Alzheimer’s disease (AD) is characterized by senile plaques, largely composed of extracellular deposits of Ab peptide, and neurofibrillary tangles (NFT) which are composed of intracellular filamentous aggregates of hyperphosphorylated tau proteins. These tangles represent dense accumulations of distinct paired helical filaments (PHF), in which the major component is a microtubule-associated tau protein. NFTs are biochemically and structurally distinct from the amyloid fibrils in senile plaques. Currently in development are diagnostic antibodies specific to PHF-tau because of the elevated tau levels found in the cerebrospinal fluid of AD patients. Also, the identification of a number of neurodegenerative diseases that are characterized by tau tangles suggests that tangle formation may initiate as well as contribute to the final step in the progressive brain degeneration that characterizes AD. Therefore future AD therapies may be developed to combine targeting amyloid beta deposits with strategies for eliminating tangles. This monoclonal antibody recognizes phosphorylation dependent epitopes of ser-396 on PHF-t as well as fetal tau, but does not recognize autopsy-derived normal adult tau. Phosphoamino ser-396 is one of the two major immunodominant residues of PHF-t. PHF-13 does not recognize unphosphorylated peptide 390-408 or the same peptide phosphorylated at Ser400, Thr403, or Ser404. PHF-13 specifically recognizes the Ser396 phosphorylated peptide and all diphosphorylated peptides containing phosphorylated Ser396.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.