Figure 4.

Mouse brain temporal lobe of the cortex region stained for the microglial marker, Iba1: Cross sections of brain tissue injected with PBS control (A,C), and Stx2a (7 ng) B,D; (A,B), 48 h, (C,D) 72 h post-injection. Compared to controls at 48 h, brains of mice injected with Stx2a show an increase in the intensity of Iba1 staining of microglial cell bodies and processes (red arrows). At 72 h post-injection with Stx2a, morphologic change from the ramified (resting stage) characterized by long branching processes, to the activated macrophage-like globular structure displaying few processes and a more intensely stained cell body (D, green arrows) is observed. Scale bar represent 50 μm. Insert, entire brain scan where orange arrow indicates approximate position of the magnified image (n = 4).