Id1 expression in the mouse mammary gland.

Santa Cruz SC-488 polyclonal antibody does not specifically recognise Id1. Mammary glands from 10 week old virgin wildtype (A) and Id1-null (B) mice were immuno-stained for Id1 using SC-488. Note the non-specific positive staining of epithelial cells regardless of genotype (inset). A spontaneous p53-null mammary tumor was immunostained for Id1 using SC-488 (C) or BCH-1/#37-2 monoclonal antibody (D). (E) BCH-1/#37-2 monoclonal antibody was used to immunostain for Id1 in Id1-transgenic mammary glands, or spleen taken from a wildtype (WT) or Id1-null mouse. Id1-positive cells in the spleen are endothelium. (F) Id1 immunostaining (BCH-1/#37-2) was conducted on mouse mammary glands at various stages of mammary gland development: 5 weeks old, 12 week old virgin, 4 days post-coitus (dpc), 18 dpc, lactating 4 days postpartum (dpp) and lactating 15 dpp. Arrows indicate examples of Id1-positive cells.