Sera from patients with Crohn’s disease break bacterial lipopolysaccharide tolerance of human intestinal epithelial cells via MD-2 activity

Abstract

Myeloid differentiation (MD)-2 is linked to the cell surface as a Toll-like receptor (TLR) 4-bound protein though may also function as a soluble receptor to enable the lipopolysaccharide (LPS)-driven response. We recently demonstrated the importance of MD-2 either as a cell-associated or as a soluble receptor in the control of intestinal epithelial cell response toward LPS. High levels of circulating MD-2 were recently proposed as a risk factor for infectious/ inflammatory diseases as septic shock. We hypothesized that MD-2 might be present in sera from patients with inflammatory bowel disease and have pathogenic consequences. We analysed MD-2 activity in sera from patients with inflammatory bowel disease or from healthy subjects. We measured MD-2 activity as the capacity to mediate LPS-driven stimulation of intestinal epithelial cells (HT29). We found that sera from patients with inflammatory bowel disease, particularly Crohn’s disease, endowed HT29 cells with a markedly higher LPS-dependent stimulating capacity as compared to sera from healthy subjects. The effect of sera was specific for LPS activation and was reduced in the presence of anti-MD-2, and anti-TLR4 antibodies. We conclude that sera from patients with inflammatory bowel disease might contain increased MD-2. This might result in higher local availability of the protein leading to a loss of tolerance toward gut microbiota.

Keywords

inflammatory bowel disease intestinal epithelial cells lipopolysaccharide tolerance MD-2

References

Gioannini TL , Zhang D. , Teghanemt A. , Weiss JP An essential role for albumin in the interaction of endotoxin with lipopolysaccharide-binding protein and sCD14 and resultant cell activation. J Biol Chem 2002; 277: 47818-47825.

Gioannini TL , Teghanemt A. , Zhang D. et al. Isolation of an endotoxin-MD-2 complex that produces Toll-like receptor 4-dependent cell activation at picomolar concentrations. Proc Natl Acad Sci USA 2004 ; 101: 4186-4191.

Visintin A. , Latz E. , Monks BG , Espevik T. , Golenbock DT Lysines 128 and 132 enable lipopolysaccharide binding to MD-2, leading to Toll-like receptor-4 aggregation and signal transduction. J Biol Chem 2003; 278: 48313-48320.

Kennedy MN , Mullen GED , Leifer CA et al. A complex of soluble MD-2 and lipopolysaccharide serves as an activating ligand for Toll-like receptor 4. J Biol Chem 2004; 279: 34698-34704.

Shimazu R. , Akashi S. , Ogata H. , Nagai Y. , Fukudome K. , Miyake K. MD-2, a molecule that confers lipopolysaccharide responsiveness on Toll-like receptor 4. J Exp Med 1999; 189: 1777-1782.

Viriyakosol S. , Mathison JC , Tobias PS , Kirkland TN Structure- function analysis of CD14 as a soluble receptor for lipopolysaccharide. J Biol Chem 2000; 275: 3144-3149.

Viriyakosol S. , Tobias PS , Kitchens RL , Kirkland TN MD-2 binds to bacterial lipopolysaccharide . J Biol Chem 2001; 276: 38044-38051.

Nagai Y. , Akashi S. , Nagafuku M. et al. Essential role of MD-2 in LPS responsiveness and TLR4 distribution . Nat Immunol 2002; 3: 667-672.

Visintin A. , Halmen K. , Latz E. , Monks BG , Golenbock DT Pharmacological inhibition of endotoxin responses is achieved by targeting the TLR4 coreceptor, MD-2. J Immunol 2005; 175: 6465-6472.

10.

Schromm AB , Lien E. , Henneke P. et al. Molecular genetic analysis of an endotoxin nonresponder mutant cell line: a point mutation in a conserved region of MD-2 abolishes endotoxin-induced signaling. J Exp Med 2001; 194: 79-88.

11.

Visintin A. , Mazzoni A. , Spitzer JA , Segal DM Secreted MD-2 is a large polymeric protein that efficiently confers lipopolysaccharide sensitivity to Toll-like receptor 4. Proc Natl Acad Sci USA 2001; 98: 12156-12161.

12.

Lenoir C. , Sapin C. , Broquet AH et al. MD-2 controls bacterial lipopolysaccharide hyporesponsiveness in human intestinal epithelial cells. Life Sci 2008; 82: 519-528.

13.

Pugin J. , Stern-Voeffray S. , Daubeuf B. , Matthay MA , Elson G. , Dunn-Siegrist I. Soluble MD-2 activity in plasma from patients with severe sepsis and septic shock. Blood 2004; 104: 4071-4079.

14.

Cario E. , Golenbock DT , Visintin A. , Runzi M. , Gerken G. , Podolski DK Trypsin-sensitive modulation of intestinal epithelial MD-2 as mechanism of lipopolysaccharide tolerance. J Immunol 2006 ; 176: 4258-4266.

15.

Rembacken BJ , Snelling M. , Hawkey PM , Chalmers DM , Axon AT Non-pathogenic Escherichia coli versus mesalazine for the treatment of ulcerative colitis . Lancet 1999; 354: 635-639.

16.

Schultz M. , Sartor RB Probiotics in inflammatory bowel disease. Gastroenterology 2000; 95: S19-S21.

17.

Teghanemt A. , Widstrom RL , Gioaninni TL , Weiss JP Isolation of monomeric and dimeric secreted (s) MD-2: endotoxin sCD14 and Toll-like receptor 4 ectodomain selectively react with the monomeric from of sMD-2. J Biol Chem 2008; 283: 21881-21889.

18.

Lennard-Jones JE Classification of inflammatory bowel disease . Scand J Gastroenterol Suppl 1989; 170: 2-6.

19.

Cario E. , Podolsky DK Differential alteration in intestinal epithelial cell expression of Toll-like receptor 3 (TLR3) and TLR4 in inflammatory bowel disease. Infect Immun 2000; 68: 7010-7017.

20.

Bantel H. , Schmitz LM , Raible A. , Gregor M. , Schulze-Osthoff K. Critical role of nuclear factor-kB and stress-activated protein kinases in steroid unresponsiveness. FASEB J 2002; 16: 1832-1850.

21.

Komatsu M. , Kobayashi D. , Saito K. et al. Tumor necrosis factor-alpha in serum from patients with inflammatory bowel disease as measured by a highly sensitive immuno-PCR. Clin Chem 2001; 47: 1297-1301.

22.

Jia HP , Kline JN , Penisten A. et al. Endotoxin responsiveness of human airway epithelia is limited by low expression of MD-2. Am J Physiol 2004; 287: L428-L437.

23.

Taireja J. , Dileepan K. , Puri S. et al. Human conjunctival epithelial cells lack lipopolysaccharide responsiveness due to deficient expression of MD-2 but respond after interferon-gamma priming or soluble MD-2 supplementation. Inflammation 2005; 29: 170-181.

24.

Tissieres P. , Dunn-Siegrist I. , Schappi M. et al. Soluble MD-2 is an acute phase protein and an opsonin for Gram-negative bacteria. Blood 2008; 111: 2122-2131.

25.

Sonnenberg A. Seasonal variation of enteric infections and inflammatory bowel disease. Inflamm Bowel Dis 2008; 14: 955-959.

26.

Riley SA , Mani V. , Goodman MJ , Lucas S.

Why do patients with ulcerative colitis relapse?

Gut 1990; 31: 179-183.

27.

Gupta RB , Harpaz N. , Itzkowitz S. et al. Histologic inflammation is a risk factor for progression to colorectal neoplasia in ulcerative colitis: a cohort study. Gastroenterology 2007; 133: 1340-1341.