Oral immunization with recombinant

• Published in: Future microbiology Vol. 7; no. 8; pp. 1003 - 1010
• Main Authors: Wang, Zhisheng, Gao, Junkai, Yu, Qinghua, Yang, Qian
• Format: Journal Article
• Language: English
• Published: Future Medicine Ltd 01.08.2012
• Subjects: avian influenza; hemagglutinin; mucosal immunity
• ISSN: 1746-0913; 1746-0921
• DOI: 10.2217/fmb.12.69

The aim of the study in this article is to explore a safe, convenient and effective oral mucosal vaccine candidate against highly pathogenic avian influenza. We have constructed an oral mucosal vaccine, LL36EH, by use of the genetically stable -replicating vector pMG36E, which expressed the fusion protein hemagglutinin 1 (HA ) in a live carrier, MG1363. LL36EH was administered orally to mice three times at 2-week intervals. The specific serum IgG and mucosal IgA antibodies were detected and evaluated at different time points after immunization. The results showed that LL36EH could significantly induce specific anti-HA IgA antibody in the intestine and specific anti-HA IgG antibody in the serum (p < 0.05). Additionally, when the splenic lymphocytes isolated from immunized mice were stimulated by HA antigen , splenic lymphocyte proliferative reaction and secretions of the cytokines IFN- and IL-4 were also significantly increased. Most importantly, the mice that were immunized with LL36EH were protected to some extent against lethal challenge of the H5N1 virus. LL36EH triggered the anti-HA -specific humoral and cellular immune responses and protective immunity. Therefore, oral immunization with LL36EH could be a valuable strategy against highly pathogenic avian influenza for humans and animals.