Figure 2.

CK19-mediated transgene expression. A: Section of bladder from a 18-week-old CK19-hPAP transgenic mouse incubated with BCIP showing diffuse and uniform staining in urothelium and adjacent stroma. Muscle is not stained. B: Somniferous tubules and bladder from a nontransgenic mouse (top; arrow indicates bladder) and a CK19-TAg transgenic male at 13 weeks of age (bottom). The transgenic mouse bladder is distended and the basal portion is diffusely infiltrated by neoplastic cells. Original magnifications, ×100 (A) and ×1 (B).