Figure 2: The effects of the different LPS forms on IFNγ production in serum-containing and serum-free media. (a) The effects of S- and R-LPS on the IFNγ production in AIM-V serum-free media. Results from six independent experiments are shown. (b) The effects of normal and deacylated S-LPS from different E.coli strains on IFNγ production by NK cells. (c) The structures of repeating units of O-antigen of LPSs used in this work. Results from four independent experiments are shown.