EXPERIMENTAL FIGURE 20-6 Antibodies to fibronectin block branching morphogenesis in developing mouse tissues. Immature salivary glands were isolated from murine embryos and allowed to undergo branching morphogenesis in vitro for 10 hours in the absence (a) or presence (b) of an antibody that binds to and blocks the activity of the ECM molecule fibronectin. Anti-fibronectin antibody (Anti-FN) treatment blocked branch formation (arrowheads). Inhibition of fibronectin’s adhesion receptor (an integrin) also blocks branch formation (not shown). Scale bar, 100 µm.

[Republished with permission of Nature, from Sakai, T., et al., “Fibronectin requirement in branching morphogenesis,” Nature, 2003, 423(6942):876–81; permission conveyed through the Copyright Clearance Center, Inc.]