Figure 3.

Immunohistochemistry Staining of the H2B-GFP/K5tTA Mouse Meibomian Gland LRCs at 56-Day Doxycycline Chase

(A) PPAR-γ was immunolabeled to identify lipid-producing meibocytes and confirm that LRCs (yellow arrowhead) are undifferentiated.

(B and C) K6 immunostaining co-localized LRCs with the terminal ends of the ductal epithelium (B) while K5 was found expressed in the entire meibomian gland epithelium (C).

(D) The overlay illustrates co-localization of K5⁺ and K6⁺ epithelial keratins in the meibomian gland and palpebral conjunctiva.

(E and F) A small subpopulation of LRCs were observed to express K6 (blue arrowhead), which indicated that a separate population of unipotent progenitors may exist to renew the duct.

(G and H) The majority of LRCs are K6⁻ (yellow arrowhead).