Hepatitis E ; immunology ; prevention & control ; Humans ; Viral Hepatitis Vaccines

Hepatitis E ; etiology ; prevention & control ; Hepatitis E virus ; immunology ; Humans ; Viral Hepatitis Vaccines ; immunology

OBJECTIVETo observe anti-HEV IgG response to vaccination of recombinant antigen fragments and evaluate its protection from Hepatitis E Virus infection in rhesus monkeys (Macaca mulatta).

METHODSTwelve monkeys were divided into three groups and immunized respectively with three different recombinant antigens: namely Ag1 (carboxyl terminal 431 amino acids of ORF2), Ag2 (128aa fragment at the carboxyl terminal of ORF2), and Ag3 (full length ORF3 ligated with two ORF2 fragments encoded by 6743-7126nt and 6287-6404nt). The monkeys were challenged intravenously with fecal suspension from experimentally infected rhesus monkeys, and the other three monkeys served as the placebo group for challenge with HEV. The dynamic changes of the levels of ALT and anti-HEV IgG were examined. Pathological changes of liver tissue were observed by light microscope. Excretion of virus was detected by RT-nPCR.

RESULTSHepatic histopathology of two monkeys in the placebo group was consistent with acute viral hepatitis, and ALT was elevated 3-4 weeks after inoculated with virus, up to 10-20 times higher than normal level. The liver tissue of monkeys immunized with antigen kept normal, ALT in several monkeys elevated mildly, and anti-HEV IgG conversation occurred at 1-2 weeks after vaccination, with the titer reaching 1:12,800. The virus RNA could be detected by RT-nPCR from days 7 to 50 in monkeys of control group, and from days 7 to 21 in vaccinated monkeys after challenged with virus.

CONCLUSIONSThe recombinant antigens could induce the production of anti-HEV IgG, which protected rhesus monkeys from acute Hepatitis symptoms related to HEV infection.

Animals ; Antigens, Viral ; immunology ; Hepatitis E ; prevention & control ; Hepatitis E virus ; immunology ; Immunoglobulin G ; immunology ; Macaca mulatta ; RNA, Viral ; blood ; Recombinant Proteins ; immunology ; Vaccination ; Viral Hepatitis Vaccines ; immunology

Animals ; Hepacivirus ; genetics ; Hepatitis C ; immunology ; prevention & control ; therapy ; virology ; Humans ; Mutation ; Viral Hepatitis Vaccines ; immunology

Animals ; Hepatitis E ; prevention & control ; Hepatitis E virus ; immunology ; Humans ; Viral Hepatitis Vaccines

OBJECTIVETo study the specific cellular immunoresponse of peripheral blood lymphocytes in the chronic hepatitis B patients treated with different doses of recombinant hepatitis B vaccine.

METHODSSeventy-two chronic hepatitis B patients who did not use any anti-HBV drugs within 6 months were randomized into 3 groups (90 micrograms, 60 micrograms, and placebo) in a ratio of 1:1:1. The patients in different groups were treated with different doses of recombinant hepatitis B vaccine in combination with IFN alpha 1b 50 micrograms with 3 times a week for 24 weeks. All patients were followed up for 24 weeks (W24). HBV DNA, HBeAg and liver functions were detected at different time points, and the number of cells that secrete IFN-gamma were detected by ELISPOT.

RESULTSThere were no significant difference in ELISPOT positive ratio among the 3 groups on baseline detection. At W24, 12 cases, 12 cases, and 7 cases showed ELISPOT positive in the group of 90 micrograms, 60 micrograms, and placebo. The proportion of patients who were ELISPOT positive was higher in the groups treated with recombinant hepatitis B vaccine (including the dose of 90 micrograms and 60 micrograms) than that in the placebo group (P=0.0446). HBV DNA turned negative in 6/24 of the patients treated with recombinant hepatitis B vaccine (at both the doses of 90 micrograms and 60 micrograms), and HBeAg/Anti-HBe seroconversion or HBeAg became negative in 7/24 of them. In the placebo group, none of the patients showed undetectable HBV DNA, HBeAg/Anti-HBe seroconversion or HBeAg disappearance. At the 24W of follow up, in the patients who were ELISPOT positive, HBV DNA became undetectable in 4 of the patients treated with recombinant hepatitis B vaccine (at doses of 90 micrograms and 60 micrograms), and HBeAg/Anti-HBe seroconversion or HBeAg disappearance were found in 9 of the cases. In the placebo group, none of the cases showed undetectable HBV DNA, and only 1 case had HBeAg/Anti-HBe seroconversion.

CONCLUSIONThe recombinant hepatitis B vaccine may increase the function of specific T lymphocytes in patients with chronic hepatitis B. There were no significant differences between the patients treated with the dose of 90 micrograms and 60 micrograms hepatitis B vaccine.

Adult ; DNA, Viral ; blood ; Female ; Hepatitis B Vaccines ; immunology ; Hepatitis B, Chronic ; immunology ; Humans ; Interferon-gamma ; biosynthesis ; Male ; Recombinant Proteins ; immunology ; T-Lymphocytes ; immunology ; Vaccines, Synthetic ; immunology

Hepatitis C virus (HCV) core protein is considered to be an attractive candidate for development of protective HCV vaccines. However, this protein may attenuate the induction of systemic immune responses due to its immunomodulatory properties. In this study, we constructed a HCV core gene-containing eukaryotic expression plamid pCI-C, and an in vivo-inducible prokaryotic expression plasmid pZW-C, and transformed the recombinant plasmids into an attenuated Salmonella typhimurium aroA strain SL7207. The resulting bacterial strains SL7207/pCI-C and SL7207/pZW-C were used to orally immunize BALB/c mice, and the immune responses specific to HCV core protein were assessed. Immunization with the recombinant bacteria SL7207/pCI-C led to a persistent drop in percentage of CD3 CD4 T cells, and induced a weak anti-core IgG production. Splenocytes from SL7207/pCI-C immunized mice developed a relatively weak proliferation response and inferior cytotoxic activity compared to those from the mice immunized with bacteria SL7207/pZW-C. Boost immunization with SL7207/ pCI-C yielded limited improvement in immune strength, while the boost with bacteria SL7207/pZW-C significantly enhanced the immune response. These results suggest that de novo synthesis of native HCV core protein may blunt the induction of immune responses. Attenuated S. typhimurium carrying HCV core protein could efficiently activate systemic cellular and humoral responses, and may be a promising strategy for the development of core-based HCV vaccines.
Animals ; Hepacivirus ; genetics ; immunology ; Mice ; Plasmids ; genetics ; Salmonella typhimurium ; genetics ; metabolism ; Vaccines, DNA ; immunology ; Viral Core Proteins ; genetics ; immunology ; Viral Hepatitis Vaccines ; genetics ; immunology

Animals ; Female ; Hepacivirus ; immunology ; Hepatitis C ; prevention & control ; Mice ; Mice, Inbred BALB C ; T-Lymphocytes, Cytotoxic ; immunology ; Vaccination ; Vaccines, DNA ; immunology ; Viral Hepatitis Vaccines ; immunology

China ; Hepatitis B virus ; immunology ; History, 20th Century ; Humans ; Molecular Biology ; history ; Orthomyxoviridae ; immunology ; Viral Vaccines ; immunology ; Virology ; history

In order to study the feasibility of E2 gene fragment of hepatitis virus G(HGV) as a component of DNA vaccine against the hepatitis virus G infection, a 559bp DNA fragment encoding HGV E2 was cloned into plasmid pCMV-S from pThioHis-E2 in the same reading frame with HBsAg gene to form a recombinant plasmid named pCMV-S-E2. BALB/c mice of Kunming strain were immunized with purified plasmid DNA of pCMV-S-E2 by intra-muscularly inoculation. The immunizations were boosted twice at an interval of 14 days. The whole blood was collected from mice orbit on the day-8 after the last boost. Mice sera were screened by ELISA to determine the humoral immune response using E2-GST fusion protein as the immobilized antigen and the sera from mice immunized with pCMV-S as control. The result indicated that the immunization with plasmid DNA of pCMV-S-E2 could induce quite strong humoral immune response.
Animals ; Female ; GB virus C ; immunology ; Hepatitis Antibodies ; blood ; Mice ; Mice, Inbred BALB C ; Plasmids ; Recombinant Fusion Proteins ; biosynthesis ; immunology ; Vaccines, DNA ; immunology ; Viral Envelope Proteins ; genetics ; immunology ; Viral Hepatitis Vaccines ; immunology