Isolated microtubule-associated protein tau peptides and kit
A monoclonal antibody which forms an immunological complex with a phosphorylated epitope of an antigen belonging to human abnormally phosphorylated tau proteine. The tau protein can be obtained from a brain homogenate, itself isolated from the cerebral cortex of a patient having Alzheimer's disease.
1. An isolated peptide from 9 to 100 amino acids long, comprising the amino acid sequence YS PG PGT (SEQ ID NO:1) or YSSPG PGT (SEQ ID NO:2), phosphorylated at the positions marked with *, and wherein said peptide is able to form an immunological complex with the monoclonal antibody AT8 produced by the hybridoma deposited at the ECACC on Oct. 8, 1991 under No. 91100806.
2. The isolated peptide of claim 1 , consisting of the amino acid sequence YS PG PGT (SEQ ID NO:1) or YSSPG PGT (SEQ ID NO:2), phosphorylated at the positions marked with *, and wherein said peptide is able to form an immunological complex with the monoclonal antibody AT8 produced by the hybridoma deposited at the ECACC on Oct. 8, 1991 under No. 91100806.
3. A kit comprising the isolated peptide of claim 1 .
4. A kit comprising the isolated peptide of claim 2 .
5. The kit of claim 3 , further comprising instructions for employing the kit for detection, in a sample, of tau protein phosphorylated at Ser(199) and/or Ser(202) and for employing the peptide as a standard or competitor.