Hybrid cytokine of IL-7 and beta-chain of hepatocyte growth factor

A hybrid cytokine complex comprising:

• a) a cytokine or biologically-active variant thereof;
• b) a growth factor, or biologically-active variant therof;
• and
• c) a flexible linking moiety adjoining a) and b)
• wherein the hybrid cytokine complex is not isolated from a natural source.

A process for producing a hybrid cytokine comprising the β-chain of hepatocyte growth factor (HGF) and rIL7, said method comprising:

• (a) obtaining recombinantly-derived β-chain of hepatocyte growth factor (HGF) by:
• (1) cloning HGFβ cDNA into mammalian or prokoryotic expression vectors and transfecting or transforming the vectors into mammalian or prokoryotic cells;
• (2) growing the transfected or transformed cells in vitro;
• (3) isolating purified β-chain of hepatocyte growth factor (HGF) by extraction from the cell culture;
• and
• (b) obtaining IL-7 from a recombinant or natural source;
• (c) linking the recombinantly-derived β-chain of hepatocyte growth factor (HGF) of step (a) with the IL-7 of step (b) by way of a linker molecule.

A hybrid cytokine complex comprising:

• a) interleukin-7;
• b) the beta chain of HGF;
• c) a flexible linking moiety adjoining a) and b);
• wherein the hybrid cytokine complex is not isolated from a natural source.

A bimolecular protein complex comprising:

• a) a polypeptide which has greater than about 40% sequence identity with interleukin-7;
• b) a polypeptide which has greater than about 40% sequence identity with the beta chain of HGF;
• and
• wherein the bimolecular protein complex supports the proliferation and differentiation of pre-pro-B-cells.

A purified hybrid cytokine complex preparation comprising:

• a) a hybrid cytokine complex comprising interleukin-7 and the beta claim of HGF;
• b) excipient;
• and
• wherein the hybrid cytokine complex preparation is more than about 40% hybrid cytokine complex.