Fig 1.

Covalent A^b/peptide complexes are expressed on the surface of DCs and retain the same T cell specificity as noncovalent complexes. (A) BM-derived A^bIi⁻ DCs, transduced with A^bβPCCVA-YFP and A^bβEp-CFP complexes, were stained with anti-CD11c-PE or YAe-biotin/SA-CyChrome (specific to A^bEp) mAbs and analyzed by FACS. YAe mAb was used to identify A^bEp because CFP is not detectable by FACS. A dot plot represents results obtained on CD11c-positive cells, gated as indicated. (B) Comparison of expression levels on transduced BM-derived A^bIi⁻ DCs vs. BM-derived DCs from A^bIi⁻ and A^bwt mice. Cells were stained with Y3P-biotin/SA-CyChrome mAb (specific to A^b) and analyzed by FACS. (C) TCR^Tg CD4⁺ T cells were incubated with irradiated BM-derived DCs expressing indicated covalent complexes. Incorporation of [³H]thymidine by proliferating T cells ± SD is shown. Data are representative of three independent experiments.