Fig. 1
Delivery of p40 to the small intestine and the colon using pectin/zein hydrogels. Fourteen-day-old mice were gavaged with hydrogels containing NHS-rhodamine-p40 at 10 μg/mouse and hydrogels without p40 (no-p40) as control. Mice were euthanized at indicated times after gavage. Soluble proteins from small intestinal and colonic mucosal tissues were prepared for examining fluorescent intensity (a). The NHS-rhodamine-p40 concentration in mucosal lysates was determined by comparing to the NHS-rhodamine-labeled concentration curve and presented as: μg p40/mg tissue lysates. Paraffin-embedded tissue sections were prepared for observing NHS-rhodamine-p40 using a fluorescent microscope (b). Tyrosine phosphorylated proteins in tissue lysates were immunoprecipited for western blot analysis of total EGFR. Total tissue lysates were used for western blot analysis with anti-β-actin antibody to confirm the equal amount of proteins used for immunoprecipitation. In a, * and # p < 0.05 compared to the small intestine (*) and the colon (#) of the no-p40 group. n = 3–5 mice for each group
