Fig 4. Submucosal injection as a pancolonic delivery of siRNA in mouse colon.
(A) Retention of FAM-labeled CHST15 siRNA within the submucosa of the normal mouse colon by differential interference contrast microscopy. Arrow indicated the site of injection. FAM-positive cells were clearly detected at higher magnifications (open squares). Original magnification, x100. (B) Diffusion of FAM-labeled siRNA in the whole normal mouse colon by stereoscopic microscopy. Lower panel showed fluorescence signals. Arrow indicated the site of injection. Non-injected colon was placed as a negative control. Original magnification, x7.3. (C) Concentrations of CHST15 siRNA in the normal mouse colon 4, 24, 48 and 144 h after a single submucosal injection.