Indexed on: 25 Jul '06Published on: 25 Jul '06Published in: Archives of Virology
To evaluate the possibility of developing an effective subunit vaccine against Japanese encephalitis virus (JEV), mice were intraperitoneally immunized with either a neutralizing epitope (a 27-amino-acid region of the JEV E protein), or with a fusion protein between this region and a Mycobacterium tuberculosis hsp70. Both antigens were heterologously expressed in Escherichia coli as fusion proteins with thioredoxin. The fusion protein antigen elicited a higher titer of anti-thioredoxin-neutralizing epitope antibodies and a stronger proliferation of lymphocytes than did either the neutralizing epitope (irrespective of the presence of mineral oil as an adjuvant), or the conventional JEV SA14-14-2 vaccine. Assays of antibody isotype and IFN-gamma and IL-4 content in post-immunization serum showed that the fusion protein elicited a higher IgG2a titer and higher levels of IFN-gamma suggesting a potentiation of the Th1 immune response. The fusion protein antigen elicited a long-lived immune response, and the antibodies were able to neutralize JEV in vitro more strongly than did those elicited by the JEV SA14-14-2 vaccine. Immunization with the fusion protein generated both humoral and cellular immune responses to JEV, and the fusion protein appeared to be a more efficient protectant than the JEV SA14-14-2 vaccine.
Indexed on: 06 Apr '19
Published on: 05 Apr '19 in The Canadian journal of infectious diseases & medical microbiology = Journal canadien des maladies infectieuses et de la microbiologie medicale / AMMI Canada