Deficiency of Dectin-2 attenuates the rLdpA–chitin complex-induced immune response.

(A) Recombinant LdpA–chitin complex (rLdpA, 10 μg; chitin, 100 μg) were administered intranasally to Dectin-2−/− and C57BL/6 mice three times. All animals were sacrificed 72 h after the last nasal administration, and samples were obtained. (B) The numbers of total cells, neutrophils, and eosinophils in BAL fluid were measured by flow cytometry. (C) KC/CXCL1 and CCL11/Eotaxin-1 protein levels in the BAL fluid were measured by ELISA. (D) IFN-γ, IL-4, and IL-5 secretion by spleen cells after ex vivo re-stimulation with or without 10 μg/mL rLdpA. (E) Levels of serum LdpA-specific IgG1, IgG2a, and IgE measured by indirect ELISA. Data are shown as the mean ± standard deviation (SD) (n = 5–10 mice/group). Each symbol represents an individual sample. *P P P t test.