bluuebunny/crossref_metadata_2025 huggingface dataset:
Reticuloendothelial-Depressing Substance: Studies on the Mechanism of Action
Authors: Loegering Daniel J , Moon Dudley G , Kaplan John E , Weber Peter , Blumenstock Frank A
Published: January 2018

This study was carried out to evaluate the mechanism of action of a reticuloendothelial (RE)-depressing substance. This RE-depressing substance was obtained from the plasma of dogs subjected to 3 hr of intestinal ischemia. RE-depressing substance was partially purified by dialysis and reverse-phase column chromatography. The assay of RE-depressing activity was based on the depression of the rate of clearance of colloidal carbon from the blood of rats or mice. The effect of RE-depressing substance on three other RE system (RES) test particles (gelatinized lipid emulsion, formalinized sheep erythrocytes, and IgM-coated erythrocytes) was determined. RE-depressing substance did not affect the clearance rate or the organ localization of these three test particles. Therefore, RE-depressing substance affected only the clearance of colloidal carbon. Since platelet aggregation has been shown to contribute to the clearance of colloidal carbon, the effect of RE-depressing substance on platelet aggregation was evaluated. RE-depressing substance depressed in vitro platelet aggregation induced by ADP or collagen. It was concluded that the effect of RE-depressing substance on the clearance of colloidal carbon was due to a depression of platelet aggregation rather than to a depression of hepatic macrophage phagocytic function.
The Participation of Activated Peritoneal Macrophages in Treponema pallidum Subspecies pertenue Infection in Syrian Hamsters
Authors: Tabor Dale R , Azadegan Ali A , LeFrock Jack L
Published: January 2018

The role of cell-mediated immunity in hamsters during treponemal infection appears to involve the activated macrophage. To date, studies have been hindered by the inability to confirm that macrophages exhibit enhanced treponemicidal activity at the infection site. We show that lipopolysaccharide and thioglycollate-treated animals, when inoculated with Treponema pallidum subsp. pertenue, exhibit enhanced clearance of these organisms compared with controls. Macrophages from these infected groups display an enhanced respiratory burst, as detected by NBT reduction, as well as a marked increase in C3b receptor-mediated ingestion activity. Signficiant changes in these parameters indicate that alterations in macrophage activation are occurring in the infected compartment. Thus the stimulatory agents apparently modify the host's immune responses to promote subsequent reduction of treponemal infection. In addition, hamster peritoneal macrophages demonstrate enhanced activation behavior as a result of exposure to at least two signals, which may be prerequisite for processing this organism efficiently.
Identification of Plasma Cells in Lung Alveoli and Interstitial Tissues After Localized Lung Immunization
Authors: Bice David E , Gray Robert H , Evans Michael J , Muggenburg Bruce A
Published: January 2018

Large numbers of antibody-forming cells (AFC) can be identified with the Jerne plaque assay in immunized lung lobes of the beagle dog after localized instillation of particulate antigen. Published data suggest that these AFC are secreting antibody and are responsible for increased levels of specific antibody in immunized lung lobes. If AFC in the lung are actively secreting antibody, there should be an increase in the number of mature plasma cells in lung lobes exposed to antigen. The purposes of this study were to evaluate the number of lymphoid cells present in immunized and control lung lobes and to determine if lung immunization produces a localized increase in the number of plasma cells. Sheep red blood cells (SRBC), autologous dog red blood cells, and saline were instilled into specific lung lobes of beagle dogs with the aid of a fiberoptic bronchoscope. Light and transmission electron microscopy studies of tissues from lung lobes instilled with SRBC showed perivascular infiltrates and intra-alveolar accumulations of lymphoid cells which were not present in control lung lobes. The morphology of these lymphoid cells ranged from small lymphocytes through mature plasma cells. From 5% to 15% of the cells present in the interstitial tissues and alveoli of immunized lung lobes were plasma cells. These observations suggest that lymphoid cells which entered the SRBC immunized lung can mature to plasma cells which are probably responsible for the local production of antigen-specific antibody.
Differentiation of Rat Bone Marrow Cells Into Macrophages Under the Influence of Mouse L929 Cell Supernatant
Authors: Boltz-Nitulescu George , Wiltschke Christoph , Holzinger Christoph , Fellinger Alois , Scheiner Otto , Gessl Alois , Förster Othmar
Published: January 2018

Bone marrow cells (BMC) flushed from femora of Lewis rats were cultured in Dulbecco's modification of Eagle's medium supplemented with mouse L929 cell supernatant as a source of colony-stimulating factor (CSF). Differentiation of macrophage progenitor cells into macrophages (Mø) and expression of various markers were kinetically assessed. The proportion of Mø increases from approximately 4% in freshly isolated BMC to 100% after 7-8 days of cell culture. These cells, termed bone marrow cell-derived macrophages (BMDMø), adhere to and spread on plastic surface; exhibit Mø morphology; stain intensely for nonspecific esterase; are able to phagocytose latex particles, IgG-sensitized erythrocytes, and C3-coated red cells; and express receptors for IgG and C3. A subpopulation of BMDMø expresses MHC class II antigens as demonstrated by immunofluorescence using MRC OX6 and MRC OX17 monoclonal antibodies which recognize antigens coded in the I-A or I-E subregion of the MHC, respectively.

Collectively, our results show that supernatant from mouse L929 cells supports and is continuously required for proliferation and differentiation of rat BMC into typical Mø, and suggest that mouse CSF cross-reacts with the putative receptor on rat Mø.
Inhibition of Human Neutrophil Activation by the Allergic Mediator Release Inhibitor, CI-922: Differential Inhibition of Responses to a Variety of Stimuli
Authors: Wright Clifford D , Hoffman Michael D , Thueson David O , Conroy Mary Carol
Published: January 2018

The allergic mediator release inhibitor 3,7-dimethoxy-4-phenyl-N-1H-tetrazol-5-yl-4H-furo[3,2-b]indole-2-carboxamide, L-arginate (CI-922) is a potent inhibitor of human neutrophil functions in vitro. Over a concentration range from 1 to 100 μmol CI-922 inhibits the chemotactic response of neutrophils to the synthetic chemotaxin N-formyl-methionyl-leucyl-phenylalanine (FMLP). CI-922 also inhibits respiratory and secretory responses of neutrophils in response to agents that stimulate phospholipase C-dependent phosphoinositide hydrolysis to generate the second messengers inositol 1,4,5, trisphos-phate and 1,2 diacylglycerol, including: the plasma membrane receptor-specific ligands FMLP and C5a; serum-opsonized zymosan; concanavalin A; and the guanine nucleotide regulatory protein-specific stimulus guanosine-5′-0-(3-thiotriphosphate) (GTPγS). CI-922 also inhibits neutrophil functions stimulated by the calcium ionophore A23187. In contrast, CI-922 does not inhibit neutrophil responses to protein kinase C-specific stimuli such as phorbol 12-myristate 13-acetate (PMA) or L-α-1,2 dioctanoylglycerol (DiC8). CI-922 also fails to inhibit the synergistic activation of the respiratory burst by suboptimal concentrations of PMA and calcium ionophore A23187. The observation that CI-922 inhibits neutrophil responses to a variety of soluble and particulate stimuli, excluding protein kinase C-specific stimuli, allows us to postulate the site of action of the compound. We propose that CI-922 inhibits neutrophil activation at a site distal to signal transduction through the guanine nucleotide regulatory protein required for second messenger generation but proximal to phosphorylation reactions mediated by protein kinase C and calmodulin-dependent protein kinases.
Regulation of Macrophage-Derived Fibroblast Growth Factor Release by Arachidonate Metabolites
Authors: Phan Sem H , McGarry Bridget M , Loeffler Kathryn M , Kunkel Steven L
Published: January 2018

The macrophage is a source of many mediators with direct and indirect fibrogenic potential. In this study, release of macrophage-derived fibroblast growth factor (MDGF) activity by murine peritoneal macrophages is examined with regard to its regulation by arachidonate metabolites. Upon stimulation with 10 μg/ml lipopolysaccharide (LPS), resident peritoneal macrophages from CBA/J mice released MDGF activity into media rapidly, reaching maximal levels in approximately 1 h. Lysates of these stimulated cells also revealed significantly increased cell-associated MDGF activity, composing 45% of the total assayable activity. This activity, as assayed by radioactive thymidine incorporation by primary cultures of rat lung fibroblasts, was separable from interleukin-1 (IL-1) activity by reverse phase high performance liquid chromatography (HPLC). Furthermore, purified murine IL-1 had no MDGF activity in this assay system. This stimulated MDGF release was enhanced by the cylooxygenase inhibitors indomethacin, Ibuprofen, and aspirin at micromolar concentrations, but inhibited in a dose-dependent manner by prostaglandin E2 (PGE2). On the other hand, nordihydroguaiaretic acid (NDGA), a lipoxygenase inhibitor was inhibitory at 0.1 and 0.4 μM but not at 2.5 μM. Zymosan-stimulated macrophages also markedly increased MDGF release, albeit with a different time course which was characterized by a delay of approximately 7 h before peak levels were attained. Such stimulation, which is known to cause increased lipoxygenase activity, was also inhibited by 0.5 μM NDGA. In contrast, the lipoxygenase pathway products leukotrienes B4 (LTB4) and C4 (LTC4) stimulated MDGF release in a dose-dependent (10-10-10-8 M) manner, with LTC4 being more potent on a per unit dose basis. Stimulation by LTC4 was inhibited by the putative leukotriene receptor antagonist, FPL55712, while LTD4 and LTE4 did not stimulate MDGF release, thus suggesting the mediation of this effect by specific LTC4 receptors. These data suggest also that products of the cyclooxygenase and lipoxygenase pathways are potentially important both as exogenous (ie, derived from cells other than the macrophage itself) and auto- or self-regulators of macrophage MDGF release. This, in turn, implies that cyclooxygenase products are antifibrogenic and important in maintaining or returning to the quiescent or normal state, whereas the lipoxygenase products are profibrogenic and important in induction of fibrosis or wound-healing and tissue repair. Any alteration in the balance between these two pathways may result in either a desirable or a harmful outcome.
Effect of Mitogens on the Cell Cycle Progression and the Quantification of T-Lymphocyte Surface Markers in Acquired Immune Deficiency Syndrome
Authors: Hornicek F J , Malinin G I , Thornthwaite J T , Whiteside M E , MacLeod C L , Malinin T I
Published: January 2018

The cell cycle progression and viability of stimulated and intact lymphocytes from 20 subjects with acquired immune deficiency syndrome (AIDS) was determined by flow cytometry. As compared to controls, 62% less AIDS lymphocytes, cultured for 72 hr in the presence of lectins (Con-A, PHA, PWM), had entered the proliferative phases of the cell cycle, while the respective value for periodic-acid (H5lO6)-stimulated cells was 34%. The helper-suppressor ratios and natural kill cell percentages of the unstimulated and PHA-activated AIDS lymphocytes increased approximately 3-fold after 72 hr in culture. The natural killer (NK) cell fraction of the PHA-stimulated and unstimulated AIDS cultures comprised approximately 20% as compared to 10% in controls. However, no changes in the percentages of T-lymphocytes were detected in the AIDS cell cultures. Throughout the culture period, viability of the unstimulated AIDS lymphocytes exceeded 90%, whereas in stimulated cultures it fluctuated within the 65-90% range. It is concluded that the liability of AIDS lymphocytes to mitogens is probably a direct consequence of the human immunodeficiency virus (HIV) infection.
C3-Mediated Release of Prostaglandin From Human Monocytes: Evidence for Independent Regulation of Thromboxane and Prostaglandin Synthesis
Authors: Rutherford R Bruce
Published: January 2018

Human mononuclear phagocytes (HMP) lose the capacity to respond to C3b, exogenous arachidonic acid (AA), and other stimuli of arachidonic acid (AA) metabolism when precultured for 24 hours prior to the addition of stimulus. Data presented in this report suggest that this reduced capacity is not due to loss of the cyclooxygenase enzyme, to autoinactivation of cyclooxygenase, or to release by the cells of inhibitors of PGE and TxB2 production. Additional metabolism of PGE or a shift of AA metabolism from the cyclooxygenase pathway to the lipoxygenase pathways does not occur and hence cannot account for the observation. HMP precultured for 24 hours with gamma interferon (IFN-γ) retain the capacity to metabolize AA in response to subsequent exposure to C3b and LPS. HMP precultured with LPS or C3b respond to exogenous AA, but not to restimulation with LPS or C3b, by releasing PGE and to a lesser extent TxB2. The amounts of PGE and TxB2 produced under these conditions are reversed when compared to HMP treated with IFN-γ LPS, or C3b at the initiation of culture. These data suggest that the producton of TxB2 and PGE may be independently regulated in HMP and that IFN-γ affects HMP AA metabolism by different mechanisms than LPS or C3b.
Influence of Heparin and a Low Molecular Weight Heparin Fraction of the Leukocytes in an Experimental Venous Thrombosis Model
Authors: Doutremepuich C , Toulemonde F , de Seze O , Pereira F , Anne M C , Doutremepuich F
Published: January 2018

A randomized study was performed to observe the effects induced by heparin and a low molecular weight heparin fraction (at different dosages) on the leukocytes of rats in the presence of experimental venous thrombosis. The experimentation was carried out on two series of animals: the first with a ligature of the inferior vena cava inducing the formation of a thrombus, the second without any ligature. The results show that the induction of thrombosis involves: in the blood, an increase of the number leukocytes, principally polymorphonuclear cells; in the thrombi, a significant rise in the total count of leukocytes, here mononuclear cells; the latter number increases with the dosages of the administered drugs.
Expression of Ia Antigen in Colonies of Bone Marrow-Derived Macrophages
Authors: Yen Shing-Erh , Beelen Robert H J , Walker William S
Published: January 2018

Cells in colonies of culture-derived mouse and rat bone marrow macrophages were examined for membrane la antigen to determine if the steady-state expression of the antigen was restricted to macrophages derived from a distinct population of progenitor cells. Multiple subcultures of macrophages derived from single soft-agar colonies were tested for 1a + cells on three different days of culture. About one-half of the colonies gave rise to subcultures that never contained 1a + cells, about 40% yielded subcultures that contained some la+ cells on at least 2 of the 3 assay days, and about 10% of the colonies produced subcultures that contained 1a-bearing cells on all 3 assay days. Thus, when cultures were assayed at any one time for their content of 1a-bearing cells, the results raised the possibility of phenotypically distinct subpopulations of progenitors. However, sequential analyses of the subcultures revealed the variable expression of la on cells from at least one-half of the colonies. We conclude that, under steady-state conditions, the presence of la antigen on bone marrow-derived macrophages is not clonally restricted. That a T-cell-derived lymphokine induced la antigen on essentially all the cells in most of the colonies of macrophages confirms their potential to express the antigen.
Restoration of the Lipopolysaccharide-Responsive Phenotype in C3H/HeJ Peritoneal Macrophage-P388D1 Cell Hybrids
Authors: Zuckerman Steven H , Surprenant Yvonne M , Carlson Donald G , Beutler Bruce
Published: January 2018

The fusion of thioglycollate-elicited peritoneal macrophages from the lipopolysaccharide (LPS)-nonresponsive C3H/HeJ mouse strain to a hypoxanthine phosphoribosyltransferase (HPRT)-negative variant of the murine macrophage cell line P388D1 has resulted in the derivation of eight hybrid clones following HAT selection. Propidiumiodide staining followed by flow cytometry has demonstrated that the DNA content of the hybrids represents the sum of the parents. Codominant expression of class I antigens from both parental haplotypes is observed in the hybrids. While class II antigens are inducible following a 72-hr induction with gamma interferon-containing supernatants, the amount of each haplotype varies between clones. These hybrids demonstrate Fc-mediated crythrophagocytosis in contrast to P388D1. In distinction to the C3H/HeJ primary peritoneal-macrophage parent, LPS treatment of the hybrids results in the Increased release of both interieukin-1 (IL-1) and cachectin/tumor necrosis factor (TNF) into culture supernatants. Therefore, cell fusion has resulted in the stable restoration of the LPS-responsive phenotype in C3H/HeJ macrophage hybrids. These macrophage hybrids should serve as useful models In understanding the regulation of macrophage effector functions in response to environmental stimuli.
Tumor Cell Killing and Cytostasis by C3H/HeJ Macrophages Activated In Vitro by Lipid A-Associated Protein and Interferon Gamma
Authors: Chapes Stephen K , Killion James W , Morrison David C
Published: January 2018

Experiments have been carried out to assess the ability of purified protein-free lipopolysaccharide (LPS) and lipid A-associated protein (LAP) containing LPS to activate macrophages from C3H/HeJ endotoxin-unresponsive mice. Assays for in vitro activation have included cytotoxic and cytostatic effects on a simian virus 40 (SV40)- transformed fibroblast cell line. While neither preparation of LPS would effect C3H/HeJ macrophage activation for either cytostasis or cytolysis, the addition of murine interferon gamma to cultures of LAP-LPS stimulated C3H/HeJ macrophages resulted in cells which were both cytotoxic and cytostatic. These results suggest that LAP can provide one component of the triggering mechanism but, of itself, is insufficient to effect full activation. A second signal, which can be provided by murine interferon gamma, appears also to be required.
Human Natural Killer Cells Enhance a Mixed Leukocyte Reaction
Authors: Weissler Jonathan C , Yarbrough William C , Toews Galen B , Nicod Laurent P
Published: January 2018

Natural killer cells (NK) have been reported to down-regulate the initiation of T cell responses in animal models. In the current study, highly purified CD16 + human NK cells were obtained by cell sorting and their effect on the stimulation of allogeneic T cells (MLR) determined. NK cells did not directly stimulate T cell proliferation. However, when added to a population of loosely adherent mononuclear cells (LAM), NK enhanced the ability of these accessory cells to stimulate T proliferation. This effect was not reproduced by the addition of sorted CD5 + T cells, sorted CD16 – cells, or control lymphocytes to the MLR. The effect of NK on the MLR was not restricted by class II antigens and was similar to the effect of adding IL-1 to MLR cultures. These results demonstrate that human NK cells are capable of enhancing a T cell response.
Human Mononuclear Cells Which Produce Interferon-Alpha During NK(HSV-FS) Assays Are HLA-DR Positive Cells Distinct From Cytolytic Natural Killer Effectors
Authors: Fitzgerald-Bocarsly Patricia , Feldman Michael , Mendelsohn Monica , Curl Shelley , Lopez Carlos
Published: January 2018

Human mononuclear cells were previously shown to produce interferon-alpha (IFN) during 14 hr assays using herpes simplex virus type-1 infected fibroblasts [NK(HSV-FS)]. In this study, we have compared the effectors responsible for mediating NK(HSV-FS) cytolytic activity to those which produce IFN-alpha. Both activities were found to reside in non-adherent fractions, negative for non-specific esterase-staining cells. Like cells mediating NK cytolytic activity, IFN-alpha producing cells were found in light density Percoll gradient fractions. However, although NK(HSV-FS) and IFN production were largely overlapping, peak IFN production was consistently found in fractions slightly less dense than peak NK(HSV-FS) activity. IFN production was greatly augmented in fractions enriched for dendritic cells on hypertonic metrizamide gradients. The cells which produce IFN-alpha were phenotypically distinct from cytolytic NK effector cells: they lacked the Leu-11, Leu-7 and NKH1 cell surface markers shown to be present on both NK(HSV-FS) and NK(K562) effector cells. In addition, the IFN-alpha producing cells were found to be negative for a number of other markers characteristic of T cells, B cells or macrophages but were positive for Ia and HLA. The cells which produced IFN in response to UV-inactivated HSV antigen and to HSV-infected Raji cells were also found to be Leu-11 negative, and Ia positive. We conclude that the cells which produce IFN in response to HSV are a light density, Ia positive population which are distinct from NK cytolytic effector cells and co-purify with cells bearing a dendritic morphology. These results support our earlier findings that NK(HSV-FS) activity and IFN production are independent of one another and can segregate independently in vivo.
Characteristics of Binding of a Potent Chemotactic Formyl Tetrapeptide, Formylmethionyl-Leucyl-Phenylalanyl-Phenylalanine, to the Receptors on Rabbit Neutrophils
Authors: Kermode John C , Muthukumaraswamy Natesa , Freer Richard J
Published: January 2018

Binding of a potent chemotactic formyl tetrapeptide, formylmethionyl-leucyl-phenyl-alanyl-phenylalanine (fMet-Leu-Phe-Phe), to the formyl peptide receptors on the rabbit neutrophil was assessed by two approaches. A tritiated preparation of fMet-Leu-Phe-Phe was used for direct binding studies, whereas indirect studies comprised an assessment of the ability of the formyl tetrapeptide to competitively inhibit the binding of 35S-labeled formylmethionyl-leucyl-phenylalanine. These two approaches yielded analogous results. The formyl tetrapeptide fMet-Leu-Phe-Phe showed rapid and saturable binding to the same chemotactic receptors as the less potent formyl tripeptides with which it was compared. Its equilibrium-binding pattern, however, was different: fMet-Leu-Phe-Phe showed a homogeneous binding pattern, in contrast to the heterogeneity seen with the less potent compounds. The relative potencies for high-affinity binding of the two standard formyl tripeptides and fMet-Leu-Phe-Phe correlated well with their relative potencies for stimulating the biological response of degranulation; the relative potencies for low-affinity binding correlated less well.
Generation of Neutrophil Chemotactic Activity by Phorbol Ester-Stimulated Calf Pulmonary Artery Endothelial Cells
Authors: Gudewicz Paul W , Odekon Lale E , Del Vecchio Peter J , Saba Thomas M
Published: January 2018

Chemotactic activity for human polymorphonuclear leukocytes (PMNL) was detected in serum-free conditioned media 1 to 4 hr after monolayers of calf pulmonary artery endothelial cells were pretreated with phorbol myristate acetate (PMA). Chemotactic activity was increased in conditioned media following pretreatment with either PMA or the less lipophilic active phorbol ester, 4-β-phorbol-12,13-dibutyrate (P(Bu)2) in a dose-dependent manner. Chemotactic activity of conditioned media from PMA-treated endothelial cells was confirmed by checkerboard analysis. The chemotactic activity in conditioned media from PMA-pretreated endothelial cells was completely inhibited by pretreating endothelial cells with either cycloheximide, actinomycin D, or the lipooxygenase inhibitor, diethylcarbamazine. Furthermore, the chemotactic activity was heat-stable, inhibited by trypsin treatment, and present in both aqueous and lipid phases after ether extraction. The data demonstrate that pulmonary artery endothelial cells exposed to active phorbol esters release potent chemotactic factor(s) for PMNL. These findings suggest a role for activators of protein kinase C in mediating endothelial cell release of chemotactic factor(s) that may be important in the directed migration of circulating leukocytes to sites of vascular injury.
Thymic Stroma-Derived T-Cell Growth Factor (TSTGF): II. Biochemical and Functional Characterization
Authors: Sato Soichiro , Ogata Masato , Sano Haruo , Mizushima Yumiko , Muramatsu Minoru , Doi Hideyuki , Itoh Tsunetoshi , Hamaoka Toshiyuki , Fujiwara Hiromi
Published: January 2018

The culture supernatant (SN) from a cloned line of thymic stroma-derived cells in fibroblastic form (TSCF) contained a factor capable of supporting the growth of the interleukln (IL) 2-dependent, antigen-specific helper T cell (Th) clone 9-16 without requiring IL2 and antigen. This active substance, designated as thymic stroma-derived T-cell growth factor (TSTGF), was partially purified through DEAE-Sephacel chromatography and PBE 94 chromatofocusing. The original SN did not contain IL1, IL2, IL3, IL4, or interferon activities; but an appreciable magnitude of colony-stimulating factor (CSF) activity in addition to TSTGF was present, whereas the partially purified preparation of TSTGF was depleted of any type of CSF activity. The elution profile of TSTGF activity on the chromatofocusing has revealed that TSTGF has an isoelectric point (pI) of about 6.0. When a purified TSTGF sample was applied to Sephacryl S-200 column chromatography and sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, TSTGF activity was eluted in a single peak around an apparent molecular weight of about 25,000. The activity of TSTGF also was shown to be relatively stable with heat treatment and in the wide range of pH, but it was abolished by treatment with either trypsin or dithiothreitol. These results indicate that TSTGF, a novel T-cell growth factor, is the protein that has an apparent molecular weight of about 25,000 and a pI of 6.0, and in the intact molecule, it contains the disulfide bond(s) required to maintain and/or express its biologic activity.
Procoagulant Synthesis by Exudate and Bone Marrow-Derived Murine Macrophages
Authors: Shands Joseph W , Sunnenberg Thomas D , Lottenberg Richard
Published: January 2018

Murine exudate macrophages elicited by different stimuli and bone marrow-derived macrophages were studied for their capacity to synthesize factor VII and tissue factor in a basal state and on stimulation with endotoxin (LPS). Cells elicited by different stimuli varied in their production of both factors. Thioglycollate-elicited cells generally made more, but not significantly more, tissue factor in response to endotoxin than cells elicited with periodate or streptococci. Cells elicited with proteose-peptone, fetal calf serum (FCS), or LPS produced less or very little tissue factor. Thioglycollate-elicited cells and cells elicited with streptococci or proteose-peptone consistently made more factor VII than cells elicited with periodate, FCS, and LPS. Bone marrow-derived macrophages were responsive to LPS by the production of tissue factor by the fifth day of culture, and this rose to a maximum by day 10. The maximal production of factor VII occurred on day 5 of culture and declined with longer cultivation. Factor VII production was not enhanced by LPS, and prolonged cultivation in the presence of LPS turned off the synthesis of both tissue factor and factor VII. We conclude that exudate cells are heterogeneous in the production of coagulant factors and that the production of these factors varies with the maturity of the cells. In addition, the production of the tissue factor and the factor VII were not necessarily expressed in a coordinate fashion.
Two Distinct Cytolytic Mechanisms of Macrophages and Monocytes Activated by Phorbol Myristate Acetate
Authors: Chung Tejune , Kim Yoon B
Published: January 2018

Pulmonary alveolar macrophages (PAM) and peripheral blood monocytes (PBMO) of the miniature swine can be converted to cytolytically active effector cells by treating with phorbol myristate acetate (PMA) as determined by enhancement of cytotoxicity to various target cells. Kinetics of the PMA-activated PAM and PBMO in cytotoxicity show that the effective PMA concentration ranges from 10 to 1,000 ng/ml. Induction of cytotoxic macrophages and monocytes occurred as early as 30 min and to their maximum cytotoxicity after 1 hr exposure to PMA and the enhanced cytotoxic activity persisted up to 24 to 40 hr when PMA was removed by washing after 1 hr exposure, but prolonged exposure to PMA for more than 6 hr resulted in a drastic decrease of cytolytic activities suggesting the prolonged exposure to PMA causes macrophages and monocytes to become refractory to PMA stimulation. Target cells displayed varying degrees of cytotoxic sensitivity to the PMA-activated PAM and PBMO; PRBC, SRBC, and K562 were sensitive, WEHI-164 and U937 were relatively sensitive, and SB was very resistant to these activated effector cells. The mechanisms of PMA-induced cytotoxicity could largely be divided into two categories. One was the H2O2 mediated killing as shown by complete reduction of cytotoxicity after adding catatase in the assay. The other was the proteases mediated cytolysis, which could be blocked by protease inhibitors, Phenyl methyl sulfonyl fluoride (PMSF), and N- α-p-tosyl-L-lysine chloromethyl ketone (TLCK). H2O2 was the only mediator produced in large enough quantities from PBMO to kill target cells, whereas PAM could produce both mediators (H2O2 and proteases). PRBC, SRBC, and K562 appeared to be killed by H2O2 produced by PAM and PBMO. In contrast, U937 and WEHI-164 appeared to be killed by proteases in PAM mediated cytolysis but by H2O2 in PBMO-mediated cytolysis. These results suggest that the observed cytolytic mechanisms can be differed by type of target cells as well as the source of mononuclear phagocytes within the individual animal.
Influence of Platelet Activating Factor and a Nonmetabolizable Analogue on Superoxide Production by Bone Marrow Derived Macrophages
Authors: Storch J , Ferber E , Munder P G
Published: January 2018

Serum-free cultured macrophages could be stimulated for lucigenin-dependent chemiluminescence by platelet activating factor (PAF) and phorbol myristate acetate (PMA). Stimulation with PMA resulted in a desensitization against PAF, whereas prestimulation with PAF had no influence on a following response caused by PMA. The PAF analogue, 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (Et-18-OCH3), did not induce chemiluminescence by itself and desensitized the cells against PAF, like substimulating concentrations of PAF. PAF and PMA responsiveness was rapidly modulated in a similar manner during adherence of the cells to polystyrene tubes. At higher concentrations, Et-18-OCH3 as well as lysophosphatidylcholines potentiated PMA-induced chemiluminescence. The PAF analogue was most effective. Although PMA-induced chemiluminescence was stimulated at least 5-fold by Et-18-OCH3, this compound Increased the PMA-induced activation of protein kinase C only 1.39-fold. The priming effect of Et-18-OCH3 was not reduced in the absence of extracellular Ca2+ and after cell membrane depolarisation.
Infection of a Murine T-Cell Line With a Retrovirus Carrying c-myc Decreases the Interleukin-2 Cell Dependence by a Nonautocrine Mechanism
Authors: Shapiro Ilya M , Winberg Gösta , Stefanescu Irina , Wigzell Hans , Menezes José
Published: January 2018

A murine Interleukin-2 (IL-2)-dependent T-cell line, CTLL-2, was infected with a retrovirus carrying the mouse c-myc cDNA and the Tn-5 neogene. Transduced cells were selected in the presence of Geneticin sulfate (G418); these cells were shown to express both the endogenous and the transduced c-myc genes. The IL-2 requirement of these cells was then found to be significantly reduced. The cells did not express IL-2 mRNA nor did they produce an activity myogenic for CTLL-2 cells. This suggests that the reduction of IL-2 dependence observed following retroviral transduction of c-myc is caused by a nonautocrine mechanism.
Virus-Induced Enhancement of Arachidonate Metabolism by Bovine Alveolar Macrophages In Vitro
Authors: Laegreid W W , Taylor S M , Leid R W , Silflow R M , Evermann J R , Breeze R G , Liggitt H D
Published: January 2018

Virus infection of alveolar macrophages both in vivo and in vitro has been associated with a variety of changes in cellular function. Some of these changes are identical to the effects that arachidonate-derived mediators, prostaglandins, leukotrienes, and hydroxyeicosatetraenoic acids, have on macrophage function. Virus infection of macrophages has been previously shown to increase the output of some arachidonate metabolites, most notably PGE2. However, the effect of virus infection on arachidonate metabolism in general has not been well described. In our experiments, primary cultures of alveolar macrophages obtained from normal cattle by bronchoalveolar lavage, were infected in vitro with parainfluenza type 3 virus. At days 0 to 4 post-infection (p.i.) these cells were labelled with 3H-arachidonic acid and stimulated with either serum-coated zymosan, the calcium ionophore A23187, or phorbol myristate acetate. The complete spectrum of arachidonate-derived metabolites was determined by reverse-phase high performance liquid chromatography with UV and on-line radiometric monitoring of column eluant. The total output of metabolites of arachidonic acid by virus-infected alveolar macrophages was increased over that of noninfected controls (with all stimuli tested) by day 4 p.i. (P ≤ 0.05). The production of metabolites by the cyclooxygenase, 12-and 5-lipoxygenase enzyme systems was significantly increased, as was the release of 3H-arachidonate. The lack of stimulus specificity and the increases in arachidonate release suggest that greater substrate availability, due either to increased phosphollpase activity or direct virus-membrane interaction, may be responsible for the virus-induced enhancement of metabolite output.
Leukocyte Function in Pelger-Huët Anomaly of Dogs
Authors: Latimer Kenneth S , Kircher Ingrid M , Lindl Patricia A , Dawe Donald L , Brown John
Published: January 2018

Leukocyte function was evaluated in five dogs with Pelger-Huët (P-H) anomaly and in five control dogs. No significant differences were found between groups in neutrophil adherence, random movement, chemotaxis, phagocytosis, or bacterial killing of Staphylococcus intermedius. Neutrophils migrated rapidly into inflammatory sites where progressive nuclear lobulation was noted over time. Antibody titers to exogenous antigens were similar in the P-H and control groups indicating B- and T-lymphocyte cooperation in humoral immunity. Lymphocyte blastogenesis to phytohemagglutinin also was similar in both groups suggesting the presence of a responsive T-lymphocyte population. These findings indicate that no apparent predisposition to infection or immunodeficiency exists in dogs with P-H anomaly.
1,25-Dihydroxyvitamin D3 Induces Responsiveness to the Chemotactic Peptide f-Met-Leu-Phe in the Human Monocytic Line U937: Dissociation Between Calcium and Oxidative Metabolic Responses
Authors: Polla Barbara S , Werlen Guy , Clerget Michel , Pittet Didier , Rossier Michel F , Capponi Alessandro M
Published: January 2018

In the human premonocytic line U937, 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) induces a functional NADPH oxidase, that is responsive to both phorbol esters and opsonized zymosan. The chemotactic peptide f-Met-Leu-Phe (fMLP) did not. however, induce superoxide generation by these cells. This was not due to the absence of receptors for fMLP. Although there was no significant binding of [3H]-fMLP to undifferentiated U937 cells, preincubation with 1,25-(OH)2D3 induced expression of specific and saturable binding sites. Moreover, fMLP induced a rapid and reversible rise in cytosolic free Ca1+ concentration ([Ca2+]i) in 1,25-(OH)2D3-treated U937 cells, but not in control or 24,25-dihydroxyvitamin D3 (24,25-(OH)sD3)-treated cells. This [Ca2+]i response was dependent on concentrations of both fMLP and 1,25-(OH)2D3 and was observed at physiologic concentrations of the hormone (25 pM). The rise in [Ca2+]i induced by fMLP in 1,25-(OH)2D3-treated U937 cells was blocked by pertussis toxin and presumably mediated by inositol (1,4.5)-trisphosphate generation. These results indicate that in U937 cells differentiated with 1,25-(OH)2D3, inositol phosphate-mediated [Ca2+]i responses to fMLP are uncoupled from NADPH oxidase activation.
Both Recombinant Interleukin-1 (Beta) and Purified Human Monocyte Interleukin-1 Prime Human Neutrophils for Increased Oxidative Activity and Promote Neutrophil Spreading
Authors: Sullivan Gail W , Carper Holliday T , Sullivan James A , Murata Teizo , Mandell Gerald L
Published: January 2018

Both purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) primed neutrophils for increased superoxide production and chemiluminescence in response to f-met-leu-phe. In addition, purified human monocyte interleukin-1 and recombinant interleukin-1 (beta) altered neutrophil shape. Recombinant interleukin-1 (alpha) used at the same concentration of interleukin-1 (beta) did not prime neutrophils for increased superoxide production after stimulation with f-met-leu-phe. interleukin-1 expressed by monocytes in response to endotoxin stimulation could act as a modulator of neutrophil function.
Macrophage Function in Murine Allogeneic Bone Marrow Radiation Chimeras in the Early Phase After Transplantation
Authors: Roesler Joachim , Baccarini Manuela , Vogt Birgit , Lohmann-Matthes Marie-Luise
Published: January 2018

We tested several of the functions of macrophages (Mφ) in the early phase after allogeneic bone marrow transfer to get information about this important aspect of the nonspecific immune system in the T-cell-deficient recipient. On days 3-5 after transfer, the number of Mφ was reduced in the spleen, liver, lungs, and peritoneal cavity (Pe). The phagocytosis of sheep red blood cells (SRBC) by these Mφ was normal or even enhanced, as in the case of Pe-Mφ. Already on days 8-12 after transfer, the number of Mφ in spleen and liver exceeded that of controls, whereas the number was still reduced in lungs and Pe. We examined their ability to kill P815 tumor cells, to produce tumor necrosis factor-α (TNFα), to phagocytose SRBC, to produce reactive oxygen intermediates (ROI) in vitro and to kill Listeria monocytogenes in vivo. Most functions were normal and often even enhanced, depending on the organ origin, but the ability of Pe-Mφ to produce ROI was reduced. Proliferative response to macrophage colony-stimulating factor (M-CSF) and killing of YAC-1 tumor cells revealed a high frequency of macrophage precursor cells in the spleen and liver and a high natural killer (NK) activity in the liver. Altogether, enhanced nonspecific immune function, especially preactivated Mφ, may enable chimeras to survive attacks by opportunistic pathogens.
Pertussis Toxin Inhibits the FMLP-lnduced Membrane Association of Protein Kinase C in Human Neutrophils
Authors: Christiansen Niels Obel
Published: January 2018

The effect of pertussis toxin on N-formyl-methionyl-leucyl-phenylalanine (FMLP), phorbol 12-myristate 13-acetate (PMA), ionomycin, and A23187-induced translocation of protein kinase C and superoxide generation was studied in human neutrophils. Pertussis toxin was shown to inhibit FMLP-induced superoxide generation in parallel with an inhibition of protein kinase C translocation. In contrast, no effect of pertussis toxin was demonstrated upon superoxide generation or protein kinase C translocation in PMA-, A23187-, or ionomycin-stimulated cells. In that superoxide generation and protein kinase C translocation were inhibited in parallel, it is concluded that a G-protein-dependent cascade is involved in the FMLP-induced activation of protein kinase C, and this cascade may be equivalent to the pathway inducing superoxide generation.
Thymic Stroma-Derived T Cell Growth Factor (TSTGF): III. Its Ability to Promote T Cell Proliferation Without Stimulating Interleukin 2- or 4-Dependent Autocrine Mechanism
Authors: Kosaka Hiroshi , Ogata Masato , Sano Haruo , Sakuma Shozo , Mizushima Yumiko , Nakamura Etsuo , Teraoka Hiroshi , Hamaoka Toshiyuki , Fujiwara Hiromi
Published: January 2018

A thymic stroma-derived cell clone, MRL104.8a produced a T cell growth factor designated as thymic stroma-derived T cell growth factor (TSTGF). This factor that is distinct from previously described T cell growth factors such as interleukin (IL) 2 or 4 was capable of promoting the growth of IL2-dependent, antigen-specific helper T cell clones. While such growth promotion was induced without requirement of the relevant antigen and exogenous IL2, we further investigated whether it depended on activation of an IL2- or IL4-dependent autocrine mechanism. Helper T cell clones, 8-E and 8-5, were able to proliferate in response to stimulation with either antigen or TSTGF. 8-E and 8-5 produced IL2 and IL4, respectively, in cultures following antigenic stimulation, whereas neither IL2 nor IL4 activity was detected in cultures during TSTGF-induced proliferation. The proliferation of these helper T cell clones by antigenic stimulation was almost completely inhibited when anti-IL2 receptor or anti-IL4 antibody was added to the cultures. The addition of cyclosporin A (CsA) to cultures of 8-E and 8-5 clones together with antigen also resulted in the complete inhibition of cellular proliferation in association with the suppression of IL2 and IL4 production. In contrast, TSTGF-induced proliferation was not affected by addition of either type of antibody or CsA. These results indicate that TSTGF is a novel T cell growth factor that can exert its own growth-promoting effect without depending on an IL2- or IL4-operating autocrine mechanism.
Heterogeneity in Responses of Human Blood Monocytes to Granulocyte-Macrophage Colony-Stimulating Factor
Authors: Inamura Noriaki , Sone Saburo , Okubo Akio , Singh Sukh Mahendra , Ogura Takeshi
Published: January 2018

Granulocyte-macrophage colony-stimulating factor (GM-CSF) has stimulatory effects on various monocyte functions. We examined whether all or only some blood monocytes could respond to GM-CSF. Monocytes from peripheral blood of healthy donors were separated by size into five fractions by counter-flow centrifugal elutriation (CCE). The phagocytic activities of monocytes in these fractions depended on the size of the cells. On activation by bacteria-derived stimuli, these fractions showed similar responses of production of monokines such as interleukin-1 (IL-1) and tumor necrosis factor (TNF) and cytotoxicity against allogeneic tumor cells. On treatment of these fractions with optimal concentration of GM-CSF, fractions 3, 4, and 5 showed tumoricidal activity and produced cell-associated IL-1, fraction 3 producing the most, whereas release of IL-1 and TNF in the supernatant was not observed. The cell-associated IL-1 was identified as IL-1α, not IL-1β, by neutralizing tests with antisera against IL-1α and IL-1β. GM-CSF also induced the proliferative and colony-forming responses of medium and large monocytes. These observations suggest that adoptive therapy with macrophage progenitor cells in peripheral blood may be useful in combination with GM-CSF for treatment of monocytopenia after chemotherapy or radiation therapy.
Ultrastructural and Immunocytochemical Study of the Uptake and Distribution of Bacterial Lipopolysaccharide in Human Monocytes
Authors: Kang Yuan-Hsu , Dwivedi R S , Lee Che-Hung
Published: January 2018

Interaction of bacterial lipopolysaccharide (LPS) with monocytes stimulates production of a variety of mediators that are involved in the pathogenesis of septic shock and wound repair. We report here the mechanisms of LPS uptake and intracellular distribution of LPS in human monocytes. Ficoll-Hypaque-purified peripheral mononuclear cells (PBMC) were exposed to LPS from rough Escherichia coli (J5) or to biotin-conjugated LPS (biotin-LPS) from smooth E. coli (0111:B4), or to fluorescein isothiocyanate-conjugated LPS of E. coli (055:B5) at 37° for various times and processed for electron microscopy, immunocytochemistry, and flow cytometry. Monocytes were identified by the presence of numerous cytoplasmic peroxidase-positive granules or by monoclonal antibodies against monocyte. LPS micelles were identified by their specific bilayer structure, staining of horseradish peroxidase reaction product, or colloidal gold using biotin-LPS or a monoclonal antibody to LPS. Binding of LPS to cell surface was observed 5 min after incubation with LPS. Intracellular localization of LPS micelles was found 30 min following exposure to LPS. Prolonged incubation with LPS increased intracellular LPS. Intracellulary, LPS micelles were found in large membrane-bound vacuoles, in small vesicles, and in the cytoplasm and nucleus. They were also observed in association with the cytomembrane of various organelles. The overall results indicate that LPS may be taken up by monocytes by direct passive diffusion through ruptures of plasma membrane, pinocytosis, and phagocytosis, involving specific and/or nonspecific binding, and suggest that peripheral blood monocytes play an important role in clearance of LPS; that LPS may have broad effects on cell functions; and that the nonspecific binding to various cytomembranes may be destructive to cell organelles and cells in general.
Effects of Inflammatory Cytokines and Phorbol Esters on the Adhesion of U937 Cells, a Human Monocyte-Like Cell Line, to Endothelial Cell Monolayers and Extracellular Matrix Proteins
Authors: Cavender Druie E , Edelbaum Dale , Welkovich Linda
Published: January 2018

The accumulation of mononuclear phagocytes at sites of chronic inflammation is dependent on an increase in the rate of extravasation of blood-borne monocytes through the vascular endothelium into the connective tissue. Once the monocytes have emigrated into the connective tissue, they may differentiate into tissue macrophages, presumably following interactions with extracellular matrix proteins. To study these processes, we tested the effects of cytokines and phorbol esters on the adhesion of U937 cells, a human monocyte-like cell line, to cultured endothelial cells (EC) and to matrix proteins. In the absence of cytokines, very few of the U937 cells adhered to EC (5% or less in most experiments). When EC were pretreated for optimal periods of time (4–8 hr) with recombinant interleukin-1α (IL-1α), IL-1β, tumor necrosis factor-α (TNFα), or lymphotoxin (LT; also known as TNF-β), 35–85% of the U937 cells were able to bind. Interferon-γ (IFN-γ) and interleukin–2 (IL-2) did not stimulate U937-EC binding, even though IFN-γ was shown to increase EC adhesiveness for T lymphocytes. Phorbol esters also greatly stimulated U937-EC adhesion but, in this case, the increase was due to an action on the U937 cells. A monoclonal antibody (MAb), 60.3, against the CD11/CD18 family of leukocyte adhesion molecules partially inhibited the adhesion of untreated and phorbol ester-treated U937 cells to noncytokine-treated EC. However, that MAb had no effect on U937 cell binding to TNF-α-treated EC. Thus U937 cells use both CD11/CD18-dependent and -independent mechanisms to adhere to EC. In the absence of stimulating agents, only a small proportion of the U937 cells (2–20%) adhered to fibronectin (FN), and almost none bound to either laminin (LN) or gelatin (denatured type I collagen). In the presence of phorbol esters, a much larger proportion of the U937 cells adhered to FN, with only slight increases in the proportion of cells which bound to LN or gelatin. Additional adhesion assays performed in the presence of a pentapeptide containing the amino acid sequence arg-gly-asp (RGD), which is part of one of the cell-binding domains of FN, demonstrated that the RGD-containing peptide almost totally blocked the phorbol ester-induced adhesion of U937 cells to FN. In contrast, the peptide had no inhibitory effect on the phorbol ester-induced binding of U937 cells to EC.