title: Growth and differentation of rat mammary epithelial cells cultured in serum-free medium.
abstract: A new serum-free defined medium was developed that supports the growth of normal rat mammary epithelial cells. Mammary organoids from the glands of female F344 rats were cultured in a serum-free medium. Monolayer culture colonies developed within a week and remained viable for months in culture. Upon subculture of one-week-old primary colonies, almost the same morphology of colonies was developed. The scrape loading/dye transfer technique showed that most of colonies that developed in a serum-free medium containing EGF, human transferrin, insulin, and hydrocortisone (basal serum-free medium, BSFM) failed to show cell-cell communication. However, colonies cultured in BSFM supplemented with prolactin, E(2), and progesterone (complete hormone serum-free medium, CHSFM) showed cell-cell communication at 14 days of primary culture or of subculture. By flow cytometry with FITC-PNA and PE-anti-Thy-1.1 monoclonal antibody, we distinguished four RMEC subpopulations in cultures in both media: Thy-1.1+ cells, PNA+ cells, cells negative to both reagents and cells positive to both reagents. It is likely that combined prolactin, cortisol, and insulin in CHSFM stimulate terminal differentiation of clonogenic cells.
authors.affiliation: College of Pharmacy, Pusan National University, 609-735, Pusan, Korea.
authors.forename: D Y
authors.initials: DY
authors.lastname: Kim
authors.forename: B H
authors.initials: BH
authors.lastname: Jhun
authors.forename: K H
authors.initials: KH
authors.lastname: Lee
authors.forename: S C
authors.initials: SC
authors.lastname: Hong
authors.forename: K H
authors.initials: KH
authors.lastname: Clifton
authors.forename: N D
authors.initials: ND
authors.lastname: Kim