Fibronectin type III domain based scaffold compositions, methods and uses
A protein scaffold based on a consensus sequence of fibronectin type III (FN3) proteins, such as the tenth FN3 repeat from human fibronectin (human Tenascin), including isolated nucleic acids that encode a protein scaffold, vectors, host cells, and methods of making and using thereof have applications in diagnostic and/or therapeutic compositions, methods and devices. In particular, protein scaffold molecules binding to IgG have been identified as useful for diagnostic and/or therapeutic applications.
1. An isolated protein scaffold based on a fibronectin type III (FN3) domain comprising an amino acid sequence derived from a consensus sequence of an FN3 domain, wherein the amino acid sequence has at least 85% identity to SEQ ID NO:16.
2. The isolated protein scaffold of claim 1 , wherein the amino acid sequence has at least 90% identity to SEQ ID NO:16.
3. The isolated protein scaffold of claim 1 , wherein the protein scaffold comprises 7 strands and 6 loops between the strands.
4. The isolated protein scaffold of claim 3 , wherein one or more of the loops is capable of binding to cellular proteins and/or nucleic acid molecules.
5. The isolated protein scaffold of claim 4 , comprising the amino acid sequence of SEQ ID NO:16 and forming loops at or about residues 13-16, 22-28, 38-43, 51-54, 60-64, and 75-81 of SEQ ID NO:16, the loops capable of binding a target comprising cellular proteins and/or nucleic acid molecules.
6. The isolated protein scaffold of claim 5 , wherein one or more of the loops is altered in order to bind to the target.
7. The isolated protein scaffold of claim 5 , wherein said scaffold binds a target with at least one affinity selected from a K D of at least 10 −9 M, at least 10 −10 M, at least 10 −11 M, and at least 10- −12 M, at least 10 −13 M, at least 10 −14 M, and at least 10 −15 M, as determined by surface plasmon resonance or the Kinexa method.
8. A composition comprising the isolated protein scaffold of claim 1 and at least one pharmaceutically acceptable carrier or diluent.
9. A composition according to claim 8 , further comprising at least one compound or polypeptide selected from a detectable label or reporter, a TNF antagonist, an anti-infective drug, a cardiovascular (CV) system drug, a central nervous system (CNS) drug, an autonomic nervous system (ANS) drug, a respiratory tract drug, a gastrointestinal (GI) tract drug, a hormonal drug, a drug for fluid or electrolyte balance, a hematologic drug, an antineoplastic, an immunomodulation drug, an opthalmic, otic or nasal drug, a topical drug, a nutritional drug, a cytokine, and a cytokine antagonist.
10. An article of manufacture for human pharmaceutical or diagnostic use, comprising packaging material and a container comprising a solution or a lyophilized form of the isolated protein scaffold of claim 5 .
11. The article of manufacture of claim 10 , wherein said container is a component of a parenteral, subcutaneous, intramuscular, intravenous, intrarticular, intrabronchial, intraabdominal, intracapsular, intracartilaginous, intracavitary, intracelial, intracerebellar, intracerebroventricular, intracolic, intracervical, intragastric, intrahepatic, intramyocardial, intraosteal, intrapelvic, intrapericardiac, intraperitoneal, intrapleural, intraprostatic, intrapulmonary, intrarectal, intrarenal, intraretinal, intraspinal, intrasynovial, intrathoracic, intrauterine, intravesical, intralesional, bolus, vaginal, rectal, buccal, sublingual, intranasal, or transdermal delivery device or system.