405 Atopic dermatitis patients have decreased epidermal innervation but increased neuronal substance p expression

Severe pruritus in atopic dermatitis (AD) significantly impairs patients’ quality of life, primarily due to relentless itching. Sensory nerves the epidermis are important mediating sensation itch, but there is conflicting evidence whether epidermal nerve density increased or decreased lesional skin AD. Here we measured length, branching, and neurotransmitter expression healthy controls non-lesional AD patients. Four millimeter punch biopsies were taken from 8 adult control patients with moderate-to-severe Biopsies fixed immunostained. Epidermal sensory identified by staining pan-neuronal marker, PGP9.5, neuroinflammatory substance P. length branching optically cleared, whole-mount tissue using confocal microscopy Imaris 3D digital modeling software. Average was 667 (±352) nm 445 (±270) 273 (±177) (p = 0.04). number branch points also 7 (±6) patient 3 (±3) 2 (±1) skin. Colocalized neuronal P volume 13 (±17) μm3 21 (±27) 27 (±18) The ratio PGP 0.03 (±0.03) 0.26 (±0.4) 0.28 (±0.3) 0.02). In conclusion, have innervation Despite this decrease overall density, may contribute