Glycosylation and annexin II cell surface translocation mediate airway epithelial wound repair

Abstract

Glycosylation of cell surface proteins can regulate multiple cellular functions. We hypothesized that glycosylation and expression of glycoproteins after epithelial injury is important in mediating repair. We report the use of an in vitro culture model of human airway epithelial cells (1HAEo(-)) to identify mediators of epithelial repair. We characterized carbohydrate moieties associated with repair by their interaction with the lectin from Cicer arietinum, chickpea agglutinin (CPA). Using CPA, we identified changes in cell surface glycosylation during wound repair. Following mechanical wounding of confluent monolayers of 1HAEo(-) cells, CPA staining increases on the cell surface of groups of cells in proximity to the wound edge. Blocking the CPA carbohydrate ligand inhibited wound repair highlighting the role of the CPA carbohydrate ligand in epithelial repair. Annexin II (AII), a calcium-dependent, membrane-associated protein, was identified as a protein associated with the CPA ligand. By membrane protein biotinylation and immunodetection, we have shown that following mechanical wounding, the presentation of AII on the cell surface increases coordinate with repair. Cell surface AII accumulates in proximity to the wound. Furthermore, translocation of AII to the cell surface is N-glycosylation dependent. We are the first to demonstrate that following injury, N-glycosylation events and AII presentation on the cell surface of airway epithelial cells are important mediators in repair.

Annexin A2 and S100A10 Regulate Human Papillomavirus Type 16 Entry and Intracellular Trafficking in Human Keratinocytes

“…Both AnxA2 and S100A10/p11 are expressed in the stratified epithelium (56)(57)(58), but AnxA2 expression in intact and wounded skin is more concentrated to the surface of basal cells (57,58). Currently, there is no direct evidence to suggest that a cellular receptor dictates cell-or tissue-specific tropism for papillomaviruses.…”

“…AnxA2 is predominantly expressed in the endocervix and basal layers of epithelia and the ectocervix (56,58), whereas S100A10 is expressed in both basal and suprabasal cells (57). Upon HK wounding in culture, AnxA2 expression increases at the cell surface (58), and knockdown of AnxA2 alters wound-induced HK migration (59).…”

The annexins: spatial and temporal coordination of signaling events during cellular stress

“…Annexin A2 was implicated in wound closure in several studies. Patchell et al [204] examined the role of glycosylation and expression of glycoproteins after epithelial injury and demonstrated that following injury, N-glycosylation events and annexin A2 presentation on the cell surface of airway epithelial cells are important mediators in repair [204]. Following mechanical wounding of confluent monolayers of human airway epithelial cells, glycosylation staining increased on the cell surface of groups of cells in the proximity of the wound edge.…”

Erythropoietin inhibits respiratory epithelial cell apoptosis in a model of acute lung injury

“…Paraffin-embedded sections of normal lung parenchyma from patients undergoing lung resection were obtained from the Tissue Registry (iCAPTURE Centre, Vancouver). Slides were processed with standard techniques of Citra buffer heat-induced antigen retrieval procedure (Dako, Mississauga), Following blocking, slides were incubated in primary antibody (rabbit anti-EPOR 1:50 or rabbit IgG isotype control 1:200) overnight at 4uC and immunostained as previously described [23].…”