Characterization of a novel human respiratory syncytial virus chimeric FG glycoprotein expressed using a baculovirus vector

Abstract

Human respiratory syncytial virus (RSV) codes for two glycoproteins (F and G) which have been shown to the major targets for the host antibody response. We have expressed a novel chimeric glycoprotein (FG) in insect cells using a baculovirus vector. The chimeric glycoprotein contains the signal and extracellular regions of the RSV F glycoprotein linked to the extracellular region of the RSV G glycoprotein. Beginning at the amino terminus, the chimeric glycoprotein consists of amino acids 1 to 489 from RSV F followed by amino acids 97 to 279 from RSV G. The chimeric FG glycoprotein did not contain an anchor region and was efficiently secreted into the medium of recombinant baculovirus-infected insect cells. The FG glycoprotein ranged in size from 69K to 91K and was heterogeneous with respect to isoelectric point. The cleavage site present on the F glycoprotein was recognized on the chimeric FG, and the glycoprotein appeared to be antigenically similar to the native RSV F and G glycoproteins.