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PubMed1985

Macrophages and infertility: enhancement of human macrophage-mediated sperm killing by antisperm antibodies.

The mechanism by which antisperm antibodies inhibit fertility is not completely understood. Macrophages may play a role in mediating infertility by interacting with sperm and destroying gametes. Experiments were conducted evaluating the effect of antisperm antibody on the phagocytosis and lysis of sperm by human peritoneal macrophages in vitro. Sperm from a fertile man treated with sera from normal men and women or medium alone had 5 to 280 molecules of IgG/sperm, as determined by a 125I-labeled anti-human IgG monoclonal antibody assay. By contrast, sperm treated with sera containing antisperm antibodies had 310 to 1240 molecules of IgG/sperm. Peritoneal macrophages harvested from infertile women with tubal/adhesive problems mediated phagocytosis and lysis of 111In-labeled sperm which was enhanced by treatment of the sperm with sera containing antisperm antibodies (39.0% +/- 1.5% versus 76.3% +/- 3.2% phagocytosis, and 3.3% +/- 0.3% versus 23.3% +/- 2.3% lysis of sperm [control versus antibody-treated]). The likelihood of fertilization in couples with antisperm antibody may be determined not only by the antibody but also by the presence of genital tract macrophages capable of destroying the antibody-coated sperm.

Agglutination Tests↗
PubMed1985

On the origin of peritoneal resident macrophages. I. DNA synthesis in mouse peritoneal resident macrophages.

Mouse resident macrophages were isolated from the unstimulated peritoneal cavity at various intervals after one intravenous injection of tritiated thymidine. EM autoradiography showed that 15 min after the injection, peritoneal resident macrophages, with the characteristic localization of the peroxidatic activity in the rough endoplasmic reticulum and the nuclear envelope, had already incorporated tritiated thymidine. In the peripheral blood, monocytes with silver grains over the nuclei were seen from 12 h onwards with a maximum at 48 h. In the peritoneal cavity labelled monocytes appeared at 24 h. The peak for labelled blood monocytes was not followed by a peak for labelled peritoneal resident macrophages. The conclusion is drawn that resident macrophages from the unstimulated peritoneal cavity are able to proliferate locally.

Animals↗
PubMed1985

On the origin of peritoneal resident macrophages. III. EM-immunocytochemical studies on the origin of mouse peritoneal resident macrophages.

The origin of resident macrophages was studied in chimera mice, F1(B10M X DBA2)----B10M, by means of EM-immunocytochemical detection of H-2 antigens on the cell surface of donor cells, F1(B10M X DBA2) (H-2d/H-2f haplotype), in the B10M (H-2f haplotype) host. The methodology used was an acceleration of the replacement of host peritoneal resident macrophages, reached by complete peritoneal cell depletion. In mice with successful engraftment of the bone marrow, the recovered peritoneal resident macrophage population showed the H-2d antigenic characteristics of the bone marrow donor. It was concluded that under the experimental conditions of this study peritoneal resident macrophages derive at least partly from precursor cells in the bone marrow.

Animals↗
PubMed1985

Macrophage interaction with skeletal muscle: a potential role of macrophages in determining the energy state of healing wounds.

A decrease in ATP and creatine phosphate (CP) is characteristic of local injury to skeletal muscle. Recent data have suggested adequate potential for high-energy phosphate production in the wounded tissue. Thus, an adequate explanation for the deficit in the high-energy tissue content in wounds was lacking. Since the wound has multiple components (muscle + cellular infiltrate), the tissue content represents the summation of these components. Therefore, a technique to separate these components was designed. Using a 0.5% solution of lambda-carrageenan as the wounding agent, the extensor digitorum longus muscles (EDL) of male Fisher rats were unilaterally wounded with intramuscular injections. Five days later, both wounded and contralateral nonwounded muscles were incubated in a standardized fashion. The groups of EDL were: wounded as described, contralateral nonwounded, or contralateral nonwounded with the addition to the incubate of 6 X 10(6)/ml lambda-carrageenan elicited peritoneal macrophages. Following incubation, the individual component parts of the system (muscle and macrophage) were rapidly frozen and assayed for high-energy phosphate and DNA content. Examination of the high-energy phosphate content of the separate components of a wound demonstrated that macrophages increased the ATP and CP content of normal skeletal muscle. Yet when total high-energy phosphate content was normalized for total DNA (muscle + macrophages) in the reconstituted system, the values approximated those of wounded muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1985

Effect of human colostrum and infant formula on the phagocytic activity of macrophages. I. Resident and stimulated mouse peritoneal macrophages.

Phagocytosis and degradation of radiolabelled human transferrin-anti-transferrin immune complexes by resident and stimulated mouse peritoneal macrophages was inhibited by liquid infant formula, particularly in the case of resident cells. Mouse peritoneal macrophages exposed to infant formula were shown by immunofluorescence to bind casein and beta-lactoglobulin, but there was little binding of alpha-lactalbumin. Comparison of various artificial milks, cow's milk and purified casein indicated that both the concentration and the degree of denaturation of casein may be important in the impairment of macrophage function by milk. It is suggested that bottle feeding of infants might result in impairment of macrophage function in the small intestine.

Animals↗
PubMed1979

Enhanced uptake of 3H-glucosamine by macrophages stimulated by macrophage-activating factor.

The enhanced uptake and incorporation of 3H-glucosamine by guinea pig peritoneal exudate macrophages stimulated by macrophage-activating factor (MAF) were studied. MAF was produced by concanavalin A- (Con A) stimulated lymphocytes. Two systems were developed to assay this phenomenon, one using microtiter plates, the other using suspension cultures. Enhanced uptake of 3H-glucosamine by macrophages was found after 48-hr incubation in microtiter plates and after 24 hr in suspension cultures. Increased uptake of 14C-glucose and 3H-galactose was also observed under these conditions. The enhanced uptake of 3H-glucosamine was markedly reduced or abolished by the addition of glucose to the cell cultures or by replacement of the medium with fresh medium before pulsing with labeled sugar. These observations indicate that the mechanism of enhanced uptake reflects in part increased glucose utilization by the stimulated macrophages.

Animals↗
PubMed1984

Activity of antileishmanial agents against amastigotes in human monocyte-derived macrophages and in mouse peritoneal macrophages.

Leishmania multiplying within either human monocyte-derived macrophages (HM) or mouse peritoneal exudate cells (PEC) have recently been shown to be susceptible to pentavalent antimony (Sb) by several investigators. The Sb susceptibilities of 5 cutaneous strains of Leishmania were compared in the 2 model systems, with infection of the macrophages initiated with either amastigotes or promastigotes. The susceptibility to Sb of amastigote-induced infections was statistically the same as the susceptibility of promastigote-induced infections for 4 strains in the PEC model, and for 3 of 4 strains in the HM model. Promastigote-induced infections with the 5th strain were non-viable in both macrophage types. The susceptibility of Leishmania to Sb within PEC was the same statistically as that of organisms within HM for amastigote-induced infections for 4 of 5 strains and for promastigote-induced infections by 3 of 4 strains. These data suggested that the susceptibilities of organisms to Sb within PEC and HM were generally comparable and that either amastigotes or viable promastigotes could be used to initiate the infection. The several technical advantages of the PEC model may make it more useful than the HM model for testing susceptibility to Sb. The modest susceptibility of some strains in both models to the peak serum amounts of antimony which may be achieved by presently recommended treatment regimes may partially explain the high current failure rate in simple cutaneous disease. The susceptibility of one strain within peritoneal cells to primaquine and WR 6026 (8-aminoquinolines), ketoconazole (an imidazole) and formycin B (an inosine analogue) was similar to that previously reported in human macrophages.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminoquinolines↗
PubMed1980

Alveolar macrophages. V. Comparative studies on the antigen presentation activity of guinea-pig and rat alveolar macrophages.

The addition of syngeneic alveolar macrophages (AM) to mitogen-stimulated lymphocyte cultures from the rat and the guinea-pig resulted in markedly dissimilar effects upon in vitro blastogenesis, guinea-pig AM stimulating the response and rat AM exhibiting strong suppressive activity. The capacity of guinea-pig and rat AM to initiate antigen-specific blastogenesis was also examined. Ovalbumin-immune lymph node cells from guinea-pigs were passed through nylon wool columns to deplete macrophages. This process abolished their capacity to respond to the antigen via blastogenesis. The addition of ovalbumin-pulsed AM to these cultures restored their blastogenic responsiveness, and did so with considerably greater efficiency than was observed employing peritoneal macrophages from the same animals. Identical manoeuvres in the rat again yielded opposite results; the addition of rat AM to syngeneic antigen-stimulated lymphoid cell cultures consistently suppressed blastogenesis, an effect not seen employing peritoneal macrophages from the same species.

Animals↗
PubMed1978

Macrophage Ia antigens. I. macrophage populations differ in their expression of Ia antigens.

By indirect immunofluorescence and microcytotoxicity it was demonstrated that different populations of murine macrophages bear different amounts of Ia antigens on their membranes. At least three subpopulations could be distinguished: those that lack Ia antigens and predominate in peritoneal exudate; cells bearing I-A antigens that are the majority of splenic macrophages and a minor population in the peritoneum; and cells bearing I-C antigens that are a minor population in both spleen and peritoneum. Internal radioisotope labeling studies confirmed that the I region molecules are synthesized by the macrophages. It is suggested that these different macrophage subpopulations may play distinct roles in the immune response.

Animals↗
PubMed1983

[Changes in the cAMP level in macrophages during the phagocytosis of Salmonella typhimurium. II. Effect of the virulence of microorganisms and the immune status of the macrophages on the dynamics of changes in cAMP levels].

The dynamics of changes in the level of intracellular cyclic AMP in nonimmune and immune macrophages in the process of the phagocytosis of S. typhimurium virulent strain, its heated variant and its mutant with low virulence was studied. A transient increase in the level of cyclic AMP was shown to occur during the first 30 minutes of phagocytosis; this increase did not depend on the kind of the phagocytized object and on the activity of macrophages and neither had it any influence on the outcome of phagocytosis. The virulent strain also induced the three-fold increase of the level of cyclic AMP in nonimmune macrophages prior to their disintegration caused by the cytopathogenic action of the microorganism. In immune macrophages the virulent strain did not induce the secondary increase of the level of cyclic AMP.

Animals↗
PubMed1984

Selective chemotaxis of Ia antigen-positive macrophages by macrophage chemotactic lymphokine produced by concanavalin A stimulation.

M1- cells (leukaemic cell line cells established from SL/Am mouse), Mm1 cells (macrophage-like cells subcloned from M1- cells), and undifferentiated B24 cells (subcloned from M1- cells) were similarly Ia-negative and showed little chemotactic response to macrophage chemotactic lymphokine (MCF-LD) produced by Con A stimulation of spleen cells. However, when M1- cells and B24 cells were differentiated by differentiating factor in the fibroblast-conditioned medium, they became positive for surface Ia antigens and exhibited chemotactic responses to MCF-LD. Treatment of the cell-line cells and mouse peritoneal exudate macrophages with anti-Ia antiserum and complement reduced the number of cells responsive to MCF-LD. Moreover, when comparing the chemotactic responses to MCF-LD of Ia-negative and Ia-positive peritoneal exudate macrophages, separated by electric programmable individual cell sorter (EPICS), Ia-positive cells responded more strongly than Ia-negative cells.

Animals↗
PubMedDate not supplied

A new approach to the biochemical mechanisms of macrophages: continuous human macrophage cell lines.

Macrophages are biologically complex cells that play a fundamental role in host defense from micro-organisms and tumor cells. Most of the biochemical mechanisms underlying their functions are still unknown. One of the macrophage functions that should be studied and understood at the molecular level is cytotoxicity toward tumor cells. Macrophage-like continuous cell lines of human origin cultured in vitro begin to be developed, and represent a new and possibly fruitful approach to the study of biochemical reactions at the basis of macrophage behaviour.

Cell Line↗
PubMed1982

Regulation of macrophage populations. IV. Modulation of Ia expression in bone marrow-derived macrophages.

The expression of I region-associated (Ia) antigens was studied in macrophages derived from bone marrow cell precursors cultured in L cell-conditioned medium (LCM) as a selective growth stimulator. Very few macrophages expressed Ia either while growing actively in LCM or when quiescent, after the removal of LCM from the culture. The addition of T cell lymphokines, however, stimulated the biosynthesis and membrane expression of Ia. Uptake of bacteria by the macrophage during exposure to the lymphokines produced a synergistic increase in Ia expression. The lymphokine-induced stimulation of Ia was reduced by the simultaneous presence of LCM, suggesting that growth and differentiative stimuli have opposing effects on Ia induction. All macrophage colonies derived from single precursors contained cells that could be induced to express Ia.

Animals↗
PubMed1978

Immuno-suppressive effect of human macrophages. II. Influence of macrophages on the kinetics of DNA, RNA and protein synthesis in PHA-stimulated lymphocytes.

Human macrophages obtained by culturing blood monocytes in vitro for 8 days release a soluble factor(s) inhibiting DNA synthesis and cell proliferation in PHA-stimulated lymphocytes. Synthesis of RNA and protein was strongly inhibited in PHA-stimulated lymphocytes sedimented on macrophages, as well as in lymphocytes separeted from the macrophages by a membrane, thus demomatrating that inhibition of RNA and protein synthesis was also mediated by a soluble factor(s). The kinetics of the factor-mediated inhibition showed that RNA synthesis was readily inhibited, whereas there was a delay in the inhibition of protein synthesis, thus indicating that the inhibition of protein synthesis and cell proliferation is a result of a blocking effect on the nucleic acid synthesis. The kinetics of DNA and protein synthesis in lymphocytes relieved from macrophage-mediated inhibition indicate a cytostatic effect.

Adult↗
PubMed1981

Alveolar macrophages. VI. Regulation of alveolar macrophage-mediated suppression of lymphocyte proliferation by a putative T cell.

Alveolar macrophages (AM) from normal rats suppressed antigen- or mitogen-stimulated blastogenic responses in cultures of splenic or lymph node lymphocytes, high levels of suppression often being observed when added AM comprised as few 0.6% of the total cells in culture. The efficiency of AM-mediated suppression of spleen cell blastogenesis declined with the age of the spleen cell donors, was severely curtailed by pretreatment of donors with low levels of cyclophosphamide, and was depleted by adult thymectomy coupled with thoracic duct drainage. The suppressive activity of AM was most obvious at high cell density, was unaffected by the presence of indomethacin in the cultures, or by prior X-irradiation of the spleen cells. Fractionation of spleen cells by velocity sedimentation yielded cell populations of greatly varying sensitivities to AM-mediated suppression, from small splenocytes (sedimentation velocity 1.1-2.8 mm/h) which were almost totally refractory to AM-suppression when assayed in isolation from the remainder of the spleen cell population, to larger cells (sedimentation velocity greater than 3.,5 mm/h) exhibiting high levels of sensitivity. Fractionation of spleen cells by glass wool adherence indicated decreased sensitivity to AM-suppression in the effluent population. Examination of the suppressive activity of individual subpopulations of AM separated by velocity sedimentation indicated that the larger macrophages were the most active in vitro. Suppressive activity of this nature was not seen with unstimulated peritoneal macrophages, but was observed when 'activated' peritoneal exudate cells were tested. These data are discussed in terms of a two-cell model for suppression of blastogenesis, the ultimate effector cell being a macrophage, the activity of which is controlled by a long-lived, recirculating lymphocyte, which we have provisionally designated as a T lymphocyte.

Aging↗
PubMed1982

Macrophages as effector cells of protective immunity in murine schistosomiasis. III. Loss of susceptibility to macrophage-mediated killing during maturation of S. mansoni schistosomula from the skin to the lung stage.

Newly transformed skin-stage and lung-stage schistosomula were compared in terms of their susceptibility to killing mediated by activated mouse macrophages in vitro. Although skin-stage schistosomula were readily killed by macrophages activated as a consequence of either BCG or Schistosoma mansoni infection and used either as cell monolayers or in suspension, lung-stage larvae appeared to be totally resistant to this effector mechanism and survived normally when reinjected into mice. Resistance of schistosomula to in vitro damage by macrophages was evident as early as 18 hr after host infection and was complete in worms recovered at 42 hr. The insusceptibility of lung-stage larvae is apparently not due to a defect in effector cell-target contact, because the induction of extensive macrophage adherence to the worms by the addition of anti-mouse red blood cell antisera to the cultures had no effect on parasite viability. These findings provide additional support for the concept that schistosomula during their development to the lung stage undergo a generalized change affecting their susceptibility to a variety of different immunologic effector mechanisms.

Aging↗
PubMed1980

Interaction between Pasteurella haemolytica and bovine alveolar macrophages: cytotoxic effect on macrophages and impaired phagocytosis.

Cultured bovine alveolar macrophages phagocytosed formalized 125I-labeled Pasteurella haemolytica organisms poorly when compared with uptake of an identical number of radiolabeled Yersinia enterocolitica organisms. The presence of immune serum enhanced uptake of P haemolytica, yet at high bacteria-to-macrophage ratios, a significant positive correlation existed between uptake and loss of cells from coverslips. This phenomenon was not observed with Y enterocolitica. While culture supernatant from P haemolytica either impaired phagocytosis or were cytotoxic to cultured macrophages, supernatant from Y enterocolitica did not show this effect. The observation of an apparent deterimental effect on bovine alveolar macrophages after uptake of P haemolytica may be used to explain events occurring in pneumonic pasteurellosis in cattle and may help in the development of immunizaiton techniques.

Animals↗
PubMed1994

Taxol induces the hematopoietic growth factor granulocyte-macrophage colony-stimulating factor in murine B-cells by stabilization of granulocyte-macrophage colony-stimulating factor nuclear RNA.

Taxol, a microtubule-stabilizing agent, has been shown to have antineoplastic activity against various tumors. In addition, it has been shown that taxol resembles bacterial lipopolysaccharide in its ability to activate macrophages. Recently we have shown that lipopolysaccharide induces the expression of the granulocyte-macrophage colony-stimulating factor (GM-CSF) in murine B-cell lines. In light of the similarity of taxol and lipopolysaccharide in their effects on macrophages, we tested whether taxol could also induce the expression of GM-CSF in B-cell lines. In the present study we used the murine B-lymphoma cell line M12.4.1. In unstimulated cells, no GM-CSF mRNA was detected, whereas in taxol-stimulated stimulated cells at a concentration of 30 microM, GM-CSF mRNA was induced 4-8 h after stimulation. This induction of GM-CSF mRNA was down-regulated by 10 ng/ml of interleukin 4. Actinomycin D chase experiments revealed that interleukin 4 did not affect the half-life of the taxol-induced GM-CSF cytoplasmic mRNA, nor did it alter GM-CSF gene transcription. Polymerase chain reaction analysis of nuclear RNA, utilizing probes specific for sequences in the first intron of GM-CSF, indicated that taxol enhances accumulation of nuclear precursor RNA and that interleukin 4 decreases this accumulation. The present study shows a novel activity of taxol in inducing the release of the hematopoietic growth factor GM-CSF from B-cells. Since GM-CSF is known to recruit macrophages and enhance their cytotoxicity against tumor cells, our observations suggest that part of the known antitumor activity of taxol may be due to synergistic effects of GM-CSF activity together with direct cytotoxic actions through microtubule stabilization.

Animals↗