Department of Dermatology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan.
Published: June 2022
AI Article Synopsis
Article Abstract
Vertebrates exhibit patterned epidermis, exemplified by scales/interscales in mice tails and grooves/ridges on the human skin surface (microtopography). Although the role of spatiotemporal regulation of stem cells (SCs) has been implicated in this process, the mechanism underlying the development of such epidermal patterns is poorly understood. Here, we show that collagen XVII (COL17), a niche for epidermal SCs, helps stabilize epidermal patterns. Gene knockout and rescue experiments revealed that COL17 maintains the width of the murine tail scale epidermis independently of epidermal cell polarity. Skin regeneration after wounding was associated with slender scale epidermis, which was alleviated by overexpression of human COL17. COL17-negative skin in human junctional epidermolysis bullosa showed a distinct epidermal pattern from COL17-positive skin that resulted from revertant mosaicism. These results demonstrate that COL17 contributes to defining mouse tail scale shapes and human skin microtopography. Our study sheds light on the role of the SC niche in tissue pattern formation.
Background: Bullous pemphigoid (BP) and mucous membrane pemphigoid (MMP) are rare autoimmune blistering disorders characterized by autoantibodies (autoAbs) targeting dermo-epidermal junction components such as BP180 and BP230. The differential diagnosis, based on both the time of appearance and the extension of cutaneous and/or mucosal lesions, is crucial to distinguish these diseases for improving therapy outcomes and delineating the correct prognosis; however, in some cases, it can be challenging. In addition, negative results obtained by commercially available enzyme-linked immunosorbent assays (ELISAs) with BP and MMP sera, especially from patients with ocular involvement, often delay diagnosis and treatment, leading to a greater risk of poor outcomes.
This case report details the presentation, diagnosis, and management of a newborn Native American male with non-Herlitz junctional epidermolysis bullosa (JEB), a rare diagnosis specifically in the Native American population. Genetic analysis revealed a homozygous mutation in the COL17A1 gene. The management involved multidisciplinary care and highlighted the challenges in treatment, including pain management, wound care, and ethical considerations surrounding adoption within Indigenous communities.
Nerves play a crucial role in maintaining the balance and development of epithelial stem cells, particularly during tooth development in rats.
A study showed that when sensory nerves were damaged, it led to issues like impaired mineralization and thinner enamel in the rats' incisors.
Key enamel-related factors, such as ameloblastin and amelogenin, were found to be less expressed after nerve injury, suggesting that sensory nerves are important for proper enamel formation and mineralization.
Integrin α6β4 subunits and type XVII collagen are critical transmembrane proteins involved in cell-matrix adhesion in skin, while laminin 332 serves as their ligand in the basement membrane zone (BMZ). Those proteins contribute to the composition of hemidesmosomes (HDs) and pathogenic variants in their corresponding genes cause junctional epidermolysis bullosa (JEB). Although the genotype-phenotype relationships in JEB have been extensively studied, the pathogenetic changes of extracellular matrix (ECM) and cell-matrix adhesion resulting from gene mutations remain unclear.
Background: Bullous pemphigoid (BP) is a rare autoimmune blistering disease predominantly affecting the elderly population.
Objectives: The present study aims to identify clinical factors that may influence outcomes of BP, including skin phenotype, serology, mucosal involvement, pruritus, and triggers.
Methods: A retrospective analysis was conducted on 70 cases with BP registered from January 2019 to December 2022.
