摘要 |
<p>A retroviral vector particle having a modified retroviral envelope polypeptide. The retroviral envelope polypeptide includes the hypervariable polyproline region, or hinge region, and the hypervariable polyproline region, or hinge region is modified to include a heterologous protein or peptide, such as a targeting polypeptide including a binding region which binds to a ligand. Such a retroviral vector may be 'targeted' to various cells for delivery of genetic material to such cells.</p> |