You may wonder why scientists and clinicians are in a race to find a biomarker in MS. If you’re not wondering, you probably should be. And to find the answer we must first understand what on earth a biomarker is and then wrap our heads around why they are important.
A biomarker (short for biological marker) is a biological measure that can be used as a simple indicator of health or disease status. Every biological system in our bodies has its own unique markers. For example, heart rate and blood pressure are markers for the cardiovascular system.
As a scientist, I see research in biomarker identity as extremely important, as biomarkers could one day provide a black and white answer to whether a person has, or is likely to develop, a disease.
In MS, biomarker research is very active, and a long list of candidates has been put forward by research groups around the world. Many of these candidates can be found in body fluids, particularly blood serum and plasma which are the liquid components of blood in which blood cells are suspended. Many biomarker candidates have also been suggested in cerebrospinal fluid (CSF) found in the spinal column. Let’s talk about each of these a little more.
First up, cytokines, namely a cytokine by the name of interleukin 17. Cytokines are a large family of proteins that help cells to communicate with one another. They orchestrate immune responses and direct the movement of cells towards sites of damage, infection and inflammation. Much evidence indicates that MS patients have increased levels of this cytokine in their blood and CSF, and this may be an indicator of MS disease activity.
Up next, neurotrophins, brain-derived neurotrophic factors in particular. This neurotrophin is produced by both nerve cells and by cells of the immune system. It has many beneficial effects on the survival of existing neurons, and also supports the growth of new neurons. Research shows that the blood levels of this neurotrophin appear to fluctuate with the occurrence of relapses, making it another possible predictor of disease activity.
And we can’t forget about myelin basic protein. Myelin injury has been a theory within the MS disease research community, and this process underlies another strong biomarker candidate. This protein and its fragments are clearly detected in the CSF of people, with its occurrence linked to clinical attacks.
Many more potential biomarkers make up a dauntingly long list, however, these examples illustrate a simple point. First understanding and then measuring biomarkers could potentially be important in the diagnosis of multiple sclerosis, determining how the disease will progress, and even predicting how the patient will respond to different treatments.
Let the race continue.