THE MAJOR ENVELOPE GLYCOPROTEIN OF LAV (GP110): IDENTIFICATION, ANTIGENICITY AND NEUTRALIZING CAPACITY OF SPECIFIC ANTIBODIES
Int Conf AIDS. 1985 Apr 14-17;1:24 (abstract no. S6A)
François Clavel, B Krust, D Klatzmann, F Barre-Sinoussi, JC Chermmann and L Montagnier Pasteur Institute and La Pitie-Salpetriere Hospital, Paris.
Using 35S-cystein labelling and SDS-PAGE analysis of LAVI infected cells supernatant lysates, we have characterized a 110K protein, associated with the virus band in zonal centrifugation, and absent in supernatants of uninfected cells. Its glycoprotein nature was assessed by 14C-glucosamine labelling, specific binding to lectins and by treatment with endoglycosidase H. This treatment showed that the protein moiety has a molecular weight close to 90K, in agreement with the sequence data of LAV genome, which indicates that the coding capacity of the env gene is around 95,000. In LAVI infected cells lysates, a precursor of 160K was also identified. Antibodies to gp110 were found in the serum of almost all AIDS
patients, including those lacking antibodies to p25 and p18. Interestingly, the only serum that we found to be able to neutralize LAVI infectivity at 1:10 dilution was from the patient from which LAVI was initially isolated. Other positive sera failed to neutralize LAVI, even at low dilutions. However, the induction of syncitia resulting from the fusion between LAVI infected and uninfected susceptible cells was inhibited by almost all positive sera even by those lacking reactivity with LAV core proteins.
