PKR mediates CD40-induced autophagy upregulation and CD40-induced recruitment of LC3 around <i>T. gondii</i>.

<p><i>A</i>, HmCD40-RAW 264.7 cells were transiently transfected with either WT-PKR or DN-PKR. After 48 h, cells were transfected with tfLC3 followed by incubation with CD154 for 4 h. Monolayers were fixed and monitored by fluorescent microscopy for the number of autophagosomes (yellow) or autolysosomes (red). Autophagosomes and autolysosomes in CD154-stimulated cells that express WT-PKR are shown by arrowheads and arrows respectively. <i>B</i>, HmCD40-RAW 264.7 cells were transiently transfected with either WT-PKR or DN-PKR. After 48 h, cells were transfected with LC3-EGFP followed by incubation with CD154 overnight. Cells were challenged with transgenic RH tachyzoites that express RFP. 5 h post challenge, accumulation of LC3 around the parasite was examined by fluorescent microscopy (arrowheads). Results are shown as the mean ± SEM and are representative of 3 independent experiments. **p<0.01, ***p<0.001.