1188 Disorganization of basement membrane zone architecture for impaired melanocyte inhabitation in vitiligo

Vitiligo is an acquired hypomelanotic disorder characterized by the absence of melanocytes. The mechanism melanocyte loss remains unclear. In this study, we aimed to explore underlying mechanism. By electron microscopy and immunohistochemistry, branching fragmented basement membranes (BM) were identified in vitiligo skin. To determine why BM was altered vitiligo, expression matrix metalloproteinase 2 (MMP2) MMP9 skin sections analyzed. upper dermis fibroblasts secreted MMP2 dramatically increased. After transplanting that overexpress MMP2, disruption disappearance observed 3D equivalents cultured ex vivo explants. situ proximity ligation assay, a dramatic decrease integrin-laminin binding observed, albeit no change individual levels. Furthermore, immunoelectron revealed aberrant distribution laminin decreases binding. Finally, Krt14-Kitl mice, depigmentation patches on mice’s backs MMP2-overexpressing fibroblasts, inhibition reversed depigmentation. These findings imply elevated production dermal may play crucial role melanocytes through melanocyte-BM junction inhibitors be effective treatment.