Detection of tau proteins in normal and Alzheimer's disease cerebrospinal fluid with a sensitive sandwich enzyme-linked immunosorbent assay

J Neurochem. 1993 Nov;61(5):1828-34. doi: 10.1111/j.1471-4159.1993.tb09823.x.


Alzheimer's disease is a progressive degenerative dementia characterized by the abundant presence of neurofibrillary tangles in neurons. This study was designed to test whether the microtubule-associated protein tau, a major component of neurofibrillary tangles, could be detected in CSF. Additionally, we investigated whether CSF tau levels were abnormal in Alzheimer's disease as compared with a large group of control patients. We developed a sensitive sandwich enzyme-linked immunosorbent assay using AT120, a monoclonal antibody directed to human tau, as a capturing antibody. With this technique, the detection limit for tau was less than 5 pg/ml of CSF. Using AT8, which recognizes abnormally phosphorylated serines 199-202 in tau, the detection limit was below 20 pg/ml of CSF. However, with AT8, we found no immunoreactivity in CSF, suggesting that only a small fraction of CSF tau contains the abnormally phosphorylated AT8 epitope. Our results indicate that CSF tau levels are significantly increased in Alzheimer's disease. Also, CSF tau levels in a large group of patients with a diversity of neurological diseases showed overlap with CSF tau levels in Alzheimer's disease.

Publication types

  • Comparative Study

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Aged, 80 and over
  • Alzheimer Disease / cerebrospinal fluid*
  • Antibodies, Monoclonal
  • Blotting, Western
  • Child
  • Child, Preschool
  • Enzyme-Linked Immunosorbent Assay / methods
  • Humans
  • Middle Aged
  • Molecular Weight
  • Reference Values
  • tau Proteins / cerebrospinal fluid*


  • Antibodies, Monoclonal
  • tau Proteins