Uses of Mammalian Cytokine; Related Reagents

1 . A method of treating an individual predisposed to develop an IL-23 mediated autoimmune disorder of the metabolic system comprising administering an effective amount of an antagonist of IL-23 or IL-23 Receptor (IL-23R).

2 . The method of claim 1 , wherein the disorder of the metabolic system is diabetes mellitus.

3 . The method of claim 1 , wherein the antagonist specifically binds to a polypeptide or nucleic acid of:

a) IL-23p19; or

b) IL-23R.

4 . The method of claim 1 , wherein the antagonist comprises a:

a) nucleic acid; or

b) small molecule.

5 . The method of claim 4 , wherein the nucleic acid comprises:

a) anti-sense nucleic acid; or

b) small interfering RNA (siRNA).

6 . The method of claim 1 , wherein the antagonist comprises:

a) an antigen binding fragment of an antibody; or

b) a soluble receptor derived from IL-23R.

7 . The method of claim 6 , wherein the antibody is:

a) a polyclonal antibody;

b) a monoclonal antibody;

c) a humanized antibody;

d) an Fab, Fv, or F(ab′) 2 fragment;

e) a single chain antibody;

f) a peptide mimetic of an antibody; or

g) detectably labeled.

8 . The method of claim 1 , wherein the antagonist of IL-23 is co-administered with an:

a) IL-12 antagonist;

b) TNFα antagonist;

c) IL-6 antagonist;

d) IL-17 antagonist; or

e) IL-10 agonist.

9 . The method of claim 1 , wherein the antagonist of IL-23 is co-administered with an immunosuppressive agent.

10 . The method of claim 1 , wherein the immunosuppressive agent is:

a) prednisone;

b) azathioprine; or

c) cyclosporin.

11 . A method of treating an individual exhibiting signs of impaired glucose homeostasis to prevent development of diabetes mellitus, the method comprising administering to the individual an effective amount of an antagonist of IL-23 or IL-23R.

12 . The method of claim 11 , wherein impaired glucose homeostasis is measured by plasma glucose levels either during fasting or after a glucose load.

13 . The method of claim 12 , wherein the plasma glucose levels are:

a) between 110 to 126 mg per dL during fasting; or

b) between 140 and 200 mg per dL after a glucose load.

14 . The method of claim 11 , wherein the antagonist of IL-23 or IL-23R is an antibody or an antigen binding fragment thereof.

15 . The method of claim 14 , wherein the antibody or antigen binding fragment thereof is:

a) a polyclonal antibody;

b) a monoclonal antibody;

c) a humanized antibody;

d) an Fab, Fv, or F(ab′) 2 fragment;

e) a single chain antibody

f) a peptide mimetic of an antibody; or

g) detectably labeled.

16 . The method of claim 15 , wherein the antibody or antigen binding fragment thereof is co-administered with an immunosuppressive agent.

17 . The method of claim 16 , wherein the immunosuppressive agent is:

a) prednisone;

b) azathioprine; or

c) cyclosporin.