A clonal stem cell line established from a mouse mammary placode with ability to generate functional mammary glands.

The mammary gland develops from the placode at ectodermal invagination. The rudimentary parenchyma (mammary bud) develops mammary trees and alveolar structures, suggesting that the mammary bud consists of stem/progenitor cells. Here, we established a clonal stem cell line from a mammary bud of a p53 null female embryo at day 14.