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Polymorphonuclear neutrophils (PMN) play a central role in the acute inflammatory response and functions associated with phagocytosis and bacterial killing, including lysosomal enzyme release and superoxide anion (O2-) generation, are also implicated in tissue injury. We have studied the modulation by chlorpromazine (CPZ) on the effects of lipopolisaccharide (LPS) in vivo in mice. Pretreatment with CPZ (4 mg/kg) and, to lesser extent, promethazine, inhibited LPS-induced hypofaerremia and lethality in mice. We have also observed that CPZ (1-15 µM) inhibited lactoferrin release by PMN in vitro, suggesting that this effect could be responsible for the inhibition of hypoferraemia. We have also evaluated the effect of CPZ on other PMN functions implicated in tissue damage and inflammation, chemotaxis and O2- production. CPZ inhibited both activities, although it had chemokinetic activity per se. These data indicate that CPZ is a modular of PMN functions in vivo and in vitro and this effect could be directly implicated in the protective action of CPZ against endotoxic shock. [ABSTRACT FROM AUTHOR]

The adsorption of different types of phosphatidylglycerols onto magnetizable solid particles is studied. The super-paramagnetic magnetite spheres used have an average diameter of only 14 nm and are stabilized by lauric acid to keep them in solution. During incubation and dialysis of this water-based magnetic fluid in the presence of preformed sonicated phospholipid vescles, magnetoliposomes are formed which are captured from solution with high efficiency by high-gradient magnetophoresis. Support for the bilayer character of the phospholipid coat is derived from both theoretical calculations and experimental data. Phospholipids which form the inner monolayer are adsorbed very quickly with their charged headgroup orientated towards the iron oxide surface. The high-affinity character of the binding is reflected in the adsorption isotherms and is further illustrated by their non-extractability with high concentrations of Tween 20. The outer layer assembles through interaction with the exposed hydrocarbon chains. As compared to the inner layer, the phospholipids adsorb at a much slower rate and are displaced by Tween 20 concentrations which usually disrupt conventional membranes. The adsorption isotherms for this layer obey the Langmuir expression. The affinity constants, derived from them, progressively increase as the hydrophobic nature of the phosphatidylglycerols is more pronounced. [ABSTRACT FROM AUTHOR]

A sensitive passive haemagglutination technique is described depending on the attachment of proteins to erythrocytes with glutaraldehyde. Various factors that play a role in the coupling of bovine serum albumin to sheep erythrocytes are examined. A standard procedure was deduced by which other proteins were coupled and tested with their specific antisera. The observed titres are comparable to those obtained with the classical bis-diazotized benzidine method. The technique is specific and practicable. It provides sensitized cells that remain stable for several weeks.

The influence of human monocyte-derived chemotactic peptide (GCP/IL-8) on degranulation of neutrophils was investigated in relation to that of other monokines. GCP/IL-8 promoted a dose- dependent release of lactoferrin from specific granules but had no effect on enzyme release from primary granules. From the other monokines that were tested, tumour necrosis factor alpha (TNFα) also induced degranulation, while IL-1β and IL-6 scored negatively. TNFα-induced lactoferrin release was enhanced by cytochalasin B pretreatment of the granulocytes, while GCP/IL-8-promoted degranulation was not. In contrast to GCP, TNFα also caused the release of LDH, suggesting a non- specific cell destruction. These observations further support the view that, unlike the other monokines, GCP/ IL-8 is a true and specific granulocyte activator. [ABSTRACT FROM AUTHOR]