BLOG | Biomarkers: What are they?
In most medical processes, the specialist who is examining us needs complementary tests to the initial physical check-up in order to rule out or corroborate the suspicion of a disease or to prescribe a specific treatment. For example, if we visit the endocrinologist because we want to lose weight, he will ask us for a blood test to know the level of glucose, haemoglobin and lipids in the blood, among others, to rule out diabetes.
The same is true with Alzheimer's disease. If a person comes to the consultation with memory complaints, we, the neurologists, in addition to doing the battery of neuropsychological diagnostic tests, we ask for imaging tests (brain resonance) and lumbar puncture to know if in the body of the person who visits us there are biomarkers compatible with Alzheimer's.
And what are these biomarkers? The brain and spinal cord are surrounded by a fluid called cerebrospinal fluid (CSF). This CSF is obtained by lumbar puncture. In this liquid there are substances that inform us about how the brain is. As in the case of the endocrinologist who requests glucose or lipid analysis, neurologists assess whether there is an accumulation of beta amyloid proteins and Tau proteins in the brain, the Alzheimer's biomarkers most accepted by the scientific and medical community.
The importance of research
As you know, Alzheimer's is very complex, and the scientific community knows that there are other biomarkers yet to be discovered that would inform the onset, predict its course and monitor the effect of drugs to treat it. In the same way, there are also other less frequent dementias than Alzheimer's, such as Lewy Body Dementia, which do not have biomarkers or are more difficult to determine.
It is in this phase that research takes on an essential role. Currently, the presence of biomarkers in the blood is being investigated, which would be easier to obtain than those obtained through a lumbar puncture to analyze the cerebrospinal fluid.
Among the objectives of the research carried out by Ace Alzheimer Center Barcelona, in collaboration with other entities and consortiums, is also to establish new useful biomarkers in both cerebrospinal fluid and blood for the early detection of dementias.
The largest collection of Alzheimer's samples
As we have said before, research becomes essential to understand how Alzheimer's originates and develops, and we can only do this by analyzing biomarkers from thousands of blood, cerebrospinal fluid and saliva samples donated altruistically by thousands of people in different phases of the disease.
Once we obtain these samples, they are organized and classified as if they were library books, cataloged according to different criteria. This library constitutes Ace's collection of samples, which, with more than 17,000 genetic samples with associated diagnoses, constitutes the world's largest repository of dementias.
But how can they be kept in good shape? Ace samples are kept in tubes at different temperatures in order to preserve them. They are needed from -80ºC freezers to -20ºC refrigerators and chambers, and without this equipment they could not be conserved to carry out genomic and biomarker research projects. These are very expensive equipment that requires an economic effort on the part of the laboratories and companies that store this type of material, but thanks to donations from manufacturing companies such as Telstar, Ace Alzheimer Center Barcelona can preserve thousands of samples in perfect condition, lead different research projects and share valuable information with other entities to make Alzheimer's history one day.
DR. ADELA ORELLANA
Laboratory manager at Ace Alzheimer Center Barcelona