BLP plus MDP induces RACs to express costimulatory molecules.

<p>(A) RACs were incubated for 48 h in, from left to right, medium alone or medium containing BLP or MDP or both, then were stained with monoclonal Abs against CD80, CD40, or ICOSL, and analyzed by flow cytometry. Negative control samples were stained with an isotype-matched control IgG Ab (empty filled). Numbers in each histogram represent mean fluorescence intensity values. One of three reproducible experiments is shown. (B) The antigen-specific uveitogenic T cell expansion induced by MDP plus BLP-pre-treated RACs is inhibited by anti-ICOSL and anti-CD80 Abs. T cells from in vivo IRBP1-20-primed B6 mice at day 12 were cultured with MDP plus BLP-pre-treated RACs and IRBP1-20 in the absence or presence of 10 μg/ml of anti-CD80, CD40, and ICOSL Abs either alone or in combination or their rat IgG2a, κ isotype control, then proliferation by the responder T cells were determined. C: Cytokine production of the antigen-specific uveitogenic T cells induced by MDP plus BLP-pre-treated RACs is inhibited by anti-ICOSL and CD80 Abs. The experimental paradigm was as in (B), but, after 48 h, cytokines in culture supernatants were measured by ELISA. The values are the mean ± SEM for three individual experiments. *<i>p<</i>0.05, **<i>p<</i>0.01 compared with control in one-way ANOVA.