bluuebunny/crossref_metadata_2025 huggingface dataset:
Soluble TNF and membrane TNF expressed on CD4+ T lymphocytes differ In their ability to activate macrophage antileishmanial defense
Authors: Birkland Timothy P , Sypek Joseph P , Wyler David J
Published: January 2018

In our studies of host defense against the intracellular parasite Leishmania major, we obtained evidence for a novel mechanism of macrophage activation for antimicrobial defense that involves direct cell contact between CD4+ T lymphocytes and Leishmania-infected macrophages. The mechanism is distinctive as it does not involve secretion of lymphokines but is apparently mediated by the membrane-anchored form of tumor necrosis factor (mTNF; ~50–60 kd) present on the surface of the effector T lymphocytes. Furthermore, it is not cytotoxic to the host cell and its expression is antigen specific and genetically restricted. We prepared a Leishmania-specific cloned T-T cell hybridoma line 1B6 (CD4+ TH1) that expresses membrane-bound TNF but does not secrete TNF or other macrophage activators. We now report that 1B6 cells can activate antileishmanial defense in inflammatory macrophages, whereas soluble recombinant murine TNF (sTNF) alone is unable to do so. On the other hand, both 1B6 cells and sTNF can act synergistically with recombinant murine interferon-γ (IFN-γ, a known soluble macrophage-activating factor) in activating antimicrobial defense and NO−2 release. The effects of 1B6 alone and the synergistic effects of 1B6 and IFN-γ or sTNF and IFN-γ are arginine dependent. These results suggest that mTNF may be more efficient than sTNF in macrophage activation and that contact with effector CD4+ lymphocytes that express mTNF may be an important mechanism of host defense.
Improved chemotactic ability of neonatal polymorphonuclear cells induced by mild membrane rigidification
Authors: Wolach Baruch , Dor Michal Ben , Chomsky Ofer , Gavrieli Ronit , Shinitzky Meir
Published: January 2018

Membrane lipid fluidity of peripheral blood polymorphonuclear cells (PMNs) of 24 newborn infants, 2–4 days after birth, was determined by steady-state fluorescence polarization with 1,6-diphenyl 1,3,5-hexatriene (DPH) as a probe and compared with that of PMNs from 23 adults. Measurements with intact cells, which correspond to all cellular lipid domains, did not display any statistically significant difference between PMNs of the two groups. However, application of bixinoyl glucosamine, a membrane-impermeable fluorescence quencher, revealed that the PMN plasma membrane of the newborn is about 23% more fluid than that of the adult. Total cholesterol-to-phospholipid ratio of newborn PMNs was found to be lower by about 10% than that of the adult, which could account for the difference in their plasma membrane fluidity. The possible implication of this finding for the deficit in chemotactic ability of leukocytes from newborns was tested with neonatal PMNs that have incorporated cholesteryl hemisuccinate (CHS), an efficient plasma membrane rigidifier. In all neonatal PMNs tested a mild incorporation of CHS (0.5–1 min incubation in 50 μg/ml dispersion) caused a significant improvement in their net chemotaxis, from an average value of 28 ± 7 to 43 ± 11. Longer incubations with CHS caused a gradual decrease in chemotactic ability that approached the basal level after about 5 min incubation. The net chemotaxis in adult PMNs was significantly higher than that of neonatal PMNs (72 ± 13) and was gradually inhibited by incorporation of CHS without any initial augmentation. Based on these results it was estimated that about 27% of the chemotactic deficit of neonatal PMNs is mediated by their immature fluid membrane.
In vivo prenatal chlordane exposure induces development of endogenous inflammatory macrophages
Authors: Theus Sue A , Lau Karen A , Tabor Dale R , Soderberg Lee SF , Barnett John B
Published: January 2018

Macrophages (m⊘s), important cells in host resistance, undergo a series of biochemical changes during their progression from the resident to the fully activated stage. Both resident and inflammatory m⊘s are characterized by some unique properties. In the present study, female BALB/c mice were prenatally treated with 8 mg/kg body weight of chlordane, a cyclodiene poly-chlorinated hydrocarbon that appears to reduce immunocompetence by selectively impairing m⊘ function. Therefore, we examined functions in m⊘s from chlordane-treated mice that had been stimulated with thioglycollate. The 5'-nucleotidase activity, present in high levels in resident m⊘s but low levels in inflammatory m⊘s was elevated in resident m⊘s from vehicle-exposed animals. Conversely, inflammatory m⊘s from these animals showed significantly diminished levels of this function. Moreover, chlordane-exposed m⊘s, regardless of whether they were resident or inflammatory, exhibited decreased 5'-nucleotidase responses. When a second function, transferrin receptor binding, was analyzed, vehicle-treated inflammatory m⊘s displayed high levels of activity whereas the resident m⊘s showed very little transferrin binding. However, both resident and inflammatory m⊘s from the chlordane-exposed group demonstrated transferrin binding activity similar in magnitude to that of the vehicle-treated inflammatory m⊘s. Finally, two-dimensional polyacrylamide gel electrophoresis analysis of m⊘s from chlordane-exposed mice have characteristics of normal m⊘s that have advanced to the inflammatory stage.
A Wave of elevated intracellular free calcium spreads through human neutrophils during phagocytosis of zymosan
Authors: Schwab J Conrad , Leong Denis A , Mandell Gerald L
Published: January 2018

The cytosolic concentration of free calcium ([Ca2+]i) plays an important role in the control of many neutrophil functions. In this study, we characterize the early rapid subcellular changes in [Ca2+]i that occur in adherent neutrophils during phagocytosis of zymosan particles, using both dual- and single-excitation wavelength Fura-2 ratio imaging. We observed a wave of elevated cytosolic calcium that began shortly after zymosan contact and propagated from the region of neutrophil contact with the zymosan throughout the cell at a rate of ≍ 17 μm/s at 31°. The wave was initiated by both opsonized and unopsonized zymosan and occurred independently of extracellular calcium. Multiple characteristics of the [Ca2+]i signal (including the absolute and regional [Ca2+]i and wave properties such as amplitude, frequency, duration, and topography) may be responsible for the differential regulation of cellular functions in the neutrophil.
Mycobacterial Infection Primes T Cells and Macrophages for Enhanced Recruitment of Neutrophils
Authors: Appelberg Rui
Published: January 2018

C57BL/6 mice intraperitoneally infected with Mycobacterium bovis BCG (substrain Pasteur) recruited significantly higher numbers of neutrophils after an intraperitoneal inoculation of either BCG protein antigen or of endotoxin than uninfected control mice. Antigen-induced neutrophil recruitment was mediated by T cells of both CD4+ and CD8+ phenotype and was also observed in the C5-deficient DBA/2 mouse strain. The adoptive transfer of immune serum did not prime mice for enhanced antigen-mediated recruitment of neutrophils. The endotoxin-mediated recruitment of neutrophils was also enhanced in infected as compared to uninfected DBA/2 mice. Finally, endotoxin-pulsed purified macrophages from infected C57BL/6 mice recruited higher numbers of neutrophils than endotoxin-pulsed macrophages from normal mice in an adoptive transfer to peritoneal cavities of naive recipient mice. These data show that during mycobacterial infection, T cells and macrophages are primed for recruitment of neutrophils after being triggered in specific or nonspecific ways. This may represent a means to cope with secondary infections by allowing for extensive neutrophil infiltration readily upon microbial challenge.
Subcellular localization of heparanase in human neutrophils
Authors: Matzner Yaacov , Vlodavsky Israel , Bar-Ner Matia , Lshai-Michaeli Rivka , Tauber Alfred I
Published: January 2018

Abstract The subcellular localization of a heparan sulfate degrading endoglycosidase, heparanase, was studied in human neutrophils. Unstimulated cells were disrupted by nitrogen cavitation and fractionated on a Percoll density gradient into three components, separating the plasma membranes, specific granules, and azurophilic granules. Heparanase activity was measured by gel filtration analysis of 35S-labeled degradation fragments released from subendothelial extracellular matrix (ECM) or produced during incubation with soluble, ECM-derived, heparane sulfate proteoglycans. Heparanase activity was found mainly in fractions containing the specific granules; this activity was inhibited by heparin. Freezing and thawing was not needed for recovery of the enzyme from the subcellular fraction, confirming previous data about its ready release. The mechanism of the ready release of heparanase from the specific granules requires further investigation.
Interstitial pulmonary macrophages produce platelet-derived growth factor that stimulates rat lung fibroblast proliferation in vitro
Authors: Brody Arnold R , Bonner James C , Overby Lila H , Badgett Annette , Kalter Valerie , Kumar Rakesh K , Bennett Richard A
Published: January 2018

Alveolar macrophages from humans and several animal species produce factors in vitro that modulate fibroblast growth and have been proposed as mediators of interstitial pulmonary fibrosis. Pulmonary interstitial macrophages (IMs) have not been studied previously in this regard. Pulmonary IMs were isolated from prelavaged rat lungs by enzymatic digestion of tissue and subsequent differential adherence of cells to culture dishes. The ability of IMs to release modulators of fibroblast growth into the culture medium was assessed by measuring [3H]thymidine incorporation into DNA and/or nuclear labeling of early-passage rat lung fibroblasts exposed to medium conditioned by IMs. The percentages of nuclei labeled in fibroblast cultures exposed to interstitial macrophage–conditioned medium (IMCM) alone did not significantly differ from that observed in controls, but fibroblasts exposed to IMCM supplemented with 2% platelet-poor plasma showed a 2.6-fold increase in labeling, indicating that IMCM contains predominantly “competence” growth factor activity. Similar results were obtained using purified human platelet-derived growth factor (PDGF). The level of growth factor activity released by IMs increased in cells that had phagocytized iron spheres during the culture period. In addition, fractionation of IMCM by high-performance liquid chromatography demonstrated most of the growth factor activity at a relative molecular mass of about 35 kd. Subsequent quantitative analysis of the fractions by an enzyme immunoassay for PDGF demonstrated that IMCM contains a homologue of human PDGF. These results show that IMs are capable of producing a PDGF-like growth factor for autologous fibroblasts and that release of this factor is enhanced by exposure to an insoluble inorganic particle. Because PDGF is a potent growth factor for fibroblasts and is released by IMs, it is essential to ask in future studies whether this or similar macrophage products play a significant role in mediating fibroblast proliferation in vivo.
Two populations of splenic dendritic cells detected with M342, a new monoclonal to an intracellular antigen of interdigitating dendritic cells and some B lymphocytes
Authors: Agger Ralf , Witmer-Pack Margit , Romani Nikolaus , Stossel Hella , Swiggard William J , Metlay Joshua P , Storozynsky Eugene , Freimuth Paul , Steinman Ralph M
Published: January 2018

A monoclonal has been isolated that labels an intracellular antigen in dendritic cells and some B cells. The M342 hamster immunoglobulin was selected because it stained cells in the periarterial sheaths of spleen, the deep cortex of lymph node, and the thymic medulla –- the same regions in which one finds interdigitating cells, the presumptive in situ counterparts of isolated lymphoid dendritic cells. M342 labeled an antigen within granules of isolated dendritic cells, but only in cells that had been cultured for a day and not in fresh isolates. This extends recent findings that most freshly isolated spleen dendritic cells are located in the periphery of the white pulp nodule and may serve as precursors for the periarterial pool of interdigitating cells, the site for M342 staining in situ. By electron microscopic immunolabeling, the M342 antigen was found exclusively in a type of multivesicular body. M342 staining was not found in mononuclear phagocytes from blood and peritoneal cavity. Peritoneal B cells expressed M342+ granules, and upon appropriate stimulation splenic B cells developed reactive granules as well. We conclude that M342 is a strong marker for interdigitating cells. Its existence reveals intracellular specializations in the vacuolar system of antigen-presenting cells including subsets of dendritic cells.
Interactions between HIV-infected monocytes and the extracellular matrix: increased capacity of HIV-infected monocytes to adhere to and spread on extracellular matrix associated with changes in extent of virus replication and cytopathic effects in infected cells
Authors: Dhawan Subhash , Vargo Maurann , Meltzer Monte S
Published: January 2018

Monocytes express cell surface receptors for extracellular matrix (ECM) proteins of basement membranes. These receptors are engaged during extravasation of cells through capillary endothelium into tissue. The number of human immunodeficiency virus (HIV)-infected monocytes that adhered to ECM over 2 h was threefold higher than that of uninfected control cells. This difference was ECM specific and was not observed with a bovine serum albumin substrate. Enhanced adhesion to ECM was evident in monocytes by 4 days after HIV infection and increased through 10 days. Monocytes exposed to a T cell–tropic HIV strain that binds to but does not replicate in monocytes showed no changes in adherence to ECM. Thus, productive infection of monocytes by HIV induces a significant increase in the capacity of these cells to interact with ECM. Enhanced adhesion of HIV-infected monocytes to ECM was associated with increased spreading: at 12 h, sixfold more HIV-infected monocytes were spread on ECM than were uninfected control cells. Cell processes of HIV-infected monocytes formed a complex network on ECM: many of these cells expressed HIV proteins as detected by indirect immunofluorescence. HIV-associated cytopathic effects and levels of virion-associated reverse transcriptase activity depended on the substrate to which monocytes were attached. Virus replication and cytopathic effects in monocytes adhered to ECM, fibronectin, or plastic alone were comparable. In contrast, HIV-infected monocytes attached to laminin showed a significant increase in virus replication and in extent of cytopathic effects through 2 weeks after infection. The lowest levels of HIV replication and cytopathic effects were in monocytes attached to collagen IV. Interactions between monocytes and ECM profoundly affect the manner in which these cells control HIV infection: HIV infection changes the capacity of infected monocytes to attach and spread on ECM; attachment to ECM alters the extent of virus replication in infected cells.
Type I interferons (IFN-α and -β) suppress cytotoxin (tumor necrosis factor-α and lymphotoxin) production by mitogen-stimulated human peripheral blood mononuclear cells
Authors: Abu-khabar Khalid S , Armstrong John A , Ho Monto
Published: January 2018

We studied the effect of the different types of interferons on the production of cytotoxin by human peripheral blood mononuclear cells (PBMCs) stimulated with the mitogen phytohemagglutinin (PHA). Maximum secreted levels of cytotoxin were observed at day 3 in culture and consisted of both tumor necrosis factor α (TNF-α) and lymphotoxin as determined by specific antibodies. Type I interferons (IFN-α and IFN-β) consistently suppressed cytotoxin production. Both TNF-α and lymphotoxin were significantly suppressed. Mean suppression by IFN-α and IFN-β (1000 U/ml) was 56 and 66%, respectively, in PBMCs from 18 different donors. The suppressive effects of IFN-α and IFN-β on cytotoxin production were dose responsive over a range of 10 to 1000 U/ml. Type II interferon (IFN-γ) did not have consistent significant effects. Pretreatment with IFN-α or IFN-β for 24 or 48 h prior to PHA stimulation also resulted in significant suppression. Supplementation with interleukin-2 (10 U/ml) or IFN-γ (1000 U/ml) did not overcome cytotoxin suppression by IFN-α or IFN-β. Cytotoxin suppression by IFN-α and IFN-β together appeared to be noninteractive. Suppression appeared not to be due to blockade of the cytotoxin release, since both cell-associated cytotoxin and secreted cytotoxin were suppressed to the same level. These results demonstrated that cytotoxin and lymphotoxin production by PHA-stimulated PBMCs could be down-regulated by type I interferons and that there is a substantial difference between the action of type I interferons and type II interferons (IFN-γ) in modulating the biosynthesis of cytotoxins.
Interactions between HIV-infected monocytes and the extracellular matrix: HIV-infected monocytes secrete neutral metalloproteases that degrade basement membrane protein matrices
Authors: Dhawan Subhash , Toro Luis A , Jones B Eric , Meltzer Monte S
Published: January 2018

The frequency of human immunodeficiency virus (HIV)-infected monocytes that spread on a model basement membrane was about twofold greater than that of an equal number of uninfected control cells through the initial 12 to 18 h of culture. By 24 h, virtually all HIV-infected and uninfected control cells spread on the basement membrane gel. The frequency of spread cells in the uninfected control population was < 10% of total cells by 12 days. In contrast, 30 to 40% of HIV-infected monocytes remained spread through this time interval and formed a dense interdigitated network of cell processes on and into the gel matrix. Invasion of the basement membrane matrix by HIV-infected monocytes suggested increased secretion of proteases able to digest the gel. Indeed, levels of neutral protease activity in culture fluids from HIV-infected monocytes were significantly higher than those from equal numbers of uninfected control cells. High levels of protease activity in culture fluids of HIV-infected monocytes required productive virus infection and were not observed with cells exposed to T cell-tropic HIV isolates. The predominant protease activity in these cultures was a 92-kd neutral metallogelatinase. HIV-induced changes in monocyte metalloprotease activity may be important for extravasation of infected cells to tissue or for the development of AIDS-associated neuropathology, carcinogenesis, and opportunistic infection.
Release of active oxygen radicals by leukocytes of Fanconi anemia patients
Authors: Korkina Ludmila G , Samochatova Elena V , Maschan Aleksei A , Suslova Tatjana B , Cheremisina Zinaida P , Afanas'ev Igor B
Published: January 2018

The release of oxygen radicals by blood and bone marrow leukocytes of patients with Fanconi anemia (FA) has been studied. It was found that the nonstimulated FA leukocytes and those stimulated by concanavalin A, SiO2, latex, and opsonized zymosan produced enhanced levels of luminol- and lucigenin-dependent chemiluminescence (CL) in comparison with normal leukocytes. At the same time, the ratio of the intensity of lucigenin-dependent CL to that of luminol-dependent CL was significantly smaller for FA leukocytes than for normal leukocytes. From these findings and from the effects of anti-oxidative enzymes and free radical scavengers on CL, it was concluded that FA leukocytes release enhanced amounts of oxygen radicals and that these free radicals contain enhanced amounts of hydroxyl or hydroxyl-like radicals more active than superoxide ion. It was proposed that elevated reactivity of the oxygen radicals released by FA leukocytes may be a major factor in the development of Fanconi anemia; this proposal is supported by the first positive results of treatment of FA patients with rutin (a nontoxic natural free radical scavenger and chelator).
Direct evidence for release of pore-forming protein during NK cellular lysis
Authors: Ortaldo John R , Winkler-Pickett Robin T , Nagashima Kunio , Yagita Hideo , Okumura Kb
Published: January 2018

In the present study, we have examined the exocytosis model for cellular lysis. Using monoclonal antibodies reactive with human pore-forming protein (PFP), we examined the localization of PFP at the interaction site of natural killer (NK) cells and the NK tumor targets K562 and Molt-4 as well as during antibody- dependent cellular cytotoxicity. Following the interaction of effector-target cell contact, an increased frequency of PFP was detected on the effector surface, in the micro- environment, and on the target surface of the interaction site. This temporal deposition of PFP was paralleled by loss of target cell integrity and release of chromium. In addition, selective deposition of PFP was seen at the interaction site of the target cell compared to other target cell regions. Collectively, these results are consistent with the exocytosis model and further support the hypothesis that PFP is one of the secreted moieties involved in NK cellular cytotoxicity
Transforming growth factor-β is the major mediator of natural suppressor cells derived from normal bone marrow
Authors: Moore Steven C , Shaw Michael A , Soderberg Lee S F
Published: January 2018

We previously reported that murine bone marrow cells activated by interleukin-3 (IL-3) or granu- locyte-macrophage colony-stimulating factor (GM-CSF) had potent nonspecific natural suppressor (NS) cell activity. In the present study, we demonstrated that these activated NS cells released a soluble factor (or factors) capable of nonspecifically inhibiting T cell mitogenic responses. Consistent with the properties of Transforming growth factor-β (7GF-β), treatment of the NS supernates with heat failed to denature the factor, and in fact significantly increased its suppressive activity. The NS suppressor factor strongly inhibited proliferation of the TGF- β-sensitive tumor cell line, A549. Cytokine activation of suppressive activity correlated with the production of a 10- to 13-kDa protein, consistent with the size of TGF-β and rIL-3 induced a sevenfold increase in TGF-β transcription. Finally, neutralizing anti-TGF-β antibody inhibited the suppressive activity of the supernates, indicating that TGF-β was responsible for most, if not all, of the suppression expressed by these bone marrow NS cells.
Induction of transforming growth factor-beta and prostaglandin E2 production by ethanol in human monocytes
Authors: Szabo Gyongyi , Verma Bikash K , Fogarasi Miklos , Catalano Donna E
Published: January 2018

To test our hypothesis that monocytes (MØ) and their mediators are major contributors to ethanol- related immunodepression, the modulating capacity of acute ethanol treatment was assessed on the production of transforming growth factor-beta (TGFβ) and prostaglandin E2 (PGE2) by human peripheral blood MØ. We demonstrate that acute in vitro treatment of adherent MO with either 50 or 150 mM ethanol induced a significant increase in the production of TGFβ (P < 0.045 and β < 0.001, respectively). Furthermore, MØ pretreatment with both 50 and 150 mM ethanol augmented TGFjS production in response to subsequent stimulation with the synthetic bacterial analog, muramyl dipeptide (MDP) (P < 0.05 and β < 0.001, respectively). Ethanol also increased TGFØ production in interferon β (IFNβ)- activated MØ in response to MDP stimulus (P < 0.05). MØ TGFβ levels, however, were always lower in IFNβ- activated than in non-IFNβ-activated MØ after the same stimulation with ethanol plus MDP, suggesting that MØ preactivation by IFN7 can partially counteract the TGFβ inducing potential of ethanol. Similar to its TGFβ - inducing potential, ethanol (150 mM) had the capacity to induce PGE2 production in adherent human MØ (P < 0.045). However, ethanol failed to augment MØ PGE2 production induced by the PGE2 secretagogue, MDP. TGFjS induction by ethanol was unaffected by the presence of cyclooxygenase inhibitor, suggesting that ethanol-induced MØ TGFß production does not require MØ PG£2 production. These results indicate that ethanol is a potent inducer for inhibitory MØ mediators, TGFjS and PGE2, and also has the capacity to augment MØ TGFß production in response to subsequent stimulation. Thus, ethanol-induced elevation of MØ TGFß and PGE2 production might contribute to decreased β cell proliferation and abnormal MØ functions after alcohol exposure, resulting in a depressed immune response.
Fibronectin cell-binding domain triggered transmembrane signal transduction in human monocytes
Authors: Chang Zong-Liang , Beezhold Donald H , Personius Christine D , Shen Zong-Lu
Published: January 2018

Fibronectin (Fn) fragments have recently been shown to stimulate tumor necrosis factor (TNF) secretion by human monocytes. In this study, we investigated the signal transduction mechanisms involved in Fn-induced TNF secretion. Treatment of human monocytes with Fnl20, a chymotryptic cell-binding fragment of plasma Fn, failed to cause a detectable rise in Ca2+ mobilization. Fnl20-induced TNF secretion could be inhibited with Ca2+ channel blockers. The protein kinase C (PKC) inhibitors H-7 and sphingosine inhibited the TNF-inducing activity of Fnl20. HA1004 was used as a control for the isoquinoline sulfonamide derivatives and did not change Fnl20-induced TNF secretion by monocytes. H-8 inhibited TNF secretion at higher concentrations. A calmodulin-dependent kinase inhibitor, W-7, was found to be effective, with 50% inhibition of Fnl20-induced TNF secretion at 5 μM. The activation and translocation of PKC were measured directly. In unstimulated monocytes, approximately 70% of PKC activity was found in the cytosol and 30% in the membrane. Following the stimulation of monocytes with phorbol myristate acetate (100 nM), rapid and sustained translocation of PKC from the cytosol to the membrane was observed. The stimulation of monocytes with Fnl20 triggered a rapid translocation of PKC within 2 to 5 min, followed by a return to normal levels within 8 min. These findings support the conclusion that Fnl20-induced TNF secretion requires the activation of PKC. J. Leukoc. Biol. 53: 79–85; 1993.
MRP-8 and MRP-14, two abundant Ca2+-binding proteins of neutrophils and monocytes
Authors: Hessian Paul A , Edgeworth Jonathan , Hogg Nancy
Published: January 2018

Two calrium-binding proteins, named migration inhibitory factor-related proteins-8 (MRP-8) and MRP-14, are primarily expressed by circulating human neutrophils and monocytes. Evidence accumulating from the investigations of several independent groups is now leading to an improved understanding of the biology of these proteins. Both MRP-8 and MRP-14 display features characteristic of members of the S100 family of calciumbinding proteins. Some of these features predict functions for MRP-8 and MRP-14 but to date an exact and well-defined function remains elusive. Here we review the available information and highlight evidence that suggests the function of MRP-8 and MRP-14 may be associated with both monocyte and neutrophil activation and the accumulation of these cells in inflammatory sites. J. Leukoc. Biol. 53: 197–204; 1993.
Inhibition of interleukin-1 release and activity by the rat seminal vesicle protein SV-IV
Authors: Vuotto Maria Luisa , Peluso Gianfranco , Mancino Domenico , Colonna Giovanni , Facchiano Antonio , Lelpo Maria Teresa , Ravagnan Giampietro , Metafora Salvatore
Published: January 2018

SV-IV, a 9.8-kd protein isolated from rat seminal vesicle secretion, has been shown to have strong non-species-specific immunosuppressive, anti-inflammatory, antithrombotic, and antiphospholipase A2 properties. The present investigation was undertaken to determine the mechanism of action of its immunosuppressive effects. It was found that SV-IV is a potent inhibitor of interleukin-1 (EL-1) release from lipopolysaccharide (LPS)-activated human adherent monocytes and an effective inhibitor of ILrl-induced thymocyte proliferation. The ability of SV-IV to form a noncovalent dimeric association with IL-1α but not with IL-1β, its ability to induce a marked decrease of IL-1 binding to its own receptors on the thymocyte surface, and its capacity to bind specifically to the macrophage plasma membrane might play an important role in the molecular mechanism of these inhibitory effects. J. Leukoc. Biol. 53: 214–222; 1993.
Aspergillus fumigatus antigen induced eosinophilia in mice is abrogated by anti-IL-5 antibody
Authors: Murali Pazhayannur S , Kumar Anoopa , Choi Hongyung , Bansal Naveen K , Fink Jordan N , Kurup Viswanath P
Published: January 2018

A murine model of allergic bronchopulmonary aspergillosis (ABPA), developed by exposure to Aspergillus fumigatus antigens, demonstrated eosinophilia of peripheral blood (PB), bone marrow (BM), and lung. The eosinophilia was abrogated by monoclonal anti-inter-leukin-5 (IL-5) antibody (TRFK-5) and not by an isotype control antibody (GL 113). Eosinophils in PB were enumerated from stained smears and their relative increase or decrease in cells from BM and lung was determined by an eosinophil peroxidase (EPO) assay (measured in optical density). Intraperitoneal injection of TRFK-5 in mice exposed to A. fumigatus antigen produced a significant reduction in eosinophils (PB 6.6 ± 1.14% vs. 3.8 ± 0.8%, P< .01) and EPO production in BM (0.935 ± 0.03 vs. 0.615 ± 0.02, P < .001). A similar reduction in EPO production in the lung (0.691 ± 0.12 vs. 0.495 ± 0.05, not significant) was also reflected in the histopathol-ogy for the different groups of mice. These findings confirming the role of IL-5 in eosinophilia, although not surprising, are significant in elucidating the immu-nopathogenesis of ABPA in the murine model. We conclude that in this model, eosinophilia may be due largely to the Th2 cytokine -IL-5 induced by A. fumigatus antigens. J. Leukoc. Biol. 53: 264–267; 1993.
Affinity purification and subcellular localization of kinesin in human neutrophils
Authors: Rothwell Stephen W , Deal Carolyn C , Pinto Jay , Wright Daniel G
Published: January 2018

Studies of granule-microtubule interactions in human neutrophils have suggested that mechanochemical ATPases such as kinesin or dynein may play a role in granule mobilization during neutrophil activation by inflammatory signals. In this study we show that proteins extracted from the surface of neutrophil granules, found previously to contain microtubule-dependent ATPase activity, caused microtubules polymerized from phospho- cellulose-purified rat brain tubulin to move across glass slides. Antibodies were generated against peptides based on two regions of the amino acid sequence of Drosophila kinesin: the ATPase active site (amino acids 86-99) in the head of the kinesin heavy chain and the tail of the heavy chain (residues 913-933). These antibodies were found to recognize kinesin in rat brain extracts as well as kinesin- like polypeptides in extracts of human neutrophils. Furthermore, when used in immunoaflmity chromatography, these antibodies permitted the isolation of a protein from neutrophil granule extracts that was recognized by Drosophila kinesin antibodies. Subcellular localization by immunofluorescence microscopy showed this protein to be associated principally with the cytoplasmic granules of neutrophils. J. Leukoc. Biol. 53: 372–380; 1993.
Functional alterations of human neutrophils by medium-chain triglyceride emulsions: evaluation of phagocytosis, bacterial killing, and oxidative activity
Authors: Bellinati-Pires R , Waitzberg DL , Salgado MM , Carneiro-Sampaio MMS
Published: January 2018

Medium-chain triglyceride (MCT) and long- chain triglyceride (LCT) emulsions currently used in nutritional therapy were evaluated for their in vitro effect on neutrophil oxidative metabolism, phagocytosis, and bacterial killing activities. Neutrophils from healthy adult male volunteers were assessed after blood incubation with commercially available fat emulsions containing LCT, MCT, or a mixture of 50% MCT and 50% LCT at a final triglyceride concentration of 20 mg/ml. It was observed that MCT-containing emulsions stimulated nitroblue tetrazolium (NBT) dye reduction by neutrophils as determined by a cytochemical NBT test performed directly on whole blood. This effect was dose dependent. However, after lipid removal by cell washing, the MCT-treated neutrophils showed decreased production of hydrogen peroxide (H2O2) and NBT reduction in response to bacterial lipopolysaccharide or phorbol my- ristate acetate stimuli as well as impaired phagocytosis and killing of Staphylococcus aureus. In contrast, the LCT emulsion did not alter any of the neutrophil functions evaluated. The present data suggest that MCTs elicit the oxidative metabolism of neutrophils, probably by phagocytosis of fat particles and, depending on the lipid concentration, this effect may not be reversible, leading to impairment of the cellular response to subsequent membrane stimuli. J. Leukoc. Biol. 53: 404–410; 1993.
Polyunsaturated fatty acids increase neutrophil adherence and integrin receptor expression
Authors: Bates Edna J , Ferrante Antonio , Harvey Dianne R , Poulos Alt
Published: January 2018

Fish oils are abundant in polyunsaturated fatty acids of the n-3 series (in particular eicosapen- taenoic, 20:5 and docosahexaenoic acid, 22:6). Such fatty acids are generally considered to be beneficial in the prevention of cardiac disease and to have anti-inflammatory properties. Neutrophil adherence is an essential early event in an acute inflammatory response, and we have demonstrated that both 20:5 and 22:6 stimulate adherence in vitro. Arachidonic acid (20:4, n-6) was also stimulatory. Significant stimulation of adherence was seen from 5 to 80 μM (nontoxic concentrations) 22:6, 20:5, or 20:4. At the lower fatty acid concentrations tested (≤40 μM) 20:5 was less active than 22:6 or 20:4 at stimulating adherence. Above 40 μM there was no difference in the ability of the three fatty acids to stimulate adherence. At the lower fatty acid concentrations tested (≤10 μM) 22:6 was less active than 20:4, whereas above 10 μM they were equally active. Immunofluorescent flow cytometric analysis of neutrophil integrin (adherence) receptors showed that the complement G3bi receptor (GDI lb) was up-regulated by these fatty acids. There was no change in GDI la or GDllc. Saturated fatty acids of the same chain length were without effect on adherence or receptor expression. The findings suggest that these polyunsaturated fatty acids may, under certain conditions, be proinflammatory with respect to their acute effects on the interaction of neutrophils with microbes, endothelium, and other tissues. J. Leukoc. Biol. 53: 420–426; 1993.
Reconstitution of recombinant N-formyl chemotactic peptide receptor with G protein
Authors: Schreiber Ronda E , Prossnitz Eric R , Ye Richard D , Cochrane Charles G , Jesaitis Algirdas J , Bokoch Gary M
Published: January 2018

A recombinant human neutrophil N-formyl peptide receptor (rFPR) expressed in transfected mouse fibroblasts (TX2 cells) was analyzed for its ability to couple physically with the heterotrimeric G protein, Gi. Im- munoprecipitation of photoaffinity-labeled rFPR and endogenous neutrophil formyl peptide receptor (nFPR) with an anti-FPR peptide antibody demonstrated that the receptors were identical in both size and extent of glycosylation. Coupling of rFPR with endogenous TX2 Gi was demonstrated by coimmunoprecipitation of the two proteins with an anti-Gi antibody. Moreover, rFPR was able to form a physical complex with purified Gi in a soluble reconstitution system. We observed similar affinities of rFPR and nFPR for Gi. This report provides the first direct evidence that rFPR associates physically with Gi and provides a foundation for analysis of the G protein coupling capacity of mutant rFPRs. J. Leukoc. Biol. 53: 470–474; 1993.
Interactions of lipopolysaccharide with neutrophils in blood via CD14
Authors: Weingarten Ronald , Sklar Larry A , Mathison John C , Omidi Shadi , Ainsworth Teresa , Simon Scott , Ulevitch Richard J , Tobias Peter S
Published: January 2018

The functional characteristics of neutrophils are exceedingly sensitive to physiological conditions as well as the details of isolation. Exposure to lipopolysaccharide (LPS) or even contamination of the isolating media with traces of LPS is known to play an important role in regulating cell function and expression of receptors. Because of the suspected role of GD14 as a receptor for LPS, we used anti-CD14 monoclonal antibodies both to identify CD14 in the cell surface of polymorphonuclear leukocytes and to inhibit functional changes elicited by LPS. Cytometric techniques were used to investigate the regulation of CD14 and CR3 on the neutrophil cell surface in whole blood to minimize any effects of isolation. In whole blood neutrophils express low levels of formyl peptide receptor, CD14, and CR3, which increase substantially in response to formyl peptide and LPS. The increases in CR3 and CD14 occurred in parallel and were independent of protein synthesis and tumor necrosis factor (TNF) production. The increase in CR3 was inhibited by antibodies MY4, 3C10, and 28C5 against CD14. These findings are consistent with the notion that in blood the observed receptor up-regulation is in direct response to the action of LPS on neutrophils through CD14 and does not require products from macrophages such as TNF or the production of C5a from the plasma. J. Leukoc. Biol. 53: 518–524; 1993.
An immunohistologic study of granulomatous inflammation in SIV-infected rhesus monkeys
Authors: Horvath Christopher J , Hunt Ronald D , Simon Meredith A , Sehgal Prabhat K , Ringler Douglas J
Published: January 2018

We studied granulomatous inflammation in simian AIDS using histologic, immunohistologic, and in situ hybridization techniques. Complete Freund’s adjuvant was used to induce granulomas in two control animals and two macaques infected with simian immunodeficiency virus (SIV) and having low peripheral CD4+ T cell counts. Control animals developed large (>2 cm diameter) epithelioid granulomas containing CD68+ macrophages (mφs), epithelioid mφs and multinucleated giant cells (MNGCs), CD4+ and CD8+ T cells, and small perivascular collections of CD20+ B cells. Lymphocytes rarely expressed proliferating cell nuclear antigen (Ki-67), and only rare endothelial cells expressed vascular cell adhesion molecule 1 (VCAM-1). In contrast, SIV+ animals had smaller (<0.5 cm diameter) epithelioid granulomas characterized by numerous large, dense CD8+, CD20+ lymphocyte aggregates with prominent local division (Ki-67+). Despite low blood CD4+ T cell numbers, there was a substantial CD4+ T cell infiltrate, accompanied by enhanced endothelial VCAM-1 expression. These granulomas contained no detectable SIV antigen or RNA. Thus, in simian AIDS, experimentally induced granulomatous responses are grossly attenuated, yet associated with increased local endothelial-leukocyte signaling and lymphocyte division. J. Leukoc. Biol. 53: 532–540; 1993.
Effects of macrophage-colony stimulating factor on human monocytes: Induction of expression of urokinase-type plasminogen activator, but not of secreted prostaglandin E2, interleukin-6, interleukin-1, or tumor necrosis factor-α
Authors: Hamilton John A , Whitty Genevieve A , Stanton Heather , Meager Anthony
Published: January 2018

It is often assumed that macrophage-colony stimulating factor (M-CSF) or CSF-1, as well as granulocyte macrophage-CSF (GM-CSF), can induce inflammatory mediator production by monocytes/macrophages. We demonstrate with elutriation-purified human monocytes that, in contrast to lipopolysaccharide, recombinant human CSF-1 does not induce secretion of prostaglandin E2, interleukin-6 (IL-6), IL-lβ, or tumor necrosis factor a, as measured by immunoassay; however, increased urokinase-type plasminogen activator (u-PA) activity in cell lysates and mRNA was observed. Similar results were obtained when the monocytes were treated with recombinant human GM-CSF. Such increased u-PA expression may contribute to the function of CSF-1 at sites of inflammation. J. Leukoc. Biol. 53: 707–714; 1993.
Coexpression of IL-2 receptor p55 and p75 by circulating blood lymphocytes
Authors: Sheldon A , Flego L , Zola H
Published: January 2018

By using high-sensitivity fluorescence and flow cytometry, it is possible to show that 30-40% of lymphocytes from PBL express the p55 chain of the IL-2 receptor, whereas the p75 chain is expressed at low concentrations on most lymphocytes without in vitro activation. The availability of a second fluorochrome capable of high sensitivity allows simultaneous analysis of p55 and p75, albeit with some sacrifice in sensitivity. Two-color analysis shows that a small proportion of cells (1-6%) coexpress measurable concentrations of both chains of the IL-2 receptor, and three-color studies show that these cells are predominantly CD4-positive T cells and express the CD45R0 isoform of the leucocyte-common antigen, i.e., have the phenotype of activated helper T cells. These cells may be a useful indicator of immune activation.
Isolation and confinement as a model for spaceflight Immune changes
Authors: Schmitt Didier A , Schaffar Laurence
Published: January 2018

The immune system of astronauts is disturbed during and after spaceflight. This situation may result from stressors encountered during the flight (microgravity, radiation, psychological stress, or confinement) or from physiological changes (demineralization or fluid shift). Therefore, ground-based investigations should be designed to determine the effects of these factors on the immune system. Very little is known about the influence of confinement or isolation on immune reactions. However, interesting data exist from experiments with animals and humans under different conditions (submarines, antarctic expeditions, single-person cave isolation, and underwater diving). The question remains as to whether these results can be extrapolated to spaceflight. Therefore, investigations of humans under isolation conditions analogous to space missions have been performed by Russian and, more recently, European investigators. Such investigations are important for understanding the physiological and psychological disturbances that occur during long periods of confinement, especially when future lunar and martian missions are considered.
Antiorthostatic suspension as a model for the effects of spaceflight on the immune system
Authors: Chapes Stephen K , Mastro Andrea M , Sonnenfeld Gerald , Berry Wallace D
Published: January 2018

We describe the use and appropriateness of antiorthostatic suspension in immunological investigations. This manuscript describes the model and discusses how well data obtained by using the model correlate with spaceflight data. This review concludes with some suggestions for future experiments using antiorthostatic suspension.
The effect of hypogravity and hypergravity on cells of the immune system
Authors: Cogoli Augusto
Published: January 2018

This article reviews the gravity effects discovered in T lymphocytes and other cells of the immune system. The strong depression of mitogenic activation first observed in an experiment conducted in Spacelab 1 in 1983 triggered several other investigations in space and on the ground in the clinostat and in the centrifuge in the past 10 years. During this period, great progress was made in our knowledge of the complex mechanism of T cell activation as well as the technology to analyze the lymphokines produced during stimulation. Nevertheless, several aspects of the steps leading to activation are not yet clear. Studies in hypogravity and hypergravity may contribute to answering some of the questions. A recent investigation in the U.S. Spacelab SLS-1, based on a new technology in which leukocytes are attached to microcarrier beads, showed that the strong inhibition of activation in microgravity is due to a malfunction of monocytes acting as accessory cells. In fact, interleukin-1 production is nearly nil in resuspended monocytes, whereas T cell activation is doubled in attached cells. In hypergravity, but not at lg, concanavalin A bound to erythrocytes activates B lymphocytes in addition to T cells. The activation of Jurkat cells is also severely impaired in space. These recent results have raised new questions that have to be answered in experiments to be conducted in space and on Earth in this decade. The experimental system, based on the mitogenic activation of T lymphocytes and accessory cells attached to microcarriers, offers an optimum model for studying basic biological mechanisms of the cell to assess the immunological fitness of humans in space and to test the feasibility of bioprocesses in space as well as on Earth.
Hapten-immune pulmonary interstitial fibrosis (HIPIF) in mice requires both CD4+ and CD8+ T lymphocytes
Authors: Hu Hui , Stein-Streilein Joan
Published: January 2018

We present a description and analysis of a mouse model for pulmonary interstitial fibrosis that is induced by a specific immune response to a small reactive chemical group called trinitrophenyl. We describe the model, and then we examine the cellular mechanism for the induction of the fibrosis. The specific increase in hydroxyproline reached a peak by day 7 and persisted through day 28 in all animals that were sensitized to and challenged with the hapten. Distinct patterns of fibrosis that were seen histologically correlated with antigenic pretreatment and were dependent on T lymphocytes. We also report that the inflammatory and fibrotic responses could be adoptively transferred with immune lymphocytes but not with immune serum. In vivo administration of anti-CD4 and anti-CD8 monoclonal antibodies to sensitized mice prevented the development of immune- mediated lung inflammation and was effective in reducing hydroxyproline deposition. We conclude that (activated) T lymphocytes contribute to the pathogenesis of pulmonary fibrotic diseases. The possibility arises that haptens in the environment may promote sensitization of individuals via their skin or lungs and cell-mediated immune responses to haptenated antigens within the lung may promote pulmonary fibrosis.