Purchase this article with an account.
Terry G Coursey, Johanna Tukler Henriksson, Meng Chen, Stephen C Pflugfelder; IFN-γ influences the proliferation and differentiation of conjunctival goblet cells. Invest. Ophthalmol. Vis. Sci. 2014;55(13):2774.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To test the hypothesis that IFN-γ inhibits conjunctival goblet cell growth and differentiation.
Primary conjunctival epithelial cultures were established from fresh tissue explants of murine palpebral conjunctiva. Cultures were incubated with Keratinocyte SFM (KSFM) medium supplemented with 40 ng/mL murine EGF and 3% fetal bovine serum. Cultures were treated with 0.1 ng/mL of IFN-γ for seven or 14 days. IFN-γKO were also examined. Cell proliferation was measured by WST-1 assay. Keratin 7 (K7), MUC5AC, Annexin V were immunodetected by immunofluorescent staining. K7, MUC5AC, MHC class II mRNA expression were measured by quantitative real time PCR.
Positive K7 and MUC5AC immunofluorescent staining confirmed the growth of conjunctival epithelium and goblet cells in untreated control cultures. WST-1 cell viability assay showed cultures initiated from IFN-γKO mice had 2.24 fold and 2.01 fold greater number of viable cells at 7 and 14 days, respectively, compared to those from WT C57BL/6 mice. Conjunctival cultures treated with minuscule concentrations of IFN-γ (0.1 ng/ mL) do not express K7 or MUC5AC, manifest a spindle-like appearance, and are strongly Annexin V positive. PCR analysis indicated that IFN-γ-treated cultures had a two-fold decrease in MUC5AC expression and a 10-fold decrease in K7 expression compared to untreated cultures. In contrast, IFN-γ-treated cultures had 283-fold increase in expression of MHC class II compared to untreated cultures. A significant 2.58 fold elevation in MUC5AC mRNA transcripts was observed IFN-γKO cultures compared to WT C57BL/6 cultures, but K7 mRNA transcripts were not significantly different between the two strains.
Our findings show that murine conjunctival cultures treated with very low concentrations of IFN-γ do not become goblet cells like untreated cultures. Conjunctival explants from IFN-γ deficient mice have increased growth and differentiation compared to wild-type mice and increased expression of MUC5AC. This study suggests that IFN-γ suppresses conjunctival epithelial growth and goblet cell differentiation.
This PDF is available to Subscribers Only