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PubMed1975

Interaction of toxin of Corynebacterium diphtheriae with phagocytes from susceptible and resistant species.

The interaction of the toxin of Corynebacterium diphtheriae with leukocytes from sensitive and resistant animal species was examined by determining the ability of toxin to inhibit protein synthesis by several types of phagocytic cell. Small amounts of toxin (25 minimal lethal doses) impaired protein synthesis in both polymorphonuclear leukocytes and mononuclear cells from humans and guinea pigs, whereas large amounts (2,000 minimal lethal doses) were required for minimal inhibition of mouse phagocytes. Peritoneal macrophages from hyperimmunized guinea pigs exhibited the same high degree of sensitivity to diphtheria toxin as did those from unimmunized animals. Prolonged incubation with toxin resulted in a 75% reduction in phagocytosis of polystyrene latex spheres but had no effect on transport of the glucose analogue 2-deoxy-D-glucose by guinea pig macrophages. Thus phagocytic cells, although they are endowed with a high level of phagocytic cell appear to reflect the native resistance or sensitivity of the host species of origin.

Animals↗
PubMed1977

The morphology of echinoid phagocytes and mouse peritoneal macrophages during phagocytosis in vitro.

The morphology of mouse peritoneal macrophages and echinoid phagocytes during phagocytosis in vitro was studied. A striking similarity in the function of the foreign surface receptor is found in the two systems. Glutaraldehyde-treated erythrocytes attached randomly over the entire surface of the cells and were internalized without circumferential attachment between the particles and the phagocyte membrane. The particles seemed to sink directly into the cytoplasm of the cells. Tannin-treated erythrocytes were phagocytosed by the echinoid cells in a similar mode. The complement-coated erythrocytes were attached only in the perinuclear area of the echinoid phagocyte's membrane, but the morphology of their internalization was similar to that mediated by the foreign surface receptor. A circumferential attachment between the particles and the phagocyte membrane did not seem necessary. This is also the case for mouse peritoneal macrophages.

Animals↗
PubMed1977

An in vitro assay for the quantitation of phagocytic cells of different anatomic origin.

The survival of peritoneal exudate macrophages after 3 to 10 days in culture was examined by measuring the numbers of phagocytes per culture. This was determined by letting the cultured cells phagocytize Latex particles. The number of Latex particle-containing cells was taken as a measure of the survival of phagocytes. It was found that one tenth of the cells judged by light microscopy as macrophage-like survived the culture period. Thus, the calculated plating factor of 9.3 was used to estimate the actual number of macrophages in suspensions of spleen, lymph node or thymus cells by culturing these cells and subsequently counting Latex particle-containing cells. In addition, the acridine orange technique was used to determine actual numbers of macrophages in freshly prepared cell suspensions of lymphoid organs. Latex studies on spleen and thymus cells gave results correlating well with data obtained by the acridine orange technique. By contrast, many more acridine orange positive cells than phagocytizing cells were found when lymph node cells were cultured.

Animals↗
PubMed1976

Macrophage activity and clinical immunology. Origin and kinetics of mononuclear phagocytes.

The origin and kinetics of mononuclear phagocytes can only be studied after the cells have been properly characterized. The basis for such a characterization on morphological, cytochemical, functional, and immunological grounds has been discussed. The production and kinetics of mononuclear phagocytes during the normal steady state have been described and compared with the effect of an acute inflammatory stimulus on these parameters. The influence of hydrocortisone and azathioprine was also studied in this connection. The increased production and monocytosis seen during an acute inflammatory response have been shown to be regulated by a humoral factor. The concept of the mononuclear phagocyte system was also discussed and an outline of the participation of mononuclear phagocytes in pathological processes put forward.

Animals↗
PubMed1978

[Relationship between the phagocytic inhibition of the rat reticuloendothelial system and the anticholinesterasic effect of an insecticide, Carbaryl (author's transl)].

Phagocytic activity of the reticuloendothelial system (RES) and blood cholinesterase activity were determined in male rats after veinous administrations of carbaryl and 1-naphthol, a carbaryl metabolite. The various parameters were measured 1, 24, 48 and 72 hours after administration of the following four doses per 100 g body weight : 1.875, 3.75, 7.5 and 15 mumol. 1. Results showed an inhibition of the RES phagocytic activity (clearance of colloidal carbon) after carbaryl administration; although 1.875 mumol/100 g had no effect, the other doses inhibited RES activity, blockade time being a function of the dose given. The phagocytic function had returned to normal 72 hr after carbaryl administration. 2. Reductions in spleen weight and protein content were observed together with the RES blockade. 3. At all four doses, the anticholinesterase effect was already apparent one hour after carbaryl administration. 4. 1-naphthol, one of carbaryl's chief metabolites, had no effect either on the RES or on the different parameters studied. These results show a relationship between the phagocytic inhibition of the reticuloendothelial system and the anticholinesterasic effect by carbaryl. They suggest an inhibition of some esterases of macrophages interfering with the phagocytosis.

Animals↗
PubMed1978

Phagocytic activity of reticuloendothelial system of mice in shock-like state following administration of polysaccharide-protein complex isolated from Candida albicans.

Fever and shock are symptoms of acute disseminated candidiasis. Phagocytic activity of the reticuloendothelial system (RES), following a single administration of polysaccharide-protein complex, was studied with respect to the role of the RES in the pathophysiology of circulatory shock. The index of phagocytic activity was determined 15 or 120 minutes following IV administration of polysaccharide-protein complex (50 mg/kg) to mice, from the rates of clearance of carbon particles and of heterologous erythrocytes labeled with 51Cr. The mice were pretreated with hydrocortisone 300 mg/kg, methylprednisolone, 30 mg/kg, or saline 120 minutes before administration of the polysaccharide-protein complex. Depression of the phagocytic activity was observed following administration of polysaccharide-protein complex in both time intervals investigated. This depression could be prevented successfully by administration of both glucocorticoids studied. The fractional distribution of 86Rb was determined in other groups of identically treated mice. An increase of 86Rb uptake was found in the heart, lungs, and adrenals 15 minutes after administration of polysaccharide-protein complex. A decrease of 86Rb uptake was found in the intestines and spleen. These changes were also found in mice pretreated with glucocorticoids. A return to the normal picture of 86Rb fractional distribution was found 120 minutes after polysaccharide-protein administration. It was suggested that changes in phagocytic activity were not a result of altered hemodynamics.

Animals↗
PubMed1979

The role of M protein in phagocytosis. I. Activity of some enzymes in phagocytic cells during infection with Streptococcus pyogenes in vivo.

The phagocytosis of two type 12 Streptococcus pyogenes strains differing in M protein presence was investigated in vivo. The rate of phagocytosis and the streptococcal viability in phagocytic cells and outside of them was studied simultanously with estimation of enzymatic activity in phagocytic cells. It was observed that M positive strain was phagocytized at lower rate and also exhibited longer viability. Decrease of lactic dehydrogenase and ATP-ase activity in phagocytes of rabbits infected with M+ strain was also detected. These results suggest that M protein disturbs phagocytosis by inhibiting their main metabolic pathway of glycolysis.

Acid Phosphatase↗
PubMed1975

The structure of mononuclear phagocytes differentiating in vivo. II. The effect of Mycobacterium tuberculosis.

The development and resolution of granulomas induced by Mycobacterium tuberculosis were sequentially traced by correlated light and electron microscopy. The scattered, immature monocytes initially composing the lesions evolved by orderly steps into coalescent, well developed macrophages and ultimately into swirling nests of highly complex epithelioid cells. These ultrastructural changes represent differentiation in vivo of the mononuclear phagocytes. The number of mycobacteria present than waned markedly, and the epithelioid granulomas developed into foreign body granulomas and finally into simple chronic inflammation. Concmonitantly, the epithelioid cells evolved into macrophages and ultimately into immature, monocyte-like forms. These observations suggest that the development of a granuloma represents differntiation in vivo of the constituent mononuclear phagocytes in response to an evoking stimulus. From comparisons with previous studies, mononuclear differentiation in vivo appears to have a fixed pattern and a markedly alterable pace. The observations also suggest a previously undescribed fate for mononuclear phagocytes in developing granulomas. As the granuloma-evoking agent is destroyed, the highly differentiated mononuclear phagocytes change into less mature forms.

Animals↗
PubMed1978

Culture of mononuclear phagocytes on a teflon surface to prevent adherence.

A method is described for the culture of mononuclear phagocytes in suspension by incubation on a Teflon film to which the cells do not adhere. The characteristics of peritoneal macrophages, bone marrow mononuclear phagocytes, macrophage cell lines, and fibroblasts cultured in this way are similar to those observed after culture on glass or plastic surfaces. Culture of mononuclear phagocytes in Teflon film dishes has three important advantages: the cells can be easily harvested without damage, recovery is almost complete, and the cells are not functionally impaired. Thus, this method makes it possible to use cultured mononuclear phagocytes for many studied that could previously only be done in freshly collected cells.

Cell Adhesion↗
PubMed1976

Resistance of Neisseria gonorrhoeae grown in vivo to ingestion and digestion by phagocytes of human blood.

Attempts to study quantitatively the phagocytosis of gonococci from urethral pus failed because of the small numbers of organisms and technical difficulties. However, gonococci from chambers implanted subcutaneously in guinea pigs, which were similar to gonococci from urethral pus in their resistance to killing by human serum, were obtained in sufficient quantities for comparison in phagocytosis tests with the in vitro grown strains from which they were derived. Microscopic and viable counts of gonococci in phagocytes showed that in vivo grown organisms (strain BSV) were readily phagocytosed by human polymorphonuclear phagocytes. There was little difference betweee to ingestion. There was, however, a marked difference in the intracellular survival of strains BSV and BS during the first hour of phagocytosis. Whereas BSV organisms survived well, many BS organisms were killed. Subsequently, strain BSV and the survivors of the strain BS inoculum responded similarly to the intracellular bactericidins. These results were supported by electron microscopy of infected phagocytes. Resistance of gonococci in vivo to ingestion and digestion by human phagocytes seem to be important facets of the pathogenesis of gonorrhoea.

Humans↗
PubMed1976

Resistance of Neisseria gonorrhoeae to ingestion and digestion by phagocytes of human buffy coat.

In tests in vitro with the phagocytes of human buffy coat, a recent isolate of Neisseria gonorrhoeae, which was pilated, formed small colonies and resembled the virulent Kellogg type 2 (strain BS), resisted ingestion more than did another isolate (strain AL), which was non-pilated, formed large colonies and resembled the avirulent Kellogg type 4. Some members of both strains survived for significant periods within the phagocytes in test conditions that tended to minimise rather than maximise such survival; and strain BS had a greater capacity for intracellular survival than strain AL, with some of its members surviving for at least 8 h. Resistance to phagocytic ingestion is one important invasive mechanism of gonococci, and resistance to phagocytic digestion may also play a role in pathogenicity.

Cell Count↗
PubMed1977

Inhibitory effects of plasma from uraemic patients on human mononuclear phagocytes cultured in vitro.

Human mononuclear phagocytes were cultured in plasma from uraemic patients. The presence of uraemic plasma during the engulfment or digestion of 125I-labelled Candida albicans did not inhibit these functions in mononuclear phagocytes cultured for 8 days under normal condition. When normal human macrophages were cultured in the presence of uraemic plasma for 2-4 days, a marked detachment of the cells from the glass coverslips was registered. The phagocytic function of the remaining cells was impaired. Creatinine, urea and methylguanidine in concentrations higher than those usually measured in plasma from uraemic patients did not influence the functional properties of the cells. The inhibitory effect of uraemic plasma on the mononuclear phagocytes is suggested as an explanation for the increased frequency of infections in uraemic patients.

Candida albicans↗
PubMed1978

Cigarette smoke and phagocyte function: effect of chronic exposure in vivo and acute exposure in vitro.

Phagocytic function was studied in mice chronically exposed to cigarette smoke, and the effects of in vitro exposure to cigarette smoke on macrophage activity were also assessed. Cultures of radiolabeled Pseudomonas aeruginosa were employed to investigate phagocyte activity in vivo and in vitro. Mice were exposed on weekdays to fresh cigarette smoke for periods up to 37 weeks and the bactericidal and clearance activity of their lungs was measured. Both pulmonary clearance and bactericidal activity was impaired. The clearance of intravenously injected bacteria from the blood of smoke-exposed mice occurred at the same rate as in control mice, but the accumulation of radiolabel by the liver was decreased. In addition, the rate of elimination of radiolabel from the liver was less than the controls. Macrophages exposed to cigarette smoke in vitro initially had a depressed phagocytic rate, but if phagocytosis over a prolonged period was measured it was eventually enhanced over the rate of control macrophages. The vapor phase of cigarette smoke could also transiently inhibit and then enhance the phagocytic activity.

Animals↗
PubMed1979

Generation of hydroxyl radical by enzymes, chemicals, and human phagocytes in vitro. Detection with the anti-inflammatory agent, dimethyl sulfoxide.

Methane (CH(4)) production from the anti-inflammatory agent, dimethyl sulfoxide (DMSO), was used to measure .OH from chemical reactions or human phagocytes. Reactions producing .OH (xanthine/xanthine oxidase or Fe(++)/EDTA/H(2)O(2)) generated CH(4) from DMSO, whereas reactions yielding primarily O-(2) or H(2)O(2) failed to produce CH(4). Neutrophils (PMN), monocytes, and alveolar macrophages also produced CH(4) from DMSO. Mass spectroscopy using d(6)-DMSO showed formation of d(3)-CH(4) indicating that CH(4) was derived from DMSO. Methane generation by normal but not chronic granulomatous disease or heat-killed phagocytes increased after stimulation with opsonized zymosan particles or the chemical, phorbol myristate acetate. Methane production from DMSO increased as the number of stimulated PMN was increased and the kinetics of CH(4) production approximated other metabolic activities of stimulated PMN. Methane production from stimulated phagocytes and DMSO was markedly decreased by purportedly potent .OH scavengers (thiourea or tryptophane) and diminished to lesser degrees by weaker .OH scavengers (mannitol, ethanol, or sodium benzoate). Superoxide dismutase or catalase also decreased CH(4) production but urea, albumin, inactivated superoxide dismutase, or boiled catalase had no appreciable effect. The results suggest that the production of CH(4) from DMSO may reflect release of .OH from both chemical systems and phagocytic cells. Interaction of the nontoxic, highly permeable DMSO with .OH may explain the anti-inflammatory actions of DMSO and provide a useful measurement of .OH in vitro and in vivo.

Cells, Cultured↗
PubMed1977

Comparison of phagocytic and chemiluminescence response of human polymorphonuclear neutrophils.

The phagocytic activity and the chemiluminescence response of human polymorphonuclear neutrophils were studied with normal human serum used as opsonin for S. typhimurium and S. aureus. When serum was heated, chelated with ethyleneglycol tetraacetic acid (EGTA), or absorbed with zymosan, there were reduction of phagocytic activity for S. aureus and a comparable reduction of chemiluminescence; a 50 per cent decrease in phagocytosis by neutrophils corresponded to a 50 per cent reduction in the chemiluminescence response. In contrast, S. typhimurium was successfully phagocytized in serum treated with MgEGTA (complement--alternate pathway intact; classic pathway blocked), and chemiluminescence was reduced by only 20 per cent under the same conditions. Both neutrophil phagocytic and chemiluminescence responses for S. typhimurium were abolished when serum was heated at 56 degrees C. or adsorbed with zymosan. These findings suggest that both phagocytosis and chemiluminescence in neutrophils are interrelated, and the chemiluminescence response of neutrophils may be a reliable assay for measuring serum opsonic activity.

Egtazic Acid↗
PubMed1979

Phagocytic activity of rabbit pulmonary macrophages at different temperatures.

Phagocytic activity of pulmonary macrophages (PM) in contact with latex particles was studied in a group of twelve adult male rabbits, by means of in vitro phagocytosis tests at 35, 37, 39 and 41 degrees C. The phagocytic index at 35 degrees C was 14.70 (sigma = 4.5); at 37 degrees C, 19.61 (sigma = 4.7); at 39 degrees C, 22.45 (sigma = 5.1), and at 41 degrees C, 25.02 (sigma = 5.4). The value of the correlation coefficient between phagocytic index and temperature was r = 0.6022. The previous results allowed to conclude that there is lineal and direct relationship increase between phagocytic indexes and temperature.

Animals↗
PubMed1978

Use of lysostaphin to remove cell-adherent staphylococci during in vitro assays of phagocyte function.

Lysostaphin, a bacteriolytic enzyme, has been used to remove cell-adherent and extracellular Staphylococcus aureus from phagocyte-bacterial mixtures in vitro. Lysostaphin kills S. aureus more rapidly than penicillin, is not toxic for phagocytic cells and, when used for short periods at low concentrations, appears to enter neither human nor mouse mononuclear phagocytes. The use of lysostaphin provides the basis of a simple reliable direct in vitro assay for measuring the attachment and ingestion of S. aureus by phagocytic cells.

Bacteriolysis↗
PubMed1979

Role of phagocytic cells in host defence in relation to trauma--a brief review.

Present evidence available support a relationship between phagocytic cell function and survival from various types of trauma, e.g. burn, traumatic shock, and haemorrhage. Both polymorphonuclear phagocytes and mononuclear phagocytes (monocytes and macrophages) participating in the body's host defence are of crucial importance in preventing post-traumatic infections by microorganisms. The role of macrophages constituting the reticuloendothelial system (RES) in relation to trauma is paid special attention in this review. Deficit in a humoral opsonic glycoprotein (alpha 2 SB glycoprotein) important for reticuloendothelial phagocytosis is described in various types of traumatic injuries, and the role of RES in relation to pulmonary insufficiency is finally summarized.

Animals↗