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L Prin

Publications and source records attributed to L Prin.

At least 55 records · Page 3Linked to original sources
PubMed1986

[Mechanisms of allergic asthma].

The patho-physiology of allergic asthma is the result of several closely interrelated mechanisms. The hypersensitivity to mediation by IgE implies mast cell intervention and also by other non-mast cells possessing a receptor for Fc fragments of IgE. Their activation leads to the liberation of numerous mediators, some of which act directly on the bronchial smooth muscle fibres whilst others intervene by "pro-inflammatory effects". The other essential compound of asthma is non specific bronchial hyperreactivity. In reality the two phenomena are closely linked as is shown with changes in bronchial hyperreactivity after exposure or the inverse, by elimination of the allergen. The slow reaction linked to IgE by the cellular influx which it provokes in the airways amplifies the local inflammatory reaction and by this interacts with the autonomic nervous system.

Adrenal Cortex Hormones↗
PubMed1986

Presence of factors chemotactic for granulocytes in hypereosinophilic syndrome sera: relation with alterations in eosinophil migration.

Recent work has underlined a structural and metabolic heterogeneity amongst blood eosinophils in various hypereosinophilic diseases. Little is known about the factors responsible for this variability. We have identified granulocyte chemotactic factors, termed GCFs in the sera of five patients with hypereosinophilic syndrome (HES). Sera from normal controls or from 20 patients with blood hypereosinophilia of various causes, but with little or no hypodense blood eosinophils, did not demonstrate any chemotactic activity. Two distinct GCFs were characterized, either by gel filtration or isoelectric focusing (molecular weights of 600 kD and 240 kD; pIs of approximately 5 and 7). These fractions are sensitive to proteolytic enzymes and to heating to 100 degrees C but not to 56 degrees C. The activity of GCFs has been tested towards neutrophils and eosinophils. The fractions of 240 kD and pI 7 appear more selective for the eosinophil lineage. Checkerboard analysis shows that such fractions are primarily chemotactic. In addition, hypodense eosinophils appear defective in random motility and chemotaxis towards chemotactic agents which are effective on normodense eosinophils. Moreover, preincubation of normodense eosinophils with HES sera rendered these cells unresponsive to very efficient chemotactic agents such as leukotriene B4 (LTB4) (decrease in migration of 91%; P less than 10(-3), formyl methionyl leucyl phenylalanyl (Fmlp) (decrease of 95%; P less than 10(-2)), HES sera (decrease of 91 to 93%). These findings suggest a process of deactivation of blood eosinophils with the possible retention within the circulation of activated hypodense eosinophils in HES.

Adolescent↗
PubMed1986

Eosinophilic lung disease: immunological studies of blood and alveolar eosinophils.

Five patients with eosinophilic lung diseases and blood hypereosinophilia (PIE syndrome) were investigated clinically and by bronchoalveolar lavage (BAL). Comparative studies on blood and alveolar eosinophils were carried out after purification and selection of eosinophil subpopulations according to their density. A predominant 'hypodense' alveolar eosinophil population was found in BAL fluids of active chronic eosinophilic pneumonia (CEP). In addition, supernatants of alveolar macrophages obtained from CEP are able to enhance spontaneously the generation of eosinophil oxygen metabolites. Such eosinophil stimulation emphasizes a probable tissue cell cooperation. In addition, BAL permitted the study of membrane immunological markers on eosinophilic inflammatory cells endowed with migratory properties. An increase in eosinophils carrying surface IgE was demonstrated in alveolar cells from PIE Syndrome particularly with hypodense eosinophils from CEP patients. Although no specific stimulus is known at the present time, this work underlines the potential implication of IgE-mediated hypersensitivity processes in the pathogenesis of eosinophilic lung diseases.

Adult↗
PubMed1985

Cytophilic IgE on human blood and tissue eosinophils.

Flow microfluorometry (FMF) was used to investigate the presence of cytophilic Ig (IgE or IgG) and the proportion of Fc receptor (Fc epsilon R or Fc gamma R)-bearing eosinophils among eosinophils from 21 hypereosinophilic patients. In 75% of the cases, it was possible to detect cytophilic IgE, significantly associated with serum IgE levels. Moreover, when lung and blood eosinophils were compared, the proportion of occupied Fc epsilon R was significantly increased on lung eosinophils, whereas very few cells had cytophilic IgG. This work provides further evidence that cytophilic IgE is not restricted to cells with high-affinity Fc epsilon R but can also be detected on the cell populations with low-affinity IgE receptors. These findings support the view that eosinophils can act as effector cells in immediate hypersensitivity reactions and in diseases associated with increased IgE production and hypereosinophilia.

Eosinophilia↗
PubMed1985

Cytophilic IgE on human blood and tissue eosinophils: detection by flow microfluorometry.

Flow microfluorometry (FMF) was used to investigate the presence of cytophilic Ig (IgE or IgG) and the proportion of Fc receptor (Fc epsilon R or Fc gamma R)-bearing eosinophils among eosinophils from 21 hypereosinophilic patients. In a large majority of the cases, it was possible to detect cytophilic IgE significantly associated with serum IgE levels. Moreover, when lung and blood eosinophils were compared, the proportion of occupied Fc epsilon R was significantly increased on lung eosinophils, whereas very few cells had cytophilic IgG. This work provides further evidence that cytophilic IgE is not restricted to cells with high affinity Fc epsilon R, but can also be detected on the cell populations with low affinity IgE receptors. These findings support the view that eosinophils can act as effector cells in immediate hypersensitivity reactions and in diseases associated with increased IgE production and hypereosinophilia.

Cell Separation↗
PubMed1985

[Brain stem infarction, systemic lupus erythematosus and circulating lupus anticoagulant].

A 30 year old man admitted with a brain stem infarct presented with intellectual deterioration. A diagnosis of systemic lupus erythematosus (S.L.E.) was based on the presence of five A.R.A. criteria :photosensitivity, arthralgia, leukopenia and thrombopenia, false positive syphilitic serology, antinuclear factors on immunofluorescence. A lupus type circulating anticoagulant (L.C.A.) was no longer detected after corticotherapy. This appears to be a case of the "hematologic" form of S.L.E. in which the presence of L.C.A. predisposes towards thrombosis, not only of veins--which is typical--but also of arteries. These may be isolated and reveal the underlying disease as in the present case. The L.C.A. is an antibody possessing antiphospholipid specificity which explains the anticoagulant action in vitro and the thrombogenic effect in vivo. Some authors consider this to be sufficient justification for administration of anticoagulants and/or antiplatelet agents, but corticotherapy may be effective.

Adult↗
PubMed1984

Secretion of a chemotactic factor for neutrophils and eosinophils by alveolar macrophages from asthmatic patients.

The studies presented in this article demonstrate the release of an IgE-dependent chemotactic factor for polymorphonuclear neutrophils (PMN) and eosinophils by alveolar macrophages (AMs) from normal subjects (n = 15) and allergic asthmatic patients (n = 15). A 60-minute incubation of normal AMs previously sensitized by 20% nonheated allergic sera with anti-human IgE antibody or the related allergen induced the release of a chemotactic activity (CA) for PMN and eosinophils in culture supernatants. When AMs were obtained from asthmatic patients, direct incubation with anti-IgE or the related allergen induced the same CA, whereas incubation with an unrelated allergen failed to produce CA (neutrophil CA after addition of anti-IgE, 22.5 +/- 3.5 cells per high power field; with related allergen, 15.8 +/- 3.6; with unrelated allergen, 0.7 +/- 1.8; p less than 0.0001). A partial characterization of the neutrophil chemotactic factor was carried out. Enzymatic treatment by trypsin or carboxypeptidase or by heating (56 degrees C for 3 hr) failed to abolish the neutrophil CA. After gel filtration the greater part of the neutrophil CA (80%) was recovered among low-molecular-weight components (300 to 1300 daltons). A preliminary deactivation of PMN by leukotriene B4 suppressed the CA of AM supernatants. These results indicate that IgE-dependent stimulation of AMs produces a neutrophil and eosinophil CA, present in a low-molecular-weight fraction possibly related to leukotrienes, and emphasizes the role of AMs in inflammatory lung processes during allergic asthma.

Adult↗
PubMed1984

[Multiple sclerosis and lupus].

At 20 year-old a patient developed a paraplegia which regressed within several months, suggestive of an acute myelitis. Subsequently, several episodes of spastic paraplegia, posterior tracts lesions and retrobulbar optic neuritis, a transient cerebellar syndrome, modifications in cerebrospinal fluid (pleiocytosis, hypergammaglobulin levels, elevated Delpech's ratio) suggested multiple sclerosis. When aged 62 years, the patient developed articular lesions, Raynaud's phenomenon, and buccal ulcers attributed to lupus. LE cells, native DNA anti-antibodies, anti-Sm auto antibodies on immunofluorescence were present. The possibility of a collagen disease, expressed initially and for a long period in an exclusively neurological disorder is discussed. It was considered, however, to be more likely two distinct affections. This association has been reported very rarely, even though two immunity-mediated inflammatory affections are involved.

Adult↗
PubMed1984

Role of IgE receptors in effector function of human eosinophils.

After analysis of the technical parameters of the rosette assay with human IgE-coated erythrocytes, Fc epsilon receptors for IgE (Fc epsilon R) on human peripheral blood eosinophils were compared to Fc epsilon R on lymphocytes and monocytes. Antibodies directed against Fc epsilon R on lymphocytes and monocytes inhibited the IgE rosettes formed by eosinophils from hypereosinophilic patients, which suggests that Fc epsilon R on eosinophils were antigenically related to Fc epsilon R on lymphocytes and monocytes. Fc epsilon R on human eosinophils were shown to participate in the killing effect of Schistosoma mansoni schistosomula in vitro in the presence of purified eosinophils from highly hypereosinophilic patients (blood counts greater than 3000/mm3) and anti-schistosomula IgE antibodies present in S. mansoni-infected patient sera. Similar levels of inhibition of cytotoxicity were obtained after preincubation of eosinophils with aggregated human IgE or with anti-Fc epsilon R antibodies, whereas preincubation with aggregated IgG or with anti-C3b receptor antibodies did not decrease the killing effect for schistosomula targets. This IgE-dependent cytotoxic capacity seemed restricted to eosinophils with an abnormally low density ("hypodense" cells) present only in highly hypereosinophilic patients. These observations might be related to nonparasitic situations in which increased levels of IgE and tissue or blood eosinophils are observed.

Antilymphocyte Serum↗
PubMed1984

Heterogeneity of human eosinophils. II. Variability of respiratory burst activity related to cell density.

Recent work has suggested that there may be heterogeneity amongst human eosinophils. In order to study this further, blood and tissue eosinophils were separated by density gradient centrifugation in discontinuous gradients of metrizamide. Blood eosinophils were obtained from 16 patients with blood eosinophil counts above 1 X 10(9)/l. Resident eosinophils were isolated from alveolar fluid in three of these patients and from pleural effusion in two others. A large proportion of the eosinophils in these patients were of light buoyant density (hypodense) and a high percentage of these showed morphological evidence of hypogranulation. Hypodense eosinophils had a reduced capacity to reduce nitroblue tetrazolium or develop chemiluminescence after stimulation with phorbol myristate acetate. It was concluded that there is structural and metabolic heterogeneity amongst blood and tissue eosinophils in patients with a variety of eosinophilic disorders.

Centrifugation, Density Gradient↗
PubMed1983

Heterogeneity of human peripheral blood eosinophils: variability in cell density and cytotoxic ability in relation to the level and the origin of hypereosinophilia.

Considerable variations in the distribution of eosinophil populations were revealed by density gradient centrifugation of peripheral blood leukocytes from 14 normal subjects and 31 patients with a transient or persistent hypereosinophilia. Such a purification procedure enabled us to collect in healthy controls, eosinophils (77.1 +/- 15.9% SD purity) with an appreciable cell recovery (21.7 +/- 14.0% SD) in the densest gradients ('normodense' cells). A high degree of purity was obtained in the same gradients, with leukocytes from patients with hypereosinophilia (84.4 +/- 11.9% SD pure eosinophils) but the cell recovery was significantly decreased (4.1 +/- 3.4% SD; p less than 0.001). A study of the various fractions found to contain eosinophils showed cells with an altered cellular density ('hypodense' cells) especially in marked hypereosinophilia. Furthermore, studies on leukocytes from patients with a very high hypereosinophilia (differential cell count greater than 70%) led to the recovery of almost pure fractions of eosinophils in the low density gradients. Functional studies were performed on each distinct cell fraction collected. They included investigations of their cytotoxic ability in a heterologous antibody-dependent cell-mediated cytotoxicity assay and their biochemical activity by using a previously described technique evaluating the membrane hexose transport. Variability in the functional potentialities was observed in relation to the cellular density: higher cytotoxic eosinophil abilities were noted in the case of the 'hypodense' cell population. According to biochemical criteria, these latter cells appear to be more activated and capable of responding to stimulation.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1983

[Effector functions of the polynuclear eosinophil].

The effector function of eosinophils is studied in experimental models, emphasizing the prominent role played by antibodies among which IgE, and also the activation of the cytotoxic activity by mast cell-derived ECF. A tetrapeptides. The demonstration of the cytolytic effect of basic proteins present in eosinophil granules allows to clarify this mechanism on a molecular basis. Eosinophil effector function is then envisaged in various clinical situations. In pulmonary eosinophilias, a relation appears between the detection of proteins released by eosinophils and the tissue damage. Eosinophils seem also to be implied in the inflammatory process characteristic of endomyocardial disease or in Crohn's disease. Whereas they were first considered as beneficial cells for the host, the eosinophil granulocytes may therefore express according to the targets, a dual either beneficial or nocious function.

Animals↗
PubMed1979

[Paravertebral hematopoietic pseudotumor during Paget's disease (author's transl)].

Extramedullary hematopoiesis is usually secondary to a severe and prolonged reduction in medullary functions, but can be the rare consequence of an extrusion of tissue formed of weakened or fractured bone. The hematopoietic nature of this pseudotumor can be confirmed histologically or, as in this case of Paget's disease, by Indium scintigraphy which can define the specific locations of the hematopoietic marrow.

Aged↗
PubMed1978

[Hyponatremia].

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Humans↗