Using Single-Cell RNA Sequencing, Scientists Find That Immune Cells in CSF Become Dysregulated As We Age Normally and Are Drastically Altered in Those with Cognitive Impairment Such As Caused by Alzheimer’s Disease; Article Published in Cell

The reason your three-pound brain doesn’t feel heavy is because it floats in a reservoir of cerebrospinal fluid (CSF), which flows in and around your brain and spinal cord. This liquid barrier between your brain and skull protects it from a hit to your head and bathes your brain in nutrients. But the CSF has another critical, if less known, function: it also provides immune protection to the brain. Yet, this function hasn’t been well studied. A Northwestern Medicine study of CSF has now discovered its role in cognitive impairment, such as Alzheimer’s disease. This discovery provides a new clue to the process of neurodegeneration, said study lead author David Gate, PhD, Assistant Professor of Neurology at Northwestern University Feinberg School of Medicine. The study was published December13, 2022 in Cell. The open-access article is titled “Cerebrospinal Fluid Immune Dysregulation During Healthy Brain Aging and Cognitive Impairment.” The study found that, as people age, their CSF immune system becomes dysregulated. In people with cognitive impairment, such as those with Alzheimer’s disease, the CSF immune system is drastically different from that in healthy individuals, the study also discovered.