CXC chemokines play a central role in regulation of neutrophil activation and chemotaxis. Because the chemotactic responses of neutrophils are impaired after phagocytosis, we explored the effect of phagocytic stimuli on the expression of interleukin-8 (IL-8) receptors, CXCR1 and CXCR2, in human neutrophils. After phagocytosis of opsonized yeast, the expression of CXCR1 and CXCR2 was substantial...

Human polymorphonuclear leukocytes (PMN) migrate into tissues in response to chemoattractants, yet it is not known whether this process alters the functional capabilities of the PMN. Using recombinant human interleukin-8 (rHIL-8, 100 ng/ml) as a stimulus, we compared a population of PMN that migrated through a polyvinylpyrrolidone-coated polycarbonate filter containing 8.0 microns diameter pore...

The granulocyte-specific monoclonal antibody, AHN-1, immunoprecipitates two major surface-iodinated proteins of 105,000 and 145,000 to 150,000 daltons from normal human neutrophils. In this study, the effect of AHN-1 on a number of neutrophil functions was evaluated in vitro. Both complement- and antibody-mediated phagocytosis were inhibited when human neutrophils were pretreated with AHN-1 and...

Chemotaxis of bacteria requires regulated methylation of chemoreceptors. However, despite considerable effort in the 1980s, transmethylation has never been established as a component of eukaryotic cell chemotaxis. S-adenosylhomocysteine (SAH), the product formed when the methyl group of the universal donor S-adenosylmethionine (SAM) is transferred to an acceptor molecule, is a potent inhibitor ...

Monocytes and macrophages belong to the mononuclear phagocyte system play important roles in both physiological pathological processes. The cells belonging monocyte/macrophage are structurally functionally heterogeneous. Several subsets of monocytes have been previously identified mammalian blood, generating different subpopulations tissues. Although their distribution phenotype similar human c...

We studied the effects of two diazepam-binding inhibitor (DBI)-derived peptides, triakontatetraneuropeptide (DBI 17-50, TTN) and eiksoneuropeptide (DBI 51-70, ENP), on cytosolic free Ca2+ concentrations ([Ca2+]i), chemotaxis, superoxide anion (O2-) generation, and phagocytosis in human neutrophils. Both TTN and ENP induced a rapid and transient rise of [Ca2+]i. The effect of TTN depended on the...

Electronic (e-) cigarettes are growing in popularity despite uncertainties regarding their long-term health implications. The link between cigarette smoking and initiation of chronic lung disease took decades to unpick so vitro studies mimicking e-cigarette exposure aim detect early indicators harm. In response exposure, alveolar macrophages adopt a proinflammatory phenotype increased secretion...