Figure 6.

TSLP is required for basophil-mediated Th2 differentiation. Intracellular TSLP staining 3 days post papain immunization (a). Black histogram represents total LN cells, basophils, or DCs. Shaded histograms represent TSLP staining in peripheral blood basophils (basophil) or isotype control (total LN and DC). Gates indicate staining over isotype control. (b) 28F12 neutralizes TSLP dependent growth of NAG8/7 cells, but not IL-7 dependent growth of IxN/2b cells. TSLP neutralization in vivo does not effect basophil migration (c) or DC migration and maturation (d) after papain immunization. (e) Neutralization of TSLP in vivo inhibits Th2 differentiation. Percentages indicate gated population out of CD4⁺DX5^- cells. (f) Q-PCR analysis and cell survival (g) of CD4⁺ T cells stimulated in vitro with the indicated cytokines/neutralizing antibodies. WT indicates Balb/c and IL-4 deficient indicates IL-4Rα -/- mice in all plots except IL-4Rα in which IL-4 -/- mice were used. Survival percentages indicate live cells from indicated cultures versus live cells from cultures without added cytokines. Data are representative of multiple (n>3) experiments, error bars illustrate s.e.m. p values are calculated via the Student's t test, and represent comparisons to inactive papain immunizations for corresponding antibody treatments; **, p≤0.01; *, p≤0.05.