Fusion glycoproteins

In an expression vector for infecting or transfecting a cell to express a glycosylated protein, the improvement wherein said protein is a fusion glycoprotein comprising (a) an amino acid sequence that has a biological activity and is from a protein that lacks a hydrophobic glycosylation signal located about seven residues N-terminal to a Cys-Trp-leu-cys sequence (Seq. ID. No. 18), said amino acid sequence being operably linked to the C-terminus of (b) a retrovirus env surface protein,

• N-terminal carrier fragment that includes all of the Cys residues of the N-terminal globular domain of said surface protein, and further wherein said env surface protein contains an N-glycan attachment site within a hydrophobic glycosylation signal located about seven residues N-terminal to a Cys-trp-leu-cys sequence (Seq. ID. No. 18).