RT Journal Article SR Electronic T1 Essential functions of Runx/Cbfβ in gut conventional dendritic cells for priming Rorγt+ T cells JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e201900441 DO 10.26508/lsa.201900441 VO 3 IS 1 A1 Mari Tenno A1 Alicia Yoke Wei Wong A1 Mika Ikegaya A1 Eiji Miyauchi A1 Wooseok Seo A1 Peter See A1 Tamotsu Kato A1 Takashi Taida A1 Michiko Ohno-Oishi A1 Hiroshi Ohno A1 Hideyuki Yoshida A1 Florent Ginhoux A1 Ichiro Taniuchi YR 2020 UL https://www.life-science-alliance.org/content/3/1/e201900441.abstract AB Acquired immune responses are initiated by activation of CD4+ helper T (Th) cells via recognition of antigens presented by conventional dendritic cells (cDCs). DCs instruct Th-cell polarization program into specific effector Th subset, which will dictate the type of immune responses. Hence, it is important to unravel how differentiation and/or activation of DC are linked with Th-cell–intrinsic mechanism that directs differentiation toward a specific effector Th subset. Here, we show that loss of Runx/Cbfβ transcription factors complexes during DC development leads to loss of CD103+CD11b+ cDC2s and alters characteristics of CD103−CD11b+ cDCs in the intestine, which was accompanied with impaired differentiation of Rorγt+ Th17 cells and type 3 Rorγt+ regulatory T cells. We also show that a Runx-binding enhancer in the Rorc gene is essential for T cells to integrate cDC-derived signals to induce Rorγt expression. These findings reveal that Runx/Cbfβ complexes play crucial and complementary roles in cDCs and Th cells to shape converging type 3 immune responses.