Dataset Information

Differential Distribution of Laminin N-Terminus ?31 Across the Ocular Surface: Implications for Corneal Wound Repair.

ABSTRACT:

Purpose

Laminin N-terminus (LaNt) ?31 is a relatively unstudied protein derived from the laminin ?3 gene but structurally similar to netrins. LaNt ?31 has, to date, been investigated only in two-dimensional (2D) keratinocyte culture where it influences cell migration and adhesion, processes integral to wound repair. Here we investigated LaNt ?31 distribution in ocular surface epithelium, during limbal stem cell activation, and corneal wound healing.

Methods

Human, mouse, and pig eyes, ex vivo limbal explant cultures, and alkali burn wounds were processed for immunohistochemistry with antibodies against LaNt ?31 along with progenitor cell-associated proteins. LaNt ?31 expression was induced via adenoviral transduction into primary epithelial cells isolated from limbal explants, and cell spreading and migration were analyzed using live imaging.

Results

LaNt ?31 localized to the basal layer of the conjunctival, limbal, and corneal epithelial cells. However, staining was nonuniform with apparent subpopulation enrichment, and some suprabasal reactivity was also noted. This LaNt ?31 distribution largely matched that of keratin 15, epidermal growth factor receptor, and transformation-related protein 63? (p63?), and displayed similar increases in expression in activated limbal explants. During active alkali burn wound repair, LaNt ?31 displayed increased expression in limbal regions and loss of basal restriction within the cornea. Distribution returned to predominately basal cell restricted once the wounded epithelium matured. Cultured corneal epithelial cells expressing LaNt ?31 displayed increased 2D area and reduced migration, suggesting a functional link between this protein and key wound repair activities.

Conclusions

These data place LaNt ?31 in position to influence laminin-dependent processes including wound repair and stem cell activation.

SUBMITTER: Barrera V

PROVIDER: S-EPMC6735649 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Publications

Differential Distribution of Laminin N-Terminus α31 Across the Ocular Surface: Implications for Corneal Wound Repair.

Barrera Valentina V Troughton Lee D LD Iorio Valentina V Liu Siyin S Oyewole Olutobi O Sheridan Carl M CM Hamill Kevin J KJ

Investigative ophthalmology & visual science 20180801 10

<h4>Purpose</h4>Laminin N-terminus (LaNt) α31 is a relatively unstudied protein derived from the laminin α3 gene but structurally similar to netrins. LaNt α31 has, to date, been investigated only in two-dimensional (2D) keratinocyte culture where it influences cell migration and adhesion, processes integral to wound repair. Here we investigated LaNt α31 distribution in ocular surface epithelium, during limbal stem cell activation, and corneal wound healing.<h4>Methods</h4>Human, mouse, and pig e ...[more]

PMID: 30098195

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