Anti IL-34 antibodies

1. An anti-IL-34 antibody or an antigen-binding fragment thereof, said antibody comprising: a light chain comprising CDR-L1 of SEQ ID NO:1, CDR-L2 of SEQ ID NO:2, and CDR-L3 of SEQ ID NO:3; and a heavy chain comprising CDR-H1 of SEQ ID NO:4, CDR-H2 of SEQ ID NO:5, and CDR-H3 of SEQ ID NO:6.

2. The antibody or an antigen-binding fragment thereof of claim 1 , said antibody comprising a light chain comprising SEQ ID NO:7 and a heavy chain comprising SEQ ID NO:8.

3. The antibody or an antigen-binding fragment thereof of claim 1 , said antibody being a monoclonal antibody.

4. The antibody or an antigen-binding fragment thereof of claim 1 , said antibody being a chimeric antibody.

5. The antibody or an antigen-binding fragment thereof of claim 1 , said antibody being a humanized antibody.

6. The antibody or an antigen-binding fragment thereof of claim 1 , wherein said antigen-binding fragment is selected from the list consisting of Fv, scFv, Fab, F(ab′)2, Fab′, scFv-Fc, diabodies, and any antigen-binding fragment whose half-life has been increased by chemical modification with polyalkylene glycol.

7. The antibody or an antigen-binding fragment thereof of claim 1 , wherein said antibody is capable of inhibiting the interaction of IL-34 with at least one of its receptors.

8. The antibody or an antigen-binding fragment thereof of claim 1 , wherein said antibody is capable of inhibiting the interaction of IL-34 with at least one of the receptors selected from the group consisting of Macrophage Colony Stimulating Factor Receptor (M-CSF-R) and Receptor Protein Tyrosine Phosphatase β/ζ (RPTPβ/ζ).

9. The antibody or an antigen-binding fragment thereof of claim 1 , wherein the dissociation constant (KD) of said antibody is KD≤10 −11 M measured by BIAcore.

10. A pharmaceutical composition comprising the antibody or an antigen-binding fragment thereof of claim 1 , and a pharmaceutically-acceptable carrier.

11. A medicament comprising the antibody or an antigen-binding fragment thereof of claim 1 .

12. A kit comprising at least the antibody or an antigen-binding fragment thereof of claim 1 .

13. The kit according to claim 12 , wherein said antibody or antigen-binding fragment thereof is labelled.

14. A method for production of an antibody or an antigen-binding fragment thereof of claim 1 , said method comprising the steps of:

a) growing a host cell comprising a vector expressing:

a.1) a nucleic acid coding for the antibody or an antigen-binding fragment thereof of claim 1 ;

a.2) a nucleic acid comprising the DNA sequences of SEQ ID NO: 9, SEQ ID NO: 10, SEQ ID NO: 11, SEQ ID NO: 12, SEQ ID NO: 13 and SEQ ID NO: 14; or

a.3) a nucleic acid comprising a DNA sequence consisting of a pair of polynucleotides, wherein one of the polynucleotides encodes the light chain and is set forth in SEQ ID NO: 15 and the other polynucleotide encodes the heavy chain and is set forth in SEQ ID NO: 16,

in an appropriate medium, and

b) recovering said antibody.

15. A method for treating a disease dependent on IL-34 selected from the list consisting of an inflammatory disease, auto-immune disease, cancer, and bone disease, comprising administering to a subject in need thereof: an effective amount of the antibody or an antigen-binding fragment thereof of claim 1 , or a pharmaceutical composition comprising the antibody or an antigen-binding fragment thereof of claim 1 and a pharmaceutically-acceptable carrier.

16. The method according to claim 15 , wherein said inflammatory disease dependent on IL-34 is selected from the list consisting of rheumatoid polyarthritis, periodontitis, periprosthetic osteolysis, Gougerot-Sjögren syndrome, arthritis, inflammatory skin pathologies, inflammatory bowel diseases and fibrosis.

17. The method according to claim 15 , wherein said cancer dependent on IL-34 is selected from the list consisting of:

tumour osteolysis,

bone metastases,

brain cancers,

lung cancer, and

bone sarcomas selected from osteosarcoma and Ewing's sarcoma.