EGFR inhibition results in less acute UV-induced skin injury. Mice were treated topically with AG1478 or vehicle alone and exposed to 10 kJ/m² UV or sham-irradiated. (a) Mice treated with AG1478 (right) or vehicle (left) were photographed at 24 h following UV exposure. (b) Skinfold thickness was measured daily following UV. Mean ± standard error is shown. mice. *Indicates a significant difference compared to the vehicle-treated and sham-irradiated group between 1 and 11 d after irradiation, **significant compared to the vehicle-treated and UV-exposed group between 3 and 9 d after UV, or ***significant compared to the sham-irradiated groups at 2 d and between 4 and 8 d after UV, using two-way ANOVA, where . (c) Hematoxylin- and eosin-stained sections revealed increased dermal cellularity in UV-exposed and vehicle treated skin 48 h after UV (200x magnification shown). (d) Neutrophils were counted in at least three 4x microscopic fields in hematoxylin- and eosin-stained sections with the investigator blinded as to the identity of the samples. The mean number of neutrophils per field ± standard error is shown. mice. (e) Mast cells were counted in 20x microscopic fields in tryptase-stained sections with the investigator blinded as to the identity of the samples. The mean number of tryptase-positive cells per field ± standard error is shown on left and representative images from UV-irradiated skin at the 24 h time point. mice. **Indicates a significant difference compared to the vehicle-treated control.