Polypeptide growth factor ZVEGF3, methods of making it, polynucleotides encoding it, antibodies that bind to it, and methods of using them are disclosed. The polypeptide comprises an amino acid segment that is at least 90% identical to residues 46-163 of SEQ ID NO:2 or residues 235-345 of SEQ ID NO:2. Multimers of the polypeptide are also disclosed. The polypeptide, multimeric proteins, and polynucleotides can be used in the study and regulation of cell and tissue development, as components of cell culture media, and as diagnostic agents. The antibodies may be used to inhibit cell growth.