question: Which proteins in the cerebro-spinal fluid can be used for early diagnosis of Alzheimer's disease?
answer: CSF is a clear fluid that bathes and cushions the brain and spinal cord. Adults have about 1 pint of CSF, which physicians can sample through a minimally invasive procedure called a lumbar puncture, or spinal tap. Research suggests that Alzheimer's disease in its earliest stages may cause changes in CSF levels of tau and beta-amyloid, two proteins that form abnormal brain deposits strongly linked to the disease.