Keratinisation Status and Cytokeratins of the Human Meibomian Gland Epithelium

The study investigated the keratinisation status and cytokeratin composition of the human Meibomian gland (MG) epithelium, which is crucial for ocular surface health. Using conjunctival specimens from 10 older body donors, the research found that the MG shares structural and embryological similarities with hair follicles, particularly in its keratinisation patterns. The study revealed that the MG epithelium expresses skin keratin CK10, which diminishes along the central duct, while filaggrin persists in the duct's superficial layer. CK14 was consistently expressed in the basal cell layer. These findings suggested that the MG can be considered a "hair without a hair shaft," with all parts showing signs of keratinisation. The study concluded that hyper-keratinisation is a typical event in obstructive Meibomian gland dysfunction (MGD), contributing to evaporative dry eye.