pNF-H (Nfh, NEFH) ELISA Version 1 Cat# ELISA-pNF-H-V1

      Neurofilament subunit NF-H is one of the three so-called neurofilament triplet proteins which are major structural components of neurons. These proteins are particularly heavily concentrated in the axons of large projection neurons, where they clearly occupy the majority of the cytoplasm. The NF-H protein has an unusual C-terminal region which includes dozens of peptides based on the sequence lysine-serine-proline (KSP in the single letter amino acid code). In axons these KSP sites are heavily phosphorylated on the serine residues, while the form of NF-H in dendrites and perikarya is not normally phosphorylated (1,2). In consequence the KSP phosphorylated form of NF-H, usually referred to as pNF-H, is an axon specific form. We have developed sensitive ELISA kits to accurately quantify levels of the pNF-H protein. The protein is abundant and resistant to proteases so that, after axonal injury or degeneration, pNF-H can be readily detected with an ELISA such as this one. A variety of serious damage and disease states are associated with axonal compromise, such as amyotrophic lateral sclerosis, multiple sclerosis, traumatic brain injury and traumatic spinal cord injury. A growing list of peer reviewed publications make use of this and similar assays to monitor ongoing axonal loss associated with these and a variety of CNS damage and disease states. The first version of the assay utilized two affinity purified polyclonal antibodies, a chicken for antigen capture and a rabbit for detection, and has been described in peer reviewed publications (3,4). This assay is marketed by EnCor and several other vendors. We also developed and market this second generation pNF-H assay using two mouse monoclonal antibodies, although the first generation assay is also available, see ELISA-pNF-H-V1. This second generation assay has also been described in a peer reviewed publication (5). The manual for this kit can be downloaded here.

1. Sternberger LA, Sternberger NH. Monoclonal antibodies distinguish phosphorylated and nonphosphorylated forms of neurofilaments in situ. PNAS 80:6126-6130 (1983).
2. Lee VM et al. Identification of the major multiphosphorylation site in mammalian neurofilaments. PNAS 85:1998-2002 (1998).
3. Shaw G et al. Hyperphosphorylated neurofilament NF-H is a serum biomarker of axonal injury. Biochem. Biophys. Res. Commun. 336:1268-1277 (2005).
4. Petzold, A. and Shaw, G. Comparison of two ELISA methods for measuring levels of the phosphorylated neurofilament heavy chain. J. Immunol. Methods 319:34-40 (2007).
5. Boylan K et al. Phosphorylated neurofilament heavy subunit (pNF-H) in peripheral blood and CSF as a potential prognostic biomarker in amyotrophic lateral sclerosis. J. Neurochem. 111:1182-91 (2009).