Cytokine production by mesenteric lymph nodes from naïve and Trichuris muris infected FVB (WT) and mdr1a-/- (PGP-KO) mice. Levels of Th1 [interferon (IFN)γ, A; interleukin (IL)-12p40, C] and Th2 (IL-13, D; IL-5, E) and the pro-inflammatory cytokine [tumor necrosis factor (TNF)α, B] were measured in mesenteric lymph nodes (MLN) following in vitro stimulation with Trichuris muris (T. muris) E/S antigen. MLN were isolated on day 19 post infection in T. muris infected groups. Data is shown as mean + SD for n = 5 animals in each group aP < 0.05; bP < 0.01.