MUC13 and infection: The glycocalyx that coats the apical surface of the intestinal lumen was thickened in response to infection, with an increase in the cell surface mucins, Muc4, Muc13 and Muc17. Moreover, we have clearly demonstrated that along with goblet cell hyperplasia observed during worm expulsion, there was an increase in the secretion of more highly charged mucins into the mucus barrier.