Theories concerning the cause of multiple sclerosis thus far advanced have failed to withstand experimental investigation or to lead to a suitable diagnostic test. A theory that has recently gained attention is centered about the postulation that an enzyme capable of breaking down myelin is related in some way to the pathologic process. Brickner1 devised a method to test this concept. He incubated fresh sections of rat spinal cords with blood plasma from patients with multiple sclerosis and from other persons. After suitable staining these sections were compared microscopically. The plasma of both patients with multiple sclerosis and normal subjects proved to have a destructive action on the cord, but Brickner concluded that this action was greater when plasma from the patients was used, and suggested that a lipase was responsible for the destruction.
Weil and Cleveland2 repeated these experiments and concluded that the deviation from normal was