A conversation about MS Research

MS Awareness Week 2025 in the UK is April 28th to May 4th, and this year’s theme is “MS Conversations”, so let’s have a conversation about the animals still being used in order to try and benefit patients like me.

What is MS?

Multiple sclerosis (MS) is a progressive disease affecting the brain and spinal cord, in which the immune system damages myelin, the coating of nerve fibres, leaving scars known as lesions or plaques. Messages travelling along nerve fibres can slow down, become distorted, or not get through at all, and, it can also damage the actual nerve cells too. Nerve damage accumulates over time and causes the increasing disability that people with MS experience over their lives.

More than 130,000 people in the UK have MS, and no two of us have the same range and severity of symptoms, even if we’re closely related. MS is not inherited, but family members do have a slightly higher risk of developing it.

What causes it?

What causes MS is still not clear, and there is continuing research into its causes. A combination of genetics and other factors in the world around us seem to set it off. A lack of sunshine (and Vitamin D) may play a part, alongside infection by certain common viruses like Epstein Barr Virus (EBV), smoking, obesity and long-term exposure to certain environmental chemicals.

Which animals are used in MS Research?

MS doesn’t occur in other animals, but an approximation of it is commonly induced in them, most often in mice, as Experimental Autoimmune Encephalitis, or EAE, which can cause severe suffering. EAE in mice is a group of diseases with some similarities to MS, but with limited relevance to the disease in humans and although many drugs have shown promise in mice, very few have done the same for humans.

Zebrafish are now being increasingly used in disease research. They are smaller than mice, arguably not as cute, cheaper, and easier to manipulate genetically due to their relatively large eggs and embryos. Their babies also develop outside the mother’s body and are quite transparent so molecular and cellular changes can be seen in real-time, often in the whole living animal.

A conversation about switching from mice to zebrafish

Recently, there have been media stories about zebrafish in MS research and this has been getting the hopes up of members of the MS community in the forums to which I belong. But is the research really as promising as the journalism makes it out to be, or are researchers developing yet another animal model that will have the same limited relevance as inducing MS like symptoms in poor mice?

Why zebrafish?

In the first week of zebrafish’s life, myelination, the development of the insulation of the nerve fibres to help signals travel quickly, happens rapidly, which shortens the time needed for research compared with mice. Drug testing using zebrafish can be done more quickly and efficiently because of the high number of babies from a single mating in these little fish. Because fish embryos develop ex utero, molecules and genes involved in vertebrate myelination can be identified more quickly and cheaply.

What do we really need?

MS is an incredibly variable heterogeneous disease. It is important to remember that there is no single animal ‘model’ that can reflect the entire spectrum of heterogeneity of MS and this research field lacks a focused disease model for progressive MS completely. This means that multiple, equally heterogenous human-based models are required to understand the full spectrum of disease mechanisms in order to treat and hopefully prevent it happening in future.

Instead of trying to ‘humanise’ the physiology of mice or zebrafish to explore opportunities to prevent the progression of MS and repair the damage caused by it, should we focus our resources instead on understanding the human fundamentals of why it continues to progress in many patients and how this may be addressed?

Organoids derived from tissue donated by patients are now revealing the basis of the varied clinical expressions of MS, and how and why we all differ so greatly in the speed and the extent of our disease progression.

If you would like to take part in research, then or even donate tissue or organs after your death, then please do consider the NHS advice and have those important conversations about it with your loved ones.

Learn more about tissue donation with the NHS