Binary or polynary targeting and uses thereof
Effector functions are provided to a desired target with improved specificity by use of two or more complementary targeting components. The targeting components assemble a functional moiety at the target. At the target, the functional moiety itself provides an effector function or binds to additional components which provide an effector function. The effector function may be an enzymatic activity, a label or a signal. The binary or polynary targeting system may be used for analyte determination as well.
1. A method to provide a functional paratope to a target, which method comprises:
a) providing two or more complementary targeting components, each of said targeting components comprising a targeting portion and a demitope wherein each said targeting portion binds specifically to one of two or more sites located in close proximity on said target and wherein the binding of the targeting portion to the target brings the demitopes in close proximity wherein said demitopes, when brought into close proximity, assemble into a paratope functional at said target; and
b) contacting said complementary targeting components to an environment comprising said target thereby, inducing assembly of said paratope functional said target.
2. The method of claim 1 , wherein said paratope directly or indirectly binds an effector.
3. The method of claim 1 , wherein the targeting portions are peptides, proteins, oligonucleotides, nucleic acids, vitamins, oligosaccharides, carbohydrates, lipids, haptens, or a complex or combination thereof.
4. The method of claim 3 , wherein the targeting portions are immunoglobulins or fragments thereof.
5. The method of claim 4 , wherein the immunoglobulins or fragments are independently polyclonal antibodies, monoclonal antibodies, Fab fragments, Fab′ fragments, F(ab′) 2 fragments, Fv fragments, diabodies, single-chain antibodies or multi-specific antibodies formed from antibody fragments.
6. The method of claim 1 , wherein the target is a cellular structure.
7. The method of claim 6 , wherein the cellular structure is an intact cell.
8. The method of claim 6 , wherein the cellular structure is a subcellular structure.
9. The method of claim 1 , wherein the targeting portions and the demitopes are covalently linked directly or by a linker.
10. The method of claim 1 , wherein at least one of the targeting components is a fusion protein.
11. The method of claim 2 , wherein the paratope binds to a label.
12. The method of claim 11 , wherein the label generates an immediately detectable signal.
13. The method of claim 2 , wherein the paratope binds to an effector that carries out its effect on the surface of a cell.
14. The method of claim 2 , wherein the effector that binds to the paratope is a peptide, a protein, an oligonucleotide, a nucleic acid, a gene therapy or gene regulatory construct, a virus that carries a gene therapy/regulatory payload, a prodrug, a toxin, a radioactive moiety, a NMR detectable ligand or a fluorescent or phosphorescent ligand.
15. The method of claim 14 , wherein the effector that binds to the paratope is an enzyme.
16. The method of claim 2 , wherein the paratope binds an effector directly.
17. The method of claim 2 , wherein the paratope binds an effector indirectly by a separate linking pair.
18. The method of claim 17 , wherein the separate linking pair comprises:
a) biotin and avidin or streptavidin; or
b) a FLAG epitope and an antibody that binds to said FLAG epitope.
19. The method of claim 1 , which is conducted intracellularly.
20. The method of claim 1 , which is conducted in vivo.
21. The method of claim 1 , wherein the distinct sites located in close proximity on the target are different regions of a single molecule.
22. The method of claim 1 , wherein the distinct sites located in close proximity on the target are located in separate molecules that can attain close proximity by diffusion, either laterally in the plane of a membrane or in three dimensions.
23. A kit to provide an effector to a target, which kit comprises, in one or more containers, two or more complementary targeting components, each of said targeting components comprising a targeting portion that binds specifically to one of two or more distinct sites located in close proximity on a target and a demitope, wherein said demitopes, when brought into close proximity, assemble into a paratope on said target.
24. The kit of claim 23 , which further comprises an effector which interacts with or binds to said assembled paratope.
25. The kit of claim 23 , which further comprises instructions for using the targeting components.