Figure 4.

FcεRI⁺ DCs, but not basophils, present antigens to T cells after exposure to HDM and induce Th2 immune responses. (a) OVA-AF647 uptake by FcεRI⁺DX5⁺ basophils (top) and FcεRI⁺DX5⁻ cells (bottom) in the LNs 3 d after the administration of OVA-AF647 alone or in combination with HDM. (b) OVA-specific naive CD4+ T cell proliferation induced by FcεRI⁺DX5⁺ basophils, FcεRI⁺DX5 cells, or MHCII⁺CD11c⁺ DCs sorted from the LNs of OVA+HDM-administered animals 1 or 3 d after antigen exposure. (c) Cytokine production by OVA-specific naive CD4⁺ T cell restimulated for 4 d with FcεRI⁺DX5⁺ basophils, FcεRI⁺DX5⁻ cells, or MHCII⁺CD11c⁺ DCs sorted from the LNs of OVA+HDM-administered animals 3 d after antigen exposure. (d) RT-PCR analysis of MHCII-associated chaperone proteins in FcεRI⁺DX5⁺ basophils, FcεRI⁺DX5⁻ cells, or MHCII⁺CD11c⁺ DCs sorted from the LNs 3 d after HDM administration. Data are representative of at least three independent experiments from four to six mice/group.