Methods and compositions for the generation and use of conformation-specific antibodies

1. An isolated conformation-specific antibody or antibody fragment thereof, wherein said antibody or antibody fragment comprises:

(a) a heavy chain variable region comprising the heavy chain CDRs of SEQ ID NOs:1-3, and a light chain variable region comprising the light chain CDRs of SEQ ID NOs:4-6; or

(b) a heavy chain variable region comprising the heavy chain CDRs of SEQ ID NOs:7-9, and a light chain variable region comprising the light chain CDRs of SEQ ID NOs:10-12; and

wherein said isolated antibody or antibody fragment thereof binds specifically to the cis conformation of phosphorylated-Threonine231-tau protein (pT231-tau).

2. The isolated antibody or antibody fragment thereof of claim 1 , wherein the antibody or antibody fragment is a single chain antibody.

3. A pharmaceutical composition comprising the antibody or antibody fragment thereof of claim 1 and a pharmaceutically acceptable carrier.

4. A method of treating a tauopathy, traumatic brain injury (TBI), or stroke, said method comprising administering to a subject in need thereof the antibody or antibody fragment of claim 1 , in an amount sufficient to treat said tauopathy, TBI, or stroke.

5. The method of claim 4 , wherein said subject is predisposed to or is at an early stage of said tauopathy.

6. The method of claim 5 , further comprising determining the levels of CSF t-tau, pT181-tau, Aβ42, or ApoE4 in the subject.

7. The method of claim 5 , wherein said subject is predisposed by a history of repeated brain trauma.

8. A method for monitoring a therapeutic response in a subject treated with the antibody or antibody fragment of claim 1 , said method comprising measuring the level of cis pT231-tau or cis:trans pT231-tau ratio in a sample obtained from said subject, wherein a decrease in the level of cis pT231-tau or cis:trans pT231-tau ratio is indicative of an effective therapeutic response to said antibody or antibody fragment.

9. The method of claim 8 , further comprising measuring the levels of one or more of CSF t-tau, pT181-tau, Aβ42, or ApoE4.

10. A method of diagnosing a subject as having a tauopathy or having a predisposition to a tauopathy, said method comprising:

a. measuring the level of cis pT231-tau or cis:trans pT231-tau ratio in a sample obtained from said subject,

b. comparing said level of cis pT231-tau or cis:trans pT231-tau ratio in said sample with a non-diseased reference sample, wherein an elevated level of cis pT231-tau or an increase in cis:trans pT231-tau ratio as compared to said non-diseased reference sample indicates that said subject has or is predisposed to have said tauopathy; and

c. administering to said subject the antibody or antibody fragment of claim 1 in an amount sufficient to treat said tauopathy.

11. An isolated conformation-specific antibody or antibody fragment thereof, wherein said antibody or antibody fragment comprises:

a heavy chain variable region comprising the heavy chain CDRs of SEQ ID NOs:13-15, and a light chain variable region comprising the light chain CDRs of SEQ ID NOs:16-18,

and wherein said isolated antibody or antibody fragment thereof binds specifically to the trans conformation of phosphorylated-Threonine231-tau protein (pT231-tau).

12. The isolated antibody or antibody fragment thereof of claim 11 , wherein the antibody or antibody fragment thereof is a single chain antibody.

13. A pharmaceutical composition comprising the antibody or antibody fragment thereof of claim 11 and a pharmaceutically acceptable carrier.

14. A kit for diagnosing a subject as having a tauopathy or having a predisposition to a tauopathy comprising:

(a) a first isolated conformation-specific antibody or antibody fragment thereof comprising:

(i) a heavy chain variable region comprising the heavy chain CDRs of SEQ ID NOs:1-3, and a light chain variable region comprising the light chain CDRs of SEQ ID NOs:4-6; or

(ii) a heavy chain variable region comprising the heavy chain CDRs of SEQ ID NOs:7-9, and a light chain variable region comprising the light chain CDRs of SEQ ID NOs:10-12,

wherein said first antibody or antibody fragment thereof binds specifically to the cis conformation of pT231-tau,

(b) a second isolated conformation-specific antibody or antibody fragment thereof comprising:

a heavy chain variable region comprising the heavy chain CDRs of SEQ ID NOs:13-15, and a light chain variable region comprising the light chain CDRs of SEQ ID NOs:16-18,

wherein said second antibody or antibody fragment thereof binds specifically to the trans conformation of pT231-tau, and

(c)instructions for the use of the first antibody or antibody fragment thereof and the second antibody or antibody fragment thereof for diagnosing said subject as having a tauopathy or having a predisposition to said tauopathy.