Binding and uptake of immunoglobulins by mouse mammary gland epithelial cells in hormone-treated cultures

Abstract

To study binding and uptake of immunoglobulins by mammary gland epithelial cells in culture, mouse mammary glands were taken from lactating animals. The exocrine epithelial cells were dispersed and cultured as monolayers in the presence of insulin. Insulin, progesterone, estrogen and prolactin in combination were then used during the final period of subculture. Such four-hormone treatment induced the production of differentiated products such as casein and the structural changes seen in fully developed lactating mammary gland epithelial cells. Induced cells exposed to mouse IgM, IgG, monomeric or dimeric serum-type IgA, or secretory IgA exhibited significant binding and internalization mainly of dimeric serum IgA as assessed by immunofluorescence and enzyme immunoassay.