621 Heterogeneity: a new insight in deciphering keloid physiopathology

Keloids are hypertrophic and proliferating pathological scars extending beyond the initial lesion without any tendency to regression. Usually, keloids consideredand treated as a single entity but clinical observations suggest heterogeneity in keloid morphologies with distinction of extensive nodular entities. Within keloid, could also be detected between superficial deep dermis or center periphery. Focusing on fibroblast main actor formation, we aimed at evaluating intra interkeloid fibroblasts order improve our understanding pathogenesis. Fibroblast cultures were obtained from mature (center vs periphery, dermis) compared control healthy skin. Functional (migration, proliferation traction forces) gene analyses each subpopulation performed TGF-β activation. Results showed that keloids, migration peripheral was significantly higher than central ones it keloids. No significant variations found for basal proliferation, whereas TGF-β-induced one controls. Extensive exhibited forces did papillary reticular ones. activation by into myofibroblasts expression aSMA extracellular matrix production skin, rather sublocalisation Altogether, results enable identifying least two entities through features within differ according their location periphery dermis. These heterogeneities may lead better pathophysiology adapt treatments.