Purchase this article with an account.
Balaraj Balaram Menon, Xiaohong Zhou, Sandra Spurr-Michaud, James Chodosh, Ilene K Gipson; Epidemic Keratoconjunctivitis-causing Adenoviruses Induce MUC16 Ectodomain Release in Corneal Epithelial Cells. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):1869. doi: https://doi.org/.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Membrane-associated mucins (MAMs) that are expressed on the apical side of all mucosal epithelia of the body interfere with pathogen adhesion and invasion. Nevertheless, certain pathogens overcome the MAM barrier prior to initiating infection and associated inflammation. The purpose of this study is to test the hypotheses that 1) ectodomain release of MAMs, primarily MUC1 and MUC16, is a pre-requisite step for establishment of adenoviral infections at the ocular surface and 2) MUC1 and MUC16 regulate the inflammatory response associated with adenoviral keratoconjunctivitis.
Telomerase-immortalized human corneal-limbal epithelial (HCLE) cells, grown to confluence and allowed to differentiate for optimal mucin expression, were exposed to HAdV-D37 (EKC-causing) and HAdV-D19p (non EKC-causing, control), each at an MOI of 3, for 2 h. Following exposure, equal volumes of cell culture supernatants were harvested, concentrated, and analyzed for released ectodomains of MUC1 and MUC16 by immunoblotting. To determine if MUC1 and MUC16 regulate the inflammatory response associated with HAdV-D37 infection, HCLE cells and those knocked down for MUC1 (HCLE-shMUC1) or MUC16 (HCLE-shMUC16), and corresponding scramble-transfected cells (HCLE-scrMUC1 and HCLE-scrMUC16) were exposed to empty HAdV-D37 capsids for 1 h, following which mRNA was extracted from the different cells, and IL-8 message levels quantified by qRT-PCR as an outcome of inflammatory response.
1) The EKC-causing HAdV-D37, but not the non EKC-causing HAdV-D37, induced MUC16 ectodomain release. No ectodomain release of MUC1 was observed. 2) HCLE-shMUC1 and HCLE-shMUC16 cells exhibited a 2-2.5 fold increase in IL-8 message levels upon exposure to empty HAdV-D37 capsids in comparison to HCLE-NT, HCLE-scrMUC1, and HCLE-scrMUC16 cells.
Results suggest that adenovirus-induced ectodomain release of MUC16 may be a pre-requisite step for establishment of adenoviral infections at the ocular surface and that MUC1 and MUC16 may be involved in suppressing the inflammatory response associated with such infections.
This PDF is available to Subscribers Only