Figure 2.

Confocal microscopic images of vascular basement membrane stained by type IV collagen (A), laminin (B), and fibronectin (C) immunoreactivities in sequential sections of MCa-IV tumor. All three basement membrane proteins co-localize with CD31 immunoreactivity in the same sections (D–F). Type IV collagen immunoreactivity is primarily restricted to blood vessels in these tumors, but laminin and fibronectin immunoreactivities are also present elsewhere in the tumors. Laminin (G) and entactin/nidogen (H) immunoreactivities and corresponding CD31 immunoreactivity (I, J) are shown associated with blood vessels in RIP-Tag2 tumors. Arrows in H mark exocrine pancreatic acini outlined by entactin/nidogen immunoreactivity. Scale bars: 170 μm (A–F); 50 μm (G–J).