Composition containing a chimeric neuregulin polypeptides and method of making such polypeptides are disclosed. The chimeric neuregulin comprises a first moiety of at least 10 amino acids, wherein the first moiety is derived from a first polypeptide； and a second moiety of at least 5 amino acids, wherein the second moiety is derived from a second polypeptide； wherein the first polypeptide is a neuregulin and the chimeric neuregulin exhibits an enhanced binding affinity to integrin, Erb 3, or Erb 4 comparing to that of the first neuregulin.
