Co-Activation of Human Whole Blood Cells with Lipopolysaccharides and an Allergen.

The investigation of common inflammation mechanisms caused by exogenic compounds of microbial origin and allergens is one of the most important tasks in current biomedical science. The main manifestations of immune cell activation caused by pro-inflammatory agents are changes in receptor quantity on the surface of immune cells and the production of cytokines and chemokines by blood cells. The levels of expression of TLR4, CD14, and CD11b in the monocytes and neutrophils of human whole blood in response to LPS , Der p 2 allergen, or their combination reflect different functional activities in these cells, while the composition and amount of produced cytokines reflect the biological activity of the studied agonists.

Monoclonal Antibody to CD14, TLR4, or CD11b: Impact of Epitope and Isotype Specificity on ROS Generation by Human Granulocytes and Monocytes.

Lipopolysaccharides (LPSs or endotoxins) from Gram-negative bacteria represent pathogen-associated molecular patterns (PAMPs) that are recognized by CD14 and Toll-like receptor 4 (TLR4). Lipopolysaccharides prime polymorphonuclear leukocytes (PMNs) for substantial production of reactive oxygen species (ROS) during its response to secondary stimuli such as chemoattractants or pathogens. The excessive ROS production can damage surrounding host tissues, thereby amplifying the inflammatory reaction caused by pathogens.

Effect of lipopolysaccharide structure on functional response of whole blood cells.

Lipopolysaccharides (LPSs) induce a wide spectrum of functional activities after interaction with blood cells. Effect of structure of toxic LPS from S- and Re-chemotypes of E. coli and/or non-toxic LPS of Rhodobacter capsulatus PG (R.

Impact of CD14 on Reactive Oxygen Species Production from Human Leukocytes Primed by Lipopolysaccharides.

Lipopolysaccharides (LPS) from Gram-negative bacteria prime human polymorphonuclear neutrophils (PMNs) via multicomponent receptor cluster including CD14 and MD-2·TLR4 for the enhanced release of reactive oxygen species (ROS) were triggered by bacterial derived peptide -formyl-methionyl-leucyl-phenylalanine (fMLP). In this study, we investigated the impact of CD14 on LPS-induced priming of human PMNs for fMLP-triggered ROS generation (respiratory or oxidative) burst. Monoclonal antibodies against human CD14 (mAbs) as well as isotype-matched IgG2a did not influence significantly fMLP-triggered ROS production from LPS-unprimed PMNs.

Interaction of Gram-negative bacteria with cationic proteins: Dependence on the surface characteristics of the bacterial cell.

Gram-negative bacteria can enter the bloodstream and interact with serum cationic proteins. The character of interaction will depend on the surface characteristics of bacterial cells, which are determined by bacterial chemotype and density of lipopolysaccharide (LPS) packing in the cell wall. It was shown that the lysozyme treatment resulted in the increase sensitivity to hypotonic shock.