Figure 5. APC-IDENs promote tumor growth by inducing CCR6⁺CD4⁺Th17⁺ cells.

(A–C) APC^min/+ mice at six weeks of age were gavaged with IDENs once every three days for eight weeks. (A) Number and size of tumors and H&E-stained sections from 3-month-old APC^Min/+ mice. (B) Mice were injected intraperitoneally (i.p.) with 50mg/kg of 5’-bromo-2’-deoxyuridine (BrdU) in PBS 24 h before small intestine harvest. BrdU antibody–stained small intestine sections. (C) A sectioned tumor was stained with anti-phospho-ERK antibody (red) or phospho-STAT3 (red) and E-cadherin (green). The data (A) represent means ± SEMs (n = 8). ^*p < 0.05, ^**p < 0.01 (Student’s t-test).

(D) FACS analysis of IL-17A⁺ on CCR6⁺CD4⁺ T cells and real-time PCR for cytokine mRNAs in LPL CCR6⁺CD4⁺ T cells. The data represent means ± SEMs (n = 5). ^*p < 0.05, ^**p < 0.01 (Student’s t-test).

(E–G) APC^min/+ mice gavaged with IDENs were treated with an anti-IL17A antibody or isotype. Representative photomicrographs of HE-stained colon sections (E), immunofluorescent staining of colon sections with anti-E-cadherin and Ki67 (F), and number of tumors (G).