Culture of hormone-dependent functional epithelial cells from rat thyroids.

TLDR

Primary rat thyroid cells were cultured in medium containing 0.1–0.5 % calf serum plus insulin, thyrotropin, transferrin, hydrocortisone, somatostatin, and glycyl‑L‑histidyl‑L‑lysine acetate. The FRTL strain, obtained by successive colonial isolations, maintained highly differentiated features—including physiological thyroglobulin secretion and 100‑fold iodide concentration—for more than three years in continuous culture, whereas conventional culture conditions caused loss of these traits, indicating that low serum and hormone supplementation preserve epithelial differentiation and may be applicable to other epithelial cells.

Abstract

Primary cultures of rat thyroid cells were made in medium supplemented with 0.1--0.5% calf serum and containing six hormones or growth factors: insulin, thyrotropin, transferrin, hydrocortisone, somatostatin, and glycyl-L-histidyl-L-lysine acetate. The FRTL strain was purified by successive colonial isolations and was found to maintain highly differentiated features (secretion into the culture medium of physiological amounts of thyroglobulin and concentration of iodide by 100-fold). The FRTL strain has been observed for more than 3 years in continuous culture. It has maintained the same biochemical and morphological characteristics that typified the primary cultures of thyroid follicular cells immediately after their enzymatic release from the rat thyroid. Thyroid epithelial cells that were grown under more conventional cell culture conditions failed to retain these specialized characteristics. We show that maintenance in vitro of these specialized functions of rat thyroid follicular cells is dependent on low serum concentrations and supplementation with hormones in the primary cultures. Our observations indicate that this culture strategem may be aplicable to the general problem of maintenance of differentiated characteristics in cultures of other epithelial cells.