Immune responses of mice to influenza subunit vaccine in combination with CIA07 as an adjuvant.
CIA07 is an immunostimulatory agent composed of E. coli DNA fragments and modified LPS lacking the lipid A moiety. In this study, we investigated whether CIA07 promotes immune responses as an adjuvant to the influenza subunit vaccine. Balb/c mice were immunized intramuscularly once or twice at a 4-week interval with the trivalent influenza subunit vaccine antigen alone or in combination with CIA07 as adjuvant. Antigen-specific serum antibody titers and hemagglutination-inhibition (HI) antibody titers were assessed. At 4 weeks after each immunization, the antigen-specific total serum IgG antibody titer in mice receiving CIA07 was 2 to 3 times higher than that in animals administered antigen alone (P<0.05). The CIA07-treated group additionally displayed higher HI antibody titers against each of the 3 vaccine strains, compared to the antigen group. Animals receiving antigen alone displayed barely detectable antigen-specific serum IgG2a antibody titers. In contrast, coadministration of CIA07 with antigen led to significantly enhanced IgG2a antibody responses, suggesting that CIA07 stimulates a Th1-type immune response. Moreover, the CIA07-treated group displayed a marked increase in the number of interferon gamma-producing CD8(+) T cells in splenocytes. These data collectively demonstrate that CIA07 has the ability to induce both Th1-type cellular and Th2-type humoral immune responses to the influenza subunit vaccine, and support its potential as an effective adjuvant to the influenza vaccine.
Park
Shin Ae
SA
Department of Bioscience & Biotechnology, Institute of Bioscience, Sejong University, Korea.
Song
Eun Sun
ES
Cho
Yang Je
YJ
Ahn
Bo Young
BY
Ha
Suk-Hoon
SH
Seong
Bak Lin
BL
Lee
Kwang Hee
KH
Lee
Na Gyong
NG
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D000914:Antibodies, Viral / Q000032:analysis*; D000917:Antibody Formation; D000956:Antigens, Viral / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D006385:Hemagglutination Inhibition Tests; D007074:Immunoglobulin G / Q000032:analysis; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology; D007252:Influenza Vaccines / Q000737:chemistry / Q000276:immunology / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D018417:Th1 Cells / Q000276:immunology; D014611:Vaccination
D000276:Adjuvants, Immunologic; D000914:Antibodies, Viral; D000956:Antigens, Viral; D007074:Immunoglobulin G; D007252:Influenza Vaccines; D008070:Lipopolysaccharides