T. Saito et al., PLASMID DNA-BASED IMMUNIZATION FOR HEPATITIS-C VIRUS STRUCTURAL PROTEINS - IMMUNE-RESPONSES IN MICE, Gastroenterology, 112(4), 1997, pp. 1321-1330
Background & Aims: Plasmid DNA-based immunization has been shown to be
an effective means of vaccination in animal models. In this study, th
e immune responses to various hepatitis C virus structural protein ant
igens weve evaluated using this technique. Methods: Six recombinant pl
asmids were constructed. These include, individually, the coding regio
ns for the core protein (pC); E1 (pE1) and E2 (pE2); as well as cove,
E1, and E2 together (pCE1E2); E1 and E2 together (pE1E2); and finally
an E2 construct from which the N-terminal hypervariable region had bee
n deleted (pE2 Delta HVR). These plasmids were transfected into mammal
ian cells to test their protein expression and were injected into the
quadriceps muscles of BALB/c mice to measure specific antibodies and c
ytotoxic T-lymphocyte responses. Results: All the recombinant plasmids
weve shown to express specific antigens transiently in cells and elic
ited specific antibody responses to core, El, and E2 in mice. Specific
cytotoxic T lymphocyte responses were detected only in mice injected
with plasmid constructs encoding the core. Conclusions: Genetic immuni
zation can aid the development of hepatitis C virus vaccines by allowi
ng for the rapid construction and evaluation of different expression p
lasmids as potential immunogens.