Normal enteric bacteria, such as Escherichia coli and Enterococcus faecalis, frequently cause complicating infections in patients with shock and trauma. A common finding in these patients is increased intestinal epithelial permeability, and experiments with cultured enterocytes have shown that bacterial adherence to and internalization by enterocytes is increased following opening of enterocyte tight junctions, exposing the enterocyte lateral surface. Syndecan-1, expressed on the basolateral surface of human enterocytes, is a cell surface transmembrane proteoglycan that expresses heparan sulfate (HS) on its extracellular domain. Our working hypothesis is that HS chains of cell surface proteoglycans, and specifically syndecan-1, may act as an enterocyte receptor or co-receptor for a variety of enteric bacteria. Preliminary data indicated that,like human enterocytes, HS and syndecan-1 are prominently expressed on the basolateral surface of cultured HT-29 enterocytes but not Caco-2 enterocytes. Experiments with HT-29 enterocytes (designed to open enterocyte tight junctions and interfere with bacterial binding to the HS chains on syndecan-1) suggested that HS may be a receptor for gram-positive but not gram-negative bacteria. The HS analog heparin, and HS itself, inhibited adherence and internalization of gram-positive Listeria monocytogenes by HT-29 enterocytes, and experiments with related glycosaminoglycans indicated that this inhibition was specific for HS. Additional preliminary experiments with HT-29 enterocytes indicated that heparin and HS similarly inhibited internalization of gram-positive E. faecalis and Staphylococcus aureus, but not gram-negative Salmonella typhimurium, Proteus mirabilis, and E. coli. Heparin did not have a noticeable effect on internalization of any bacterial species using Caco-2 enterocytes, which express low levels of HS and syndecan-1 Other preliminary experiments indicated that heparin-treated L. monocytogenes was less invasive in orally inoculated mice than was untreated L monocytogenes. In this proposal several experimental tools are used to clarify the interactions of cultured enterocytes with a variety of gram-negative bacteria, while focusing on gram-positive L. monocytogenes, E. faecalis, and S. aureus. These tools include monoclonal antibodies, glycosamino glycans, and heparin disaccharides, and two cell lines transfected to over express syndecan-1, namely ARH-77 myeloma cells and Caco-2 enterocytes. Data from in vitro studies are used to design experiments in mice (outbred and syndecan-1 knockout) to clarify the role of HS and syndecan-1 in intestinal colonization and extra intestinal dissemination of enteric bacteria. Data from these experiments may indicate that enterocytes have a receptor (related to cell surface HS and perhaps syndecan-1) involved in adherence and internalization of a variety of gram-positive bacteria including E. faecalis and S. aureus.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
Project #
Application #
Study Section
Surgery, Anesthesiology and Trauma Study Section (SAT)
Program Officer
Somers, Scott D
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Minnesota Twin Cities
Schools of Medicine
United States
Zip Code
Henry-Stanley, Michelle J; Wells, Carol L (2009) Polyethylene glycol influences microbial interactions with intestinal epithelium. Shock 31:390-6
Hess, Donavon J; Henry-Stanley, Michelle J; Erlandsen, Stanley L et al. (2006) Heparan sulfate proteoglycans mediate Staphylococcus aureus interactions with intestinal epithelium. Med Microbiol Immunol 195:133-41
Henry-Stanley, Michelle; Wells, Carol L (2006) Syndecan-1 as a mediator of bacteria-enterocyte interactions. ScientificWorldJournal 6:466-71
Henry-Stanley, Michelle J; Zhang, Bin; Erlandsen, Stanley L et al. (2006) Synergistic effect of tumor necrosis factor-alpha and interferon-gamma on enterocyte shedding of syndecan-1 and associated decreases in internalization of Listeria monocytogenes and Staphylococcus aureus. Cytokine 34:252-9
Hess, Donavon J; Garni, Robb M; Henry-Stanley, Michelle J et al. (2005) Escherichia coli modulates extraintestinal spread of Staphylococcus aureus. Shock 24:376-81
Erlandsen, Stanley L; Kristich, Christopher J; Dunny, Gary M et al. (2004) High-resolution visualization of the microbial glycocalyx with low-voltage scanning electron microscopy: dependence on cationic dyes. J Histochem Cytochem 52:1427-35
Waters, Christopher M; Hirt, Helmut; McCormick, John K et al. (2004) An amino-terminal domain of Enterococcus faecalis aggregation substance is required for aggregation, bacterial internalization by epithelial cells and binding to lipoteichoic acid. Mol Microbiol 52:1159-71
Wells, Carol L; Hess, Donavon J; Erlandsen, Stanley L (2004) Impact of the indigenous flora in animal models of shock and sepsis. Shock 22:562-8
Waters, Christopher M; Wells, Carol L; Dunny, Gary M (2003) The aggregation domain of aggregation substance, not the RGD motifs, is critical for efficient internalization by HT-29 enterocytes. Infect Immun 71:5682-9