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J Hakim

Publications and source records attributed to J Hakim.

At least 109 records · Page 6Linked to original sources
PubMed1987

Cefodizime (HR 221) potentiation of human neutrophil oxygen-independent bactericidal activity.

The enhanced bactericidal activity of human neutrophils induced by cefotaxime and cefodizime, two methoxy-imino-amino- 2-thiazolyl cephalosporins, is linked to the cell stimulation of oxygen-dependent and oxygen-independent killing systems, respectively. Cefotaxime enhances both the killing and the oxidative response of neutrophils to opsonized particulate stimuli (bacteria for both activities and opsonized zymosan for the oxidative burst). These effects were not observed with non-opsonized particles (bacteria or zymosan) or soluble stimuli. On the contrary, cefodizime enhances killing of opsonized and non-opsonized bacteria by neutrophils regardless of treatment with phenylbutazone which blocks neutrophil oxidative metabolism. Cefodizime does not universally alter the oxidative burst induced by various stimuli, but has been shown to enhance the bactericidal activity of crude extracts of neutrophil granules. The data suggest that cefodizime and non O2-dependent killing systems of neutrophils cooperate in killing bacteria.

Cefotaxime↗
PubMed1987

Interaction of ceftriaxone with human polymorphonuclear neutrophil function.

Ceftriaxone, an amino-2-thiazolyl cephalosporin, has been shown to cooperate in vitro with human neutrophils for the killing of some bacteria. In this work the direct interaction with human leucocyte bactericidal function has been studied. Ceftriaxone (1000 to 1 mg/l) did not alter neutrophil chemotaxis or superoxide anion production. It also did not interfere with the chemiluminescence response of isolated PMN although a paradoxical depressive effect was observed with whole human blood in the case of zymosan stimulation. The killing of Staphylococcus aureus and Klebsiella pneumoniae was not enhanced by ceftriaxone and phagocytosis was significantly depressed only with adherent neutrophils but not when using neutrophils in liquid medium. It is concluded that the synergy observed between leucocyte and ceftriaxone for bacterial killing cannot be related to a direct stimulation of neutrophil functions and should depend on bacterial alteration.

Blood Bactericidal Activity↗
PubMed1987

Effect of ceftriaxone-induced alterations of bacteria on neutrophil bactericidal function.

Two bacterial strains (Staphylococcus aureus and Klebsiella pneumoniae) were exposed to subinhibitory concentrations of ceftriaxone. After an overnight culture in presence of 1 MIC of ceftriaxone either in broth or on solid medium S. aureus showed enlarged forms which were better phagocytosed (increase about 40%) and killed (increase about 50%) than control staphylococci. Exposure of K. pneumoniae to 0.1 MIC ceftriaxone resulted in filamentation of bacteria. When grown in the presence of 0.01 MIC, K. pneumoniae did not elongate into filaments but were significantly more phagocytosed (increase about 40%) or killed (increase about 170%) than control bacilli. The mechanism of the greater sensitivity to PMN killing of the altered S. aureus and K. pneumoniae was assessed either with phenylbutazone-treated PMN or by in-vitro exposure to crude granule extracts of PMN. The altered bacteria displayed a significant susceptibility to the non-oxidative killing mechanism while untreated bacteria were unaffected by the non-oxidative system. These data could explain the synergy observed between ceftriaxone and leucocytes in the killing of some micro-organisms.

Blood Bactericidal Activity↗
PubMed1987

Functional effects of monoclonal antibodies (mAbs) against human polymorphonuclear (PMN) adherence antigens.

Two mouse monoclonal antibodies (mABs), 25.31 raised against an subunit epitope of LFA1 antigen and Mol against an epitope of the complement receptor type 3 (CR3) were used for investigating their effects on human polymorphonuclear (PMN) functions. The two mABs have an inhibitory effect on PMN adherence. Furthermore, the PMN adherence strength depends upon the support and the adherence induces the capping process of these antigens. Other PMN functions dependent upon adherence were also altered by these two mAbs: random locomotion and that directed by formyl-methionyl-leucyl-phenylalanine (FMLP) or by activated serum, degranulation induced by opsonized or non opsonized zymosan but not by phorbol myristate acetate (PMA), iodination, K562 cell cytotoxicity. Luminol enhanced chemiluminescence of PMN was diminished by both mAbs when PMN were stimulated either by opsonized zymosan or by PMA. Our results confirm other workers' findings, and they are consistent with PMN functional abnormalities observed in children with congenital LFA1, Mol antigens defect.

Antibodies, Monoclonal↗
PubMed1987

Comparison of blocking effects of monoclonal antibodies anti-MO1-alpha and anti-LFA1-alpha on human neutrophil functions.

In order to analyse the role of LFA1 and MO1 on neutrophil functions, the blocking effects of two monoclonal antibodies (MAb), one (anti-MO1) recognizing an epitope of the MO1-alpha chain and the other (25.31) an epitope of the LFA1-alpha chain, were measured. Adherence of 51Cr-labelled control neutrophils was 66 + 8% (mean +/- 1 SD) on plastic nuclon plates; this figure decreased to 33 +/- 5% and 23 +/- 6% of control adherence when the neutrophils had been pretreated with anti-LFA1-alpha (anti-alpha L) and anti-MO1-alpha (anti-alpha M), respectively. On another support (plastic culture chambers), 84 +/- 6% of control neutrophils adhered and the adherence of neutrophils pretreated with anti-alpha L or anti-alpha M was 10% and 43% of the control figure, respectively. These results show that adherence of neutrophils is dependent upon the plastic used. Moreover, inhibition of adhesion by the two MAbs was also dependent upon the support used for the assay, suggesting that MO1 and LFA1 may be surface proteins with different specificities. Both antigens capped upon adhesion, while they were randomly distributed in resting neutrophils. Anti-alpha L inhibited (congruent to 50%) locomotion more than did anti-alpha M (congruent to 25%), without altering chemoattractant-induced shape changes. These results suggest that the two MAbs inhibit chemokinesis but not chemotaxis. Many other adherence-associated functions, such as ingestion of opsonized Klebsiella pneumoniae, and cytotoxicity towards K/562 cells were decreased more by anti-alpha L than by anti-alpha M. In contrast, chemiluminescence and iodination induced by opsonized zymosan were inhibited more by anti-alpha M than by anti-alpha L. Degranulation induced by zymosan or opsonized zymosan was altered by anti-alpha M only, and this alteration involved azurophilic and not specific granules. Chemiluminescence induced by phorbol myristate acetate was inhibited to a greater extent by anti-alpha M than by anti-alpha L, while degranulation induced by phorbol myristate acetate was not altered by either of the two Mabs.

Adult↗
PubMed1987

[Adhesiveness and membrane glycoproteins of human polynuclear neutrophils].

Clinical and biological features of a recently recognized inherited syndrome are reported. This syndrome, Leukocyte Adherence Deficiency, is characterized by recurrent, life-threatening infections. The increased susceptibility to infectious agents is mainly related in the inability of the leukocytes to adhere to certain surfaces, because all adherence-related functions of the neutrophils that lead to bacterial killing are impaired. Adherence deficiency is due to moderate or severe deficiency of three structurally related glycoproteins (MO1, LFA-1 and gp 150,95). All three glycoproteins are heterodimers and share a common subunit whose absence is the cause of the disease.

Antigens, Surface↗
PubMed1987

Nonsteroidal anti-inflammatory drug as tools for analysis of neutrophil functions.

We investigated the effects of the nonsteroidal anti-inflammatory drugs diclofenac sodium, indomethacin and phenylbutazone on the activities relating to the migration and respiratory burst of polymorphonuclear leukocytes (PMN). When diclofenac sodium, was incorporated into the agarose gel at various concentrations below 100 micrograms/ml, it inhibited, in a dose-dependent fashion, spontaneous PMN migration and the directional migrations induced by both C5a-activated serum and peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP). By contrast, phenylbutazone (below 100 micrograms/ml) only altered the directed PMN migration induced by FMLP, in two characteristic ways: by impairing the optimal response to 10(-7) M FMLP, and in particular, by restoring the loss of migration induced by higher but deactivating concentrations of 10(-6) and 10(-5) M. Indomethacin had similar effects to those of phenylbutazone on FMLP-induced PMN migration and in addition slightly impaired spontaneous PMN migration. The alterations in FMLP-induced migration caused by the three drugs tested were mainly chemokinetic and were due to changes in migratory speed. Of the three drugs, phenylbutazone and indomethacin also impaired FMLP-induced changes in the shape of PMN. All three interfered with the respiratory burst induced by FMLP but not with that induced by phorbol myristate acetate. These results demonstrate that phenylbutazone, indomethacin and diclofenac possess different spectra of biological activities as regards the parameters relating to PMN migration and respiratory burst, and therefore suggest that these drugs could serve as tools for investigating PMN functions.

Adult↗
PubMed1987

Inhibitory effect of K-562 malignant cells on locomotion of human neutrophils.

Certain tumor cells generate factors that inhibit neutrophil chemotaxis. The present study was designed to explore, in K-562 malignant cells, the release of such factors that may alter the neutrophil locomotion. The supernatant, separated from the K-562 malignant cells cultured in vitro for 48 hours, was lyophilised and extracted with ethanol 80%. This ethanol extract (SE-K562) inhibited neutrophil locomotion. Both random and locomotion induced either by formyl-methionyl-leucyl-phenylalanine (FMLP) or serum were inhibited. SE-K562 was partially purified by Sephadex chromatography and the analysis of the eluted active fraction by SDS electrophoresis led one band of about 8 kd. No one inhibitory effect was observed with appropriate controls. In conclusion, K562 malignant cells in culture release a low molecular weight factor (8 kd) that inhibits all forms of PMN locomotion i.e. random locomotion and locomotion induced either by FMLP or serum.

Cell Line↗
PubMed1986

Effect of doxycycline on oxygen-dependent killing mechanisms of human neutrophils.

The effects of doxycycline on neutrophil adhesivity, ingestion rate, and oxidative burst by particle and soluble compounds have been analyzed. The rate of bacterial ingestion by neutrophils as well as its subsequently particle-induced oxidative burst comprising oxygen uptake, hydrogen peroxide and superoxide anion productions, and iodination were all inversely correlated to doxycycline concentration included in the assay medium. The neutrophil oxidative burst induced by phorbol myristate (a soluble stimulant) was also inversely correlated to doxycycline concentration. Drug effect was observed at lower concentrations when the neutrophil stimulant was a soluble compound than when it was particles. In contrast doxycycline did not affect neutrophil adhesivity to either nylon fibers or Petri dishes. Further studies are needed to assess whether the activity of the drug on the neutrophil is due only to its ability to chelate calcium and magnesium or to other properties.

Cell Adhesion↗
PubMed1986

Plasma membranes of human neutrophils: a one-step isolation procedure by cell disruption in paraffin oil.

Plasma membranes of high purity and good yield have been prepared from human polymorphonuclear neutrophils by a one-step procedure involving disruption of cells suspended in paraffin oil and forced by pressure through an annular slit. This results in a band floating above the oil which is composed of large sheets of plasma membranes. Enrichment values for the plasma membrane marker alkaline phosphatase and 125I-labeled protein after surface labeling performed at the whole cell level were 23-fold and 22-fold, respectively. Contamination of the plasma membrane by other organelles was negligible and approximately 2 mg of membrane protein was obtained from 10(9) neutrophils. The procedure is very fast and the use of paraffin oil avoids lengthy high-speed centrifugation. The technique also allows isolation of granules devoid of plasma membrane and can probably be applied to other cell types.

Adult↗
PubMed1986

Effect of degranulation on superoxide dismutase activity in human neutrophils.

Resting neutrophils possess cytosolic cyanide-sensitive (CNs) superoxide dismutase (SOD) and cyanide-insensitive (CNi) SOD, located in an undefined organelle of the 27,000 g sedimentable fraction of its homogenate. Stimulated neutrophils generate large amounts of superoxide anion, part of which is released in the extracellular medium and contributes to changes that occur in inflammatory foci. Our purpose was to assess whether or not the neutrophil upon stimulation secreted either or both CNs and CNi SOD activity, because the process could protect against the release of superoxide anion. Human neutrophils stimulated in vitro with phorbol myristate acetate released 32.6% and 53% of their content in myeloperoxidase (an azurophilic granule marker) and vitamin B12 binding activity, respectively. The CNi SOD was not secreted at all, whereas 16% and 23% of CNs SOD were released by resting and stimulated neutrophils, respectively. In contrast, lactate dehydrogenase, a cytosolic marker, was released by both resting and stimulated cells (approximately equal to 9%). These results suggest that CNi SOD is not located in the granules but in another organelle that does not degranulate upon stimulation and consequently does not protect against superoxide anion formed by neutrophils in the extracellular medium. In contrast, CNs SOD is slightly but significantly released (P less than .02) and may be protective. Neutrophils from two patients with chronic granulomatous disease behaved similarly to control neutrophils but their content of both types of SOD was higher than that of the controls.

Cytochalasin B↗
PubMed1986

Effects of cefotaxime and cefodizime on human granulocyte functions in vitro.

In vitro, cefotaxime and cefodizime enhanced significantly the bactericidal activity of human neutrophils against Staphylococcus aureus P 209 A, but not phagocytosis. The increase was about 150% for cefotaxime and 400% for cefodizime at concentrations as low as 1 mg/l. Furthermore, by two different techniques (NBT and cytochrome C reduction tests) cefotaxime but not cefodizime significantly enhanced superoxide anion production by zymosan-stimulated neutrophils. Other neutrophil functions (chemotaxis and myeloperoxidase-mediated iodination of proteins) were not significantly altered by either antibiotic, even at concentrations as high as 1000 mg/l.

Blood Bactericidal Activity↗
PubMed1986

Discoid lupus erythematosus-like lesions in an autosomal form of chronic granulomatous disease.

Chronic granulomatous disease (CGD) is characterized by a bactericidal defect involving the oxidative metabolism of polymorphonuclear leukocytes (PML) and is most often transmitted as an X-linked trait. The cutaneous features of this disorder include infections and lupus-like rashes. These have been described in female carriers as well as in males with the disease. Two cases of siblings presenting an autosomal form of CGD syndrome, with lupus-like cutaneous manifestations, are reported here.

Adolescent↗
PubMed1986

Synergy between RU 28965 (roxithromycin) and human neutrophils for bactericidal activity in vitro.

The in vitro effects of RU 28965 (roxithromycin), a new semisynthetic macrolide, on human neutrophil activity were compared with those of erythromycin. RU 28965, at a concentration as low as 0.1 microgram/ml, significantly enhanced the phagocytosis and killing of Staphylococcus aureus by neutrophils. Erythromycin displayed a less stimulating effect in a dose-dependent manner. Phagocytosis of Klebsiella pneumoniae was also increased after incubation of neutrophils with RU 28965, but killing was not altered. Neutrophil chemotaxis, myeloperoxidase activity, and O2 consumption were unchanged in the presence of RU 28965.

Blood Bactericidal Activity↗
PubMed1985

Diclofenac sodium, a negative chemokinetic factor for neutrophil locomotion.

Diclofenac sodium, a non steroidal anti-inflammatory agent, was studied for its influence on the locomotion of human polymorphonuclear neutrophils (PMN), in an attempt to define the mechanism governing the drug's anti-inflammatory properties. PMN locomotion was measured by the agarose technique under two conditions of stimulation of cell migration: in the presence of a gradient of stimuli (chemotaxis) and in the presence of various amounts of stimuli incorporated in the gel (chemokinesis). At concentrations below 10 micrograms/ml, diclofenac in the gel reduced, in a dose-dependent manner, the directed locomotion of PMN induced by a gradient of C5a-activated serum, peptide N-formyl-methionyl-leucyl-phenylalanine (FMLP) or Klebsiella pneumoniae culture supernatant (KPCS). Diclofenac also inhibited the random locomotion of unstimulated PMN, as well as the PMN chemokinetic activity induced by various amounts of FMLP or activated serum. Inhibition of PMN locomotion by diclofenac decreased when the concentration of the stimulant was raised; this inhibition was inversely related to the concentration of heat-inactivated fetal calf serum in the medium. The directed locomotion and chemokinesis of PMN, induced by FMLP were also reduced in PMN preincubated with diclofenac before migration, suggesting a direct cellular effect of diclofenac. On the other hand, diclofenac did not affect the changes in shape induced in floating PMN by FMLP or activated serum. The observation that diclofenac did not alter the ingestion rate of bacteria by PMN indicates that this drug is not cytotoxic for PMN. Consequently, diclofenac reduces PMN locomotion by interfering with the PMN chemokinetic activity. Diclofenac is an anti-inflammatory drug possessing the original property of acting as a negative chemokinetic agent, for migration of both stimulated and unstimulated PMN. It should therefore be a useful tool for analyzing the elements controlling PMN locomotion speed.

Blood↗
PubMed1985

Spectroscopic interference of hemoglobin with neutrophil cytochrome b-245 and its elimination by carbon monoxide.

A cytochrome b, designated as cytochrome b-245, exists in neutrophils and is probably involved in their stimulated oxidative burst. As a rule, its concentration is spectroscopically measured by the height of its alpha-peak at 558-559 nm (dithionite-reduced minus oxidized). Hemoglobin (Hb), which usually contaminates neutrophils isolated from blood, interferes with the spectroscopic measurement of the cytochrome. Hb contamination from less than 0.4 red blood cells per 100 neutrophils leads to over-estimation of the cytochrome by approximately 50%. This interference can be overcome by bubbling CO through neutrophil homogenates heavily contaminated by Hb, prior to the conventional spectroscopic procedure. The cytochrome B-245 concentration obtained in neutrophils by CO bubbling is 7.2 +/- 1.28 pmoles per 10(6) polymorphonuclear neutrophils.

Carbon Monoxide↗
PubMed1985

Effect of acute nonimmune inflammation on locomotion of exudate and blood rabbit neutrophils.

The random and directed locomotion of rabbit polymorphonuclear neutrophils (PMNs) were investigated in vitro by the agarose technique. PMNs were either recruited in serum-elicited pleural exudates or isolated from blood collected before or after pleurisy development. Directed PMN migration was assessed in the presence of N-formyl-methionyl-leucyl-phenylalanine (FMLP), isologous rabbit serum (IRS) or cell-free exudates as chemotactic stimuli. Neutrophils collected from blood before pleurisy induction or 4 h afterwards displayed similar random migration, and similar migration oriented by FMLP, IRS, or cell-free exudates. However, both random and FMLP-induced migration were greater for exudate than blood PMNs. In the presence of IRS or cell-free exudate as chemoattractants, exudate and blood PMNs migrated over similar distances. These results suggest that exudation does not deactivate elicited PMNs but alters their locomotion responses according to the stimulus applied.

Animals↗