Immunogenicity and antigenicity of conserved peptides from the envelope of HIV-1 expressed at the surface of recombinant bacteria.
We expressed peptides from the HIV-1 envelope protein at the surface of Escherichia coli by genetic insertions into an exposed loop of the outer membrane protein LamB. Recombinant bacteria expressing eight peptides from gp110 (pep1-pep8), conserved between HIV-1 and HIV-2, were used as live immunogens in rabbits by the intravenous route. The eight constructions elicited anti-LamB antibodies, showing that the hybrid proteins were immunogenic. One of them, LamB-pep8, gave rise to antibodies able to react with gp160 and to neutralize HIV-1 in vitro. We also show that this type of recombinant E. coli can provide a convenient reagent to monitor and characterize specific antibodies. Recombinant clones were used to test sera of seropositive individuals, as well as to narrow down the monoclonal antibody 110-1 recognition site to a cluster of eight residues at the carboxy-terminal end of gp110.
Charbit
A
A
Unité de Programmation Moléculaire et Toxicologie Génétique (CNRS UA271, INSERM U163), Paris, France.
Molla
A
A
Ronco
J
J
Clément
J M
JM
Favier
V
V
Bahraoui
E M
EM
Montagnier
L
L
Leguern
A
A
Hofnung
M
M
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins; D015153:Blotting, Western; D004926:Escherichia coli / Q000235:genetics*; D015686:Gene Products, env / Q000235:genetics / Q000276:immunology; D015488:HIV Antigens / Q000235:genetics / Q000276:immunology*; D019302:HIV Envelope Protein gp160; D015497:HIV-1 / Q000276:immunology*; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D018272:Porins; D011498:Protein Precursors / Q000235:genetics / Q000276:immunology; D011817:Rabbits; D011991:Receptors, Virus / Q000276:immunology; D011995:Recombination, Genetic; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology*
D000911:Antibodies, Monoclonal; D001425:Bacterial Outer Membrane Proteins; D015686:Gene Products, env; D015488:HIV Antigens; D019302:HIV Envelope Protein gp160; D018272:Porins; D011498:Protein Precursors; D011991:Receptors, Virus; D014759:Viral Envelope Proteins; C055004:gp 110 env protein, Human immunodeficiency virus; C016532:maltoporins