title: Staphylococcus aureus induces IL-8 expression through its lipoproteins in the human intestinal epithelial cell, Caco-2.
abstract: Staphylococcus aureus can cause the intestinal inflammatory diseases. However, little is known about the molecular mechanism of S. aureus infection in the intestine. In the present study, we investigated whether S. aureus could stimulate human intestinal epithelial cells triggering inflammation. When the human intestinal epithelial cell-line, Caco-2, and the primary colon cells were stimulated with ethanol-inactivated S. aureus, IL-8 expression was induced in a dose-dependent manner. The inactivated S. aureus preferentially stimulated Toll-like receptor (TLR) 2 rather than TLR4. Lipoproteins, lipoteichoic acid (LTA), and peptidoglycan (PGN) are considered as potential TLR2 ligands of S. aureus. Interestingly, S aureus lipoproteins and Pam2CSK4 mimicking Gram-positive bacterial lipoproteins, but not LTA and PGN of S. aureus, significantly induced IL-8 expression in Caco-2 cells. Furthermore, lipoprotein-deficient S. aureus mutant strain failed to induce IL-8 production. Collectively, these results suggest that S. aureus stimulates the human intestinal epithelial cells to induce the chemokine IL-8 production through its lipoproteins, potentially contributing the development of intestinal inflammation.
authors.affiliation: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors.forename: Seok-Seong
authors.initials: SS
authors.lastname: Kang
authors.affiliation: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors.forename: Su Young
authors.initials: SY
authors.lastname: Noh
authors.affiliation: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea.
authors.forename: Ok-Jin
authors.initials: OJ
authors.lastname: Park
authors.affiliation: Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Republic of Korea.
authors.forename: Cheol-Heui
authors.initials: CH
authors.lastname: Yun
authors.affiliation: Department of Oral Microbiology and Immunology, DRI, and BK21 Plus Program, School of Dentistry, Seoul National University, Seoul 110-749, Republic of Korea. Electronic address: shhan-mi@snu.ac.kr.
authors.forename: Seung Hyun
authors.initials: SH
authors.lastname: Han
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry; D018938:Caco-2 Cells; D004305:Dose-Response Relationship, Drug; D004797:Enzyme-Linked Immunosorbent Assay; D004847:Epithelial Cells / Q000276:immunology / Q000382:microbiology; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006801:Humans; D007249:Inflammation / Q000276:immunology; D016209:Interleukin-8 / Q000378:metabolism*; D007422:Intestines / Q000166:cytology / Q000276:immunology / Q000382:microbiology; D008070:Lipopolysaccharides / Q000737:chemistry; D008074:Lipoproteins / Q000737:chemistry*; D010457:Peptidoglycan / Q000737:chemistry; D034741:RNA, Small Interfering / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013211:Staphylococcus aureus / Q000378:metabolism*; D013682:Teichoic Acids / Q000737:chemistry; D051195:Toll-Like Receptor 2 / Q000378:metabolism
chemical_list: D000900:Anti-Bacterial Agents; C508606:CXCL8 protein, human; D016209:Interleukin-8; D008070:Lipopolysaccharides; D008074:Lipoproteins; D010457:Peptidoglycan; D034741:RNA, Small Interfering; C495342:TLR2 protein, human; D013682:Teichoic Acids; D051195:Toll-Like Receptor 2; C009900:lipoteichoic acid
keywords: Inflammation; Interleukin-8; Intestinal epithelial cells; Lipoprotein; Staphylococcus aureus