BACKGROUND & AIMS: Norwalk virus (NV) is a major cause of epidemic gastroenteritis. The NV capsid is composed of a single protein that forms recombinant (rNV) virus-like particles (VLPs). In mice, these VLPs are immunogenic when administered orally without adjuvant, and they elicit serum immunoglobulin (Ig) G and intestinal IgA responses. The aim of this study was to evaluate the safety and immunogenicity of rNV VLPs in healthy volunteers. METHODS:Twenty antibody-positive adults were orally administered rNV VLPs in sterile Milli-Q water on days 1 and 21. Vaccine safety and serum rNV-specific total and subclass IgG and IgA antibody responses were monitored. The immune response induced by the VLPs was compared with the response elicited by replicating virus. RESULTS: No side effects were observed or reported by the volunteers. Serum IgG responses to rNV VLPs were dose-dependent, and all vaccinees given 250 microgram of rNV VLPs responded with >/=4-fold increases in serum IgG titers. Most of the volunteers (83%; 15 of 18) responded after the first rNV VLP dose and showed no increase in serum IgG titer after the second dose. CONCLUSIONS: Orally administered rNV VLPs are safe and immunogenic in healthy adults when administered without adjuvant and are useful to test the mucosal delivery of immunogens.
RCT Entities:
BACKGROUND & AIMS:Norwalk virus (NV) is a major cause of epidemic gastroenteritis. The NV capsid is composed of a single protein that forms recombinant (rNV) virus-like particles (VLPs). In mice, these VLPs are immunogenic when administered orally without adjuvant, and they elicit serum immunoglobulin (Ig) G and intestinal IgA responses. The aim of this study was to evaluate the safety and immunogenicity of rNV VLPs in healthy volunteers. METHODS: Twenty antibody-positive adults were orally administered rNV VLPs in sterile Milli-Q water on days 1 and 21. Vaccine safety and serum rNV-specific total and subclass IgG and IgA antibody responses were monitored. The immune response induced by the VLPs was compared with the response elicited by replicating virus. RESULTS: No side effects were observed or reported by the volunteers. Serum IgG responses to rNV VLPs were dose-dependent, and all vaccinees given 250 microgram of rNV VLPs responded with >/=4-fold increases in serum IgG titers. Most of the volunteers (83%; 15 of 18) responded after the first rNV VLP dose and showed no increase in serum IgG titer after the second dose. CONCLUSIONS: Orally administered rNV VLPs are safe and immunogenic in healthy adults when administered without adjuvant and are useful to test the mucosal delivery of immunogens.
Authors: Alan B R Thomson; Laurie Drozdowski; Claudiu Iordache; Ben K A Thomson; Severine Vermeire; M Tom Clandinin; Gary Wild Journal: Dig Dis Sci Date: 2003-08 Impact factor: 3.199
Authors: Samer S El-Kamary; Marcela F Pasetti; Paul M Mendelman; Sharon E Frey; David I Bernstein; John J Treanor; Jennifer Ferreira; Wilbur H Chen; Richard Sublett; Charles Richardson; Robert F Bargatze; Marcelo B Sztein; Carol O Tacket Journal: J Infect Dis Date: 2010-10-27 Impact factor: 5.226
Authors: Patrick R Harrington; Boyd Yount; Robert E Johnston; Nancy Davis; Christine Moe; Ralph S Baric Journal: J Virol Date: 2002-01 Impact factor: 5.103