Noninvasive evaluation of vascular endothelial growth factor-A (VEGF-A) protein concentrations in the stratum corneum and serum of healthy and atopic dogs.

BACKGROUND: Vascular endothelial growth factor (VEGF) is a cytokine involved primarily in angiogenesis. In human atopic dermatitis (AD), VEGF has been detected in the stratum corneum and blood. OBJECTIVE: To evaluate VEGF-A expression in the serum and stratum corneum of healthy and atopic dogs, and its possible correlation with disease severity in atopic dogs. ANIMAL: Fifteen atopic and 15 healthy, privately owned dogs. METHODS AND MATERIALS: The severity of clinical signs associated with AD was evaluated with the Canine Atopic Dermatitis Extent and Severity Index (CADESI-04). For all dogs, a single blood sample was performed and serum collected. Tape stripping (15 times) was performed on the left periocular area (lesional skin). A commercially available canine-specific VEGF-A enzyme-linked immunosorbent assay was performed with all samples. RESULTS: Vascular endothelial growth factor-A was undetectable in the serum. In the stratum corneum, there was no significant difference in VEGF-A concentrations between healthy (mean 89.4 ± 59.5 pg/ml) and atopic dogs (mean 100.3 ± 77.1pg/ml) (P = 0.71). There was no correlation between stratum corneum VEGF-A concentrations and CADESI-04 scores. CONCLUSIONS AND CLINICAL IMPORTANCE: The role of VEGF in canine AD is unclear. Because of many variants, VEGF-C and VEGF-D or VEGF-A isotopes should be explored in the skin to better evaluate the role of VEGF in canine atopy. Full-thickness skin biopsy, molecular biology and histopathological investigation may be necessary to further assess cutaneous VEGF expression.