J Vet Sci.  2014 Dec;15(4):575-578. 10.4142/jvs.2014.15.4.575.

Induction of antibody and interferon-gamma production in mice immunized with virus-like particles of swine hepatitis E virus

• Song YJ
• Park WJ
• Lee SK
• Lee JB
• Park SY
• Song CS
• Lee SW
• Seo KH
• Kang YS
• Song JY
• Choi IS

• KMID: 2070246
• DOI: http://doi.org/10.4142/jvs.2014.15.4.575

Abstract

Virus-like particles (VLPs) composed of the truncated capsid protein of swine hepatitis E virus (HEV) were developed and immune responses of mice immunized with the VLPs were evaluated. IgG titers specific for the capsid protein of swine HEV were significantly higher for all groups of mice immunized with the VLPs than those of the negative control mice. Splenocytes from mice immunized with the VLPs also produced significantly greater quantities of interferon (IFN)-gamma than interleukin (IL)-4 and IL-10. These newly developed swine HEV VLPs have the capacity to induce antigen-specific antibody and IFN-gamma production in immunized mice.

Keyword

interferon-gamma; swine hepatitis E virus; virus-like particle

MeSH Terms

Animals
Antibodies, Viral/blood
Capsid Proteins/immunology
Female
Hepatitis E/immunology/*veterinary/virology
Hepatitis E virus/*immunology
Immunization/*veterinary
Interferon-gamma/blood
Mice
Mice, Inbred BALB C
Swine
Swine Diseases/*immunology/virology
Vaccines, Virus-Like Particle/immunology
Viral Hepatitis Vaccines/*immunology
Antibodies, Viral
Capsid Proteins
Interferon-gamma
Vaccines, Virus-Like Particle
Viral Hepatitis Vaccines

Figure

• 

  Fig. 1 Identification of swine hepatitis E virus (HEV) virus-like particles (VLPs) by Western blotting and transmission electron microscopy. (A) VLPs derived from the swine HEV capsid protein were purified on a sucrose gradient and five fractions were collected. Presence of the VLPs was identified by Western blotting with a polyclonal rabbit anti-swine HEV capsid protein antibody. Capsid-specific bands (53 kDa) were produced by samples from all fractions. Lanes 1 and 7 contain a standard protein marker, and lanes 2~5 contain VLPs derived from the capsid protein. (B) Morphology of the HEV VLPs particles viewed with transmission electron microscopy. Scale bar = 100 nm.

• 

  Fig. 2 Antibody titers and cytokine concentration for mice immunized with HEV VLPs. Blood samples were obtained from the mice before immunization and 3 weeks after immunization (0 and 3 weeks as shown in the insert). (A) Antibody titers for the serum samples collected at 3 weeks from mice immunized with 1, 5, or 10 µg of the VLPs were significantly higher (***p < 0.001) than those found for the negative control mice injected with PBS. Splenocytes taken from mice immunized with the VLPs and negative control mice at 3 weeks after immunization were stimulated with the VLPs for 24 h. Cell culture supernatants were then collected and the concentrations of IL-4, IL-10, and IFN-γ were determined. (B) The amount of IL-4 produced by mice immunized with the VLPs was significantly higher (†p < 0.05) than that from the negative control group. (C) The quantity of IL-10 produced by mice immunized with the VLPs was significantly higher (***p < 0.001) than that generated by the negative control group. (D) The concentration of IFN-γ produced by mice immunized with the VLPs was significantly higher (***p < 0.001) than that of the negative control group.

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