Patrick Kernen

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Human neutrophils pretreated with 17-hydroxywortmannin responded to the chemotactic agonist formyl-Met-Leu-Phe with a transient doubling in filamentous actin content which was characterized by prominent oscillations. These oscillations closely matched transient oscillations in suspension turbidity measured in parallel. The experimental data could be(More)
Neutrophils pretreated with phorbol 12-myristate 13-acetate (1-10 nM) and stimulated with low concentrations of chemotactic agonists (1-10nM) exhibited a marked increase in respiratory burst activity that was characterized by regular oscillations. These were accompanied by parallel oscillations in turbidity having the same phase and period. Four different(More)
The rise in cytosolic free Ca2+, shape change, superoxide formation, and granule exocytosis induced in human neutrophils by N-formyl-Met-Leu-Phe (fMLP) and by a newly discovered activating peptide, neutrophil-activating factor, termed NAF, were compared. NAF was effective in the concentration range of 0.1-10 nM and was 10- to 100-fold more potent than fMLP.(More)
Human neutrophils treated with the secretion inhibitor 17-hydroxywortmannin were stimulated with fMLP, C5a, PAF or LTB4, and the ensuing shape change was studied. The cells rapidly extended lamellipodia and showed regular oscillatory behaviour. The oscillations were observed in both light transmission and 90 degrees light scattering, had the same frequency(More)
Essentially pure preparations of normal density eosinophils obtained from patients with hypereosinophilic syndrome (HES) were stimulated with complement factor 5a (C5a), platelet-activating factor (PAF), FMLP and neutrophil-activating peptide (NAP-1/IL-8). Three responses were studied, the transient rise in cytosolic free calcium concentration ([Ca2+]i)(More)
Resting blood neutrophils are recruited at sites of infection and inflammation by chemotactic agonists that direct their migration through the vascular wall into the tissues. Diapedesis and oriented motion within the interstitial space are complex processes depending on the activation of the motile apparatus of the migrating cell as well as the release of(More)
Our studies show that stimulated human mononuclear phagocytes produce a neutrophil-activating factor (NAF). Lymphocytes do not appear to produce NAF or to influence its production. The results indicate that NAF is selective for neutrophils and induces activation via its own surface receptor through a signal transduction process to that initiated by fMLP and(More)
The activation of the respiratory burst by complement factor 5a (C5a), platelet-activating factor (PAF), formyl-Met-Leu-Phe (fMLP) and neutrophil-activating peptide IL-8 was explored in eosinophils from patients with the hypereosinophilic syndrome. The amplitude of the response increased with increasing concentrations of C5a and PAF, but the time for its(More)
In the last 12 months, two countries, France and the United States, have issued or updated safety policies regarding their munitions or insensitive munitions. At NATO, a Standardization Agreement (STANAG) regarding IM is in its final draft and incorporates standardized testing. Responses to these tests will help to decide if a munition meets safety and/or(More)
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