Monoclonal antibodies targeting microtubule-binding domain of tau protein and methods of detecting tau protein in vivo
Disclosed herein are monoclonal antibodies targeting specific tau epitopes, particularly, microtubule binding domain region 2 or region 4. Also disclosed herein are antibodies or antigen binding fragments thereof that specifically recognize a tau epitope consisting of the amino acid sequence of SEQ ID NO: 9 or 11. Also disclosed herein are methods of detecting tau protein in a subject, comprising performing an assay using the antibodies or antigen binding fragments thereof on the subject or on a biological sample obtained from the subject. Assay kits containing the disclosed antibodies are also provided. Further, methods of treating or preventing a tauopathy in a subject by administering to the subject tau antibodies or antigen-binding fragments thereof are provided.
1. A recombinant antibody comprising a variable heavy (V H ) domain having CDR1, CDR2 and CDR3 sequences and a variable light (V L ) domain having CDR1, CDR2 and CDR3 sequences, wherein the CDR1 sequence of the V H domain comprises the amino acid sequence SEQ ID NO:26; the CDR2 sequence of the V H domain comprises the amino acid sequence SEQ ID NO:27; the CDR3 sequence of the V H domain comprises the amino acid sequence SEQ ID NO:28; the CDR1 sequence of the V L comprises the amino acid sequence SEQ ID NO:23; the CDR2 sequence of the V L domain comprises the amino acid sequence SEQ ID NO:24; and the CDR3 sequence of the V L domain comprises the amino acid sequence SEQ ID NO:25.
2. The antibody of claim 1 , wherein the VL domain comprises the amino acid sequence of SEQ ID NO:21 and the VH domain comprises the amino acid sequence of SEQ ID NO:22.
3. The antibody of claim 1 , wherein the antibody is conjugated to a label.
4. The antibody of claim 3 , wherein the label is selected from an enzyme label, a radioisotope label, a fluorescent label, or a bioluminescent label.
5. The antibody of claim 4 , wherein the enzyme label is horseradish peroxidase, alkaline phosphatase, β-galactosidase, luciferase, acetylcholine esterase, or glucose oxidase.
6. The antibody of claim 4 , wherein the radioisotope label is selected from the group consisting of 125 I, 35 S, 14 C, 32 P and 3 H.
7. The antibody of claim 4 , wherein the fluorescent label is selected from the group consisting of umbelliferone, fluorescein, rhodamine, dichlorotriazinylamine fluorescein, dansyl chloride, fluorescein isothiocyante (FITC), phycoerythrin (PE), Cy5-phycoerythrin (Cy5-PE), Cy7-phycoerythrin (Cy7-PE), allophycocyanin (APC), Cy7-allophycocyanin (Cy7-APC), texas red (TR), and cascade blue.
8. The antibody of claim 4 , wherein the bioluminescent label is selected from the group consisting of photoprotein aequorin, adenosine triphosphate, nicotinamide adenine dinucleotide, and D-luciferin.
9. A kit for an immunoassay, comprising the antibody of claim 1 , and instructional materials for performing the immunoassay.
10. A method of detecting tau protein in a subject, comprising administering to the subject the antibody of claim 3 , and detecting and/or quantifying the antibody or antigen binding fragment thereof bound to tau protein in the subject by positron emission tomography (PET), X-ray computed tomography, single-photon emission computed tomography (SPECT), computed tomography (CT) or computed axial tomography (CAT).