A mammalian cytokine-like polypeptide, called Mammalian Cytokine-like polypeptide-10, (Zcyto10), polynucleotides encoding the same, antibodies which specifically bind to the polypeptide, and anti-idiotypic antibodies which bind to the antibodies. Zcyto10 is useful for promoting the healing of wounds and for stimulating the proliferation of platelets.