092 Reciprocal control of epidermis and sensory neurons in juvenile and adult human skin in a re-innervated epidermis model

Skin is in constant evolution from the embryo state, reciprocal control between epidermis and neurons different ages of life little known. Our objective was to characterize epidermal neuronal interaction juvenile or adult using a new model re-innervated epidermis. Human sensory were obtained iPS cells, their differentiation functionality validated by observation morphology, markers expression, increase intracellular calcium following lactic acid (LA) stimulation. cultured presence donors. After 3 6 days co-culture, reinnervation confirmed PGP9.5 immunostaining revealing nerve fibers The reinnervated able response stimulation, induced LA, increasing substance P production. Further investigations performed innervated Those possess homeostasis traits with without innervation, as shown TUNEL, KI67 p63 staining: non-innervated condition longer culture time non-significant apoptotic showed decrease proliferative cells compared adults, innervation non-significantly increased stem number. Gene expression barrier function qPCR highlighted distinct transcriptomic profile most more expressed We developed demonstrated that age induce characteristics. In addition our previous work showing keratinocytes trophic properties on neurons, we suggest interactions skin could homeostasis.