Figure 1. Goblet cell–specific expression of EGFP by human MUC5AC promoter in transgenic mice. Transgenic mice were produced by an injection of a construct composed of the 4.0 kb of the 5′ end of human MUC5AC promoter that was ligated to EGFP. Tissues were fixed and observed under fluorescent microscopy to locate the expression of EGFP as detailed in Methods. A: Differential interference contrast (DIC) picture of transgenic mouse conjunctiva. B: Frozen section of conjunctival tissue with EGFP expression in the same section. C: Merged picture of A and B.