Bacterial translocation is bacterial species dependent: results using the human Caco-2 intestinal cell line

J Trauma. 1994 May;36(5):612-6.


Background: Because of in vivo limitations, the mechanisms underlying the process of bacterial translocation are poorly understood. Thus, an in vitro model system to study the translocation process was developed.

Methods: Transformed human colonic carcinoma (Caco-2) intestinal cells were grown as a polarized monolayer on semi-permeable membranes contained in the upper compartment of a two-compartment system. Once the Caco-2 monolayer had reached confluence, the ability of six different species of bacteria to translocate across the monolayer was tested using a dose-response curve of bacteria (10(2), 10(4), or 10(6)) organisms.

Results: At inocula of 10(4) or 10(6) but not 10(2) organisms, bacteria crossed the monolayer. Bacterial passage across the monolayer was bacterial species specific, with gram-negative enterics being the best, gram-positive aerobes being intermediate translocators, and strict anaerobes being the poorest translocators.

Conclusion: The results of this study indicate that bacteria translocate across the Caco-2 monolayer in a dose-dependent and species-related fashion and support the use of this in vitro epithelial cell culture system as a model for studying bacterial transport.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Bacterial Physiological Phenomena*
  • Colon / cytology
  • Colon / microbiology*
  • Humans
  • Models, Biological
  • Species Specificity
  • Tumor Cells, Cultured