LEFT: Two-dimensional polyacrylamide gel of silver-stained proteins from 194 human ALS motor neuron cell bodies. The cells were isolated from the lumbar spinal cord of a 70 year-old female with a one-year history of sporadic ALS. This spot pattern closely resembles that observed for motor neuron cell bodies from control lumbar spinal cord. The acidic end of the gel is on the right. Two presumptive contaminants – cytokeratins (arrow) and GFAP breakdown products (arrowhead) – appear on this gel, but were not present on all 2D gels of human motor neuron cell bodies.

RIGHT: Two-dimensional polyacrylamide gel of silver-stained proteins from normal lumbar ventral roots of a 70 year-old individual. The large, densely stained area contains serum albumin. The acidic end of the gel is on the right.