Distribution of five clinically important neuroglial proteins in the human brain

• Published in: Molecular brain 2022-06, Vol.15 (1), p.1-52, Article 52
• Main Authors: Sjölin, Karl, Kultima, Kim, Larsson, Anders, Freyhult, Eva, Zjukovskaja, Christina, Alkass, Kanar, Burman, Joachim
• Format: Article
• Language: English
• Subjects: Age; Analysis; Atlases as topic; Biomarkers; Brain; Central nervous system; Cerebellum; Cerebral cortex; Cerebrospinal fluid; Disease; Enzyme-linked immunosorbent assay; Gene expression; Glial fibrillary acidic protein; Hydrolase; Hydrolase, ubiquitin carboxy terminal; Medicin och hälsovetenskap; Myelin; Myelin basic protein; Myelin basic proteins; Myelin proteins; Nervous system; Neurofilament proteins; Neuronal-glial interactions; Protein gene product 9.5; Proteins; Regression analysis; Spinal cord; Substantia alba; Tau; Tau protein; Ubiquitin; ubiquitin carboxy terminal; Ubiquitin carboxy-terminal hydrolase
• ISSN: 1756-6606; 1756-6606
• DOI: 10.1186/s13041-022-00935-6

Glial fibrillary acidic protein (GFAP), myelin basic protein (MBP), neurofilament light chain (NFL), tau and ubiquitin carboxy-terminal hydrolase L1 (UCHL1) are five neuroglial proteins that are used as CSF or blood biomarkers of tissue damage in the nervous system. There is incomplete knowledge of how the concentration of these proteins differs between anatomical regions in the CNS as previous studies have focused on gene expression or non-quantitative protein analyses, limiting the interpretability of these biomarkers. The purpose of this study was to create a map of the tissue content of these proteins in different regions of the CNS. The concentrations of the investigated proteins were determined with ELISA in post mortem tissue homogenates from 17 selected anatomical regions in the CNS from ten deceased donors aged 24 to 50 years. When appropriate, the protein concentrations were adjusted for post-mortem interval. In total, 168 tissue samples were analysed. There was a substantial variation in the concentrations of GFAP, MBP, NFL, tau and UCHL1 between different CNS regions. Highly myelinated areas of the CNS had tenfold higher MBP concentration than cerebral cortex, whereas tau showed an inverse pattern. GFAP, NFL and tau displayed an anteroposterior gradient in cerebral white matter. The cerebellum had low concentrations of all the investigated proteins. In conclusion, the tissue concentrations of GFAP, MBP, NFL, tau and UCHL1 were determined throughout the CNS. This information can be used as a reference when interpreting circulating levels of these biomarkers in relation to the extent and localisation of CNS-damaging processes.