Fig. 1. C/EBP
is expressed in luminal epithelial cells. Immunohistochemistry
of C/EBP
in wild-type and C/EBP
null mammary glands at the
indicated time points of involution after 7 days of lactation. Representative
sections at 400 x and 50 x original magnification are shown
(insets). M, myoepithelial cells; solid arrows, positive stromal cells; open
arrows, negative stromal cells.