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I M Goldstein

Publications and source records attributed to I M Goldstein.

At least 37 records · Page 2Linked to original sources
PubMed1986

Chemotactic peptides modulate adherence of human polymorphonuclear leukocytes to monolayers of cultured endothelial cells.

We have used a new centrifugation assay to examine the effects of highly purified human C5a and C5a des Arg, as well as effects of N-formyl-methionyl-leucyl-phenylalanine (FMLP), on both the extent and strength of human polymorphonuclear leukocyte (PMN) adherence to monolayers of cultured human umbilical vein endothelial cells. At concentrations that were chemotactic for PMN, C5a (0.1 nM), C5a des Arg (5.0 nM), and FMLP (1.0 nM) significantly reduced the percentage of PMN that adhered to endothelial monolayers. Adherence also was reduced by C5a des Arg that was generated by incubating (37 degrees C, 30 min) fresh human serum with either zymosan or purified C5a. High concentrations of C5a (greater than 1.0 nM) and FMLP (greater than 50 nM) that diminished PMN chemotaxis significantly enhanced the percentage of PMN that adhered tightly to endothelial cells (adherent cells resisted a dislodgment force of 1200 X G). Tight adherence of PMN to endothelial cells also was increased by high concentrations of C5a that were added to human serum in which carboxypeptidase N activity was destroyed by heating (56 degrees C, 30 min), and by C5a that was generated by incubating (37 degrees C, 30 min) fresh human serum with zymosan in the presence of the carboxypeptidase N inhibitor, epsilon-aminocaproic acid. High concentrations of C5a des Arg (up to 80 nM) neither enhanced adherence of PMN to endothelial cells nor decreased PMN migration. Thus, a reciprocal relation exists between PMN migration and PMN adherence to endothelial cells in response to chemotactic factors. At concentrations that are chemotactic for human PMN, C5-derived peptides and FMLP reduce the adherence of PMN to endothelial monolayers. Only at concentrations that decrease PMN migration do C5a and FMLP augment PMN adherence.

Adult↗
PubMed1986

Reduction of total hemolytic complement activity with Naja haje cobra venom factor does not prevent endotoxin-induced lung injury in sheep.

We studied the effects of reducing total hemolytic complement activity with Naja haje cobra venom factor on the lung injury caused by intravenously infused endotoxin in 5 unanesthetized sheep with lung lymph fistulas. In normal sheep, infusions of lipopolysaccharide W from Escherichia coli (1.0 micrograms/kg) intravenously over 30 min caused increases in protein-rich lung lymph flow as well as the appearance in plasma and lung lymph of complement (C5)-derived chemotactic activity for polymorphonuclear leukocytes. Reduction of total hemolytic complement activity by treatment with Naja haje cobra venom factor (12 to 17 U/kg intraperitoneally) did not prevent the lung injury caused by endotoxin and also did not prevent the appearance in plasma and lung lymph of chemotactic activity. We conclude that although complement appears to be activated following intravenously infused endotoxin in sheep, a completely intact complement system is not necessary for endotoxin-induced lung injury.

Animals↗
PubMed1986

Attachment of human C5a des Arg to its cochemotaxin is required for maximum expression of chemotactic activity.

The chemotactic activity of human C5a des Arg is enhanced significantly by an anionic polypeptide (cochemotaxin) in normal human serum and plasma. We have found that the cochemotaxin attaches to the oligosaccharide chain of native C5a des Arg to form a complex with potent chemotactic activity for human polymorphonuclear leukocytes. Although capable of enhancing the chemotactic activity of native C5a des Arg, the cochemotaxin had no effect on the chemotactic activity of either deglycosylated C5a des Arg, native C5a, or N-formyl-methionyl-leucyl-phenylalanine. Of the known components of the oligosaccharide chain, only sialic acid prevented enhancement by the cochemotaxin of the chemotactic activity exhibited by native C5a des Arg. Sialic acid also prevented the formation of C5a des Arg-cochemotaxin complexes, detected by acid polyacrylamide gel electrophoresis, molecular sieve chromatography on polyacrylamide gels, and sucrose density gradient ultracentrifugation.

Anaphylatoxins↗
PubMed1985

Leukotriene B4 omega-hydroxylase in human polymorphonuclear leukocytes. Suicidal inactivation by acetylenic fatty acids.

Human polymorphonuclear leukocytes (PMN) not only generate and respond to leukotriene B4 (LTB4), but also catabolize this mediator of inflammation rapidly and specifically by omega-oxidation (probably due to the action of a cytochrome P-450 enzyme). To develop pharmacologically useful inhibitors of the LTB4 omega-hydroxylase in human PMN, we devised a general scheme for synthesizing terminal acetylenic fatty acids based on the "acetylenic zipper" reaction. We found that the LTB4 omega-hydroxylase in intact PMN and in PMN sonicates is inactivated in a concentration-dependent fashion by terminal acetylenic analogues of lauric, palmitic, and stearic acids (i.e. 11-dodecynoic, 15-hexadecynoic, and 17-octadecynoic acids). Consistent with a suicidal process, inactivation of the LTB4 omega-hydroxylase requires molecular oxygen and NADPH, is time-dependent, and follows pseudo-first-order kinetics. Inactivation of the omega-hydroxylase by acetylenic fatty acids also is dependent on the terminal acetylenic moiety and the carbon chain length. Saturated fatty acids lacking a terminal acetylenic moiety do not inactivate the omega-hydroxylase. In addition, the two long-chain (C16, C18) acetylenic fatty acids inactivate the omega-hydroxylase at much lower concentrations (less than 5.0 microM) than those required for inactivation by the short-chain (C12) terminal acetylenic fatty acid (100 microM). Potent suicidal inhibitors of the LTB4 omega-hydroxylase in human PMN will help elucidate the roles played by LTB4 and its omega-oxidation products in regulating PMN function and in mediating inflammation.

Calcimycin↗
PubMed1985

Lipopolysaccharide tolerance inhibits eye inflammation. I. Reduced immune complex or lipopolysaccharide effects.

The effect of endotoxin tolerance on ocular inflammation was studied in rabbits. A single intravenous (IV) injection of endotoxin (bacterial lipopolysaccharide [LPS]) produced a mild acute iridocyclitis. Repeated daily (five to seven days) IV injections of LPS (5 micrograms extracted from Salmonella typhimurium) led to a state of refractoriness or LPS "tolerance," and ocular inflammation was no longer produced. In contrast to controls, in rabbits tolerant to LPS, IV LPS failed to elevate prostaglandin E2, thromboxane B2, or chemotactic factors in the aqueous humor. Rabbits tolerant to LPS also resisted the increase in vascular permeability normally induced by an ocular reversed passive Arthus reaction. These results demonstrated that LPS tolerance can induce anti-inflammatory effects in the eye.

Acute Disease↗
PubMed1985

Endotoxin tolerance diminishes certain antiinflammatory effects of endotoxin.

Endotoxin (bacterial lipopolysaccharide, LPS) is paradoxically both inflammatory and antiinflammatory. A single intravenous injection of 100 micrograms Escherichia coli LPS markedly inhibits the inflammatory changes associated with cutaneous reversed passive Arthus (RPA) reactions in New Zealand white rabbits. Polymorphonuclear (PMN) leukocytes from LPS-treated rabbits exhibit diminished responsiveness in vitro to complement (C5) -derived peptides. Repeated injections of LPS render animals "tolerant", that is, refractory to the toxic and inflammatory effects of LPS. We examined whether tolerance would enhance the ability of LPS to inhibit inflammation not attributable to LPS. Surprisingly, as compared with rabbits receiving a single dose of LPS, tolerant rabbits demonstrated greater inflammatory changes (i.e., PMN exudation, vascular permeability) associated with RPA reactions. PMNs from LPS-tolerant rabbits responded in vitro to C5-derived peptides significantly more than PMNs from rabbits that received a single dose of LPS. We speculate that some antiinflammatory effects of LPS require the toxic or inflammatory effects of LPS itself. These observations might relate to the limited efficacy of fever therapy and the variable effects of gram-negative sepsis on functions of human PMNs.

Animals↗
PubMed1985

Endotoxin-induced selective dysfunction of rabbit polymorphonuclear leukocytes in response to endogenous chemotactic factors.

To assess the mechanism and specificity of polymorphonuclear leukocyte (PMN) dysfunction induced by endotoxin, rabbits were injected intravenously with 100 micrograms of Escherichia coli endotoxin, and PMN function was studied 18 to 24 h later. Compared to PMN from normal rabbits, peripheral blood PMN from rabbits injected with endotoxin showed diminished chemotactic responsiveness to two endogenous peptides, C5a (complement) and platelet-derived growth factor, and to two endogenous lipids, leukotriene B4 and platelet-activating factor. The chemotactic response to the synthetic chemotactic peptide, N-formyl-methionyl-leucyl-phenylalanine (FMLP), was unimpaired. In contrast to migration, endotoxin injection resulted in inhibition of the secretory response to the two endogenous peptides but not to the lipids or to FMLP. At a 1:4 (vol/vol) dilution, the plasma either 1 or 24 h after the endotoxin injection inhibited normal PMN chemotactic responses to C5a but not to FMLP. Similarly, at a 1:10 dilution, this plasma inhibited normal PMN chemotactic responses to leukotriene B4. The factor responsible for inhibiting responses to leukotriene B4 was anionic, specific for leukotriene B4 responses, and greater than 12,000 daltons. These data may be relevant to understanding PMN dysfunction during gram-negative sepsis.

Animals↗
PubMed1985

Leukotriene B4 omega-hydroxylase in human polymorphonuclear leukocytes. Partial purification and identification as a cytochrome P-450.

Human polymorphonuclear leukocytes (PMN) not only synthesize and respond to leukotriene B4 (LTB4), but also catabolize this mediator of inflammation rapidly and specifically by omega-oxidation. To characterize the enzyme(s) responsible for omega-oxidation of LTB4, human PMN were disrupted by sonication and subjected to differential centrifugation to yield membrane, granule, and cytosol fractions (identified by biochemical markers). LTB4 omega-hydroxylase activity was concentrated (together with NADPH cytochrome c reductase activity) only in the membrane fraction (specific activity increased 10-fold as compared to whole sonicates, 41% recovery). Negligible activity was detected in granule or cytosol fractions. LTB4 omega-hydroxylase activity in isolated PMN membranes was linear with respect to duration of incubation and protein concentration, was maximal at pH 7.4, had a Km for LTB4 of 0.6 microM, and was dependent on oxygen and on reduced pyridine nucleotides (apparent Km for NADPH = 0.5 microM; apparent Km for NADH = 223 microM). The LTB4 omega-hydroxylase was inhibited significantly by carbon monoxide, ferricytochrome c, SKF-525A, and Triton X-100, but was not affected by alpha-naphthoflavone, azide, cyanide, catalase, and superoxide dismutase. Finally, isolated PMN membranes exhibited a carbon monoxide difference spectrum with a peak at 452 nm. Thus, we have partially purified the LTB4 omega-hydroxylase in human PMN and identified the enzyme as a membrane-associated, NADPH-dependent cytochrome P-450.

Cell Fractionation↗
PubMed1985

Treatment of a patient with chronic bronchial asthma with many bronchoscopies and lavages using acetylcysteine: a case report.

This Case Report is that of a young woman followed for 21 years, whose life was saved repeatedly by bronchoscopy and lavage to remove mucous plugs and casts from the tracheobronchial tree. In 1982, after again having a respiratory crisis and not having a bronchoscopy and lavage, she died. The pathology revealed a thickened hyalinized basement membrane and numerous mucous plugs filling the larger bronchi and bronchioles.

Acetylcysteine↗
PubMed1985

Chemotactic responses of human peripheral blood monocytes to the complement-derived peptides C5a and C5a des Arg.

We examined responses of human peripheral blood polymorphonuclear leukocytes (PMN) and monocytes to the highly purified human complement-derived peptides C5a and C5a des Arg. As reported previously, C5a proved to be approximately 10- to 20-fold more potent than C5a des Arg as a chemoattractant for human PMN. C5a also was more potent than C5a des Arg in causing PMN to acquire a polarized morphology. In contrast, we found that human monocytes do not distinguish between C5a and C5a des Arg when these peptides are used as chemoattractants. In two different assay systems, both peptides acted at identical concentrations to stimulate suboptimal and optimal migration of monocytes. Human monocytes also did not distinguish between C5a and C5a des Arg when these peptides were used as inducers of polarization. Studies performed with functionally active, [125I]-labeled C5a and C5a des Arg, however, demonstrated that binding of C5a des Arg to monocytes differed from binding of C5a. Although [125I]-C5a des Arg appeared to bind to the same receptor as [125I]-C5a, binding of labeled C5a des Arg occurred with an affinity that was approximately 100-fold less than that observed with labeled C5a. These results indicate that leukocyte chemotactic and polarization responses to C5a and C5a des Arg vary, depending on the target cell type.

Adult↗
PubMed1985

Adherence of human polymorphonuclear leukocytes to endothelial monolayers: effects of temperature, divalent cations, and chemotactic factors on the strength of adherence measured with a new centrifugation assay.

Polymorphonuclear leukocytes (PMNs) adhere to endothelial cells at sites of acute inflammation. To examine this phenomenon in vitro, we have developed a new assay to measure adherence of PMNs to cultured endothelial cells. Human PMNs were labeled with 111indium-oxine and incubated in microtiter wells with monolayers of either human umbilical vein or bovine aortic endothelial cells. Following incubation, the wells were sealed, inverted, and centrifuged at varying speeds. Results are expressed as the percentage of PMNs added initially that remained attached to the monolayers after being subjected to dislodgment forces (ie, relative centrifugal forces) ranging from 1 to 1,200 g. Adherence of PMNs to endothelial monolayers was temperature dependent, dependent on the concentration of extracellular Mg2+ (but not Ca2+), and enhanced significantly by the chemotactic peptides, N-formyl-methionyl-leucyl-phenylalanine (fMLP) and human C5a. It was found that fMLP and C5a not only increased the number of PMNs that adhered to endothelial cells, but also increased the strength of adherence.

Animals↗
PubMed1985

Use of acetylcysteine in bronchial asthma--another look.

Acetylcysteine is a potent mucolytic agent. When utilized as a 10% solution with a bronchodilator by pressure machine, clearance of tracheobronchial secretions can be achieved in asthmatic subjects without inducing bronchospasm.

Acetylcysteine↗
PubMed1984

Carbon monoxide inhibits omega-oxidation of leukotriene B4 by human polymorphonuclear leukocytes: evidence that catabolism of leukotriene B4 is mediated by a cytochrome P-450 enzyme.

Carbon monoxide significantly inhibits omega-oxidation of exogenous leukotriene B4 to 20-OH-leukotriene B4 and 20-COOH-leukotriene B4 by unstimulated polymorphonuclear leukocytes as well as omega-oxidation of leukotriene B4 that is generated when cells are stimulated with the calcium ionophore, A23187. Inhibition of omega-oxidation by carbon monoxide is concentration-dependent, completely reversible, and specific. Carbon monoxide does not affect synthesis of leukotriene B4 by stimulated polymorphonuclear leukocytes or other cell functions (i.e., degranulation, superoxide anion generation). These findings suggest that a cytochrome P-450 enzyme in human polymorphonuclear leukocytes is responsible for catabolizing leukotriene B4 by omega-oxidation.

Calcimycin↗
PubMed1984

Omega-oxidation is the major pathway for the catabolism of leukotriene B4 in human polymorphonuclear leukocytes.

Leukotriene B4 (LTB4), formed by the 5-lipoxygenase pathway in human polymorphonuclear leukocytes (PMN), may be an important mediator of inflammation. Recent studies suggest that human leukocytes can convert LTB4 to products that are less biologically active. To examine the catabolism of LTB4, we developed (using high performance liquid chromatography) a sensitive, reproducible assay for this mediator and its omega-oxidation products (20-OH- and 20-COOH-LTB4). With this assay, we have found that human PMN (but not human monocytes, lymphocytes, or platelets) convert exogenous LTB4 almost exclusively to 20-OH- and 20-COOH-LTB4 (identified by gas chromatography-mass spectrometry). Catabolism of exogenous LTB4 by omega-oxidation is rapid (t1/2 approximately 4 min at 37 degrees C in reaction mixtures containing 1.0 microM LTB4 and 20 X 10(6) PMN/ml), temperature-dependent (negligible at 0 degrees C), and varies with cell number as well as with initial substrate concentration. The pathway for omega-oxidation in PMN is specific for LTB4 and 5(S),12(S)-dihydroxy-6,8,10,14-eicosatetraenoic acid (only small amounts of other dihydroxylated-derivatives of arachidonic acid are converted to omega-oxidation products). Even PMN that are stimulated by phorbol myristate acetate to produce large amounts of superoxide anion radicals catabolize exogenous leukotriene B4 primarily by omega-oxidation. Finally, LTB4 that is generated when PMN are stimulated with the calcium ionophore, A23187, is rapidly catabolized by omega-oxidation. Thus, human PMN not only generate and respond to LTB4, but also rapidly and specifically catabolize this mediator by omega-oxidation.

Arachidonic Acid↗