Cytokines and transcription factors expressed by inguinal lymph node CD11c+dendritic cells activate Th17 cells. (A) BALB/c wild type (WT) mice were immunized by the intraperitoneal (i.p.) and subcutaneous (s.c.) routes and at 24 hours spleen and inguinal lymph node (LN) were harvested and CD11c+ dendritic cells (DCs) sorted and cultured with TCR-Tg 5/4E8 CD4+ T cells. Supernatants were assayed for IFNγ and IL-17 by enzyme-linked immunosorbent assay. (B) RNA isolated from CD11+ DCs from i.p. spleen and s.c. inguinal LN at 6 hours (p19) and 12 hours (p40, IL-6, IL-1β, and TGFβ) after immunization was used to assess RNA transcripts. Bar graph represents the relative fold increase in transcript expression. CD11c+ DCs from nonimmune spleen and inguinal LN were used to calculate the relative fold increase in cytokine RNA expression. (C) BALB/c WT and p19−/− were i.p. and s.c. immunized. RNA was isolated from i.p. spleen and s.c. inguinal LN on day 5 and assessed for mRNA transcripts for transcription factors. Bar graph represents relative fold increase in transcription factors from s.c. inguinal LN (left panel) and i.p. spleen (right panel). Nonimmune spleen and inguinal LN were used to calculate the relative fold increase in transcription factor expression. Data are presented as mean ± standard deviation (n =3 to 6) *P <0.05. IFN, interferon; IL, interleukin; TGFβ, transforming growth factor beta.