Interferon Regulatory Factor 4-Dependent Conventional Dendritic Cells Coordinate Th2 Cell Induction.

<p><b>(A)</b> Antigen-presenting cells as a proportion of total MHCII+ cells in the lungs of infected mice. <b>(B)</b> MHCII expression by CD11b/c+ cells from mice 14 days post-infection with KN99α. Isotype refers to CD11b/c+ cells from wildtype mice stained with a rat IgG2b antibody of irrelevant specificity. <b>(C)</b> Quantification of pulmonary CD4+ Foxp3- CD44+ pulmonary Th cells. <b>(D)</b> Biexponential plot of CD4+ Foxp3- cells, indicating the absence of antigen-specific (CD44−, Cda2−) cells in the lungs of CD11c-cre MHCII mice infected with KN99α. <b>(E)</b> IRF4 expression by CD11b+ cDC from lungs of CD11cre IRF4 fl/fl or wildtype mice 14 days post-infection with KN99α. Isotype refers to CD11b+ cDC from wildtype mice stained with a rat IgG1 antibody of irrelevant specificity. <b>(F)</b> Geometric mean fluorescence intensity of CD11b+ cDC in from the lungs of infected CD11c-re IRF4 fl/fl mice. <b>(G)</b> Quantification of monocytes and dendritic cell subsets from the lungs of mutant or wildtype mice infected with KN99α. <b>(H)</b> Quantification of IL-5+ IL-13+ antigen-specific Th2 cells contained in the lungs of mutant or wildtype mice 14 days post-infection with KN99α. Data are presented as mean +/- standard error. * = <i>P</i> < 0.05, *** = <i>P</i> < 0.0005, and n.s. = not significant by Mann-Whitney <i>U</i>. Cda = chitin deacetylase, Flt3L = fms-like tyrosine kinase 3 ligand, MHC = major histocompatibility complex, cDC = conventional dendritic cells, IRF4 = interferon regulatory factor 4.