Immunogenicity of viral B- and T-cell epitopes expressed in recombinant bacterial proteins.
Foreign polypeptides can be expressed as genetic inserts in several permissive sites of MalE and LamB, two Escherichia coli envelope proteins. Several viral B and T-cell epitopes have been inserted in these proteins and we analyzed the role of the molecular environment on the immunogenicity of the foreign epitopes. These studies demonstrated that the antigenicity and immunogenicity of B-cell epitopes depend on their site of insertion in the carrier protein. Using bacteria expressing B-cell epitopes either at the cell surface or in the periplasm, it was also shown that the cellular location of a foreign B-cell epitope expressed by recombinant bacteria determines its T-cell dependent or independent characteristics. Analysis of in vivo immunogenicity of purified LamB or MalE hybrid proteins expressing two different T-cell epitopes established that the immunogenicity of recombinant T-cell epitopes may be strongly affected by both the insertion site and inserted adjacent residues. The in vitro analysis of specific T-cell hybridoma response to hybrid MalE proteins also showed that the molecular context of a T-cell determinant alters the diversity of its T-cell recognition.
Leclerc
C
C
Unité de Biologie des Régulations Immunitaires, Institut Pasteur, Paris, France.
Lo-Man
R
R
Charbit
A
A
Martineau
P
P
Clément
J M
JM
Hofnung
M
M
D018528:ATP-Binding Cassette Transporters; D000595:Amino Acid Sequence; D000941:Antigens / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000276:immunology*; D002352:Carrier Proteins / Q000276:immunology; D000939:Epitopes / Q000276:immunology*; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins; D033902:Periplasmic Binding Proteins; D018272:Porins; D011487:Protein Conformation; D011991:Receptors, Virus / Q000276:immunology; D011993:Recombinant Fusion Proteins / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology*
D018528:ATP-Binding Cassette Transporters; D000941:Antigens; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D000939:Epitopes; D029968:Escherichia coli Proteins; C461619:MalE protein, E coli; D058619:Maltose-Binding Proteins; D009004:Monosaccharide Transport Proteins; D033902:Periplasmic Binding Proteins; D018272:Porins; D011991:Receptors, Virus; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; C016532:maltoporins; C461599:maltose transport system, E coli