Macroscopic phenotype of Ang-2 transgenic mice. Ang-2 DT mice with high Ang-2 protein level in the serum display signs of skin erythema starting after 6 months of transgene expression (arrowheads). (A) Arrowheads in lower right panel point at dilated tail vein of an Ang-2 DT mouse. (B) Human Ang-2 serum levels secreted in the peripheral blood of Ang-2 DT mice after doxycycline depletion were determined by ELISA.