Effect of anabol on the functional activity indices of mononuclear phagocytes

Anabol is a biopolymer from the complex of components extracted from the surface layer of the Lactobacillus bulgaricus cell wall. Its effect on certain indices of the functional activity of mononuclear phagocytes was studied. Administration of the preparation in a dose of 20 mg/kg 24 hours before the investigation resulted in lowering of the stain half-life in the general blood flow and increasing of the fibronectin levels in blood plasma of rats. Activation of the metabolic activity estimated by nitroblue tetrazolium test as well as resident cells and induced macrophages was observed. 24 hours after the anabol administration there was noted a marked increase in the pool of the precursors of granulocytes and macrophages, the stimulating effect being preserved for up to 3 days. The results showed that anabol had an effect on various elements of the system of mononuclear phagocytes. It may be useful in complex therapy aimed at increasing the host resistance to diverse toxic substances and bacterial infection.     

Transfer Agent of Immunity

An almost pure population of mononuclear phagocytes (macrophages) was obtained by repeated replacement of the culture medium. When treated in vitro with an immune ribonucleic acid (RNA) preparation extracted from the spleens of mice immunized with horse red blood cells (H-RBC), the rosette forming cells against H-RBC were demonstrated in some of the cultured macrophages but not against calf red blood cells. According to both microscopic observations and phagocytic activity, almost all of the rosette formers in this population were found to be large mononuclear phagocytes. These results support our view that large mononuclear phagocytes of mesenchymal origin constitute another cell line responsible for antibody formation in addition to the plasma and lymphocytic cell lines.     

Effect of myelopeptide-1 on the functional activity of phagocytes from mice treated with cyclophosphane

The capacity of the bone marrow-derived myelopeptide-1 (MP-1) to affect in vivo and in vitro the functional activity of phagocytes of intact mice and mice treated with a cytostatic agent (cyclophosphane) has been studied. It was found that MP-1 produces a correcting effect on the functional activity of bone marrow and peripheral blood phagocytes. An optimal scheme of the injection of MP-1 to mice with the cyclophosphane-induced immunodeficiency was developed, which provides a maximum immunocorrecting action. MP-1 had the most pronounced effect on the quantitative characteristics and the functional activity of phagocytes of different localization when introduced prior to the cytostatic; under these conditions, the pep tide affects peripheral blood neutrophils. The results obtained enable one to consider MP-1 as a preparation protecting the peripheral blood phagocytes from the damaging action of cyclophosphane.     

Use of liposomes to demonstrate the function of the mononuclear phagocyte system

The possibility of using liposomes containing an indicator composition (dye or fluorophor) for the determination of the eliminative activity of the system of mononuclear phagocytes (SMP) was studied. Liposomes were obtained by the sonication of the suspension of lecithin, cholesterol and an indicator substance. The rate of the elimination of liposomes from the blood stream after their intravenous injection into Wistar rats (males) was evaluated photometrically or fluorometrically in hemolyzed blood samples taken from the animals at different periods after the injection. The data thus obtained were processed by means of a microcomputer with the use of a specially developed program. The results of this investigation suggest that liposomes can be used for the study of the eliminative activity of SMP.     

Mechanisms of hemolysis under the effects of extreme factors

It has been shown that the activation of reno-dependence mechanisms of destruction of the low-stable population of erythrocytes was observed following the acute blood loss, the infusion of the phenylhydrazine and uranyl-glycerine solution. These mechanisms have different nature: humoral (increase of hemolytic activity of the blood serum up to 46.6%), autoimmune-cell or vasorenal (increase of the autoplateformation in 1.8 ones, of the activity of the system mononuclear phagocytes on 37.6%).     

Fate of intraperitoneally injected fluorescent microspheres in developing Ictalurus punctatus

Fluorescent microspheres (FMS) were injected intraperitoneally into channel catfish fry at 2 days post hatch (dph), 1, 2, 3, 4 and 8 weeks post hatch (wph). The FMS were observed in the vasculature almost immediately after injection in all age groups except 2 dph. Fluorescent microspheres were observed within mononuclear phagocytes in the vasculature after 0.16 dph in all age groups. Fluorescent microspheres were first phagocytized in the coelomic cavity immediately after injection, while the majority of coelomic FMS were phagocytized between 0.16 and 1 dph for all ages. Enzyme cytochemical staining indicated that both polymorphonuclear (neutrophilic granulocytes) and mononuclear phagocytes had phagocytized FMS in the coelomic cavity and organs, with a predominance of FMS found in mononuclear phagocytic cells in all age groups across all sample periods. The predominant organs associated with the observed cellular responses were the posterior kidney, spleen, and anterior kidney. Splenic organization and melanomacrophage development and activity were more pronounced as the fish aged from 2 wph on. Particulate clearance rates were faster in the 2 dph and 1 wph fish than the older ages of fish. These results suggest that to facilitate particulate retention, channel catfish should be vaccinated at 4 wph or older.     

Changes in the expression of the surface antigens of thymocytes during their cultivation with macrophages

The data on changes in expression of H-2 complex and Thy-1 antigens on cell surface of thymocytes resulting from their incubation with peritoneal macrophages has been presented. The process of joint cultivation of thymocytes with macrophages leads to significant decrease in number of cells with Thy-2-antigen and increase in that with H-2 complex antigens. An increase in H-2K+ cells in experimental thymocytes as compared to control ones was observed. No changes in H-2D expression was observed. A significant increase in Ia+ macrophages was observed after interaction with thymocytes as compared with intact mononuclear phagocytes.     

The effect of Mycoplasma arthritidis infection on the phagocytic activity of macrophages in rats and mice

The phagocytic activity of mononuclear phagocytes of A/J mice and Wistar rats was estimated by the carbon clearance test following injection of Mycoplasma arthritidis. In mice, the overall phagocytic activity was significantly increased at the end of the first week (P less than 0.0001), but the increase was marginal by the third and fourth weeks after injection. A significant increase in the relative weight of liver and spleen was observed even when phagocytic activity had returned to levels similar to those of controls (P less than 0.001). In rats, the overall phagocytic activity was significantly increased until the fourth week (P less than 0.00001). There was not, however, an increase in the relative weight of liver and spleen as observed for the mice. The results are discussed in the context of factors contributing to the pathogenic mechanisms responsible for differences in the patterns of arthritis due to mycoplasma observed in mice and rats.     

Characterization of mononuclear phagocytes in human CSF using membrane markers.

The purpose of this investigation was to demonstrate those membrane receptor sites on mononuclear phagocytes of human CSF which provide additional evidence for their monocytic origin and function. Using a heterologous system, sheep red blood cells were coated with IgG- and IgM-fraction of the anti-Forssman-antiserum of rabbits. In another series of experiments, sheep red blood cells were additionally sensitized with fresh human serum as a source of complement. The possible inhibitory effect of human IgG on the uptake of red cell antibody complexes was tested. Washed and pretreated sheep red cells were added to different fresh CSF specimens from patients, whose CSF exhibited no conspicious biochemical, serologic or cytologic alterations. The percentage of phagocytizing mononuclear phagocytes was evaluated. When the particular IgG EA reagent described was utilized, most of the mononuclear phagocytes consistently exhibited the IgG- and complement-receptor activity which selectively characterizes blood monocytes and related cells.     

Differential antimicrobial activity of human mononuclear phagocytes against the human biovars of Chlamydia trachomatis

The antimicrobial activities of human mononuclear phagocytes against Chlamydia trachomatis were investigated. Phagocytes cultured for 7 days or less were efficiently microbicidal. Almost complete inactivation of organisms from both human biovars was observed after 48 hr of incubation. However, organisms from the lymphogranuloma venereum (LGV) biovar survived in mononuclear phagocytes infected after 8 days or more in culture, whereas those from the trachoma biovar continued to be killed by such cells. Phagocytes cultured as long as 21 days killed the trachoma organisms with the same effectiveness as those cultured for 7 days or less. An ultrastructural study of inoculated phagocytes illustrated phagolysosomal fusion with degradation of organisms from either biovar in phagocytes which had been cultured for 24 hr before infection. Phagolysosomal fusion was not observed in cells which had been cultured for 8 days or more and then infected with LGV. The addition of interferon-gamma to these macrophages partially restored the phagocytes' microbicidal activity for LGV. Furthermore, a synergistic effect was observed when eosinophil peroxidase was added with interferon. Specific antibody failed to neutralize the infectivity of LGV organisms in 8-day or older mononuclear phagocytes. The findings may reflect the differences in disease syndromes between the two biovars, with the trachoma biovar causing more peripheral diseases and the LGV biovar causing a more systemic disease, with lymph node involvement as its main syndrome.     

Cytochemical localization of glucose-6-phosphatase in rabbit mononuclear phagocytes during differentiation

Cytochemical and biochemical investigations have revealed glucose-6-phosphatase (G-6-Pase) activity in Kupffer cells of the liver. To determine whether other mononuclear phagocytes are also reactive for G-6-Pase, rabbit bone marrow, blood, and alveolar macrophages were tested for G-6-Pase by a modified Wachstein-Meisel method and prepared for electron microscopy. Some mononuclear phagocytes from all three tissues were intensely reactive; others were unreactive. In promonocytes, monocytes, and alveolar macrophages, reaction product for the enzyme was localized throughout all cisternae of the endoplasmic reticulum (ER) and the perinuclear cisternae, but it was absent from the Golgi complex, lysosomes, and occasional smooth tubular channels. These results indicate that mononuclear phagocytes at all stages of development contain cytochemically demonstrable G-6-Pase and that the distribution of the enzyme is not altered during their differentiation from immature cells in the bone marrow to mature macrophages in the lung.     

The opsonizing activity of the sera of hamadryas baboons immunized with a preparation of the outer membranes of Francisella tularensis (based on data from the luminol-dependent luminescence method)]

The opsonizing properties of sera obtained from hamadryas baboons immunized with the preparation of F. tularensis outer membranes (OM) were studied with the use of luminol-dependent chemiluminescence (CL) of whole blood. The immunization of monkeys with the OM preparation was shown to lead to the formation of functionally active antibodies possessing opsonizing properties with respect to virulent F. tularensis. Immune sera obtained from the animals immunized with live vaccine and from those immunized with OM preparation had no essential differences in their opsonizing properties. The level of IgG antibodies in immune sera correlated with the CL parameters of whole blood in the presence of F. tularensis opsonized with these sera. Increased CL of phagocytes observed after addition of bacteria and immune sera under test to whole blood taken from a nonimmune donor made it possible to evaluate the functional activity of antibodies, thus permitting its use as a test for the evaluation of the effectiveness of new vaccine preparations.     

Functional Characteristics of Enhanced Fc Receptor Expression of β2 Integrin-Deficient Bovine Mononuclear Phagocytes

Fc receptor expression, cytoplasmic Ca²⁺ signaling, chemiluminescent (CL) response, and electron spin resonance (ESR) combined with spin trapping of blood mononuclear phagocytes from control heifers and a heifer with leukocyte adhesion deficiency (LAD) were evaluated to elucidate the relationships between complement receptor type 3 (CR3) and Fc receptor expression and their functional responses. The mean fluorescence intensity of fluorescein isothiocyanate (FITC)-conjugated anti-bovine IgG bound to mononuclear phagocytes from the heifer with LAD was 1.8-fold higher than that of control heifers. The mean increments of cytoplasmic Ca²⁺ concentrations of mononuclear phagocytes from the heifer with LAD stimulated with OPZ, Agg-IgG, and PMA were 39.4 (P<0.05), 118, and 71.6% compared with those of control heifers. A 1.27-fold increase in the CL response relative to control heifers was detected when mononuclear phagocytes from the heifer with LAD were stimulated with Agg-IgG. The OPZ-induced CL response of mononuclear phagocytes from the heifer with LAD was significantly (P<0.05) decreased, whereas the PMA-induced CL response was similar to that of control heifers. The ESR spectrum of mononuclear phagocytes from the heifer with LAD was increased when stimulated with Agg-IgG, and was impaired when stimulated by OPZ compared with that of control heifers. The ESR spectrum of mononuclear phagocytes stimulated with PMA was similar in control heifers and the heifer with LAD. Fc receptors on mononuclear phagocytes from the heifer with LAD were enhanced, and their cytoplasmic Ca²⁺ signaling, CL response, and ESR-spin trapping when stimulated with Agg-IgG and OPZ appeared to be associated with enhanced Fc receptors.     

Changes in the blood immunological indices of newborn infants as affected by T-activin in vitro

T-activin, introduced into the culture of mononuclear cells obtained from the blood of healthy newborn infants, does not induce any essential changes in the levels of E-, Ea- and EAC-rosette-forming cells. An overwhelming majority of healthy infants has shown a decrease in the functional activity of lymphocytes in the blast transformation test in response to the optimal dose of ConA and an increase in their functional activity in response to the suboptimal dose of this mitogen. After stimulation with phytohemagglutinin, both the increase of the stimulation index and its decrease have been observed in an equal number of cases. The introduction of the preparation into the culture of mononuclear blood cells isolated from newborn infants with sepsis leads to a considerable increase in the detection rate of Ea-rosette-forming cells with a tendency to an increase in that of E- and EAC-rosette-forming cells. The final values of the stimulation indexes, no matter what the mitogens used, are in conformity with the values characteristic of the normal parameters for healthy newborns, due to a specific pattern of changes in the T-lymphocyte functional activity in the blast-transformation test.     

The response of the mononuclear phagocyte system to chronic hyperglycemia

In this study we revealed a common reaction of cells of the mononuclear phagocyte system in the central and peripheral immunopoietic organs and pancreas in rats with chronic hyperglycemia. The activation of monocytopoiesis and recruitment of mononuclear phagocytes in peripheral tissues were observed. The modulation of the functional activity of mononuclear phagocytes by 3-aminophthal-hydrazide contributed to the normalization of monocytopoietic intensity and a decrease in the level of macrophagal infiltration in the thymus, pancreas, and peripancreatic lymph nodes. These changes indicate that mononuclear phagocytes are involved in the adaptive response to chronic hyperglycemia.     

Molecular Mechanisms of Regulation of Functional Activity of Mononuclear Phagocytes by Leptin

Leptin is a peptide hormone synthesized by adipocytes. The main function of leptin is associated with regulation of the body energetic balance and restriction of excess accumulation of fat. This review considers in detail the involvement of leptin in regulation of fundamental effector functions of mononuclear phagocytes, which express receptors for this hormone. Possible molecular mechanisms of modulation by leptin of phagocytic activity, oxygen-dependent microbicidity, and nitric oxide generation by mononuclear phagocytes are analyzed, as well as the role of leptin in the formation of the produced cytokine pattern. The data presented suggest that the regulation of mononuclear phagocytes by leptin is associated with activation of the JAK/STAT signaling pathway, which leads to stimulation of phagocytosis, production of oxygen and nitrogen reactive species, and also to increase in secretion of pro-inflammatory cytokines.__________Translated from Biokhimiya, Vol. 70, No. 8, 2005, pp. 1021–1029.Original Russian Text Copyright © 2005 by Shirshev, Orlova.     

Killing of Escherichia coli by mononuclear phagocytes and neutrophils stimulated in vitro with beta-1,3-D-polyglucose derivatives.

Human monocytes, human peritoneal macrophages, mouse peritoneal macrophages and human peripheral neutrophils pretreated with beta-1,3-D-polyglucose derivatives showed pronounced bactericidal capacity to Escherichia coli compared to control cells. The increased bactericidal capacity was detectable in mononuclear phagocytes over a wide range of concentrations of bacteria. Granulocytes, however, showed bactericidal capacity only at low concentrations of bacteria. The pretreated mononuclear phagocytes released significant amounts of IL-1 and PGE2. However, there was no significant release of tumor necrosis factor (TNF). By incubating unstimulated cells with purified IL-1 and TNF, the bactericidal activity of neutrophils and mononuclear phagocytes was enhanced. Our data indicate that the inability of neutrophils stimulated with beta-1,3-D-polyglucose derivatives to kill large numbers of bacteria could be overcome by a combined treatment with purified IL-1 or TNF in addition to beta-1,3-D-polyglucose derivatives. By incubating unstimulated cells with medium from beta-1,3-D-polyglucose-treated human peritoneal macrophages, the bactericidal activity of the cells was enhanced to the same extent as cells pretreated with purified TNF and IL-1. Cells incubated with IL-1-depleted medium from beta-1,3-D-polyglucose-treated human peritoneal macrophages, showed reduced bactericidal activity compared to cells incubated with undepleted medium. These studies demonstrate that beta-1,3-D-polyglucose-treated mononuclear phagocytes and neutrophils show enhanced bactericidal activity. The enhanced activity is partly caused by stimulation of the cells with IL-1 released from mononuclear phagocytes and partly by other unknown effects of beta-1,3-D-polyglucose derivatives on both mononuclear phagocytes and neutrophils.     

Effects of parathyroid hormone and calcitonin on adenylate cyclase in murine mononuclear phagocytes

Peritoneal mononuclear phagocytes elicited by thioglycollate demonstrate responsiveness to parathyroid hormone (PTH) and calcitonin (CT) which differs from that seen in the normal resident population. PTH causes a twofold stimulation of adenylate cyclase activity in elicited cells but inhibits this activity in resident cells. CT causes a greater stimulation of adenylate cyclase in elicited than in resident cells. Both CT and PTH cause an increase in cyclic AMP accumulation in cultures of elicited mononuclear phagocytes. These results indicate that cells of the mononuclear phagocyte lineage have functional receptors for both PTH and CT. This is the first biochemical evidence to support the hypothesis that mononuclear phagocytes are precursors of the bone resorbing osteoclast.     

Experimental Salmonellosis XI. Induction of Cellular Immunity and Formation of Antibody by Transfer Agent of Mouse Mononuclear Phagocytes

When mice were injected intraperitoneally with a ribonucleic acid (RNA) preparation extracted from the peritoneal mononuclear phagocytes (termed monocytes) of immunized mice, these macrophages developed cellular immunity and cellular antibodies. The peritoneal monocytes were obtained from normal mice and maintained in tissue culture bottles in a homogeneous cell population. When they were treated in vitro with an immune RNA preparation, they acquired cellular immunity, and cellular antibodies were detectable in such monocytes. These results suggest that the mononuclear phagocytic cell line constitutes a cell line responsible for antibody formation.     

Quantitative immunocytochemical characterization of mononuclear phagocytes. I. Monoblasts, promonocytes, monocytes, and peritoneal and alveolar macrophages

The purpose of the present study was to compare the phenotype of tissue macrophages with that of their precursors in the bone marrow and blood. The phenotype was determined on the basis of the quantitative binding of monoclonal antibodies to cell-surface antigens (antigen F4/80, complement receptor III, Fc receptor II, Ia antigen, common leukocyte antigen, and Mac-2 and Mac-3 antigens) on individual mononuclear phagocytes. Monoclonal antibody binding to cells, detected by the biotin-avidin immunoperoxidase procedure, was quantitated by cytophotometric determination of the amount of enzyme reaction product on cells. The results of this quantitation are expressed as the median of the specific absorbance per unit of cell-surface area (0.25 micron2) and per cell. Shortly after collection of the mononuclear phagocytes, binding of all monoclonal antibodies except those directed against the common leukocyte and Mac-2 antigens to peritoneal macrophages was enhanced compared with binding to blood monocytes; for alveolar macrophages we found reduced binding of monoclonal antibodies F4/80 and M1/70 (complement receptor III) and enhanced binding of monoclonal antibodies with specificity for the common leukocyte antigen and Mac-2 and Mac-3 antigens. The results obtained with cultured mononuclear phagocytes show that during the development from monoblast to tissue macrophages, monoclonal antibody binding to the various types of mononuclear phagocyte, expressed per unit of cell-surface area, was not significantly altered except that of M3/38 (Mac-2 antigen) to peritoneal macrophages and that of F4/80 and M1/70 (complement receptor III) to alveolar macrophages. Expressed on a per cell basis, the results show an increase in the binding of all monoclonal antibodies except those directed against the Fc receptor II and Mac-3 antigen during the development from promonocytes to peritoneal macrophages; binding of most monoclonal antibodies to alveolar macrophages was considerably lower than that to blood monocytes. It is concluded that the expression of the various cell-surface antigens alters during mononuclear phagocyte differentiation. The expression changed also during culture, although distinct patterns of alteration could not be distinguished.