Transgenic overexpression of VEGF-A induces a psoriasis-like phenotype after experimental induction of inflammation. One month after challenge, the ears of wild-type mice showed normal histoarchitecture and no apparent sign of inflammation (A). In VEGF-A–overexpressing mice, the challenged skin showed epidermal hyperplasia, fingerlike communicating epidermal protrusions into the dermis and a dense inflammatory infiltrate (B). A few CD4⁺ and CD8⁺ T cells (arrowheads) were scattered throughout the dermis of wild-type mice (C and E) one month after challenge whereas in VEGF-A transgenic mice, dense CD4⁺ infiltrates were found in the dermis (D) and CD8⁺ cells predominantly in the epidermis (F). Stains: (A-B) hematoxylin and eosin, (C-D) CD4, (E-F) CD8. Scale bar: 100 μm. At 24 hours after challenge, lymph nodes draining the oxazolone-challenged ears of VEGF-A transgenic mice contained 3.5 times more lymphocytes (G), as compared with wild-type mice. After 7 days, the number of lymphocytes remained highly elevated in the lymph nodes draining oxazolone-challenged sites in VEGF-A transgenic mice (H). No major differences in the number of activated T-lymphocytes were found in inguinal lymph nodes. Data are expressed as mean plus or minus SEM (n = 3 per condition and time point). *P < .05; **P < .01.