Disorganization of basement membrane zone architecture causes impaired melanocyte inhabitation in vitiligo

Yang, F.; Yang, L.; Kuroda, Y.; Lai, S.; Takahashi, Y.; Sayo, T.; Namiki, T.; Nakajima, K.; Sano, S.; Inuoe, S.; Tsuruta, D.; Katayama, I.

doi:10.1101/2022.12.18.520911

bioRxiv · 10.1101/2022.12.18.520911

Disorganization of basement membrane zone architecture causes impaired melanocyte inhabitation in vitiligo

Yang, F.·Yang, L.·Kuroda, Y.·Lai, S.·Takahashi, Y.·Sayo, T.·Namiki, T.·Nakajima, K.·Sano, S.·Inuoe, S.·Tsuruta, D.·Katayama, I.

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Abstract

Vitiligo, a chronic autoimmune skin disorder characterized by selective epidermal melanocyte loss, lacks a well-defined mechanism for this phenomenon. Our study offers compelling insights into vitiligo pathogenesis by revealing disruptions in the basement membrane zone (BMZ) architecture. We observed branched, fragmented, and multilayered lamina densa, accompanied by elevated dermal fibroblast numbers and notable matrix metalloproteinase 2 (MMP2) overexpression. Vitiliginous skin extracts exhibited significant active MMP2 upregulation. To establish a direct link, we intradermally injected MMP2-overexpressing fibroblasts into K14-SCF transgenic mice, resulting in vitiligo-like skin and melanocyte loss, effectively reversed by coadministering MMP2 inhibitors. These groundbreaking findings highlight the pivotal role of disorganized BMZ in vitiligo, proposing MMP2 overexpression in dermal fibroblasts as a potential key contributor. Enhancing our understanding of vitiligos mechanisms, this research opens avenues for innovative therapeutic strategies against this challenging autoimmune skin disorder. TeaserDisrupted skin architecture and MMP2 in dermal fibroblasts hold the key to a potential breakthrough against this puzzling autoimmune disease vitiligo.

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Yang, F., Yang, L., Kuroda, Y., Lai, S., Takahashi, Y., Sayo, T., Namiki, T., Nakajima, K., Sano, S., Inuoe, S., Tsuruta, D., Katayama, I.. 2022-12-19. Disorganization of basement membrane zone architecture causes impaired melanocyte inhabitation in vitiligo. https://doi.org/10.1101/2022.12.18.520911

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