MCs and vascular endothelium are intimately associated. (A) MCs (blue, stained with the heparin-binding probe, avidin) are visible lining blood vessels (CD31, red) in tissue from the mouse ear, which was stained in whole mount (20× mag. 20×/0.75). (B) Proximity of MCs (blue) to blood (red, CD31) and lymphatic (green, LYVE-1) vessels in the mouse skin (20× mag. 20×/0.75 objective). (C) Extensive association of MCs with both vasculatures is apparent after staining mouse ear tissue in whole mount as in other panels for vascular and lymphatic endothelia (10× magnification, 10×/0.25 NA objective). Images were acquired using a Nikon Eclipse TE200 microscope and EZ-C1 Version 3.6 software. Additional image processing was performed using Autoquant software and Adobe Photoshop (Version 9).