Growth factor complex
An isolated protein complex is provided which includes a growth factor, growth factor binding protein and vitronectin. Preferably, the isolated protein complex includes an insulin-like growth factor-I, insulin-like growth factor binding protein-3 or insulin-like growth factor binding protein-5 and vitronectin. Also provided are methods of modulating cell proliferation and/or migration by administering said protein complex for the purposes of wound healing, skin repair and tissue replacement therapy. Conversely, by using agents that disrupt growth factor protein complexes formed in vivo, growth factor-driven cell proliferation and/or migration may be suppressed such as for the purposes of treating cancers, psoriasis, atherosclerosis and wounds prone to hypertrophic scarring.
1. An isolated protein complex consisting of insulin-like growth factor I (IGF-I); an insulin-like growth factor binding protein (IGFBP) selected from the group consisting of: IGFBP-2; IGFBP-3; IGFBP-4 and IGFBP-5; and vitronectin, the insulin-like growth factor binding protein mediating binding between IGF-I and vitronectin.
2. The isolated protein complex of claim 1 , which is produced in recombinant form.
3. The isolated protein complex of claim 1 , wherein vitronectin is multimeric.
4. The isolated protein complex of claim 3 , wherein each vitronectin monomer is bound to the same or different IGFBP selected from the group consisting of: IGFBP2, IGFBP3, IGFBP4 and IGFBP5.
5. The isolated protein complex of claim 1 , wherein vitronectin is monomeric.
6. A pharmaceutical composition comprising the isolated protein complex of claim 1 and a pharmaceutically-acceptable carrier or diluent.
7. A surgical implant or prosthesis comprising the isolated protein complex of claim 1 .
8. An isolated protein complex consisting of IGF-I, IGFBP-3 and multimeric vitronectin, wherein binding of IGF-I and multimeric vitronectin is mediated by IGFBP-3.