Immunogenicity and epitope mapping of a recombinant soluble gp160 of the human immunodeficiency virus type 1 envelope glycoprotein.
The human immunodeficiency virus 1 envelope glycoprotein is synthesized as a precursor, gp160, which is subsequently cleaved to generate the external gp120 and the transmembrane gp41. Both of these cleavage products are known to mediate critical functions of the virus. In order to define the best strategy for the development of a vaccine against human immunodeficiency virus 1, it could be important to map the crucial epitopes on gp160. This entire gp160 is uneasy to purify because it is readily subjected to proteolytic cleavage. Furthermore, it is anchored on the cell membrane and needs detergent treatment for purification. We thus used a recombinant gp160 which was engineered to remove the cleavage sites between gp120 and gp41 and the hydrophobic transmembrane in order to investigate the murine immune response. We selected a panel of 8 monoclonal antibodies which recognize different epitopes on the immunizing recombinant soluble gp160. The reactivity of the monoclonal antibodies was checked on virus-derived gp160, gp120, and gp41. Three antibodies reacted only with gp120 but the others were shown to react with gp41 epitopes or with discontinuous epitopes bridging gp120 and gp41. One subregion of these epitopes was located using a synthetic peptide corresponding to the sequence of gp41. This epitope is apparently part of an immunodominant site since it is recognized by three different monoclonal antibodies. We used competitive inhibition experiments to map the epitopes on recombinant gp160; therefore, the results are probably indicative of the folding of the recombinant soluble gp160 used for immunization.
Laboratoire d'immunopathologie Clinique Médicale A, Hôpital Central, Strasbourg, France.
J L
JL
Pasquali
M P
MP
Kieny
H
H
Kolbe
D
D
Christmann
A M
AM
Knapp
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D006224:Cricetinae; D000939:Epitopes / Q000032:analysis*; D005260:Female; D015686:Gene Products, env / Q000276:immunology*; D015488:HIV Antigens / Q000032:analysis; D019302:HIV Envelope Protein gp160; D015497:HIV-1 / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D010449:Peptide Mapping; D011498:Protein Precursors / Q000276:immunology*; D011994:Recombinant Proteins / Q000276:immunology; D012995:Solubility
D000911:Antibodies, Monoclonal; D000939:Epitopes; D015686:Gene Products, env; D015488:HIV Antigens; D019302:HIV Envelope Protein gp160; D011498:Protein Precursors; D011994:Recombinant Proteins