1
|
Wild-derived mouse strains, a valuable model to study B cell responses. Mol Immunol 2008; 46:601-12. [PMID: 18951634 DOI: 10.1016/j.molimm.2008.07.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 07/25/2008] [Accepted: 07/26/2008] [Indexed: 12/22/2022]
Abstract
In the present report, we revisited the B cell responsiveness of 7 wild-derived mouse strains to various toll-like receptor ligands (TLR-L). We found that 2 of them, namely PWK and STF presented profound defects in B cell proliferative responses to most of the TLR-L. Yet, their macrophage responses were largely unaffected, suggesting that regulation of TLR pathways are distinct in B cells and macrophages. We also showed that, anti-CD40 mAbs rescued the low proliferative responses to CpG in both PWK and STF B cells. In the other hand, CpG synergized with LPS to induce high levels of proliferation in STF B cells, which did not respond to LPS alone. Cytokine or immunoglobulin (Ig) productions, in vitro, were less impaired than the proliferative responses to LPS or CpG alone. In STF B cells, both ERK, P38 and JNK pathways were affected following in vitro TLR4 or TLR9 signaling. Moreover, while the basal levels of Ig secreting cells and of serum Igs were similar to that of control mice, antibody responses to both TI and TD antigens were severely affected, mainly in STF mice. Our findings therefore highlight the relevance of wild-derived mouse strains and TLR-L to study B cell physiology.
Collapse
|
2
|
Thiriot A, Drapier AM, Vieira P, Fitting C, Cavaillon JM, Cazenave PA, Rueff-Juy D. The Bw cells, a novel B cell population conserved in the whole genus Mus. THE JOURNAL OF IMMUNOLOGY 2007; 179:6568-78. [PMID: 17982046 DOI: 10.4049/jimmunol.179.10.6568] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In common laboratory mouse strains, which are derived from the crossing between three subspecies, peritoneal B cells are enriched in B-1a cells characterized by the CD5(+)Mac-1(+)B220(low)IgM(high)IgD(low)CD43(+)CD9(+) phenotype. Intriguingly in other vertebrates, CD5(+)Mac-1(+) cells have never been found in a specific anatomic site. To ascertain the peculiarity of the CD5(+) peritoneal B cells in laboratory mice, we analyzed the peritoneal B cell subsets in 9 inbred and 39 outbred wild-derived mouse strains belonging to 13 different species/subspecies. We found that most of these strains do not have the CD5(+) B-1a cell population. However, all of these strains including classical laboratory mouse strains, have variable proportions of a novel B cell population: Bw, which is characterized by a unique phenotype (CD5(-)Mac-1(+)B220(high)IgM(high)IgD(high)CD43(-)CD9(-)) and is not restricted to the peritoneal cavity. Bw cells are also distinct from both B-1 and B-2 cells from a functional point of view both by proliferative responses, cytokine secretion and Ab synthesis. Moreover, transfer experiments show that bone marrow and fetal liver cells from wild mice can give rise to Bw cells in alymphoid mice. The conservation of this B cell population, but not of the CD5(+) B-1a, during evolution of the genus Mus, its readiness to respond to TLR ligands and to produce high concentration of autoantibodies suggest that Bw cells play a key role in innate immunity.
Collapse
Affiliation(s)
- Aude Thiriot
- Unité d'Immunophysiopathologie Infectieuse, Institut Pasteur, Department Immunologie, Paris, France
| | | | | | | | | | | | | |
Collapse
|
3
|
Pedron T, Girard R, Chaby R. TLR4-dependent lipopolysaccharide-induced shedding of tumor necrosis factor receptors in mouse bone marrow granulocytes. J Biol Chem 2003; 278:20555-64. [PMID: 12663667 DOI: 10.1074/jbc.m203551200] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We reported previously that bone marrow granulocytes respond to small amounts of enterobacterial lipopolysaccharide (LPS) via a CD14-independent and TLR4-mediated mechanism by de novo expression of an inducible receptor (CD14) and by down-modulation of a constitutive receptor (L-selectin). In this report we address another effect of LPS: the down-regulation of receptors for tumor necrosis factor-alpha. In mouse bone marrow cells (BMC), this down-regulation is detectable soon (20 min) after exposure of the cells to low levels (0.5 ng/ml) of LPS. This temperature-dependent effect is rather selective for LPS and requires the presence of a conventional lipid A structure in the LPS molecule and a functional TLR4 molecule in the cells. The down-modulation, due to a shedding of the receptors, is blocked by p38 MAPK inhibitors, by a furin inhibitor, and by three metalloproteinase inhibitors (BB-3103, TIMP-2, and TIMP-3). In contrast, inhibitors of MEK, protein kinase C, cAMP-dependent protein kinase, and kinases of the Src family do not block the shedding. Analysis of BMC from mice lacking tumor necrosis factor receptor-1 (CD120a-/-) or tumor necrosis factor receptor-2 (CD120b-/-) indicates that the LPS-induced shedding is specific for CD120b. Thus, exposure of BMC to LPS triggers a rapid shedding of CD120b via a protein kinase C- and Src-independent pathway mediated by p38 MAPK, furin, and metalloproteinase. The additive effects of furin and metalloproteinase inhibitors suggest that these enzymes are involved in parallel shedding pathways.
Collapse
MESH Headings
- Animals
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Bone Marrow Cells/metabolism
- Down-Regulation/drug effects
- Enzyme Inhibitors/pharmacology
- Female
- Furin
- Granulocytes/metabolism
- Hematopoiesis/physiology
- Lipopolysaccharides/pharmacology
- Membrane Glycoproteins/metabolism
- Metalloendopeptidases/antagonists & inhibitors
- Metalloendopeptidases/metabolism
- Mice
- Mice, Inbred C3H
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Peptide Fragments/metabolism
- Protease Inhibitors/pharmacology
- Receptors, Cell Surface/metabolism
- Receptors, Tumor Necrosis Factor/genetics
- Receptors, Tumor Necrosis Factor/metabolism
- Receptors, Tumor Necrosis Factor, Type I
- Receptors, Tumor Necrosis Factor, Type II
- Subtilisins/antagonists & inhibitors
- Subtilisins/pharmacology
- Toll-Like Receptor 4
- Toll-Like Receptors
Collapse
Affiliation(s)
- Thierry Pedron
- Unité de Pathogénie Microbienne Moléculaire, Unité INSERM U389, Institut Pasteur, 75015 Paris, France
| | | | | |
Collapse
|
4
|
Pereira JP, Girard R, Chaby R, Cumano A, Vieira P. Monoallelic expression of the murine gene encoding Toll-like receptor 4. Nat Immunol 2003; 4:464-70. [PMID: 12665857 DOI: 10.1038/ni917] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2002] [Accepted: 02/28/2003] [Indexed: 11/08/2022]
Abstract
Defects in the gene encoding Toll-like receptor 4 (Tlr4) result in impaired responses to lipopolysaccharide (LPS), rendering mice sensitive to infections by Gram-negative bacteria. C3H/HeJ mice have a codominant allele with a mutation in Tlr4, which results in an intermediate response to LPS in F1 mice from crosses of responder and C3H/HeJ mice. Here we show that this intermediate response to LPS is due to monoallelic expression of Tlr4. Allele usage is maintained during clonal expansion, a situation that resembles allelic exclusion. In contrast, Tlr4 is deleted on the recessive C57BL/10ScCr allele and all cells from F1 mice from crosses of responder and C57BL/10ScCr mice express TLR4 protein. Thus, Tlr4 is an autosomal gene whose expression is regulated similarly to that of genes on the X chromosome.
Collapse
Affiliation(s)
- João Pedro Pereira
- Unité du Développement des Lymphocytes, CNRS URA 1961, Institut Pasteur, 25 Rue du Docteur Roux, 75015 Paris, France
| | | | | | | | | |
Collapse
|
5
|
Caroff M, Karibian D, Cavaillon JM, Haeffner-Cavaillon N. Structural and functional analyses of bacterial lipopolysaccharides. Microbes Infect 2002; 4:915-26. [PMID: 12106784 DOI: 10.1016/s1286-4579(02)01612-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Bacterial lipopolysaccharides (LPSs) are powerful immunomodulators in infected hosts, and may cause endotoxic shock. Most of them share a common architecture but vary considerably in structural motifs from one genus, species, and strain to another. Cells of the innate immune response recognize evolutionarily conserved LPS molecular patterns of endotoxins and structural details thereby greatly influencing their response.
Collapse
Affiliation(s)
- Martine Caroff
- Equipe Endotoxines, UMR 8619 du Centre National de la Recherche Scientifique, Biochimie, Université de Paris-Sud, Orsay, France.
| | | | | | | |
Collapse
|
6
|
Pedron T, Girard R, Jeyaretnam B, Carlson RW, Chaby R. The lipid A region of lipopolysaccharides from Rhizobiaceae activates bone marrow granulocytes from lipopolysaccharide-hyporesponsive C3H/HeJ and C57BL/10ScCr mice. Immunology 2000; 101:262-70. [PMID: 11012780 PMCID: PMC2327079 DOI: 10.1046/j.1365-2567.2000.00107.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We established in previous studies that the binding of Salmonella lipopolysaccharide (LPS) to constitutive receptors of low affinity triggers the expression of the inducible LPS-binding molecule CD14 in bone marrow cells (BMC) of C3H/HeOU mice, but not in BMC from C3H/HeJ mice. We show in this study that BMC from C3H/HeJ and C57BL/10ScCr mice do not express CD14 after exposure to LPSs from Salmonella enterica and Bordetella pertussis, but do express this marker when treated with several LPSs from Rhizobiaceae, or their lipid A fragments. This shows that the constitutive LPS receptor in BMC from C3H/HeJ and C57BL/10ScCr mice is fully able to trigger a complete signalling cascade. Results of cross-inhibition of the binding of radiolabelled LPS indicated that active LPSs (from R. species Sin-1 and R. galegae) and inactive LPSs (from S. enterica and B. pertussis) bind to the same site of the constitutive LPS receptor of C3H/HeJ cells. Furthermore, binding of R. species Sin-1 LPS, and signalling induced by this LPS, were both inhibited by pre-exposure of C3H/HeJ cells to B. pertussis lipid A. This correlation between binding and signalling suggests that in C3H/HeJ cells, the constitutive receptor, which recognizes a large panel of LPSs from different origins, appears selectively unable to be activated by some particular LPSs, such as those of Enterobacteria and Bordetella.
Collapse
Affiliation(s)
- T Pedron
- Molecular Immunophysiology Unit, URA-1961 of the National Center for Scientific Research, Pasteur Institute, Paris, France
| | | | | | | | | |
Collapse
|
7
|
Souvannavong V, Andréau K, Adam A, Chaby R. Effect of synthetic lipids on apoptosis and expression of alkaline phosphatase in B-lymphocytes: influence on lipopolysaccharide action. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1999; 26:37-47. [PMID: 10518041 DOI: 10.1111/j.1574-695x.1999.tb01370.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Synthetic lipids were examined for their ability to mimic or to antagonize lipopolysaccharide (LPS) action in murine B-lymphocytes. Several recognized effects of LPS were analyzed: prevention of spontaneous apoptosis, expression of alkaline phosphatase (ALP) and stimulation of proliferation. Three synthetic lipids were used for that purpose: a lipopeptide (compound MTPP) which carries non-hydroxylated fatty acids, and is thus unrelated to LPS, and two glycolipids with hydroxylated fatty acids (compounds D2 and PPDm2-B), structurally related to the lipid A region of enterobacterial and Rhodopseudomonas LPS, respectively. We found that the ability of these lipids to induce LPS-like responses was not correlated with their structural analogy with LPS. Thus, the lipopeptide, MTPP, mimicked LPS in the three activities, whereas the glycolipid, D2, did not. In contrast, the ability of synthetic lipids to block LPS effects was correlated with their structural analogy with LPS. We thus observed that compound D2 selectively blocked LPS-induced ALP expression and that PPDm2-B selectively inhibited LPS-induced prevention of apoptosis. These synthetic lipids could therefore be useful for studying the LPS-mediated signals involved in B-cell activation and apoptosis.
Collapse
Affiliation(s)
- V Souvannavong
- Endotoxin Group, UMR 8619, CNRS, University of Paris-Sud, Bât. 430, 91405, Orsay, Cedex, France.
| | | | | | | |
Collapse
|
8
|
Brackett DJ, Lerner MR, Lacquement MA, He R, Pereira HA. A synthetic lipopolysaccharide-binding peptide based on the neutrophil-derived protein CAP37 prevents endotoxin-induced responses in conscious rats. Infect Immun 1997; 65:2803-11. [PMID: 9199453 PMCID: PMC175395 DOI: 10.1128/iai.65.7.2803-2811.1997] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The lipid A component of lipopolysaccharide (LPS) derived from Escherichia coli has been implicated as a significant mediator in the development of circulatory and metabolic dysfunction and lethality associated with sepsis. A synthetic peptide corresponding to amino acid residues 20 through 44 of the neutrophil-derived 37-kDa cationic antimicrobial protein (CAP37 P(20-44)) possesses lipid A binding characteristics which may be useful in attenuating in vivo responses induced during circumstances of endotoxemia, including sepsis. The E. coli LPS to be used in the in vivo study was shown to be attenuated by CAP37 P(20-44) in a dose-dependent manner in the in vitro reaction with Limulus amoebocyte lysate. Intravenous infusion of CAP37 P(20-44) (1.5 or 3.0 mg/kg of body weight) with E. coli LPS (250 microg/kg over 30 min) into conscious, unrestrained rats prevented LPS-induced hyperdynamic and hypodynamic circulatory shock, hyperlactacidemia, and leukopenia in a dose-related fashion. CAP37 P(20-44) (0.2, 1.0, and 5.0 mg/kg) administered intravenously to conscious, actinomycin D-sensitized rats following a lethal dose of LPS neutralized LPS toxicity, resulting in dose-dependent 7-day survival rates of 30, 50, and 80%, respectively. CAP37 P(20-44) (5.0 mg/kg) significantly inhibited the endotoxin-induced increase in circulating tumor necrosis factor alpha in sensitized rats. These data demonstrate that CAP37 P(20-44) has the capacity to abolish in vivo biological responses to LPS that are relevant to human sepsis and to significantly neutralize the toxicity of circulating E. coli LPS.
Collapse
Affiliation(s)
- D J Brackett
- Department of Surgery, University of Oklahoma Health Sciences Center, and Department of Veterans Affairs Medical Center, Oklahoma City 73190, USA
| | | | | | | | | |
Collapse
|
9
|
Holst O, Ulmer AJ, Brade H, Flad HD, Rietschel ET. Biochemistry and cell biology of bacterial endotoxins. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1996; 16:83-104. [PMID: 8988390 DOI: 10.1111/j.1574-695x.1996.tb00126.x] [Citation(s) in RCA: 123] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- O Holst
- Research Center Borstel, Center for Medicine and Biosciences, Germany
| | | | | | | | | |
Collapse
|
10
|
Fahmi H, Charon D, Mondange M, Chaby R. Endotoxin-induced desensitization of mouse macrophages is mediated in part by nitric oxide production. Infect Immun 1995; 63:1863-9. [PMID: 7729896 PMCID: PMC173236 DOI: 10.1128/iai.63.5.1863-1869.1995] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Refractoriness (tolerance) to endotoxin effects, such as induction of tumor necrosis factor alpha (TNF-alpha) secretion, can be elicited in vitro in macrophages by preexposure of cells to endotoxin (lipopolysaccharide [LPS]) itself. The aim of this study was to determine whether this phenomenon is due to negative feedback mediated by the free radical nitric oxide (NO) produced by cells when they are activated by LPS. Among several efficient inhibitors of NO production, NG-monomethyl-L-arginine did not induce concomitant inhibition of TNF-alpha secretion. Mouse macrophages that were exposed to LPS in the presence of NG-monomethyl-L-arginine partially maintained the ability to secrete TNF-alpha in response to a second LPS stimulation, compared with cells preexposed to LPS alone, thus suggesting that NO is involved in part in LPS-induced desensitization of cells. Furthermore, direct exposure of cells to the NO-generating compounds sodium nitroprusside and S-nitroso-N-acetylpenicillamine mimicked LPS-induced desensitization. However, low concentrations of a synthetic lipid (lipid M4) that is structurally analogous to the reducing end of the lipid A moiety of LPS induced desensitization of mouse macrophages without concomitant production of NO. Taken together, these data suggest that although NO actually takes part in LPS-induced desensitization of mouse macrophages, additional and yet unknown mechanisms must also exist.
Collapse
Affiliation(s)
- H Fahmi
- Laboratory of Immunology, Faculty of Science, Université Sidi Mohamed Ben Abdellah, Fès, Morocco
| | | | | | | |
Collapse
|
11
|
Hmama Z, Mey A, Normier G, Binz H, Revillard JP. CD14 and CD11b mediate serum-independent binding to human monocytes of an acylpolygalactoside isolated from Klebsiella pneumoniae. Infect Immun 1994; 62:1520-7. [PMID: 7513300 PMCID: PMC186345 DOI: 10.1128/iai.62.5.1520-1527.1994] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A water-soluble acylpolygalactosyl (APG) of 34 kDa was obtained from the Klebsiella pneumoniae membrane by alkaline hydrolysis and delipidation. APG comprises a poly(1,3)galactose chain, a core, and a lipid moiety made of a glucosamine disaccharide with two N-linked beta OH-myristates. The monocyte binding sites for APG were investigated by flow cytometry. Biotin-labelled APG (Biot-APG) bound to monocytes at 4 degrees C in the absence of serum, calcium, and magnesium. The binding was dose dependent, saturable, and displaced by unlabelled APG. Neither the polysaccharide chain present in APG-related molecules nor the PPi group or additional ester-linked myristates and palmitates were required for APG binding. The role of CD11b and CD14 was demonstrated by competitive inhibition with monoclonal antibodies and by the uptake of APG by these solubilized proteins. APG was rapidly internalized into monocytes at 37 degrees C while CD14 and CD11b/CD18 molecules were partially down-modulated. Lipopolysaccharides (LPS) from the same K. pneumoniae strain and from Escherichia coli and Salmonella minnesota partially competed for Biot-APG binding in the absence but not in the presence of serum. When altered by alkaline hydrolysis, those LPS became strong competitors for APG binding. It was concluded that alkaline hydrolysis of the K. pneumoniae membrane yielded molecules structurally related to LPS which bind to LPS membrane receptors in the absence of serum.
Collapse
Affiliation(s)
- Z Hmama
- Laboratoire d'Immunologie, Institut Nationale de la Santé et de la Recherche Médicale U80, Université Claude Bernard Lyon, Hôpital E. Herriot, France
| | | | | | | | | |
Collapse
|
12
|
Pedron T, Girard R, Turco S, Chaby R. Phosphatidylinositol-anchored molecules and inducible lipopolysaccharide binding sites of human and mouse bone marrow cells. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)41963-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
|
13
|
Burd RS, Battafarano RJ, Cody CS, Farber MS, Ratz CA, Dunn DL. Anti-endotoxin monoclonal antibodies inhibit secretion of tumor necrosis factor-alpha by two distinct mechanisms. Ann Surg 1993; 218:250-9; discussion 259-61. [PMID: 8373268 PMCID: PMC1242957 DOI: 10.1097/00000658-199309000-00004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE To determine whether monoclonal antibodies (mAbs) directed against lipopolysaccharide (LPS, endotoxin) act by promoting LPS neutralization, LPS uptake by macrophages, or both processes, the authors assessed the effects of these agents on LPS-induced cytokine secretion and cellular uptake of LPS. SUMMARY BACKGROUND DATA MAbs directed against LPS have been shown to attenuate LPS-induced macrophage tumor necrosis factor-alpha (TNF-alpha) secretion, a process that may contribute to protective capacity. The mechanisms by which this process occurs have not been established. METHODS MAbs directed against LPS were evaluated in vitro for their capacity to (1) inhibit TNF-alpha secretion, and (2) alter fluorescein isothiocyanate-labeled LPS uptake (employing flow cytometry analysis and fluorescence microscopy) by the macrophage-like cell line RAW 264.7. RESULTS MAb 8G9, an IgG3 directed against the O-antigen polysaccharide region of Escherichia coli 0111:B4 LPS, significantly reduced LPS-induced TNF-alpha secretion and promoted a more than 40-fold increase in LPS uptake by macrophages. The authors established that this was mediated by a Fc receptor-mediated process because 8G9 F(ab')2 fragments that lack the Fc portion of the IgG molecule were capable of inhibiting TNF-alpha secretion, but did not promote increased LPS uptake to the same degree. Cross-reactive, anti-deep core/lipid A mAb 1B6, an IgG2a, also promoted uptake of E. coli 0111:B4 LPS and O-antigen polysaccharide-deficient E. coli J5 LPS, but only inhibited TNF-alpha secretion induced by E. coli J5 LPS to which it binds most efficiently. MAb 3D10, an IgM also directed against the O-antigen polysaccharide region of E. coli 0111:B4 LPS, inhibited TNF-alpha secretion but did not increase cellular uptake of LPS, presumably acting solely due to LPS neutralization. Polymyxin B, an antibiotic that binds stoichiometrically to the lipid A portion of LPS, inhibited TNF-alpha secretion and prevented cellular LPS uptake. CONCLUSIONS These results suggest that IgG and IgM anti-LPS mAbs exert protective capacity by extracellular neutralization of LPS, while IgG Fc receptor-mediated cellular uptake also may serve to bypass macrophage activation and TNF-alpha secretion by promoting internalization and intracellular neutralization.
Collapse
Affiliation(s)
- R S Burd
- Department of Surgery, University of Minnesota, Minneapolis
| | | | | | | | | | | |
Collapse
|
14
|
Girard R, Pedron T, Kosma P, Chaby R. A synthetic analog of the 3-deoxy-D-manno-2-octulosonic acid disaccharide moiety of rough-type endotoxins does not bind to mouse peritoneal macrophages and human monocytes. Infect Immun 1993; 61:3616-24. [PMID: 7689537 PMCID: PMC281056 DOI: 10.1128/iai.61.9.3616-3624.1993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Strong evidence supports the concept that lipid A is the main biologically active region of endotoxins and is recognized by specific binding sites of different cell types. However, receptors for carbohydrates are also present on mononuclear phagocytes, and it has been suggested that one of these lectin-like proteins may be specific for the 3-deoxy-D-manno-2-octolosonic acid (Kdo) residues of endotoxins. To reexamine this hypothesis, we prepared a 125I-labeled conjugate consisting of a synthetic Kdo-2,4-Kdo disaccharide covalently linked to bovine serum albumin (125I-Kdo2-BSA). The Kdo disaccharide residues of this radiolabeled conjugate were fully accessible to a monoclonal antibody which reacts specifically with this epitope. However, 125I-Kdo2-BSA did not exhibit any detectable specific binding on thioglycolate-elicited mouse peritoneal macrophages or on human monocytes. Furthermore, the specific binding of biotin-labeled lipopolysaccharide derivatives to mouse macrophages and human monocytes was not inhibited by a soluble synthetic Kdo-2,4-Kdo-polyacrylamide copolymer or by a synthetic glycolipid consisting of an alpha-Kdo residue glycosidically linked to O-6 of allyl-4-O-phosphoryl-N-3-hydroxytetradecanoyl-beta-D-glucosaminide. These results indicate that binding sites specific for Kdo are not present (or not accessible) on the surface of mouse macrophages and human monocytes.
Collapse
Affiliation(s)
- R Girard
- Unité d'Immunophysiologie Moléculaire, URA-145 du Centre National de la Recherche Scientifique, Institut Pasteur, Paris, France
| | | | | | | |
Collapse
|
15
|
Lasfargues A, Caroff M, Chaby R. Structural features involved in the mitogenic activity of Bordetella pertussis lipopolysaccharides for spleen cells of C3H/HeJ mice. FEMS IMMUNOLOGY AND MEDICAL MICROBIOLOGY 1993; 7:119-29. [PMID: 8401423 DOI: 10.1111/j.1574-695x.1993.tb00390.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Spleen cells from the C3H/HeJ mouse strain cannot be stimulated by many smooth-type lipopolysaccharides (LPSs), and by the main biologically-active region (lipid A) of these molecules. The genetic origin of this defect (expression of the mutant allele Lpsd at the chromosome 4 locus) was established over 20 years ago, but its biochemical nature has remained undefined. Several investigators have noted, however, that some particular LPSs can bypass this defect, and stimulate the proliferation of C3H/HeJ B lymphocytes. In this study we compare the mitogenic activities of the LPSs isolated from a wild strain (1414) and from a mutant 'rough' strain (A100) of Bordetella pertussis. Both LPS-1414 and LPS-A100 were mitogenic for C3H/HeJ spleen cells, but their lipid A fragments were not. This indicates that a carbohydrate structure proximal to lipid A is involved in the mitogenic activity. However, the isolated polysaccharides were not mitogenic. Four sugars are common to both LPS-1414 and LPS-A100: an heptose, and three sugars bearing free amino groups. After removal of these four sugars from the LPSs by nitrous acid treatment, the recovered lipooligosaccharides were not mitogenic in Lpsd spleen cells. The results suggest that substructures present in lipid A and in this group of four sugars are both required for induction of a mitogenic effect in Lpsd splenocytes, whereas lipid A alone can stimulate Lpsn spleen cells.
Collapse
Affiliation(s)
- A Lasfargues
- Equipe Edotoxines, URA-1116 du Centre National de la Recherche Scientifique, Université de Paris-Sud, Orsay, France
| | | | | |
Collapse
|
16
|
Pedron T, Girard R, Kosma P, Chaby R. Preparation and binding specificity of a monoclonal antibody recognizing 3-deoxy-D-manno-2-octulosonic acid (Kdo) in lipopolysaccharides of Re chemotype. Hybridoma (Larchmt) 1992; 11:765-77. [PMID: 1294455 DOI: 10.1089/hyb.1992.11.765] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A mouse monoclonal antibody (MAb E1) was raised against the lipopolysaccharide (LPS) of the Re mutant R595 of Salmonella minnesota. This IgG3 antibody (MAb E1), unstable at low pH and low ionic strength, was purified by chromatography on QAE Sepharose A50. The binding specificity of MAb E1 was characterized by direct and inhibition enzyme immunoassays, using natural LPSs from different strains and chemotypes, and synthetic analogs of LPS substructure of the 3-deoxy-D-manno-2-octulosonic acid (Kdo) and Lipid A regions. Among various LPSs, MAb E1 reacted exclusively with those of Re-chemotype. It recognized alpha-Kdo- monosaccharide and disaccharide structures present as non-reducing side chains in various Re-type LPSs and synthetic antigens. The antibody did not react with Lipid A or various lipids, and the presence of the lipid region was not necessary for the reaction. The recognition of the epitope was not reduced by the presence of a substituent at O-8 of one of the two Kdo units present in the Re LPS from Proteus mirabilis, but the reaction was inhibited by phosphorylation of O-4 of Kdo, by the proximity of core (heptose) or Lipid A (acylated glucosamine) residues, or by certain LPS-LPS interactions.
Collapse
Affiliation(s)
- T Pedron
- Unité d'Immunophysiologie Moléculaire, URA-145 du C.N.R.S., Institut Pasteur, Paris, France
| | | | | | | |
Collapse
|
17
|
Tobias PS, Mathison J, Mintz D, Lee JD, Kravchenko V, Kato K, Pugin J, Ulevitch RJ. Participation of lipopolysaccharide-binding protein in lipopolysaccharide-dependent macrophage activation. Am J Respir Cell Mol Biol 1992; 7:239-45. [PMID: 1381594 DOI: 10.1165/ajrcmb/7.3.239] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Only recently has the mechanism for lipopolysaccharide (LPS) recognition by macrophages been elucidated. In contrast to many ligand receptor interactions, the interaction of LPS with its receptor, CD14, on myeloid cells is greatly enhanced by prior complexation of LPS with LPS-binding protein (LBP), a recently discovered plasma glycoprotein. LBP is found in normal serum or plasma in the 5 to 10 micrograms/ml range. In plasma, it reacts rapidly but transiently with LPS. LPS-LBP complexes then react with CD14 bearing cells. Blocking CD14 with monoclonal antibodies or removal of LBP from plasma blocks the ability of the cells to react with LPS-LBP complexes and also blocks release of cytokines and other mediators from the cells. In the normal lung, bronchoalveolar lavage fluid contains low levels of LBP. However, during acute lung injury, LBP levels may rise by transudation and enhance activation of alveolar macrophages to release injurious mediators. Description of this pathway for LPS recognition by macrophages and other leukocytes offers the possibility of developing new reagents to block LPS recognition and prevent the development of endotoxemia.
Collapse
Affiliation(s)
- P S Tobias
- Department of Immunology, Scripps Research Institute, La Jolla, CA 92037
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Wang MH, Flad HD, Feist W, Brade H, Kusumoto S, Rietschel ET, Ulmer AJ. Inhibition of endotoxin-induced interleukin-6 production by synthetic lipid A partial structures in human peripheral blood mononuclear cells. Infect Immun 1991; 59:4655-64. [PMID: 1937825 PMCID: PMC259092 DOI: 10.1128/iai.59.12.4655-4664.1991] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The effect of two synthetic lipid A partial structures, compound 406 (or LA-14-PP, identical in structure to the lipid A precursor, known as Ia or IVa) and compound 401 (lipid X), on the in vitro modulation of endotoxin (lipopolysaccharide)-induced interleukin-6 production by human blood mononuclear cells was investigated. Lipopolysaccharide of Salmonella abortus equi and synthetic Escherichia coli-type lipid A (compound 506, or LA-15-PP) had potent interleukin-6-inducing capacities. The maximum release of interleukin-6 was found after stimulation with 1 to 10 ng of lipopolysaccharide or 10 to 100 ng of synthetic E. coli-type lipid A per ml. Both synthetic lipid A partial structures (compounds 406 and 401) failed to induce interleukin-6 release. However, they inhibited lipopolysaccharide- or lipid A-induced interleukin-6 production in a dose-dependent manner. Inhibition was found not only in mononuclear cells but also in purified monocytes and was not due to a shift in the kinetics of cytokine production. Suppression was manifested in the early stage of interleukin-6 production. Inhibition was also found in the presence of recombinant gamma interferon, indicating that compound 406 and recombinant gamma interferon act in different, independent pathways. Our data, therefore, indicate that the inhibition of interleukin-6 production by lipid A partial structures may help elucidate the mechanism of interaction of the lipid A component of lipopolysaccharide with immune cells in the inflammatory reaction during gram-negative infection.
Collapse
Affiliation(s)
- M H Wang
- Department of Immunology and Cell Biology, Borstel, Germany
| | | | | | | | | | | | | |
Collapse
|
19
|
Tahri-Jouti MA, Chaby R. Binding of endotoxin to macrophages: distinct effects of serum constituents. Immunol Invest 1991; 20:377-86. [PMID: 1937584 DOI: 10.3109/08820139109057763] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The respective roles of serum lipoproteins, and of the complement component C3, in the binding of endotoxin (LPS) to macrophages were analyzed by an in vitro assay using [3H]LPS. The addition of an anti-C3 serum in the medium induced an apparent abolishment of the specific binding of LPS to mouse macrophages, but this effect appeared to be due to an actual increase of nonspecific binding. Isolated complexes of LPS with lipoproteins of high density (HDL3) and of very high density (VHDL) did not bind to macrophages. Furthermore, addition of HDL3 and VHDL in the incubation medium inhibited the specific binding of LPS to macrophages. These results suggest that C3 reduces nonspecific interactions between LPS and macrophages whereas associations between LPS and HDL3 or VHDL inhibit specific LPS-macrophage interactions.
Collapse
|
20
|
Tahri-Jouti MA, Chaby R. Specific binding of lipopolysaccharides to mouse macrophages--I. Characteristics of the interaction and inefficiency of the polysaccharide region. Mol Immunol 1990; 27:751-61. [PMID: 2402244 DOI: 10.1016/0161-5890(90)90084-d] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Tritium-labeled lipopolysaccharide interacted specifically and reversibly with mouse peritoneal macrophages. The binding was higher at 22 degrees C than at 4 degrees C, but was no longer observable at 37 degrees C. The specificity of the interaction (inhibition with unlabeled LPS) was strictly dependent on the presence of serum, and required divalent cations. The binding was saturable. The specific binding sites of peritoneal macrophages were saturated with 6-9 x 10(6) LPS molecules/cell, and those of macrophage-like cell lines with 2-3 x 10(6) molecules/cell. The binding of LPS was not inhibited by ligands of scavenger receptors (maleylated BSA) or complement receptors (zymosan), but was strongly inhibited with dexamethasone, a glucocorticoid which is known to modulate the expression of other surface markers of macrophages. The polysaccharide region of the LPS, as well as 3-deoxy-2-octulosonic acid (KDO) coupled to bovine serum albumin, did not bind to macrophages, whereas a specific binding was observed with a lipid A-BSA conjugate.
Collapse
Affiliation(s)
- M A Tahri-Jouti
- 1116 du Centre National de la Recherche Scientifique, Université de Paris-Sud, Orsay, France
| | | |
Collapse
|