Deacylated lipopolysaccharide inhibits neutrophil adherence to endothelium induced by lipopolysaccharide in vitro.

Pohlman, Timothy H.; Munford, Robert S.; Harlan, John M.

doi:10.1084/jem.165.5.1393

Cited by 92 publications

(55 citation statements)

References 27 publications

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“…Taken together, these results imply that crayfish haemocytes are able to react differentially to the polysaccharide and lipid A moieties of LPS, where lipid A is cytotoxic and the polysaccharide portion stimulatory. This result agrees with the recognized endotoxic properties of lipid A in LPS [29,30], and the observed reduction of toxicity of deacylated LPS that still possesses potent inflammatory properties in humans [31,32]. The reaction of live haemocytes to LPS Rc, and LPSdex is similar to the reported effects of these molecules on the proPO activation from cell lysates, where LPS Rc was effective in activating the system and LPSdex was not [12].…”

Section: Discussionsupporting

confidence: 86%

Flow cytometric analysis of crayfish haemocytes activated by lipopolysaccharides

Cárdenas

Dankert

Jenkins

2004

Fish & Shellfish Immunology

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Lipopolysaccharides (LPS) from Gram-negative bacteria are strong stimulators of white river crayfish, Procambarus zonangulus, haemocytes in vitro. Following haemocyte treatment with LPS and with LPS from rough mutant R5 (LPS Rc) from Salmonella minnesota, flow cytometric analysis revealed a conspicuous and reproducible decrease in cell size as compared to control haemocytes. These LPS molecules also caused a reduction in haemocyte viability as assessed by flow cytometry with the fluorescent dyes calcein-AM and ethidium homodimer. The onset of cell size reduction was gradual and occurred prior to cell death. Haemocytes treated with LPS from S. minnesota without the Lipid A moiety (detoxified LPS) decreased in size without a reduction of viability. The action of LPS on crayfish haemocytes appeared to be related to the activation of the prophenoloxidase system because phenoloxidase (PO)-specific activity in the supernatants from control and detoxified LPS-treated cells was significantly lower than that from LPS and LPS-Rc treated cells (P % 0:05). Furthermore, addition of trypsin inhibitor to the LPS treatments caused noticeable delays in cell size and viability changes. These patterns of cellular activation by LPS formulations indicated that crayfish haemocytes react differently to the polysaccharide and lipid A moieties of LPS, where lipid A is cytotoxic and the polysaccharide portion is stimulatory. These effects concur with the general pattern of mammalian cell activation by LPS, thereby indicating common innate immune recognition mechanisms to bacterial antigens between cells from mammals and invertebrates. These definitive molecular approaches used to verify and identify mechanisms of invertebrate haemocyte responses to LPS could be applied with other glycoconjugates, soluble mediators, or xenobiotic compounds.

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Section: Discussionsupporting

confidence: 86%

Flow cytometric analysis of crayfish haemocytes activated by lipopolysaccharides

Cárdenas

Dankert

Jenkins

2004

Fish & Shellfish Immunology

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“…In contrast, endothelial cells are extremely sensitive to endotoxin and respond by expression of endothelial surface markers which define the activated state of enhanced PMN adherence (Pohlman et al, 1987;Wellicome et al, 1990). Since endotoxin constantly bathes intestinal epithelia under physiological conditions, endothelial exposure to endotoxin primarily occurs in association with adjacent bacterial disease, Such differences in endotoxin effects on these systems would, in a teleological sense, seem wholly appropriate.…”

Section: Comparative Evaluation Of Transendothelial and Transepithelimentioning

confidence: 99%

Neutrophil migration across cultured intestinal epithelial monolayers is modulated by epithelial exposure to IFN-gamma in a highly polarized fashion.

Colgan

Parkos

Delp

et al. 1993

The Journal of Cell Biology

158

111

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Abstract. Neutrophil, or polymorphonuclear leukocyte (PMN), migration across intestinal epithelial barriers, such as occurs in many disease states, appears to result in modifications of epithelial barrier and ion transport functions (Nash, S., J. Stafford, and J. L. . Z Clin. Invest. 80:1104-1113; Madara, J. L., C. A. Parkos, S. P. Colgan, R. J. MacLeod, S. Nash, J. B. Matthews, C. Delp, and W. I. Lencer. 1992. J. Clin. Invest. 89:1938-1944). Here we investigate the effects of epithelial exposure to IFN-,), on PMN migration across cultured monolayers of the human intestinal epithelial cell line Tu. Transepithelial migration of PMN was initially assessed in the apicalto-basolateral direction, since previous studies indicate general qualitative similarities between PMN migration in the apical-to-basolateral and in the basolateralto-apical directions. In the apical-to-basolateral direction, epithelial exposure to IFN-.,/rnarkedly upregulated transepithelial migration of PMN in a dose-and timedependent fashion as measured by both electrical and myeloperoxidase assays. This IFN-~/-elicited effect on transmigration was specifically due to a IFN-,/effect on epithelial cells and was not secondary to IFN-,y effects on epithelial tight junction permeability. Moreover, this IFN-.y effect was dependent on epithelial protein synthesis, and involved a pathway in which CDllb/18, but not ICAM-1 or CDlla/18, appeared to play a crucial role in PMN-epithelial adhesion. IFN-~/also substantially modified PMN transepithelial migration in the natural, basolateral-to-apical direction. The IFN-'y effect on naturally directed transmigration was also specifically due to an IFN-3, effect on epithelial cells, showed comparable time and dose dependency to that of oppositely directed migration, was CDllb/18 dependent, and required epithelial protein synthesis. Additionally, however, important qualitative differences existed in how IFN-3, affected transmigration in the two directions. In contrast to apical-to-basolateral directed migration, IFN-,), markedly downregulated transepithelial migration of PMN in the natural direction. This downregulation of PMN migration in the natural direction, however, was not due to failure of PMN to move across filters and into monolayers. Indeed, IFN-3, exposure to epithelia increased the number of PMN which had moved into the basolateral space of the epithelium in naturally directed transmigration. These results represent the first detailed report of influences on PMN transepithelial migration by a cytokine, define conditions under which a qualitative difference in PMN transepithelial migration exists, and suggest that migration of PMN across epithelia in the natural direction may involve multiple steps which can be differentially regulated by cytokines. Specifically, it appears that in naturally directed migration, IFN-~/ may enhance the retention time of the recruited PMN in the paracellular space below tight junctions, and does so, at least in part, by downregulating a PMN-epithelial interactive event req...

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“…For example, treatment of purified LPS with a neutrophil enzyme, acyloxyacyl hydrolase (AOAH), results in the removal of the "piggyback" acyloxyacyl myristate and laurate fatty acids. Such deacylated LPS can no longer stimulate neutrophil adhesion (4). Attempts to analyze the role of lipid A in viable bacterial interactions with cells of the human immune system have been hampered however, by the fact that all lipid A biosynthetic mutants so far identified in E. coli are conditionally lethal (temperature sensitive) (5).…”

Section: Introductionmentioning

confidence: 99%

“…These studies have demonstrated that the lipid A portion of the LPS molecule is responsible for the majority of immunomodulating activity of LPS (3,4). For example, treatment of purified LPS with a neutrophil enzyme, acyloxyacyl hydrolase (AOAH), results in the removal of the "piggyback" acyloxyacyl myristate and laurate fatty acids.…”

Section: Introductionmentioning

confidence: 99%

A novel Escherichia coli lipid A mutant that produces an antiinflammatory lipopolysaccharide.

Somerville¹,

Cassiano²,

Bainbridge³

et al. 1996

J. Clin. Invest.

255

245

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A unique screen was used to identify mutations in Escherichia coli lipid A biosynthesis that result in a decreased ability to stimulate E-selectin expression by human endothelial cells. A mutation was identified in the msb B gene of E. coli that resulted in lipopolysaccharide (LPS) that lacks the myristoyl fatty acid moiety of the lipid A. Unlike all previously reported lipid A mutants, the msb B mutant was not conditionally lethal for growth. Viable cells or purified LPS from an msb B mutant had a 1000-10,000-fold reduction in the ability to stimulate E-selectin production by human endothelial cells and TNF ␣ production by adherent monocytes. The cloned msb B gene was able to functionally complement the msb B mutant, restoring both the LPS to its native composition and the ability of the strain to stimulate immune cells. Nonmyristoylated LPS acted as an antagonist for E-selectin expression when mixed with LPS obtained from the parental strain. These studies demonstrate a significant role for the myristate component of LPS in immune cell activation and antagonism. In addition, the msb B mutant allowed us to directly examine the crucial role that the lipid A structure plays when viable bacteria are presented to host defense cells. ( J. Clin. Invest. 1996. 97:359-365.)

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Deacylated lipopolysaccharide inhibits neutrophil adherence to endothelium induced by lipopolysaccharide in vitro.

Cited by 92 publications

References 27 publications

Flow cytometric analysis of crayfish haemocytes activated by lipopolysaccharides

Flow cytometric analysis of crayfish haemocytes activated by lipopolysaccharides

Neutrophil migration across cultured intestinal epithelial monolayers is modulated by epithelial exposure to IFN-gamma in a highly polarized fashion.

A novel Escherichia coli lipid A mutant that produces an antiinflammatory lipopolysaccharide.

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