Figure 6. ORO staining for lipid during meibomian gland development at different time points. Consistent with PPARγ, ORO staining was absent at E18.5 (A) and P0 (B). Lipid production was first detected at P3 (C) within the central region of the developing duct. At P5 (D) and P8 (E), ORO staining continued to be limited to the inner core of the developing duct. After eyelid opening at P15 (F), ORO was present in the acini of the mature gland.