|
|
||||||||

* Department of Cancer Immunology and AIDS, Dana Farber Cancer Institute, Boston, MA 02115; and
Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138
Cellular responses to LPS are mediated by a cell surface receptor complex consisting of Toll-like receptor 4 (TLR4), MD-2, and CD14. MD-2 is a secreted protein that interacts with the extracellular portion of TLR4. Site-directed mutagenesis was used to identify the regions of human MD-2 involved in its ability to bind TLR4 and confer LPS responsiveness. A separate region of MD-2 was found to mediate each function. MD-2 binding to TLR4 was dependent on Cys95 and Cys105, which might form an intramolecular disulfide bond. Hydrophilic and charged residues surrounding this area, such as R90, K91, D100, and Y102, also contributed to the formation of the TLR4-MD-2 complex. A different region of MD-2 was found to be responsible for conferring LPS responsiveness. This region is not involved in TLR4 binding and is rich in basic and aromatic residues, several of which cooperate for LPS responsiveness and might represent a LPS binding site. Disruption of the endogenous MD-2-TLR4 complex by expression of mutant MD-2 inhibited LPS responses in primary human endothelial cells. Thus, our data indicate that MD-2 interaction with TLR4 is necessary but not sufficient for cellular response to LPS. Either of the two functional domains of MD-2 can be disrupted to impair LPS responses and therefore represent attractive targets for therapeutic interventions.z
This article has been cited by other articles:
![]() |
B. M. Buchholz, R. S. Chanthaphavong, and A. J. M. Bauer Nonhemopoietic Cell TLR4 Signaling Is Critical in Causing Early Lipopolysaccharide-Induced Ileus J. Immunol., November 15, 2009; 183(10): 6744 - 6753. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. A. J. O'Neill, C. E. Bryant, and S. L. Doyle Therapeutic Targeting of Toll-Like Receptors for Infectious and Inflammatory Diseases and Cancer Pharmacol. Rev., June 1, 2009; 61(2): 177 - 197. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Resman, J. Vasl, A. Oblak, P. Pristovsek, T. L. Gioannini, J. P. Weiss, and R. Jerala Essential Roles of Hydrophobic Residues in Both MD-2 and Toll-like Receptor 4 in Activation by Endotoxin J. Biol. Chem., May 29, 2009; 284(22): 15052 - 15060. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. C. Miller, K. M. Lager, and M. E. Kehrli Jr. Role of Toll-Like Receptors in Activation of Porcine Alveolar Macrophages by Porcine Reproductive and Respiratory Syndrome Virus Clin. Vaccine Immunol., March 1, 2009; 16(3): 360 - 365. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Zimmer, J. Liu, J. L. Clayton, D. S. Stephens, and J. P. Snyder Paclitaxel Binding to Human and Murine MD-2 J. Biol. Chem., October 10, 2008; 283(41): 27916 - 27926. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Keestra and J. P. M. van Putten Unique Properties of the Chicken TLR4/MD-2 Complex: Selective Lipopolysaccharide Activation of the MyD88-Dependent Pathway J. Immunol., September 15, 2008; 181(6): 4354 - 4362. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Teghanemt, R. L. Widstrom, T. L. Gioannini, and J. P. Weiss Isolation of Monomeric and Dimeric Secreted MD-2: ENDOTOXIN{middle dot}sCD14 AND TOLL-LIKE RECEPTOR 4 ECTODOMAIN SELECTIVELY REACT WITH THE MONOMERIC FORM OF SECRETED MD-2 J. Biol. Chem., August 8, 2008; 283(32): 21881 - 21889. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Walsh, M. Gangloff, T. Monie, T. Smyth, B. Wei, T. J. McKinley, D. Maskell, N. Gay, and C. Bryant Elucidation of the MD-2/TLR4 Interface Required for Signaling by Lipid IVa J. Immunol., July 15, 2008; 181(2): 1245 - 1254. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Vasl, P. Prohinar, T. L. Gioannini, J. P. Weiss, and R. Jerala Functional Activity of MD-2 Polymorphic Variant Is Significantly Different in Soluble and TLR4-Bound Forms: Decreased Endotoxin Binding by G56R MD-2 and Its Rescue by TLR4 Ectodomain J. Immunol., May 1, 2008; 180(9): 6107 - 6115. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Tissieres, I. Dunn-Siegrist, M. Schappi, G. Elson, R. Comte, V. Nobre, and J. Pugin Soluble MD-2 is an acute-phase protein and an opsonin for Gram-negative bacteria Blood, February 15, 2008; 111(4): 2122 - 2131. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Neeli, S. N. Khan, and M. Radic Histone Deimination As a Response to Inflammatory Stimuli in Neutrophils J. Immunol., February 1, 2008; 180(3): 1895 - 1902. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Teghanemt, F. Re, P. Prohinar, R. Widstrom, T. L. Gioannini, and J. P. Weiss Novel Roles in Human MD-2 of Phenylalanines 121 and 126 and Tyrosine 131 in Activation of Toll-like Receptor 4 by Endotoxin J. Biol. Chem., January 18, 2008; 283(3): 1257 - 1266. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Teghanemt, P. Prohinar, T. L. Gioannini, and J. P. Weiss Transfer of Monomeric Endotoxin from MD-2 to CD14: CHARACTERIZATION AND FUNCTIONAL CONSEQUENCES J. Biol. Chem., December 14, 2007; 282(50): 36250 - 36256. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Gradisar, M. M. Keber, P. Pristovsek, and R. Jerala MD-2 as the target of curcumin in the inhibition of response to LPS J. Leukoc. Biol., October 1, 2007; 82(4): 968 - 974. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Divanovic, A. Trompette, L. K. Petiniot, J. L. Allen, L. M. Flick, Y. Belkaid, R. Madan, J. J. Haky, and C. L. Karp Regulation of TLR4 signaling and the host interface with pathogens and danger: the role of RP105 J. Leukoc. Biol., August 1, 2007; 82(2): 265 - 271. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M Zimmer, S. M Zughaier, Y.-L. Tzeng, and D. S Stephens Human MD-2 discrimination of meningococcal lipid A structures and activation of TLR4 Glycobiology, August 1, 2007; 17(8): 847 - 856. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. Ohto, K. Fukase, K. Miyake, and Y. Satow Crystal Structures of Human MD-2 and Its Complex with Antiendotoxic Lipid IVa Science, June 15, 2007; 316(5831): 1632 - 1634. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Mitsuzawa, C. Nishitani, N. Hyakushima, T. Shimizu, H. Sano, N. Matsushima, K. Fukase, and Y. Kuroki Recombinant Soluble Forms of Extracellular TLR4 Domain and MD-2 Inhibit Lipopolysaccharide Binding on Cell Surface and Dampen Lipopolysaccharide-Induced Pulmonary Inflammation in Mice J. Immunol., December 1, 2006; 177(11): 8133 - 8139. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Mancek-Keber and R. Jerala Structural similarity between the hydrophobic fluorescent probe and lipid A as a ligand of MD-2 FASEB J, September 1, 2006; 20(11): 1836 - 1842. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Miyake Invited review: Roles for accessory molecules in microbial recognition by Toll-like receptors Innate Immunity, August 1, 2006; 12(4): 195 - 204. [Abstract] [PDF] |
||||
![]() |
M. Kobayashi, S.-i. Saitoh, N. Tanimura, K. Takahashi, K. Kawasaki, M. Nishijima, Y. Fujimoto, K. Fukase, S. Akashi-Takamura, and K. Miyake Regulatory Roles for MD-2 and TLR4 in Ligand-Induced Receptor Clustering J. Immunol., May 15, 2006; 176(10): 6211 - 6218. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Viriyakosol, P. S. Tobias, and T. N. Kirkland Mutational Analysis of Membrane and Soluble Forms of Human MD-2 J. Biol. Chem., April 28, 2006; 281(17): 11955 - 11964. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Cario, D. T. Golenbock, A. Visintin, M. Runzi, G. Gerken, and D. K. Podolsky Trypsin-Sensitive Modulation of Intestinal Epithelial MD-2 as Mechanism of Lipopolysaccharide Tolerance J. Immunol., April 1, 2006; 176(7): 4258 - 4266. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Muroi and K.-i. Tanamoto Structural Regions of MD-2 That Determine the Agonist-Antagonist Activity of Lipid IVa J. Biol. Chem., March 3, 2006; 281(9): 5484 - 5491. [Abstract] [Full Text] [PDF] |
||||
![]() |
S.-H. Lee, K.-K. Kim, I.-C. Rhyu, S. Koh, D.-S. Lee, and B.-K. Choi Phenol/water extract of Treponema socranskii subsp. socranskii as an antagonist of Toll-like receptor 4 signalling Microbiology, February 1, 2006; 152(2): 535 - 546. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Liu, C. C. Cramer, J. Scafidi, and A. E. Davis III N-Linked Glycosylation at Asn3 and the Positively Charged Residues within the Amino-Terminal Domain of the C1 Inhibitor Are Required for Interaction of the C1 Inhibitor with Salmonella enterica Serovar Typhimurium Lipopolysaccharide and Lipid A Infect. Immun., August 1, 2005; 73(8): 4478 - 4487. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Mancek Keber, H. Gradisar, and R. Jerala MD-2 and Der p 2 -- a tale of two cousins or distant relatives? Innate Immunity, June 1, 2005; 11(3): 186 - 192. [Abstract] [PDF] |
||||
![]() |
C. W. Cluff, J. R. Baldridge, A. G. Stover, J. T. Evans, D. A. Johnson, M. J. Lacy, V. G. Clawson, V. M. Yorgensen, C. L. Johnson, M. T. Livesay, et al. Synthetic Toll-Like Receptor 4 Agonists Stimulate Innate Resistance to Infectious Challenge Infect. Immun., May 1, 2005; 73(5): 3044 - 3052. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Hyakushima, H. Mitsuzawa, C. Nishitani, H. Sano, K. Kuronuma, M. Konishi, T. Himi, K. Miyake, and Y. Kuroki Interaction of Soluble Form of Recombinant Extracellular TLR4 Domain with MD-2 Enables Lipopolysaccharide Binding and Attenuates TLR4-Mediated Signaling J. Immunol., December 1, 2004; 173(11): 6949 - 6954. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. D. Bannerman, K. T. Eiting, R. K. Winn, and J. M. Harlan FLICE-Like Inhibitory Protein (FLIP) Protects Against Apoptosis and Suppresses NF-{kappa}B Activation Induced by Bacterial Lipopolysaccharide Am. J. Pathol., October 1, 2004; 165(4): 1423 - 1431. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Gruber, M. Mancek, H. Wagner, C. J. Kirschning, and R. Jerala Structural Model of MD-2 and Functional Role of Its Basic Amino Acid Clusters Involved in Cellular Lipopolysaccharide Recognition J. Biol. Chem., July 2, 2004; 279(27): 28475 - 28482. [Abstract] [Full Text] [PDF] |
||||
![]() |
S.-i. Saitoh, S. Akashi, T. Yamada, N. Tanimura, M. Kobayashi, K. Konno, F. Matsumoto, K. Fukase, S. Kusumoto, Y. Nagai, et al. Lipid A antagonist, lipid IVa, is distinct from lipid A in interaction with Toll-like receptor 4 (TLR4)-MD-2 and ligand-induced TLR4 oligomerization Int. Immunol., July 1, 2004; 16(7): 961 - 969. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Noubir, Z. Hmama, and N. E. Reiner Dual Receptors and Distinct Pathways Mediate Interleukin-1 Receptor-associated Kinase Degradation in Response to Lipopolysaccharide: INVOLVEMENT OF CD14/TLR4, CR3, AND PHOSPHATIDYLINOSITOL 3-KINASE J. Biol. Chem., June 11, 2004; 279(24): 25189 - 25195. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Liu, X. Gu, J. Scafidi, and A. E. Davis III N-Linked Glycosylation Is Required for C1 Inhibitor-Mediated Protection from Endotoxin Shock in Mice Infect. Immun., April 1, 2004; 72(4): 1946 - 1955. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. L. Gioannini, A. Teghanemt, D. Zhang, N. P. Coussens, W. Dockstader, S. Ramaswamy, and J. P. Weiss Isolation of an endotoxin-MD-2 complex that produces Toll-like receptor 4-dependent cell activation at picomolar concentrations PNAS, March 23, 2004; 101(12): 4186 - 4191. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |