Blockade of IL-17 and IL-23R, but not IFN-γ, inhibits ETBF-induced colonic tumor formation in Min mice. (a) Methylene blue–stained representative samples of distal colons of mice colonized with ETBF for 5 weeks and treated with IL-17 and IL-23R blocking antibodies or isotype control antibodies. (b) Depiction of tumor number distribution by box-and-whisker plots in ETBF-colonized mice treated with isotype-matched antibodies (IgG + ET; experimental positive control) and ETBF-colonized mice treated with IL-17– (IL-17A + ET), IL-17– and IL-23R– (IL-17 + IL-23R + ET) or IFN-γ– (IFN-γ + ET) blocking antibodies after 5 weeks. Sham-inoculated mice served as an experimental negative control. Top, n = 24 for IgG + ET, 8 for IL-17 + ET, 14 for IL-17 + IL-23R + ET and 7 for sham. Bottom, n = 9 for IgG + ET and 11 for IFN-γ + ET. (c) Histopathology of distal colon tumors in Min mice colonized with ETBF for 5 weeks and treated with isotype control antibodies (left) or IL-17– and IL-23R–blocking antibodies (right). Two representative mice of 24 (isotype control) or 14 (IL-17–blocking and IL-23R–blocking antibody treated) per treatment group are shown. (d) Histopathology of distal colon of Min mice colonized with ETBF for 1 week and treated with isotype control antibody (center) or IL-17– and IL-23R–blocking antibodies (right). Left image shows the distal colon of a sham control Min mouse. Micrographs are representative of three sham control, five ETBF and isotype control antibody–treated and four ETBF, IL-17– and IL-23R–neutralizing antibody–treated mice.