Neuromyelitis optica (NMO) is a rare autoimmune disease that was historically thought to be a type of multiple sclerosis (MS) and was often diagnosed as MS. However, recent discoveries indicate that NMO and MS are distinct diseases and should be treated with different medications. In people with NMO, a specific antibody has been identified that is not present in all people with MS. This antibody targets the immune system against a receptor in the brain called aquaporin-4 and has been shown to play an important role in the disease process of NMO. However, there are some people that do not have this “marker” but still show clinical symptoms similar to those of NMO.
Mr Siu’s project, under the supervision of Dr Parratt, aims to identify other antibodies that may be present in this group who do not show evidence of the aquaporin-4 antibody but who still show symptoms similar to NMO. This project will help lead to a better understanding of the mechanisms in these disorders that lead to loss of myelin from the nerves (the same process that occurs in MS) by identifying the target of the immune response. This, in turn, may allow the narrowing of the search to find the targets that are destroyed by the immune system in MS and how this leads to demyelination.
A cohort of approximately 100 serum samples from patients with NMO or similar diseases from a spectrum of related disorders (NMO spectrum disorders) has now been processed for analysis. Importantly, highly sensitive cell-based assays have established that these patients do not have the aquaporin-4 antibody. Mr Siu has now conducted his initial round of analysis of the samples and have identified several distinct binding profiles of antibodies. These people have been classified into a ‘variant’ NMO group as they exhibit novel patterns of binding that are different to those observed in classical NMO. A further round of analysis is now underway to more precisely specify the target of these potential novel antibodies.
Updated: 24 April 2015
Updated: 02 January, 2015