Immunohistochemical observation of meibomian gland following ocular surface alkali burning in wild-type and Smad3-deficient mice

Program Number: 13 Poster Board Number: A0001 Presentation Time: 8:30 AM–10:15 AM Immunohistochemical observation of meibomian gland following ocular surface alkali burning in wild-type and Smad3-deficient mice Shin Mizoguchi1, Yuka Okada1, Reiko Arita2, Shizuya Saika1. 1Ophthalmology, Wakayama Medical University, Wakayama, Japan; 2Ophthalmology, Itoh Clinic, Saitama, Japan. Purpose: To immunohistochmeically examine the pathology of meibomian glands following ocular surface alkali burning and investigate the effects of lacking Smad3 in alkali burn-induced alteration of meibomian glands. Methods: Three μL of 1 N NaOH were applied under general anesthesia to the right eye of 6 8 week old wild-type (n = 5) and Smad3 (n = 10) mice to produce a total ocular surface alkali burn. Mice were killed and eyelid was processed for histology of meibomian glands at day 5, 10 and 20 post-treatment. HematoxilinEosin, oil red O staini and immunohistochemistory for α-smooth muscle actin were employed. Results: Histology showed extremely dilated lumen of the meibomian glands in alkali-burned tissue. The dilated lumen was filled with Oil red O-labeled meibum. Different from uninjured mebomian glands, dilated lumen was rapped with a multiulayer of flattened cells that was labeled with anti anti-αSMAantibody. Lacking Smad3 did not affect the pathology of the treated meibomian glands. Conclusions: Meibomian glnad cells underwent epithelialmesenchymal transition following ocular surface alkali exposure. Obstruction of the gland orifice might accumulate meibum, leading extreme dilation of the gland lumen. Smad3 signal might not be involved in EMT of meibomian gland cells in the pathological condition. Commercial Relationships: Shin Mizoguchi, None; Yuka Okada, None; Reiko Arita, None; Shizuya Saika, None