FIG 6.

IL-25 induces clustering of Th9 cells proximal to lung dendritic cells. (A,C) Representative lung sections of CD11c-YFP expressing WT and CIKS KO mice (A) or CCL17-GFP reporter ‘WT’ (CCL17^+/−) and KO (CCL17^−/−) mice (C) after i.v. injection of in vitro differentiated, TdTomato-marked Th9 cells, followed 24h later by two i.n. administrations of IL-25 on successive days, analyzed the following day. (B,D) Quantification of TdTomato T cells and YFP (B) or GFP (D) cell densities in clusters, and total numbers of these cells in lung tiles for data from (A) and (C), respectively, based on counting cells in three sections of left lobule of the lung per mouse from three independent mice/experiments. Clusters defined as ≥ 3 T cells in close proximity to each other, which only occurred very close to (or ostensibly touching) dendritic cells. *p<0.05; **p<0.01; ***p<0.005.