Monoclonal Antibodies Against Fimbrial Subunits of Colonization Factor Antigen I (CFA/I) Inhibit Binding to Human Enterocytes and Protect Against Enterotoxigenic Escherichia Coli Expressing Heterologous Colonization Factors

Microb Pathog. 1996 Jul;21(1):35-45. doi: 10.1006/mpat.1996.0040.

Abstract

Enterotoxigenic Escherichia coli (ETEC) bind to enterocytes in the small intestine by means of antigenically distinct colonization factors (CFs). By immunizing with isolated subunits of CFA/I fimbriae we have previously produced monoclonal antibodies (MAbs) that cross-react immunologically in vitro with several CFs. Two of these MAbs [S(subunit)-CFA/ I 17:8 and S-CFA/I 5:6] were found to significantly inhibit the binding of ETEC strains expressing either homologous or heterologous CFs, i.e. CFA/I and CS4, to isolated human jejunal enterocytes. The two MAbs also conferred passive protection against fluid accumulation in rabbit ileal loops caused by CFA/I-as well as CS4-expressing ETEC strains. Immunoelectron microscopy studies showed that both MAbs bound specifically to CFA/I as well as to CS4 fimbriae expressed on bacteria. These results indicate the possibility to induce anti-CF antibodies that can protect against ETEC infection caused by bacteria expressing not only homologous but also heterologous CFs, by immunizing with fimbrial subunits.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesins, Bacterial / biosynthesis
  • Adhesins, Bacterial / immunology*
  • Adult
  • Animals
  • Antibodies, Monoclonal / immunology*
  • Bacterial Adhesion / immunology
  • Cross Reactions / immunology
  • Escherichia coli / immunology*
  • Escherichia coli Infections / immunology
  • Escherichia coli Infections / prevention & control*
  • Fimbriae, Bacterial / ultrastructure
  • Humans
  • Ileum / microbiology
  • Immunization, Passive
  • Jejunum / cytology
  • Microscopy, Immunoelectron
  • Rabbits

Substances

  • Adhesins, Bacterial
  • Antibodies, Monoclonal