Fig. 6. T. gondii infection induces activation of conventional PKC. (A) Macrophages were infected with live T. gondii (5:1) or stimulated with media (m), STAg (50 µg/ml) or LPS (100 ng/ml) for the times indicated, then whole cell lysates were collected and fractionated by high-speed ultracentrifugation. Membrane fractions were used to immunoblot for PKC and PKCß as noted. Activation of PKC isoforms is determined by translocation to the membrane contained in the pellet fraction. (B) Densitometry of immunoblots in A, where data are represented as fold change over media-treated controls. Results are representative of seven experiments in which T. gondii induced a significant (P0.03) accumulation of both isoforms of PKC in the pellet fraction.