Mmp2 deficiency affects early tail dermal lymphangiogenesis. (A) Dermal lymphatic vasculature is visualized in Mmp2-deficient mice (Mmp2 KO) and WT mice by whole-mount LYVE-1 immunohistochemistry on postnatal days 5 and 11. LRC forming in the honeycomb network is delineated on original pictures (white arrow; A) and outlined in red through a computerized method (B). Images in panels A and B are representative of at least 40 images (n = 5). (C) Mean ring-area was determined with a computerized method as described in “Tail and ear whole-mount preparations.” The densities of vessel skeleton (delineated in red) and intersections (yellow points; D) were determined by a computer-assisted method (E). Results are expressed as percentage of control. Error bars indicate SEM. Bars represent 200 μm in each panel. Tissues stained with Alexa Fluor 488 (Molecular Probes) were used mounted in Vectashield mounting medium (Vector Laboratories) and excited using a multi-Argon laser. Panels are Z-stack average projections of Z-series pictures that were acquired at room temperature, on a TCS SP2 confocal microscope (Leica Microsystems) with a 2 μm step size using Leica Confocal 2.5 acquisition software (Leica) and a 10× NA 0.3 HC PL FLUOTAR lens (Leica).