The neurofibrillary tangles (NFT) are neuronal inclusions that are the hallmark lesions of Alzheimer’s disease (AD).  These tangles are made up of paired helical filaments (PHF).  The PHF are highly insoluble structures and are known to be composed of a highly phosphorylated form of the microtubule-associated protein tau and may contain associated lipid. Insoluble NFT which were extracted in boiling sodium dodecyl sulfate, purified by sucrose gradient centrifugation and disaggregated by sonication were used as an immunogen for the preparation of this antiserum.

A rabbit antiserum to disaggregated PHF from AD NFT is currently available. This antiserum has been shown to be immunoreactive with disaggregated PHF by ELISA. This antiserum specifically immunostains NFT and degenerating plaque neurites in cases of AD, Down's syndrome and normal aged individuals.  NFT are heterogenous in composition and their composition undergoes changes as the tangle matures. Because monoclonal antibodies are unique to a single epitope, they tend to immunolabel subpopulations of tangles, which contain this epitope. For this reason, a monoclonal antibody that immunolabels intraneuronal tangles, may not immunolabel extracellular tangles. Polyclonal antisera to disaggregated PHF will immunolabel all NFT, both intracellular and extracellular, as well as all PHF-containing neurites. This antiserum works on formalin-fixed, paraffin-embedded sections, formalin-fixed vibratome sections and paraformaldehyde-fixed, frozen sections. It has also been used on western blots and immunolabels the highly insoluble SDS-resistant PHF that are excluded from gel.  This antibody should be a valuable tool for scientists working to understand the role of in AD.

Manufacturing Reference:

Sparkman, D.R., et al., J. Histochem. Cytochem. 38: 703-715, 1990.