What is claimed is;
1. A conjugate comprising a residue of an IL-7 moiety covalently attached to a water-soluble polymer.
2. The conjugate of claim 1, wherein the IL-7 moiety covalently attached to the water-soluble polymer is covalently attached via a releasable linkage.
3. The conjugate of claim 1, wherein the IL-7 moiety covalently attached to the water-soluble polymer is covalently attached via a stable linkage.
4. The conjugate of any one of claims 1, 2 and 3, wherein the water-soluble polymer is a branched water-soluble polymer.
5. The conjugate of any one of claims 1, 2, 3 and 4, wherein the water-soluble polymer is a polymer selected from the group consisting of poly(alkylene oxide), poly (vinyl pyrrolidone), poly(vinyl alcohol), polyoxazoline, and poly(acryloylmorpholine).
6. The conjugate of claim 5, wherein the water-soluble polymer is a poly(alkylene oxide).
7. The conjugate of claim 6, wherein the poly(alkylene oxide) is a poly(ethylene glycol).
8. The conjugate of claim 7, wherein the poly(ethylene glycol) is terminally capped with an end-capping moiety selected from the group consisting of hydroxy, alkoxy, substituted alkoxy, alkenoxy, substituted alkenoxy, alkynoxy, substituted alkynoxy, aryloxy and substituted aryloxy.
9. The conjugate of any one of claims 1, 2, 3, 4, 5, 6 and 7, wherein the water-soluble polymer has a weight-average molecular weight in a range of from about 500 Daltons to about 100,000 Daltons.

10. The conjugate of any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, wherein the conjugate is covalently attached at an amine group of the residue of the IL-7 moiety.
11. The conjugate of any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, wherein one, two, three or four water-soluble polymers are attached to the residue of the IL-7 moiety.
12. The conjugate of any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, wherein one, two or three water-soluble polymers are attached to the residue of the IL-7 moiety.
13. The conjugate of any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, wherein one or two water-soluble polymers are attached to the residue of the IL-7 moiety.
14. The conjugate of any one of claims 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, wherein one water-soluble polymer is attached to the residue of the IL-7 moiety.
15. The conjugate of any one of the proceedings claims, wherein the IL-7 moiety has an amino acid sequence selected from the group consisting of SEQ ID NO: 1; SEQ ID NO: 2; SEQ ID NO: 3; SEQ ID NO: 4; SEQ ID NO: 5; SEQ ID NO: 6; SEQ ID NO: 7; and SEQ ID NO: 8.
16. A conjugate comprising a residue of an IL-7 moiety covalently attached to a water-soluble polymer, wherein the water-soluble polymer, prior to being covalently attached, is a polymeric reagent bearing an N-hydroxysuccinimidyl group.
17. A pharmaceutical composition comprising a conjugate of any one of claims 1 through 16 and a pharmaceutically acceptable excipient.
18. A method comprising administering to an individual a pharmaceutical composition of claim 17.
19. A method for making a conjugate comprising contacting, under conjugation conditions, an IL-7 moiety with a polymeric reagent.