Figure 3.

MG atrophy and signs of DED in Fgfr2^CKO mice. (A, B) ORO lipid staining in control and Fgfr2^CKO mice. Upper eyelids were dissected from control mice (fed regular chow) and Fgfr2^CKO mice (fed Dox chow for 10 days) and subjected for whole-mount ORO staining to view lipid (meibum) production by MG acini (arrows labeled a). Meibum secreted into main duct (arrowhead labeled d) was stained in a dark-red color in control mice (A). Compared with control mice, Fgfr2^CKO mice exhibited a reduction of MG acinar area and meibum production (B). (C, D) Compared with control mice (C), Fgfr2^CKO mice showed signs of ocular irritation, including loss of corneal luster and macerated eyelids, after extended (2 to 3 weeks) Dox chow feeding (D). Such signs of ocular irritation were likely due to increased tear evaporation and tear film instability.