“Inflammatory priming” by epithelial mediated stromal inflammatory cell recruitment in K14-HIF-1αDPM transgenic mice. Redness and prominent vasculature of ear skin in transgenic mice (DPM) (B), which are not evident in nontransgenic mice (NTG) (A). Human HIF-1α mRNA (C) and total (human and potentially mouse) HIF-1α protein (D) are detectable only in transgenic ears. Ear histology reveals increased dermal cellularity in transgenic mice (F, arrows), compared with nontransgenic mice (E). Differential increase in subepidermal microvessels, revealed by MECA-32 immunohistochemistry (green), and lymphatic dilatation, LYVE-1 antibody (red, see white arrow) in DPM transgenic mice (H) versus nontransgenic controls (G). Endothelial activation evidenced by ICAM-1 immunohistochemistry, in transgenic (J), versus nontransgenic (I) ears. Increased number of CD45.1 positive inflammatory cells in transgenic (L) versus nontransgenic (K) ears. A 2- to 3-fold increase of neutrophils, mast cells, macrophages, and lymphocytes, determined by differential immunohistochemical analysis of inflammatory markers as indicated in panel M. Bar in panel F represents 100 μm.