“…During viral maturation, the env gene product of HIV-1 (160K) is glycosylated and further processed to a 120K external envelope glycoprotein (Robey et al, 1985) and a 41K transmembrane glycoprotein (Di Marzo-Veronese et al, 1985). These envelope glycoproteins are involved in virus-cell receptor interactions (McDougal et al, 1986), virus-ceU fusion and syncytium formation (Lifson et al, 1986 ;Sodroski et al, 1986;Kowalski et al, 1987;Stein et al, 1987) and the induction of neutralizing antibodies (Chanh et al, 1986;Dalgleish et al, 1988;Evans et al, 1989).…”