title: Antibody response against plasmid-encoded toxin (Pet) and the protein involved in intestinal colonization (Pic) in children with diarrhea produced by enteroaggregative Escherichia coli.
abstract: Enteroaggregative Escherichia coli (EAEC) is an emerging cause of pediatric and adult travellers diarrhea. The mechanism by which EAEC induce diarrhea is not completely known. Two serine protease autotransporter proteins, named Pet and Pic have been identified in EAEC strains. Pet has enterotoxic and cytotoxic activities, while the role of Pic in pathogenesis may lie on its mucinolytic activity. Little is known about Pet and Pic biological activities in vivo. In this study the antibody responses against these autotransporter proteins in convalescent children is investigated. Fifteen (83%) children showed specific antibodies against Pet or Pic in their sera. IgG and IgM antibodies were the main isotype found. Specific antibodies against Pic, but not against Pet, were detected in sera from age-matched control group. These data show that specific anti-Pet and anti-Pic antibodies are produced during the course of a natural EAEC infection in children.
authors.affiliation: Departamento de Microbiologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, Brazil.
authors.forename: Estela M
authors.initials: EM
authors.lastname: Bellini
authors.forename: Waldir P
authors.initials: WP
authors.lastname: Elias
authors.forename: Tânia A T
authors.initials: TA
authors.lastname: Gomes
authors.forename: Tânia L
authors.initials: TL
authors.lastname: Tanaka
authors.forename: Carla R
authors.initials: CR
authors.lastname: Taddei
authors.forename: Rocio
authors.initials: R
authors.lastname: Huerta
authors.forename: Fernando
authors.initials: F
authors.lastname: Navarro-Garcia
authors.forename: Marina B
authors.initials: MB
authors.lastname: Martinez
mesh_terms: D000375:Aging; D000907:Antibodies, Bacterial / Q000097:blood*; D001427:Bacterial Toxins / Q000276:immunology*; D002675:Child, Preschool; D003967:Diarrhea / Q000276:immunology / Q000382:microbiology*; D004768:Enterotoxins / Q000276:immunology*; D004926:Escherichia coli / Q000276:immunology*; D004927:Escherichia coli Infections / Q000276:immunology*; D029968:Escherichia coli Proteins / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007075:Immunoglobulin M / Q000097:blood; D007223:Infant; D012697:Serine Endopeptidases / Q000276:immunology*
chemical_list: D000907:Antibodies, Bacterial; D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D007074:Immunoglobulin G; D007075:Immunoglobulin M; C027538:heat-labile enterotoxin, E coli; C530786:Pet protein, E coli; D012697:Serine Endopeptidases