Figure 5. AIRE Interacts with AID in GC B Cells.

(A and B) Imaging flow cytometric analysis of AIRE and AID in tonsillar IgD⁻CD38⁺ GC B cells of a healthy donor. Bars: 7 μm (A). The results represent 3 donors.

(C and D) Co-IP of AIRE and AID in tonsillar CD19⁺ total, IgD⁺ naive and FGC and CD19⁺IgD⁻ GC and memory B cells of a healthy donor, and in splenic CD19⁺ B cells of a B6 mouse after 3 doses of immunization with SRBCs. The results are representative of tonsils of 4 donors and spleens of 3 mice.

(E) The domain structures of recombinant WT and mutant human AIRE and AID molecules. Dotted lines indicated the deleted regions in the mutant proteins.

(F) Co-IP of WT AID and WT or mutant AIRE in HKB-11 cells 24 h after transfection of plasmid(s) encoding WT AID and WT or mutant AIRE proteins.

(G) The domain structures of recombinant WT and mutant human AID proteins.

(H) Co-IP of WT AIRE and WT or mutant AID in HKB-11 cells 24 h after transfection of plasmid(s) encoding WT AIRE and WT or mutant AID proteins. The results in E and G are representative of 3 experiments.

(I) Flow cytometric analysis of IgA CSR in Aire^−/− CH12 cells (clone 69) transfected with a plasmid expressing either WT (Aire^WT-GFP) or CARD-deficient (Aire^ΔCARD-GFP) AIRE-GFP and treated with medium (Control) or anti-CD40, TGF-β and IL-4 for 3 d. The results represent 3 experiments.