Immunological Demyelination Triggers Macrophage/Microglial Cells Activation without Inducing Astrogliosis

Figure 2

Localization of GFAP-immunoreactivity by immunoelectron microscopy within the region of immunological demyelination 7 days following intraspinal injection of GalC antibodies plus complement proteins. (a) Lower magnification of (b) showing a GFAP-positive astrocyte and the nearby border zone between the normally myelinated and demyelinated region (hatched line). Note the lack of astrogliosis at the border zone. (b)–(g) Astrocyte (A) with GFAP-immunoreactivity (arrows) within the cytoplasmic compartment immediately adjacent to the nucleus and a GFAP-positive process (arrowhead). For comparison, (d) illustrates distal reactive astrocytes 1 mm rostral to the injury epicenter. Note the hypertrophied process and multiple branches (arrowheads). (h) High magnification with focus on GFAP-positive process (black*). Note multiple dark GFAP-positive parallel lines corresponding to intermediate filaments. Scale bars: (a) 5 μm; (b), (c), and (f) 2 μm; (d) 5 μm; (e) and (g) 1 μm; (h) 0,2 μm.