Expression and immunological evaluation of the Escherichia coli-derived hepatitis C virus envelope E1 protein.
Immunological response against envelope protein E1 is very important in natural hepatitis C virus (HCV) infection, although it is insufficient to clear the viraemia. The HCV genomic region encoding the first 149 amino acids of the envelope E1 protein (E1(340), amino acids 192-340) was expressed in Escherichia coli (to a level of 30% of the whole cellular proteins) and purified to 85%. We measured the immune response in rabbits and mice as well as the reactivity against 37 human sera raised against the whole recombinant protein and E1-encoding peptides. From this, 51.1% of human sera were found to react with E1(340). High-level antibodies against E1(340) were obtained in rabbits and mice when immunized. These antibodies had a similar peptide-recognition pattern to that described previously for human sera. The most reactive region was located at the N-terminus of the E1 protein. Cellular immunity in mice was evaluated by delayed-type hypersensitivity assay. It revealed the induction of a CD4+ T-cell-mediated response by this protein. This E1(340) protein and the animal-derived anti-E1 sera are immunological tools that could aid in the monitoring and development of anti-HCV therapies.
Lorenzo
L J
LJ
Departamento de Hepatitis C, División de Vacunas, Centro de Ingeniería Genética y Biotecnología, P.O. Box 6162, La Habana, Cuba.
García
O
O
Acosta-Rivero
N
N
Dueñas-Carrera
S
S
Martínez
G
G
Alvarez-Obregón
J
J
Pichardo
D
D
Ramos
A
A
Guerra
I
I
Morales
J
J
D000595:Amino Acid Sequence; D000818:Animals; D004926:Escherichia coli / Q000235:genetics*; D005260:Female; D006526:Hepatitis C / Q000276:immunology* / Q000821:virology; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000276:immunology; D007106:Immune Sera; D051379:Mice; D008969:Molecular Sequence Data; D011817:Rabbits; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification
C087035:E1 protein, Hepatitis C virus; D007106:Immune Sera; D011994:Recombinant Proteins; D014759:Viral Envelope Proteins