Immortalized Human Esophageal Epithelial Cells-SV40 (Het-1A)

Immortalized human esophageal epithelial cells-SV40 (Het-1A) are established by transfecting normal human esophageal autopsy tissue with plasmid pRSV-T, which contains the Rous sarcoma virus long terminal repeat (RSV-LTR) promoter driving the simian virus 40 (SV40) large T-antigen gene. The advantages of Het-1A cells are fourfold. First, extended proliferative capacity – following a crisis period of 6–8 months, Het-1A emerged as a continuously growing line that has undergone more than 250 population doublings, with a doubling time of approximately 27.4 hours. This addresses the fundamental supply constraints of primary cultures. Second, retention of epithelial characteristics – Het-1A cells maintain epithelial morphology, stain positively for cytokeratins, and express the SV40 T-antigen. They remain responsive to physiological regulators: proliferation is stimulated by Ca²⁺ and inhibited by fetal bovine serum, transforming growth factor-beta 1 and 2. Third, non-tumorigenicity – Het-1A cells have remained non-tumorigenic in athymic nude mice for more than 12 months, confirming they are immortalized but not transformed, making them an appropriate normal control for carcinogenesis studies. Fourth, experimental reproducibility and scalability – the immortalized nature eliminates donor-to-donor variability inherent to primary cultures, enabling consistent, repeatable experiments and high-throughput screening. Het-1A cells are extensively used to model esophageal diseases including Barrett's esophagus, gastroesophageal reflux disease (GERD), and esophageal cancer, as well as to investigate responses to acid and bile reflux, oxidative stress, and chemopreventive agents.