Comparative immunogenicity of preparations of yeast-derived dengue oral vaccine candidate

• DOI: 10.1186/s12934-018-0876-0
• Publication Date: 2018-02-16T11:10:25Z
• Authors: Jyotiranjan Bal; Nguyen Ngoc Luong; Jisang Park; Ki-Duk Song; Yong-Suk Jang; Dae-Hyuk Kim
• Keywords: Dengue vaccine

Dengue is listed as a neglected tropical disease by the Center for Disease Control and Preservation, there are insufficient integrated surveillance strategies, no effective treatment, limited licensed vaccines. Consisting of four genetically distinct serotypes, dengue virus (DENV) causes serious life-threatening infections due to its complexity. Antibody-dependent enhancement pre-existing cross-reactive well homotypic antibodies further worsens clinical symptoms dengue. Thus, vaccine conferring simultaneous durable immunity each DENV serotypes essential restrict escalation. In deeply affected resource-limited countries, oral vaccination using food-grade organisms considered be beneficial approach in terms costs, patient comfort, simple logistics mass immunization. The current study used mouse model explore immunogenicity an candidate prepared whole recombinant yeast cells (WC) cell-free extracts (CFE) from expressing Escherichia coli heat-labile toxin protein B-subunit (LTB) fused consensus envelope domain III (scEDIII). Mice were treated orally with WC CFE vaccines 2-week intervals 4 weeks changes systemic mucosal immune responses monitored.Both dosage applications LTB-scEDIII stimulated humoral response form dengue-specific serum IgG secretory sIgA. Antigen-specific B cell isolated lymphoid spleen Peyer's patches indicated elevated response. Cellular estimated through lymphocyte proliferation assay higher levels than dosage. Furthermore, sera obtained after both administrations successfully neutralized DENV-1, whereas formulation only DENV-2 serotype, two representative which cause severe infection. Sera mice that fed preparations demonstrated markedly neutralizing titers compared those WC-fed mice. However, feeding elicited strong responses, similar induced intraperitoneal booster purified scEDIII antigen.CFE produced low processing requirements, signifying this fusion shows promise potent against viral