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Polymorphonuclear functions were studied in 3 patients of the same brotherhood with Papillon-Lefèvre disease (hyperkeratosis palmaris and plantaris and acute periodontosis resulting in loss of teeth) who developed severe and recurrent infections. Chemotaxis, oxygen consumption and production of H2 O2 were investigated by polarography, O2 production by quantitative reduction of nitroblue tetrazolium and iodination by the Pinus and Klebanoff technique. functional anomalies of polymorphonuclears involving chemotaxis, induced O2 consumption and H2 O2 production were detected in all three patients. This study confirms the presence of polymorphonuclear functional anomalies in patients with Papillon-Lefèvre disease. Analysis of the family tree of the patients, which went back to 1761, showed that this was probably not a chance association.

Anteroposterior inversion of lateral mesoblast of early toad neurula is followed by differentiation of diverse urogenital blastema, according to the transplant position before the graft. Anteroposterior polarity of lateral mesoderm is thus perfectly determined in young neurula. On the contrary, dorsoventral inversion of lateral mesoblast leads to mesodermic blastema formation according to the transplant position after the graft. Particularly, the dorsal region of the lateral plates displaced to ventral position does not form blastema. On the other hand, the ventral region which shows a dorsal position after the graft develops and produces a typical blastema. Thus, in the young neurula, the dorsoventral polarity is not yet determined in the lateral plate of the mesoblast. Such a result shows also that the ventral and posterior regions of the lateral mesoblast are competent to form blastema. Moreover, factors from dorsal origin and external to lateral mesoblast take part in urogenital organ anlagen formation.

Monocytes from five unrelated children (four boys and a girl) with chronic granulomatous disease were studied for their ability to reduce nitroblue tetrazolium dye after stimulation with zymosan, and for their alpha-naphtyl butyrate esterase activity. As expected, monocytes ingested zymosan particles but failed to reduce nitroblue tetrazolium dye. However, monocytes from two boys out of the five patients were alpha-naphtyl butyrate esterase-negative, whereas both their neutrophils and monocytes were positive for granular naphtol AS-D esterase activity.

The effects of 1-(5-isoquinoline sulphonyl)-2-methyl piperazine (H-7), a recently described inhibitor of Ca2+/phospholipid-dependent protein kinase (protein kinase C), were studied during under-agarose migration of human polymorphonuclear neutrophils (PMN) stimulated by various chemoattractants, in order to determine whether protein kinase C is involved in PMN locomotion. The effect of H-7 on the oxidative burst induced by phorbol 12-myristate 13-acetate or N-formyl-methionyl-leucyl-phenylalanine (FMLP) was also measured. Pre-incubation of PMN with H-7 concentrations ranging from 50 to 400 microM inhibited: (i) spontaneous PMN migration under agarose; (ii) the directed migration induced by activated serum, leukotriene B4 or FMLP; and (iii) the speed of the migration induced by FMLP. The inhibition by H-7 of FMLP-induced directed migration was less when FMLP was used at high concentrations which, in the absence of H-7, inhibit locomotion. H-7 depressed the oxidative burst induced by phorbol myristate acetate (PMA) but not that induced by FMLP. All the effects of H-7 on the oxidative burst and migration were reversed by washing PMN after H-7 treatment. These findings indicate that protein kinase C, inhibitable by H-7, is involved in a mechanism controlling the speed of PMN locomotion.

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.

The respiratory burst of human polymorphonuclear neutrophils (PMN) induced by particle or soluble stimuli was measured in the presence of the nonsteroidal anti-inflammatory drug, diclofenac sodium (Voltaren). Diclofenac (25-100 micrograms/ml) inhibited the oxygen consumption of PMN stimulated by 5 X 10(-7) M of N-formyl-methionyl-leucyl-phenylalanine (FMLP). The inhibition was linearly correlated to diclofenac concentration. By contrast, diclofenac did not affect the rate of heat-killed Klebsiella pneumoniae ingestion of PMN, or the PMN O2-uptake induced by (0.67 microgram/ml) serum-opsonized zymosan or (1 microgram/ml) phorbol myristate acetate (PMA). The PMN production of superoxide anion induced by various FMLP concentrations (10(-7), 10(-6) and 10(-5) M) was also decreased by diclofenac. However, this inhibition declined when the formylated peptide concentration was raised suggesting that diclofenac could alter FMLP binding to the PMN membrane. Binding experiments of tritiated FMLP to intact PMN performed at 22 degrees and 4 degrees showed high- and low-affinity FMLP sites with dissociation constant (Kd) values of approximately 2 X 10(-8) M and 10(-5) M respectively. Diclofenac did not significantly alter the low-affinity component but induced modifications of the high-affinity component which were different at 22 degrees and 4 degrees. At 22 degrees only the dissociation constant value was enhanced by diclofenac (competitive inhibition) whereas at 4 degrees both binding parameters (i.e. dissociation constant and number of available binding sites) were modified (mixed inhibition). Diclofenac was also shown to bind to PMN with a low affinity. This binding was not diminished at 4 degrees by various concentrations of FMLP which even increased the number of diclofenac binding sites on PMN at 22 degrees. These data suggest that diclofenac binding to PMN may decrease FMLP-induced PMN respiratory burst by interfering with the peptide recognition by specific FMLP receptors.

Phagocytes (P), i.e. neutrophils, monocytes and macrophages, may be involved as well as reactive oxygen species (ROS) in the initiation and development of atherosclerosis. Evidences for this assumption are the following; P and ROS are both able to damage endothelial cells whose dysfunction is crucial in the etiology of atherosclerosis. ROS generated by endothelial cells, smooth muscle cells or mainly blood cells such as neutrophils but also monocytes platelets and erythrocytes, peroxide directly endothelial cell membranes. Damage to cell membranes can be induced by P that adhere to, and release on endothelial cells large amounts of proteolytic and lipolytic enzymes. ROS can also induce formation in the blood of lipoperoxides which are often included in LDL (low density lipoproteins). These modified LDL are cytotoxic, possess phospholipase A2 activity and are recognized by the LDL scavenger receptor which is on the monocyte-macrophage membrane. The modified LDL are also immunogenic inducing formation of autoantibodies directed against them and normal LDL. Modified LDL and LDL immune complexes can be ingested by monocytes leading to foam cells and ROS. The damaged endothelial cells have an increased permeability to macromolecules, synthetize chemotactic factors, decrease their prostacyclin production and favour the adherence of neutrophils and monocytes to their surface. All these factors could increase ROS production and lipid peroxidation amplifying intra and extra-cellular accumulation of lipoperoxides in vascular walls. The ability of ROS and P to damage endothelial cells, to induce lipid peroxidation and thus to be involved in atherosclerosis relies on in vitro experimental results.(ABSTRACT TRUNCATED AT 250 WORDS)

It is well known that phenobarbital treatment increases the production of superoxide anion by liver microsomes. Since the toxicity of superoxide anion and of its product, hydrogen peroxide, is well documented we measured the activities of the liver enzymes which protect the cell against the reduced forms of oxygen and the microsomal content of lipoperoxides in phenobarbital-treated rats. It was found that no lipoperoxides accumulate in the microsomes and that glutathione peroxidase, glutathione reductase activities, and the peroxidative activity of cytochrome P-450 were increased while catalase and superoxide dismutase activities were not modified.

Rats were pretreated with various inducers of cytochrome P-450 before being exposed to pure normobaric oxygen (O2) in order to determine whether the inducers interfere with toxicity. The pulmonary and liver inducers beta-naphthoflavone (beta NF) and 3-methylcholanthrene (3MC) increased the survival rate and decreased the amount of pleural and lung fluid accumulation in adult rats exposed to oxygen. Phenobarbital (PB), which is essentially active in the hepatic microsomal cytochrome P-450, was less effective in counteracting oxygen toxicity. After 7 days of exposure to oxygen, none of the untreated rats survived, whereas 40, 73, and 90% survival was observed in rats treated with PB, 3MC, and beta NF, respectively. After 60 h of O2 exposure, significantly less pleural and lung fluid accumulation was observed in beta NF- and 3MC-treated rats than in untreated or PB-treated rats (p less than 0.001). Both beta NF and 3MC prevented the increase of lung peroxidation (assessed by measuring of malondialdehyde) and that of hydrogen peroxide production by lung microsomes induced by O2 exposure. These protective effects are associated with a large increase in the components of the pulmonary cytochrome P-450 system and its peroxidase activity and with an increased response to hyperoxia by lung antioxidant enzyme activities. In contrast, in control rats, the activities of the antioxidant enzymes were not increased, and both the quantity and the peroxidase activity of cytochrome P-450 were significantly decreased by O2 exposure. We conclude that in the rat, pretreatment by inducers of pulmonary cytochrome P-450 results in marked protection against O2 toxicity and an increase of antioxidant enzyme response to hyperoxia.(ABSTRACT TRUNCATED AT 250 WORDS)

Two unrelated Senegalese patients, both native of the Matam province, were found to have the same deficient G6PD variant. One has no hematological history, the other had several induced acute hemolytic episodes. The deficiency was almost complete in red blood cells and 20-30 percent of the normal level in leukocytes and platelets; in leukocytes the deficiency was due to a decrease in the molecular specific activity of the enzyme to which a molecular instability was added, explaining the greater deficiency in red blood cells. The electrophoretic mobility was slightly fast in leukocytes and platelets but normal in red blood cells. This pattern was confirmed by electrofocusing in ampholine-acrylamide gel. From a kinetic point of view, these enzymes were characterized by a lowered Km (G6P) (13 to 20 muM) a normal Km (NADP+), a Ki (NADPH) increased about twice, a thermal instability, a biphasic pH curve and an increased activation energy (15 kcal/mole). The polymorphonuclear cells were functionally strictly normal: engulfment, nitroblue tetrazolium (NBT) reduction test, induced iodination, and oxygen consumption were normal. The authors discuss the importance of post-synthetic modifications of the muted enzymes and their repercussions on the enzyme characteristics.

A patient presented with a posterior uveitis. An inferior plaque of retinal exudation was seen. Full investigation failed to establish a cause until six weeks later, when cryptococcal meningitis developed. The patient was immunocompetent. Exudation in relation to retinal vessels is unusual in idiopathic posterior uveitis, and cryptococcosis should be considered in the differential. Diagnosis is by lumbar puncture or vitreous aspiration.

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.

Whether or not cytochrome b-559 is a necessary component of NADPH oxidase activity in neutrophils is still controversial. In highly purified plasma membranes isolated from resting neutrophils and lacking cytochrome b, addition of arachidonic acid induced an NADPH oxidase activity. This activity was similar to that of plasma membranes isolated from phorbol myristate acetate (PMA)-stimulated cells which possessed cytochrome b. Addition of arachidonic acid to the latter plasma membranes did not alter the oxidase activity. It can be concluded that plasma membranes isolated from resting neutrophils have, in the presence of arachidonic acid, an NADPH oxidase activity similar to that of PMA-stimulated cells, except that it is independent of cytochrome b-559.