Altered ciliary morphofunction in the oviductal infundibulum of systemic autoimmune disease-prone MRL/MpJ-Faslpr/lpr mice

According to our previous reports, impaired oocyte pickup was observed in the oviductal infundibulum of an autoimmune disease (AD) mouse model, suggesting a relationship between female infertility and AD. This study examines the relationship between AD and infundibulum morphofunction by focusing on the epithelial cilia. Healthy MRL/MpJ and AD-prone MRL/MpJ-Fas(lpr/lpr) mice were examined at 3 and 6 months of age, representing early and late disease stages, respectively. Oocyte pickup indices decreased with AD progression indicated by splenomegaly, autoantibody production and increased T cell counts of infundibulum mucosa in MRL/MpJ-Fas(lpr/lpr) mice. Ciliary beating frequency (CBF) and height in the infundibulum were faster and higher in MRL/MpJ-Fas(lpr/lpr) mice than in MRL/MpJ mice at the early AD stages, although the absolute CBF values were lower at the late AD stage. At the late stage, ciliary height did not differ between mouse lines but the morphological index of cilia beating direction indicated randomized patterns in MRL/MpJ-Fas(lpr/lpr) mice. The tracheal mucosa was also examined as a representative example of cilia morphology; its CBF decreased at the late AD stage in MRL/MpJ-Fas(lpr/lpr); however, there were no AD-related morphological changes. Our results demonstrate altered cilia motility in systemic and reproductive organs, with such morphological changes of the infundibulum likely impairing function, including oocyte pickup.