Plasmid DNA-based immunization for hepatitis C virus structural proteins: immune responses in mice.
OBJECTIVE
Plasmid DNA-based immunization has been shown to be an effective means of vaccination in animal models. In this study, the immune responses to various hepatitis C virus structural protein antigens were evaluated using this technique.


METHODS
Six recombinant plasmids were constructed. These include, individually, the coding regions for the core protein (pC); E1 (pE1) and E2 (pE2); as well as core, E1, and E2 together (pCE1E2); E1 and E2 together (pE1E2); and finally an E2 construct from which the N-terminal hypervariable region had been deleted (pE2 deltaHVR). These plasmids were transfected into mammalian cells to test their protein expression and were injected into the quadriceps muscles of BALB/c mice to measure specific antibodies and cytotoxic T-lymphocyte responses.


RESULTS
All the recombinant plasmids were shown to express specific antigens transiently in cells and elicited specific antibody responses to core, E1, and E2 in mice. Specific cytotoxic T lymphocyte responses were detected only in mice injected with plasmid constructs encoding the core.


CONCLUSIONS
Genetic immunization can aid the development of hepatitis C virus vaccines by allowing for the rapid construction and evaluation of different expression plasmids as potential immunogens.
Saito
T
T
Laboratory of Hepatitis Viruses, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA.
Sherman
G J
GJ
Kurokohchi
K
K
Guo
Z P
ZP
Donets
M
M
Yu
M Y
MY
Berzofsky
J A
JA
Akatsuka
T
T
Feinstone
S M
SM
D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis; D000917:Antibody Formation; D002460:Cell Line; D004247:DNA / Q000276:immunology*; D005260:Female; D000882:Haplorhini; D016174:Hepacivirus / Q000378:metabolism*; D006801:Humans; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D010957:Plasmids / Q000378:metabolism*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection; D014764:Viral Proteins / Q000276:immunology*
D000914:Antibodies, Viral; D014764:Viral Proteins; D004247:DNA