No obvious evidence of caspase-3 activation in T40-AV-infected astrocytes. Western blot analysis with a specific antibody to cleaved caspase-3 (Cell Signaling Technology, Beverly, MA). No clear band of cleaved caspase-3 (A) was observed in cell lysates from astrocytes infected with T40-AV for different lengths of time, unlike the astrocytes treated with staurosporin for 4 hr.