Biomarkers in cerebrospinal fluid sediments

Cerebrospinal fluid (CSF) biomarkers for neurodegenerative diseases have been extensively studied over the years. However, CSF samples are routinely centrifuged, and the resulting sediment or pellet is typically discarded to remove cellular debris and high-density particles. This standard practice raises a critical question: could these discarded sediments harbour potential biomarkers relevant to the diagnosis and prognosis of certain brain diseases? In this study, we analysed CSF pellets from various cases and identified, entrapped among undetermined remnants, brain-derived structures such as wasteosomes and psammoma bodies. Furthermore, we observed that disease-relevant proteins can become deposited in the sediment, as is the case for both tau and A{beta}42 in Alzheimers disease or tau in progressive supranuclear palsy disease. These findings suggest that some potential biomarkers might accumulate or be hidden in the sediment and, taken as a whole, the results underscore the need to broaden the scope of biomarker research. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=141 SRC="FIGDIR/small/657984v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@1d5b55corg.highwire.dtl.DTLVardef@175ae02org.highwire.dtl.DTLVardef@f30e42org.highwire.dtl.DTLVardef@12d326b_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstractC_FLOATNO C_FIG