FIG. 3.

Human MUC1 expression at Days 1 and 4.5 of pregnancy in human MUC1 transgenics. Images show double labeling using CT-1, an antibody that recognizes both mouse and human MUC1, and 214D4, a monoclonal antibody that specifically recognizes human MUC1 at Days 1 and 4.5 in wild-type FvB and human MUC1 transgenics. Sections were analyzed by indirect immunofluorescence with anti-CT-1 (red), anti-214D4 (green), and draq5 (arbitrarily assigned the color blue) as described in Materials and Methods. Sections from Days 1 (A–D) and 4.5 postcoitum (E–H) from uteri of wild-type mice were used as controls to compare to human MUC1 transgenic uterine sections from Days 1 (I–L) and 4.5 postcoitum (M–P). Human MUC1 expression in glandular epithelia (indicated by arrows) on Day 4.5 postcoitum is also detected (Q–T). Bar = 100 μm.