Qualification of a Neurology 2-Plex B (Nf-L, GFAP) Quanterix Simoa® Assay Using a Novel Approach

Purpose / Objective

• Biomarkers associated with neurodegenerative diseases and traumatic brain injuries,
  including Nf-L (Neurofilament light) and GFAP (Glial fibrillary acidic protein) have been
  identified as potential prognostic tools.
• Decreases in GFAP have also been reported in Down’s Syndrome, schizophrenia, bipolar
  disorder, and depression. Quanterix Neurology 2-Plex B (N2PB) Assay Kits measure both
  Nf-L and GFAP simultaneously in human serum, plasma, and CSF matrices in the fully
  automated Simoa® HD-X instrument.
• To qualify the method quantitative ranges in each matrix, high concentrations of proteins are
  required to achieve the necessary ranges, while maintaining the matrix integrity. However,
  obtaining reference material for both analytes with a high concentration to prepare controls
  in each matrix was not an option.
• A novel approach was utilized when, during screening of individuals, a high endogenous
  concentration for both Nf-L and GFAP was observed in one human CSF individual. The
  CSF individual was used to prepare controls in human serum, plasma, and CSF to
  qualify the assay successfully on the Simoa® instrument.