Abstract
The primary reaction of the macrophage electrophoretic mobility test (MEM) and its modifications (viz. the interaction of myelin basic protein (MBP) and mononuclear cells) has been investigated. The binding of MBP to mononuclear cells is rather weak, and on incubation with mononuclear cells the MBP is proteolytically degraded. A fast process leads to fragments with mol. wts in the range 9000-14,000, followed by a slower process leading to peptides smaller than 5000. Both binding and proteolytic degradation are the same for mononuclear cells from cancer patients and from control individuals.