Figure 5. Antigen and dose-dependent cytokine polarization of human iNKT cells.

(A) EC50 values (Ag concentration required to obtain half maximal cytokine response) were calculated for production of the indicated cytokines in response to each of the glycolipid agonists. Values are presented on a logarithmic scale, and EC50 values of IL-4 for C20:4, OCH, DFB, BB and AD compounds could not be calculated because IL-4 levels did not reach a plateau and were >10 µM. (B) To show variations in cytokine ratios depending on the analog concentration tested, IL-13/IFNγ ratios and IL-4/IFNγ ratios are presented on the bottom and top panel, respectively (calculated as explained in Materials and Methods). Note that ratios could be calculated only when IL-4 and/or IFNγ were detectable and the # symbol indicates ratios which could not be calculated. Concentrations of antigens are indicated as in figure 2A, with low concentrations tested for KRN7000, C20:2 and C20:4 (1.6, 12.5 and 100 nM, white background bars) and high concentrations of other analogs (156, 1250 and 10000 nM, gray background bars). Data presented in this figure were interpreted from results shown in Figure 2, and IL-13/IFNγ & IL-4/IFNγ ratios calculated for HDD3 and HDE3 clones with DCs are presented in supplementary Figure S6.