Mechanisms of high-dose intravenous immunoglobulins in demyelinating diseases.

Administration of high-dose intravenous immunoglobulins has become one of the most successful new treatment regimens for demyelinating diseases. In a decade of molecular medicine, it came as a surprise that a natural blood product would prove effective in several disorders, including Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, multifocal motor neuropathy, and, probably, multiple sclerosis. Many experimental studies, both in vivo and in vitro, have shown that intravenous immunoglobulins can interfere with the immune system at several levels. In addition, intravenous immunoglobulins may promote remyelination in demyelinating disease associated with viral infections. At present, no single mode of action has been identified as the crucial mechanism, which leads us to suggest that multiple effects may act in concert.