Cultures of exfoliated mammary epithelial cells: variation between donors.

Human milk contains clonogenic epithelial cells which give rise to three distinct colony types, namely, joined elongated, joined cuboidal, and open (i.e. unjoined). Previous studies have shown that these may be interrelated and may reflect stages in cell differentiation in the human mammary gland. This paper reports an analysis of paired milk samples from a series of donors, and shows that the predominant clonogenic cell type varies from donor to donor. This could reflect individual variation in the cell population of the lactating human breast.