A review of rabbit models of meibomian gland dysfunction and scope for translational research

Abstract

Dry eye disease (DED) is an emerging global health concern with meibomian gland dysfunction (MGD) being the most common subtype of DED. Despite being quite prevalent, the pathophysiological mechanisms governing MGD are poorly understood. Animal models for MGD can be a valuable resource to advance our understanding of this entity and explore novel diagnostic and therapeutic modalities. Although a lot of literature on rodent MGD models exists, a comprehensive review on rabbit animal models is lacking. Rabbits offer a great advantage over other animals as models for studying both DED and MGD. Rabbits have a widely exposed ocular surface and meibomian gland anatomy comparable with humans, which makes performing dry eye diagnostic tests possible using clinically validated imaging platforms. The existing MGD models in rabbits can broadly be classified as pharmacologically induced and surgically induced models. Most models show keratinization of the meibomian gland orifice with plugging as the final common pathway for developing MGD. Thus, understanding the advantages and disadvantages of each rabbit MGD model can help researchers choose the appropriate experimental plan based on the objective of the study. In this review, we discuss the comparative anatomy of the meibomian glands in humans and rabbits, various rabbit models of MGD, translational applications, unmet needs, and future directions in developing MGD models in rabbits.