Inhibition of arachidonic acid release from human peripheral mononuclear cells by heat shock treatment and geldanamycin.

The objective of this study was to investigate the effects of heat shock (HS) treatment and geldanamycin (GA) on the release of arachidonic acid (AA) from human peripheral blood mononuclear cells (PBMC), monocytes and lymphocytes. Mononuclear cells prepared from blood of healthy subjects were preincubated with (3)H-AA. The release of (3)H-AA incorporated into the membrane was studied after pretreatment of cells by HS (43 degrees C, 1 h) and GA.

Age-dependent changes of K-elastin stimulated effector functions of human phagocytic cells: relevance for atherogenesis.

Effector functions of the elastin receptor on human phagocytic cells from young and older individuals were studied. In cells of young healthy subjects the elastin peptides, the agonists of receptor, stimulated both superoxide anion release from PMNs and phagocytosis of coated human red cells by monocytes. Elastin appeared to inhibit the cholesterol synthesis in monocytes, measured by the incorporation of 14C-acetate.

Insoluble glycogen, a metabolizable internal adsorbent, decreases the lethality of endotoxin shock in rats.

Insoluble glycogen is an enzymatically modified form of naturally occurring soluble glycogen with a great adsorbing capacity. It can be metabolized by phagocytes to glucose. In this study we used insoluble glycogen intravenously in the experimental endotoxin shock of rats.

Serum complement activation of SLE patients during plasmapheresis.

The erythrocyte complement receptor 1 (ECR1)-immune complex binding assay is a sensitive method for the determination of complement fragments which can be activated by bovine serum albumin (BSA)-anti-BSA in vitro. When the C3b/C4b containing bovine serum albumin (BSA)-anti-BSA was formed in the presence of the serum of patients with systemic lupus erythematosus (SLE) its binding to ECR1 was found to be lower than that formed in sera of normal volunteers. The plasmapheresis of SLE patients homozygous for the CR1/E high density allele displays a beneficial effect on the formation of C3b/C4b containing BSA-anti-BSA and its binding to ECR1.

The mechanism of inhibitory effect of eicosapentaenoic acid on phagocytic activity and chemotaxis of human neutrophil granulocytes.

Free eicosapentaenoic acid (EPA) was found to inhibit dose dependently the chemiluminescence of human neutrophil granulocytes phagocytosing zymosan and their chemotaxis induced by C5a-containing zymosan-activated serum (ZAS) and platelet-activating factor. Rigidification of plasma membranes in the ZAS-treated cells could be observed by measuring the fluorescence anisotropy. The cells were labeled by 3-[p-(6-phenyl-1,3,5-hexatrienoil) phenyl] propionic acid, reporting plasma membrane for determination of membrane fluidity.

Characteristics of stretch-release induced tension development in arterial smooth muscle.

Stretching helical strips of porcine a. carotis comm. to 1.

Candidacidal mechanisms in the human neonate. Impaired IFN-gamma activation of macrophages in newborn infants.

We studied the interaction between Candida albicans and mononuclear phagocytes derived from cord blood. In the presence of normal serum, the extent of phagocytosis and killing of candida by monocyte-derived macrophages was equivalent for newborns and adults. In the absence of serum both phagocytosis and killing by macrophages were reduced by half, but cord and adult cells were still equivalent.

Age-dependent alterations of human recombinant GM-CSF effects on human granulocytes.

The granulocyte-macrophage colony stimulating factor (GM-CSF) is an important in vivo regulator of granulopoiesis and neutrophil functions. It is well-known that the immune response and the transmembrane signalling in immune cells change with aging. We wished to elucidate the effects of GM-CSF in itself and in priming the activities of other inflammatory agents on neutrophils of elderly persons.

Transmembrane signaling changes with aging.

Altered immune response and transmembrane signaling with aging has previously been demonstrated. The aim of the present study was to characterize PMNLs and lymphocyte G proteins and to determine whether their relative amounts are altered with aging. First we studied the effects of FMLP on PMNLs IP3 formation.

Body composition in hypertensive elderly and middle-aged patients.

The occurrence of hypertension, leading to various life-threatening complications in the elderly is a widely recognized problem. The changes of body composition were determined in 120 control and untreated hypertensive subjects of various ages. In middle-aged hypertensive males, the total blood volume and plasma volume increased significantly compared to those of the healthy controls, while this increase was not significant in the case of hypertensive middle-aged females.

Effects of centrophenoxine on body composition and some biochemical parameters of demented elderly people as revealed in a double-blind clinical trial.

A double-blind clinical trial was performed on 50 persons (25 men, 25 women, average age 77 years) suffering from dementias of medium level (DSM III, Category 1, ICD No. 299). All subjects were residents in an old age home.

Altered phosphatidylinositol breakdown after K-elastin stimulation in PMNLs of elderly.

The degradation of elastic fibres during atherosclerotic plaque formation in arterial wall is a well known process. The liberated elastin peptides such as K-elastin possess various biological activities: They are chemotactic for monocytes and fibroblasts, stimulate the oxidative burst and the intracellular free Ca2+ mobilisation through the phosphatidylinositol (PIP2) breakdown in PMNLs. It was found that the PIP2 breakdown induced by K-elastin is a pertussis toxin sensitive process in PMNLs of young subjects.

Complement-mediated immune complex solubilization and precipitation inhibition in sera of patients with non-Hodgkin's lymphoma.

The complement functions of 42 patients with non-Hodgkin's lymphoma have been examined. The patients were divided into groups according to the severity of their disease: 1st--patients with high-grade lymphomas, 2nd--with low-grade lymphomas and 3rd--with chronic lymphocytic leukaemia. The adopted methods were the measurements of complement-mediated immune complex solubilizing capacity (CMSC) and the complement-mediated immune complex precipitation inhibition capacity (IPIC).

Age related impairment in phosphatidylinositol breakdown of polymorphonuclear granulocytes.

It is well known that with aging the immune response decreases. Most of the effector functions occur through specific receptors. Thus, we investigated the effects of various stimulants, acting through receptors or directly through the GTP-binding Gi protein, on phosphatidylinositol breakdown in PMNLs of young and elderly subjects and try to modulate it.

Immunobiological methods in the prenatal diagnosis and evaluation of foetal neural tube defects.

In cases of foetal neural tube defects (NTDs) macrophages are present in the amniotic fluid. These mononuclear cells were analysed with immunobiological methods: functional markers as Fc and C3b receptor-mediated phagocytosis and chemoluminescence have been studied. It was found that most of these pathognomic cells ingest haemolysin sensitized sheep red blood cells (sSRBCs) and zymosan (Mannozym) particles opsonized with fresh human serum.

Effects of herpesvirus infections on the chemiluminescence induced by zymosan phagocytosis in mouse peritoneal macrophages.

The chemiluminescence (CL) induced by zymosan phagocytosis was tested in mouse peritoneal macrophages infected with three different types of herpes viruses: herpes simplex type-1 (HSV-1), human cytomegalovirus (HCMV) and murine cytomegalovirus (MCMV). The intensity of CL was tested in various intervals of virus infections. In the first eight hours zymosan induced chemiluminescence decreased in all the three systems.

Defective immune complex degradation by monocytes in patients with systemic lupus erythematosus.

The binding of 125I-labelled anti-bovine serum albumin (BSA)-BSA immune complexes (IC), giving a final molar antibody to antigen ratio of 1:1, to monocytes isolated from 18 patients with systemic lupus erythematosus (SLE) and from 10 normal healthy donors was quantitatively investigated. The degradation of the bound IC by the same monocytes was kinetically determined at the same time. The assays were performed on monocyte monolayers.

Effect of mannozym on the chemiluminescence of phagocytes.

Mannozym (zymosan) induces chemiluminescence (CL) in human neutrophils, monocytes and in the cells of C4M phi murine macrophage cell line. The CL enhancing effect of Mannozym opsonized in human serum is higher than that of non-opsonized material. This may be due to the capacity of Mannozym to bind complement components and immunoglobulins from serum and to activate the phagocytes via their C3b and Fc receptors.

Effect of lentinan on the chemiluminescence produced by human neutrophils and the murine macrophage cell line C4M phi.

Lentinan, an immunopotentiating polysaccharide, stimulates the production of chemiluminescence (CL) by human neutrophils and the murine macrophage cell line C4M phi. The CL enhancing effect of lentinan opsonized in human serum is greater than that of lentinan itself. Lentinan's stimulation of neutrophil CL was increased by 1/2 when opsonized in human serum inactivated at 56 degrees C to remove complement, while the CL was increased two fold by lentinan opsonized in whole serum.

The effect of sera of patients with systemic lupus erythematosus on artificial immune complexes.

The solubilization of artificial immune complexes mediated by complements has been well-known since 1975. It is known that the process is bound to the integrity of the alternative complement pathway. The phenomenon of solubilization can be used in the investigation of the function of the complement system.

Body composition in elderly people. II. Comparison of measured and predicted body composition in healthy elderly subjects.

The predictive values of the equations of Moore et al. and Hume and Weyers and the measured values of body composition were compared in healthy, carefully selected aged and young subjects of both sexes. In the case of young subjects, these prediction equations seem to be adequate, even if this could not be affirmed with certainty by our results.

Body composition in elderly people. I. Determination of body composition by multiisotope method and the elimination kinetics of these isotopes in healthy elderly subjects.

The body composition of 40 healthy elderly and 20 healthy young subjects was determined and compared. It was found that the age-related changes were more marked in females than in males. Total body water was decreased as a consequence of diminished lean body mass.

Inhibition of anaphylaxis by inactivated lymphocyte clone with radiolabelled antigen.

125I-labelled ovalbumin (OVA) antigen did not sensitize guinea-pigs and anaphylaxis did not develop after native OVA challenge. The radiolabelled antigen was fixed by lymphocytes with highly specific receptors for 125I-OVA and this condition produced a continuous radiation damage leading to inactivation of the cells. As the proliferative response of lymphocytes did not occur, no antibody production was detected.

Effect of DTNB-treatment on Ca++-sensitivity of superprecipitation and ATPase activity of actomyosin.

A light chain of 18 000 daltons of native actomyosin isolated from rabbit skeletal muscle was removed by DTNB-treatment. Investigated were the differences in superprecipitation and ATPase activity of LC2-deficient and control actomyosin. The superprecipitation of control actomyosin develops in two phases, with high amplitude and kinetics dependent on the Ca++ concentration.

The effect of thrombin activated factor XIII, thrombin and plasmin on the chemiluminescence produced by human neutrophils stimulated by opsonized zymosan (Mannozym).

Coagulation factor XIII formed by thrombin activation from zymogen factor XIII decreases the chemiluminescence (CL) of human neutrophils stimulated by opsonized zymosan (Mannozym). At high concentrations, thrombin and plasmin also decreased the CL induced by opsonized zymosan. The inhibitory effect of all the three enzymes was due to their influence on the cell membrane receptors (C3b and Fe) and not to their direct effect on opsonized Mannozym.