%0 Journal Article
%T Serum Antibodies Protect against Intraperitoneal Challenge with Enterotoxigenic Escherichia coli
%A Xinghong Yang
%A Theresa Thornburg
%A Kathryn Holderness
%A Zhiyong Suo
%A Ling Cao
%A Timothy Lim
%A Recep Avci
%A David W. Pascual
%J Journal of Biomedicine and Biotechnology
%D 2011
%I Hindawi Publishing Corporation
%R 10.1155/2011/632396
%X To assess whether anticolonization factor antigen I (CFA/I) fimbriae antibodies (Abs) from enterotoxigenic Escherichia coli (ETEC) can protect against various routes of challenge, BALB/c mice were immunized with a live attenuated Salmonella vaccine vector expressing CFA/I fimbriae. Vaccinated mice elicited elevated systemic IgG and mucosal IgA Abs, unlike mice immunized with the empty Salmonella vector. Mice were challenged with wild-type ETEC by the oral, intranasal (i.n.), and intraperitoneal (i.p.) routes. Naïve mice did not succumb to oral challenge, but did to i.n. challenge, as did immunized mice; however, vaccinated mice were protected against i.p. ETEC challenge. Two intramuscular (i.m.) immunizations with CFA/I fimbriae without adjuvant conferred 100% protection against i.p. ETEC challenge, while a single 30 μg dose conferred 88% protection. Bactericidal assays showed that ETEC is highly sensitive to anti-CFA/I sera. These results suggest that parenteral immunization with purified CFA/I fimbriae can induce protective Abs and may represent an alternative method to elicit protective Abs for passive immunity to ETEC.
%U http://www.hindawi.com/journals/biomed/2011/632396/