Enhancing Myelin repair
The Foundation has been contributing to a Project Grant titled “Enhancing Myelin repair in multiple sclerosis” at the Florey Institute of Neuroscience and Mental Health, VIC, led by Professor Trevor Kilpatrick.
In multiple sclerosis (MS) the protective sheath around nerves, known as myelin, is damaged and lost. This loss disrupts electrical impulses and exposes nerves to immune attack, leading to their death. Current MS therapies suppress the immune response but do not promote repair or prevent disease progression. Professor Kilpatrick and his team have shown that a protein known as Tyro3 improves myelin production and repair. The goal of this study was to establish how Tyro3 works, and the comparative benefit it is likely to provide. In an important finding, they have determined that another molecule called BDNF, which is also known to promote myelin repair, employs different signalling pathways to Tyro3, suggesting the two molecules could be used in combination for greater improvement.
In an unexpected but important finding, they have found that disruptions to myelin structure, such as observed in the absence of Tyro3, do not necessarily result in detectable changes in the speed of electrical impulses in nerve fibres. This finding is good news for the development of remyelinating therapies for MS, as it implies that myelin does not need to recover to pre-damage levels to have functional therapeutic benefit.
Professor Kilpatrick and his team have also found that the visual system is dramatically disrupted in the absence of Tyro3. This may be because of the loss of myelin, or it may be more directly because of the loss of Tyro3 in nerves. They are now looking to answer this question, as it may be that therapies designed to activate Tyro3 may also provide direct benefit to nerves. This is important as ultimately it is damage to nerves which leads to disability in MS.
Due to the many Melbourne lockdown periods, there have been unavoidable delays with this important work impacting Professor Kilpatrick and his team’s ability to be fully productive. Despite the challenges, final analyses are underway with completion expected within six months.