Immunolocalization of TNFα in the spinal cord of ALS patients. Expression in the cytosol of motor neurons was weak in the control spinal cord (a). ALS patients showed increased TNFα labeling in the motor neurons (d). Laser scanning confocal micrographs of immunofluorescence for TNFα (red) and ferritin (microglia, green) (b, e) or GFAP (astrocytes, green) (c, f) show upregulation of TNFα in the glial cells of ALS patients (e, f, arrows) compared to those of controls (b, c). Magnification: 40x. Spinal cords from sporadic ALS (five males and three females) and control patients with nondegenerative or nonneurological diseases (three males and three females) were used. Controls were patients with one of the following: cardiac failure, chronic sepsis, and CNS or non-CNS tumor. The mean age at death was 60 years (range 52–69) for ALS patients and 64 years (range 55–75) for controls. Duration of illness in ALS cases ranged between 10 and 60 months. All cases were autopsied within 8 to 15 hours from death. Tissues were fixed in formalin and embedded in paraffin.