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[The influence of cyclophosphane and phenthyrine and their combination with zymosan and serotonin on the functional features distingusihing peritoneal macrophages in mice].

Radiometric analysis into phagocytic activity of macrophages in intact and tumourous mice following introduction to them of phenthyrine and cyclophosphane showed the former to suppress to a greater extent the absorption function and the latter--that of digestion. A combined application of phenthyrine and cyclophosphane together with serotonin helps re-establish the microphages function in tumourous animals and to heighten the antineplastic activity of these compounds. Zymosan and its combination with phenthyrine and cyclophosphane do not produce any positive effect on the peritoneal cells.

Animals

Macrophage responses to mouldy hay dust, Micropolyspora faeni and zymosan, activators of complement by the alternative pathway.

Mouse peritoneal macrophages in culture exposed to mouldy hay dust, Micropolyspora faeni or glycopeptide or protein/glycoprotein fractions from this organism show marked biochemical changes. For comparison the interaction of cultured macrophages with zymosan has been investigated. All these agents induce the release of hydrolytic enzymes from macrophages, even in the absence of serum in the medium. The release is time- and dose-dependent and is not associated with loss of the cytoplasmic enzyme lactate dehydrogenase or any other sign of cell death. The parallelism between the capacity of these agents to activate the complement system via the alternative pathway and to induce inflammatory responses in vivo and selective lysosomal enzyme secretion from cultures of macrophages is discussed. The in vitro phenomena seen with mouldy hay dust, M. faeni, the protein/glycoprotein and the glycopeptide derived from it, may be relevant to understanding the role of mononuclear phagocytes in the disease farmer's lung and other inflammatory reactions.

Animals

Augmentation of antigen-stimulated histamine release from human basophils by serum-treated zymosan particles. II. Dependence on IgE-mediated release.

It was observed previously that serum-treated zymosan particles (Zx) augmented antigen and anti-IgE stimulated histamine release. With most of the enhancement attributed to an increased rate of release, this suggested that Zx was active only during the course of IgE-mediated release. This association between IgE-mediated histamine release and responsiveness to Zx was examined further in the present report. Addition of Zx at various time intervals after release had been initiated indicated that the basophil responsiveness to Zx was limited in duration; maximum responsiveness to Zx correlated closely with the period in which the rate of IgE-mediated histamine release was maximum. The time-dependent decline in sensitivity to Zx paralleled the kinetics for desensitization to antigen. Addition of Zx failed to cause release from basophils desensitized in vitro or from basophils of a donor who failed to release histamine upon challenge with anti-IgE. In contrast to the enhancement of IgE-mediated release, Zx did not augment histamine release caused by C5a or the synthetic peptide f-Met-Leu-Phe. It is concluded that an obligatory link exists between ongoing IgE-mediated histamine release and enhancement by Zx.

Antigens

[Effect of actinomycin D, carminomycin and bleomycin and their joint use with serotonin and zymosan on the functional state of the peritoneal macrophages].

The study of the effect of actinomycin D, karminomycin and bleomycin used alone or in combination with zimozan or serotonine on the functional state of the peritoneal macrophages showed that the use of the antibiotics in mice without tumors induced a decrease mainly in the absorptive capacity of the macrophages not changing significantly their digestive activity. The same antibiotics did not significantly change the initial low values of the functional activity of the cells in mice with transplantable tumors. The use of zimozan after completeness of the treatment course with actinomycin D, karminomycin and bleomycin in mice without tumors had a stimulating effect on the functional activity of the macrophages. Zimozan had a stimulating effect on the functional activity of the cells in mice with transplantable tumors only on its use after completeness of the treatment course with actinomycin D or bleomycin. Serotonine in combination with the above antibiotics had no stimulating effect on the functional activity of macrophages in mice both with and without tumors.

Animals

A properdin system intermediate formed by zymosan and serum at 0 degrees C.

The interaction of guinea pig or rat serum with Z at 0 degrees C leads to the formation of properdin pathway intermediate, ZPI, whose activity is assessed by its capacity to deplete the titer of cobra venom inducible lysis in diluted rat serum. The formation of ZPI does not require C1 or C2 and is not diminished by prior absorption of the serum with Z. In contrast, removal of P suppresses ZPI formation. Both Ca++ and Mg++ are essential cofactors for the formation of this intermediate whose function is abrogated in the presence of anti-C3, anti-P, but not by anti-Factor B. Since C4-deficient guinea pig serum is also effective in ZPI formation, the data suggest that ZPI is an alternative pathway intermediate containing both P and C3.

Animals

Regulation of prostaglandin synthesis and of the selective release of lysosomal hydrolases by mouse peritoneal macrophages.

Macrophages isolated from the peritoneal cavity of untreated mice and maintained in tissue culture synthesize and release prostaglandins when challenged with zymosan. These cells also selectively release lysosomal acid hydrolases under the same conditions. The major prostaglandins released into the media are found to be prostaglandins E1, E2 and 6-oxoprostaglandin F1a, whereas prostaglandin F2a is not detected. Macrophages isolated from mice that have received an intraperitoneal injection of thioglycollate broth are far less responsive to zymosan challenge. These cells require 300 microgram of zymosan to synthesize and release one-third the amount of prostaglandins released from non-stimulated macrophages exposed to 50 microgram of zymosan. In addition, thioglycollate-stimulated macrophages release less than 10% of their lysosomal acid hydrolases when exposed to 300 microgram of zymosan whereas non-stimulated cells release approximately 50% of these enzymes after treatment with 50 microgram of zymosan. The zymosan-stimulated synthesis and release of prostaglandins are completely inhibited by indomethacin, whereas the increased selective release of lysosomal acid hydrolases is not affected. Macrophages, unlike fibroblasts, do not synthesize and release prostaglandins when exposed to serum or to bradykinin.

Animals

Relationship of prostaglandin secretion by rabbit alveolar macrophages to phagocytosis and lysosomal enzyme release.

The phospholipids of rabbit alveolar macrophages were pulse-labelled with [(14)C]-arachidonic acid, and the subsequent release of labelled prostaglandins was measured. Resting macrophages released measurable amounts of arachidonic acid, the prostaglandins E(2), D(2) and F(2alpha) and 6-oxoprostaglandin F(1alpha). Phagocytosis of zymosan increased the release of arachidonic acid and prostaglandins to 2.5 times the control value. In contrast, phagocytosis of inert latex particles had no effect on prostaglandin release. Indomethacin inhibited the release of prostaglandin, and, at high doses (20mug/ml), increased arachidonic acid release. Analysis of the cellular lipids showed that after zymosan stimulation the proportion of label was decreased in phosphatidylcholine, but not in other phospholipids or neutral lipids. Cytochalasin B, at a dose of 2mug/ml, inhibited the phagocytosis induced by zymosan but increased prostaglandin synthesis to 3.4 times the control. These data suggest that the stimulation of prostaglandin synthesis by zymosan is not dependent on phagocytosis. Exposure to zymosan also resulted in the release of the lysosomal enzyme, acid phosphatase. Furthermore, cytochalasin B augmented the zymosan-stimulated release of acid phosphatase at the same dose that stimulated prostaglandin synthesis. However, indomethacin, at a dose that completely inhibited prostaglandin synthesis, failed to block the lysosomal enzyme release. Thus despite some parallels between the release of prostaglandins and lysosomal enzymes, endogenous prostaglandins do not appear to mediate the release of lysosomal enzymes. The prostaglandins released from the macrophages may function as humoral substances affecting other cells.

Acid Phosphatase