Figure 8

A major subset of ductal luminal cells show Ltbp1L activity. (A) Carmine/5-bromo-4-chloro-3-indolyl-β-D-galactoside (X-Gal)-stained whole mount of the terminal end bud, (B) nuclear fast red-stained section of the mature duct show Ltbp1L-LacZ expression in luminal cells, basal cells are visualized by immunohistochemcal detection of p63 (inset). Flow cytometry gating for FDG-Gal⁺ (Ltbp1L-LacZ)⁺ cells enriches for the luminal CD24⁺CD49^LO compartment (C, top panel). Ltbp1L-LacZ marks 65% of total luminal cells (C, middle panel), and 35% of luminal cells are Ltbp1L-LacZ-negative (C, bottom panel). Gates represent stromal S, luminal L, and basal B populations from two mature virgin mice. (D-F) Histograms show Ltbp1L-LacZ -positive cells (red) are CD29^LO(D), Sca-1^HI(E) and CD61^LO(F). Data represents n = 2 replicates for all experiments. Peaks represent luminal L, basal B, mature luminal ML and luminal progenitors LP. Scale bars represent distance in microns.