Abstract
Purpose :
Pinkie mice with a loss of function mutation in retinoid X receptor alpha (RXRα) have been reported to develop dry eye with aging (Du et al. 2005). The purpose of this study is to compare immune cell populations and conjunctival goblet cell density in the conjunctiva of wild type (WT) and Pinkie strains and evaluate RXRα expression in these cell types in the normal conjunctiva.
Methods :
Confocal microscopy of conjunctival whole mount mounts and sections from young and older Pinkie and WT (6-8 weeks and 20-weeks) evaluated location and density of MHCII+CD11b+, MHCII+CD11c+ antigen presenting cells and WGA+ (or MUC5AC+) goblet cells.
Results :
Compared to WT, young and older Pinkie mice had increased MHCII+CD11b+ and CD11c+ cells in the stroma and epithelium and decreased goblet cell density. Goblet cells and CD11b+ cells stained positively for RXRα in WT. PCR for RXRα showed higher expression in cultured conjunctival goblet cell than corneal epithelium.
Conclusions :
Loss of RXRα signaling results in increased density of CD11b+ cells and reduce number of conjunctival goblet cells. RXRα is expressed in both of cell types. These findings suggest that RXRα mediated pathways regulate goblet cell mucin production and the immune environment in the conjunctiva.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.