Cell therapy
Stem cells and Multiple Sclerosis, MS
Multiple sclerosis (MS) is a neurological disease that affects the brain and spinal cord 1. The term sclerosis refers to the formation of plaques in the brain and spinal cord 1.
In MS, the patient’s own immune system attacks the myelin sheath that surrounds and protects nerve fibres in the central nervous system 2. Many widespread inflammatory changes result in hardening, or sclerosis, of nerve tissue. These plaques disrupt nerve signals from the brain to other parts of the body. The increased presence of white blood cells in the centres of the disease indicates an element of inflammation 2.
Symptoms can be very varied, but include physical, psychological and sometimes psychiatric problems 3. In Sweden, about 20,000 people have MS and about 1,000 new cases are diagnosed each year.
The causes of MS are not yet fully understood. The underlying mechanism is believed to be either of an autoimmune nature where the damage is caused by the immune system, especially T-cells, attacking the body’s own tissue 4 or a defect in the myelin-producing cells 5. Suggested causes include genetics and environmental factors such as viral infections 2.
There is currently no cure for Multiple Sclerosis.
There are medications that can slow down the progression of the disease. All types of medication affect the immune system and reduce inflammation in the central nervous system. Haematopoietic stem cell transplants have become an accepted treatment for some forms of MS. The Uppsala University Hospital specialises in treating MS with blood stem cell transplants:
https://www.akademiska.se/for-patient-och-besokare/ditt-besok/undersokning/ahsct/
This involves haematopoietic stem cell transplantation where the patient’s diseased immune system is knocked out with chemotherapy.
Patients then receive healthy blood stem cells, which can build a new immune system, through a transplant. Until 2019, more than 200 MS patients have been successfully treated with blood stem cell transplantation in Sweden:
https://www.forskning.se/2019/01/16/blodstamcellstransplantation-effektivare-an-bromsmedicin-vid-ms/
The treatment aims to reset the immune system so that it ceases to damage the brain.
Analyses of blood cells from MS patients who have received stem cell transplants confirm that the immune system can be effectively reset to a less reactive state 6.
In a retrospective multicentre study, Muraro et al. evaluated the long-term outcomes of patients who underwent stem cell transplantation as a treatment for MS 7. The study included 281 patients with MS treated between 1995 and 2006. The researchers used a clinical rating scale called the Expanded Disability Status Scale to assess the participants’ functional ability.
The study’s primary endpoints were overall survival and progression-free survival, which is the time the patient can live without the disease getting worse.
Of the patients with MS treated with stem cell transplantation, almost half (46%) were progression-free and overall survival was 93% at 5 years after transplantation.
Although stem cell transplantation is approved for MS, it is primarily for people with more severe MS where traditional therapies have not worked.
Referenser
- Faguy, K. Multiple Sclerosis: An Update. Radiol Technol 87, 529-550 (2016).
- Baecher-Allan, C., Kaskow, B. J. & Weiner, H. L. Multiple Sclerosis: Mechanisms and Immunotherapy. Neuron 97, 742-768, doi:10.1016/j.neuron.2018.01.021 (2018).
- Compston, A. & Coles, A. Multiple sclerosis. Lancet 372, 1502-1517, doi:10.1016/S0140-6736(08)61620-7 (2008).
- Weiner, H. L. Multiple sclerosis is an inflammatory T-cell-mediated autoimmune disease. Arch Neurol 61, 1613-1615, doi:10.1001/archneur.61.10.1613 (2004).
- Nakahara, J., Maeda, M., Aiso, S. & Suzuki, N. Current concepts in multiple sclerosis: autoimmunity versus oligodendrogliopathy. Clin Rev Allergy Immunol 42, 26-34, doi:10.1007/s12016-011-8287-6 (2012).
- Muraro, P. A. et al. T cell repertoire following autologous stem cell transplantation for multiple sclerosis. J Clin Invest 124, 1168-1172, doi:10.1172/JCI71691 (2014).
- Muraro, P. A. et al. Long-term Outcomes After Autologous Hematopoietic Stem Cell Transplantation for Multiple Sclerosis. JAMA Neurol 74, 459-469, doi:10.1001/jamaneurol.2016.5867 (2017).
