PDGF-D, a new member of the PDGF/VEGF family of growth factors, as well as the nucleotide sequence encoding it, methods for producing it, antibodies and other antagonists to it, transfected and transformed host cells expressing it, pharmaceutical compositions containing it, and uses thereof in medical and diagnostic applications, including methods for stimulating growth of a connective tissue or healing a wound in a mammal, which methods comprise administering to the mammal an effective amount of PDGF-D polypeptides or polynucleotides encoding the PDGF-D polypeptides.