Infection of Giardia duodenalis (assemblage A) may cause diarrhea, with enhanced MUC2 gene expression in human colonic epithelial cells, via both the protease-activated receptor 2 (PAR2) that is activated by trypsin and giardia cysteine protease activity (CPs), by degrading chemokines; the above evidence was also confirmed though Ca2+ free and the inhibitor of the ERK1/2-MAPK cascade, which restrains the Muc2 transcription profile [123]. Here, F2RL1 is linked to infection.