Recently a demyelinating disease similar to MS that predominantly affects the spinal cord and optic nerves has been associated with a specific antibody (immune protein) in the blood. It was of some surprise that in this disease, neuromyelitis optica (NMO), the antibody was directed against a component of astrocytes, the supporting cells of the central nervous system (CNS) rather than myelin or the myelin producing cells, oligodendrocytes.
This challenges the long-held belief that demyelination must be secondary to a primary attack on this structure in MS and shows that withdrawal of supporting cells might cause secondary loss of oligodendrocytes and myelin. The group at the University of Sydney recently confirmed in autopsy specimens that astrocytes are floridly destroyed in NMO and that this results in death of oligodendrocytes and demyelination. They also showed that a different type of astrocyte damage occurs in MS and the predominant abnormality is a loss of processes around blood vessels and nerve fibres. They suspect that astrocyte damage contributes to disease in MS by reduction of support to oligodendrocytes (and hence demyelination) and also by impaired function at specialised nerve junctions.
In this project, Biyi Chen will explore the role of astrocytes in autopsy brain tissue from MS patients to determine whether astrocyte damage is preceded by disintegration of the supporting gel or matrix of the brain. This structure, within which all cells move and interact can be damaged in MS and we will determine whether this may be the cause of the astrocyte lesion in MS.
Updated: 30 June 2012
Updated: 02 January, 2011