Expression of arginine-metabolizing enzymes in IECs upon Giardia infection. Differentiated Caco-2 IECs were in vitro infected with Giardia trophozoites of three different assemblages (isolates WB (squares), GS (circles) and P15 (triangles)) and expression of arginine-consuming enzymes in host cells was assessed after 0, 1.5, 3, 6 and 24 h on the RNA level by qPCR in technical quadruplicates. The data is presented as fold change gene expression in arbitrary units on a logarithmic scale as compared to 0 h expression. GAPDH was used as reference gene. In total 12 different arginine-consuming genes and the control gene ccl20 were assessed for their expression. Note the changed scale for ccl20. adc, arginine decarboxylase; agat, arginine-glycine amidinotransferase; arg, arginase; asl, argininosuccinate lyase; ass, argininosuccinate synthetase; cat, cationic amino acid transporter; ccl20, chemokine (C-C motif) ligand 20; nos, nitric oxide synthase; oat, ornithine aminotransferase; oct, ornithine carbamoyl transferase; odc, ornithine decarboxylase.