Figure 5.

Direct-presentation requires cellular protein synthesis. WT3 cells were treated with cycloheximide for 1 hr prior to electroporation with ovalbumin (OVA). Cells were then treated for an additional 5 hr with cycloheximide (CHX) before being washed (b) or fixed (a). Cells were then incubated overnight with B3Z cells and then stained with 5-bromo-4-chloro-3-indolyl β-D galactopyranoside (X-gal). Each panel is representative of four experiments. Fixed and unfixed cells are presented on different panels because the stimulator to responder ratio was different. The same number of stimulator cells were initially plated, but a greater number of cells were lost in the fixed wells than were lost in the unfixed wells. Error bars represent the standard error of the mean.