News Releases & Research Results The study develops a high-precision assay to determine the proteins specific to ALS ―Research marks the beginning of an innovative diagnosis of ALS in the future―

The results of collaborative research led by Professor Takahiko Tokuda of the Department of Molecular Pathobiology of Brain Diseases, Kyoto Prefectural University of Medicine, and Associate Professor/Lecturer Takashi Kasai of the Department of Neurology, Kyoto Prefectural University of Medicine and others.

• Using the ultrasensitive assay, Simoa (Single molecular array: a method to quantify traces of protein), detected and quantified TDP-43 (*1), NfL (*2), and tau (*3) which accumulate in the brain and spinal cord of patients with amyotrophic lateral sclerosis (ALS) in human cerebrospinal fluid and blood.
  The research successfully provided a comprehensive measurement of all these proteins for the first time.
  (*1): The abbreviation for TAR DNA-binding protein 43kDa. It is an RNA-binding protein that is normally present in the nucleus and regulates transcription of DNA to RNA.
  (*2): The abbreviation for neurofilament light chain. It is a cytoskeletal component abundant in the neurites of neurons.
  (*3): A protein that binds to neuronal microtubules.
• Compared to the control patient group, significantly higher level of TDP-43 and NfL was found in the cerebrospinal fluid and blood of patients with ALS. It became clear that biochemical diagnosis of ALS, which was previously thought to be impossible, can be made precisely by measurement of the combination of TDP-43 and NF-L in the cerebrospinal fluid.
• In addition, the study revealed that NfL in the blood and cerebrospinal fluid is most highly correlated with the life prognosis of patients with ALS.
• These findings showed that these biochemical biomarkers are available to precisely and rapidly make ALS diagnosis and prognosis determination, which were previously only based on clinical symptoms.

The results of this research were published in Annals of Clinical and Translational Neurology, an American online journal, on November 11(US time).

Kasai T., et al. Combined use of CSF NfL and CSF TDP-43 improves diagnostic performance in ALS Annals of Clinical and Translational Neurology
DOI：10.1002/acn3.50943