passages.id: split_6_test_519_passage
passages.type: progene_text
passages.text: To modify its host range , we have engineered the FPV HA to display four different polypeptides on its N terminus : the epidermal growth factor , an anti - human MHC class I molecules scFv ( single - chain antibody ) , an anti - melanoma antigen scFv , and an IgG Fc - binding polypeptide .