affected by telomere length, including many human cell types. TERT is usually silenced in most somatic cells. These cells are able to avoid replicative senescence by maintaining sufficient telomere lengths when hTERT is exogenously introduced. However, over-expression of hTERT in some cell types (especially in epithelial cells) fails to induce cell immortalization.

With years of experiences, our scientists can successfully produce stably immortalized custom cell lines by introducing either SV40 T antigen or TERT (successful species: Human, Bovine, Pig, Dog, Rat and Mouse) to meet your requirements. Our workflow is illustrated below:

Human dermal fibroblasts were immortalized by introducing SV40 T antigen. The immortalized human fibroblasts surpassed replicative senescence and be able to passage more than 30 passages without showing any proliferation deficits.