Immunogenicity and efficacy of oral or intranasal Shigella flexneri 2a and Shigella sonnei proteosome-lipopolysaccharide vaccines in animal models

Abstract

Immunity against shigellosis has been shown to correlate with the presence of antibodies specific for Shigella lipopolysaccharide (LPS). We here propose a new candidate vaccine for shigellosis composed of purified Shigella flexneri 2a or Shigella sonnei LPS hydrophobically complexed with group C type 2b Neisseria meningitidis outer membrane protein proteosomes. Immunization of mice either orally or intranasally with this complex induced specific homologous anti-LPS antibodies in both intestinal and respiratory secretions as well as in sera. Strong anamnestic responses were found after two or three immunizations. LPS alone, alkaline-detoxified LPS, or alkaline-detoxified LPS complexed with proteosomes was not effective. Oral or intranasal immunization of guinea pigs with two or more doses of this proteosome-LPS vaccine elicited homologous protection against Shigella keratoconjunctivitis (Serény test). These data demonstrate that proteosomes can be used as an effective mucosal vaccine delivery system and that orally or intranasally administered acellular vaccines can protect against Shigella infections.

Intranasal Immunization with Yersinia enterocolitica O:8 Cellular Extract Protects against Local Challenge Infection

“…Intranasal immunization. On days 0 and 7, groups of fifteen mice were given 100 µg of CE or veronal buffer (control) in 20 111 volumes (29). Two micrograms of cholera toxin (CT) (from Vibrio cholerae type Inaba 5898, Calbiochem 227035) were added to the first dose.…”

Outer membrane vesicles for vaccination and targeted drug delivery

“…The studies showed that OMVs could not only be combined with proteins but also with other components. The study showed that meningitides-derived OMVs can be complexed with Shigella-specific LPS to provide the immunity against Shigella keratoconjuctivitis (Orr, Robin, Cohen, Arnon, & Lowell, 1993). Another study showed that when combined with inactivated respiratory syncytial virus (iRVS), N. meningitidis OMVs enhanced the protective immunity (Etchart et al, 2006).…”

A bivalent vaccine confers immunogenicity and protection against Shigella flexneri and enterotoxigenic Escherichia coli infections in mice

“…Six weeks prior to infection, mice received CVD 1208S-122 or the vector intranasally (10 6 CFU/ mouse in 10 µL of saline) in three weekly doses. We used intranasal route due to vast evidence in the literature indicating its effective immunogenicity for shigellosis and other enteric infections 20,21 . In order to allow development of antibody production, we performed challenge infections 4 weeks after the last immunization.…”