Vitronectin:keratinocyte growth factor chimeras
Isolated protein complexes are provided comprising keratinocyte growth factor and vitronectin, or at least domains thereof that enable binding to and activation of both a keratinocyte growth factor receptor and an integrin receptor for vitronectin. These protein complexes include synthetic proteins where the keratinocyte growth factor and vitronectin sequences are joined by a linker sequence. In particular forms, vitronectin sequences do not include a C-terminal heparin binding domain. Also provided are uses of these protein complexes for stimulating or inducing cell migration and/or proliferation in wound healing, tissue engineering, cosmetic and therapeutic treatments such as skin replacement, skin replenishment and treatment of burns where epithelial cell migration is required. In other embodiments, the invention provides inhibition of cancer cell metastasis, particularly in relation to breast cancer.
1. An isolated protein complex in the form of a synthetic chimeric protein, the synthetic chimeric protein comprising:
at least one protein domain of KGF capable of binding a keratinocyte growth factor receptor; and
at least one protein domain of vitronectin (VN) comprising at least one integrin-binding domain;
wherein the synthetic chimeric protein comprises an amino acid sequence comprising at least one of the following:
(i)
(SEQ ID NO: 10)
1-459 VN:(Gly 4 Ser) 4 :1-163 KGF:Gly 4 Ser Gly 4 :6 His,
(ii)
(SEQ ID NO: 11)
1-311 VN:(Gly 4 Ser) 4 :1-163 KGF:Gly 4 Ser Gly 4 :6 His,
(iii)
(SEQ ID NO: 12)
1-125 VN:(Gly 4 Ser) 4 :1-163 KGF:Gly 4 Ser Gly 4 :6 His,
or
(iv)
(SEQ ID NO: 14)
1-64 VN:(Gly 4 Ser) 4 :343-376 VN:(Gly 4 Ser) 4 :1-163
KGF:Gly 4 Ser Gly 4 :6 His.
2. An isolated nucleic acid molecule encoding the isolated protein complex of claim 1 .
3. A genetic construct comprising the isolated nucleic acid molecule of claim 2 operably linked to one or more nucleic acid molecules comprising one or more regulatory nucleotide sequences in a vector.
4. The genetic construct of claim 3 , wherein the genetic construct is an expression construct, and wherein the isolated nucleic acid molecule is operably linked to a heterologous promoter.
5. An isolated host cell comprising the genetic construct of claim 3 .
6. A genetic construct comprising the isolated nucleic acid molecule of claim 2 operably linked to one or more nucleic acid molecules encoding one or more fusion polypeptides.
7. The genetic construct of claim 6 , wherein the one or more fusion polypeptides is one or more of glutathione-S-transferase (GST), Fc portion of human IgG, maltose binding protein (MBP), hexahistidine (HIS 6 ), and c-myc, haemagglutinin and FLAG tags.
8. A pharmaceutical composition comprising the isolated protein complex of claim 1 and a pharmaceutically-acceptable carrier, diluent or excipient.
9. The pharmaceutical composition of claim 8 , wherein the composition comprises a controlled release coating comprising one or more of a hydrophobic polymer, an acrylic resin, a wax, an aliphatic alcohol, a polylactic or polyglycolic acid, and a cellulose derivative.
10. A surgical implant, scaffold or prosthesis comprising the isolated protein complex of claim 1 .
11. The surgical implant, scaffold or prosthesis of claim 10 , wherein the isolated protein complex of claim 1 impregnates or coats the surgical implant, scaffold or prosthesis.
12. A wound or burn dressing comprising the isolated protein complex of claim 1 .
13. A method of treating dermatological wounds in a subject, comprising a step of using the isolated protein complex of claim 1 to bind both a keratinocyte growth factor receptor and an integrin receptor expressed by a cell for inducing, augmenting or promoting at least one of migration and proliferation of said cell thereby treating the dermatological wounds in the subject.
14. The method of claim 13 , wherein the isolated protein complex is administered to the subject to promote cell migration and/or proliferation in situ.
15. The method of claim 14 , wherein the subject is a human.
16. The method of claim 13 , comprising inducing, augmenting or promoting at least one of epithelial cell migration and proliferation as part of therapeutic treatment to facilitate wound healing in situ or to reduce the onset of a dermatologic disorder.
17. The method of claim 16 , wherein the dermatological disorder comprises a hyperproliferative dermatological disorder.
18. The method of claim 13 , comprising administering the isolated protein complex to one or more cells or tissues in vitro.