Rabbit Polyclonal Antibody to NF-H
Cat# RPCA-NF-H

      Neurofilaments are the 10nm or intermediate filament proteins found specifically in neurons, and are composed predominantly of three major proteins called NF-L, NF-M and NF-H, though other proteins may also be present. NF-H is the neurofilament high or heavy molecular weight polypeptide and runs on SDS-PAGE gels at 200-220 kDa, with some variability across species boundaries. The protein is in reality much smaller in molecular size, about 110kDa (1,2). The unusual SDS-PAGE mobility is due partly to a very high content of charged amino acids, particularly glutamic acid rich regions, and the non-phosphorylated form runs on SDS-PAGE at about 160kDa. The predominant type of NF-H is the axonal form which is heavily serine phosphorylated on 40 or more tandemly repeated lysine-serine-proline (KSP) containing peptides (3-5). The phosphorylation of these peptides results in considerable further retardation on SDS-PAGE gels, so the heavily phosphorylated axonal form runs at 200-220kDa with some species variability. Antibodies to NF-H are useful for identifying axonal processes in tissue sections and in culture. NF-H antibodies can also be useful in visualizing neurofilament accumulations seen in many neurological disorders, such as Amyotrophic Lateral Sclerosis (also known as Lou Gehrig’s disease), Alzheimer’s disease and following traumatic injury. The phosphorylated axonal form of NF-H usually referred to as pNF-H, can be detected in blood and CSF following a variety of damage and disease states resulting in axonal compromise, and antibodies such as this can be used to used to quantify such ongoing axonal loss (e.g. 6-8).
      The RPCA-NF-H antibody was raised against biochemically isolated NF-H purified from bovine spinal cord (9). This preparation is dominated by axonal forms of NF-H which are heavily phosphorylated on the multiply repeated NF-H KSP type sequences, and this antibody reacts very strongly with these phosphorylated repeats. Reactivity with non-phosphorylated KSP sequences is orders of magnitude weaker, similar to other characterized antibodies to NF-H (5). In most species there is some cross-reactivity with the phosphorylated KSP sequences found in the related neurofilament subunit NF-M which are similar but not identical to those of NF-H. The antibody recognizes phosphorylated NF-H strongly in all mammals tested to date and also in chicken. RPCA-NF-H recognizes neurofilaments in frozen sections, in tissue culture and in formalin fixed sections. We also supply three mouse monoclonal antibodies and a widely used chicken and goat polyclonal antibodies made to the same immunogen, MCA-NAP4, MCA-9B12, MCA-AH1, CPCA-NF-H and GPCA-NF-H. Mouse select image above left for larger view.