IL7 Receptor

The IL7 Receptor

Research Presentation from Dr Fiona McKay.

Transcript of Interview - The IL7 Receptor

RESEARCH PRESENTATION - THE IL7 RECEPTOR

FIONA MCKAY
I’m Fiona McKay, and I work at the Westmead Millennium Institute, on Multiple-Sclerosis research.

I think the really exciting thing that we’ve been working on is a gene called the IL7 receptor. Now don’t let that put you off, I know it’s a long term but what the IL7 receptor is, is it’s a gene that’s been found to be associated with MS, and researchers in our lab discovered that around about ten years ago and since then we’ve been trying to work out what it is that this IL7 receptor gene does to make you more susceptible to MS.

Well to tell you about what the gene does, I have to tell you a little bit about what MS is. T-cells of the immune system get activated inappropriately and they actually start to attack the brain and the spinal chord, and that’s what’s thought to do the neurological damage in the disease. Now, in a healthy immune system we actually do have cells that also are capable of attacking the brain and the spinal chord. Now, in a healthy immune system though we’ve got another subset of t-cells that are called regulatory t-cells and they police this process.

So what a regulatory t cell does is it roams around the circulation and it finds these t-cells that have the capacity to attack our own bodies, and it shuts them down completely. Now, regulatory t-cells are made in the thymus and um they’re actually made by another sub-set of immune cells called dendritic cells, and this is where the IL7 receptor comes in. So what IL7 receptor is, is it’s a little sensor on the surface of the dendritic cell and it receives signals from the thymus telling it to make regulatory t-cells. So, what we’ve discovered is that in a healthy immune system the dendritic cells receive these little signals through IL7 receptor and they make lots of regulatory t-cells, and they shut down autoimmune reactions. And that’s how the system should work.

So what we’ve found is that people who have the MS susceptibility variant of IL7 receptor have an impairment in this whole system. So the IL7 receptor is actually not working properly, it’s not receiving the signals into the dendritic cell and the immune system’s not getting the message to make these regulatory t-cells, and we think that that’s why the auto-immune cells are able to go and do the damage in the brain and the spinal chord.

People with MS don’t have enough of these regulatory t-cells that are able to shut down the autoimmune reactions. And that’s a problem because then these t-cells can go and attack the brain and spinal chord. So what we’d like to do is intervene in the process and somehow boost up the level of regulatory t-cells in people with MS so that they can shut down their auto-immunity.

So what we’re doing at the moment in the lab is we’re working on ways of making regulatory t-cells with a view to down the track being able to use them as a therapy. So the thought is we could actually make these regulatory t-cells and actually inject them in people with MS so that they can shut down their autoimmune attack on the brain and the spinal chord.

Regulatory t-cell biology has been a really hot area in immunology for the last ten years, and there’s actually been a lot of developments worldwide in regulatory t-cell biology, such that last year the first regulatory t-cells were actually injected into humans as a therapy for Graft versus Host Disease. So the area is coming along really quickly.