Figure 1.

IL-1β induces dramatic changes in astrocyte phenotype. a, Primary human astrocyte cultures exposed to 10 ng/ml IL-1β for 24 hr, or left untreated (Ctrl), were imaged by scanning electron microscopy. Scale bar, 20 μm. Treated cells developed a spherical cell body and multiple highly branched processes, terminating in prominent microvilli (inset; scale bar, 3 μm). The experiment shown is representative of three experiments using astrocytes from three different brains. b, Confocal z-series of astrocytes treated as in a and stained with phalloidin were subjected to software rendering to illustrate the arrangement of F-actin in these cultures. Individual images from the z-series stacks are shown directly below the renders. Scale bar, 40 μm. The experiment illustrated is representative of three experiments using astrocytes from three different brains.