bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional Characterization of Lymphokines From the EL-4 T Cell Line That Activate Macrophages for Nonspecific Tumor Cytotoxicity
Authors: Occhionero Massimo , Leonard Edward J , Meltzer Monte S 
Published: January 2018

Abstract
Culture fluids from a phorbol myristate acetate-stimulated EL-4 thymoma cell line were previously found to activate mouse macrophages to become nonspecifically tumoricidal. By gel filtration, 23,000- and 45,000-MW peaks were identified. In this study we compared EL-4 culture fluid activity with that obtained from antigen-stimulated mouse spleen cells. By four criteria, functional activity from the two sources was comparable: 1) Macrophage activation could be separated temporally into two steps, priming and triggering. 2) Macrophages activated by the fluids exhibited peak cytotoxic activity within 5–9 hr; no cytotoxic activity was demonstrable if addition of target cells was delayed 14 hr. 3) Mouse peritoneal exudate macrophages, but not resident macrophages, became cytotoxic after a 5-hr incubation with culture fluids. 4) Macrophages from certain strains of mice were incapable of activation; the same pattern of strain unresponsiveness was observed with both EL-4 and spleen cell culture fluids. Thus, it is likely that the two EL-4 products and the mouse spleen cell lymphokine activate the same cytotoxic mechanism.
Macrophage Activation Measured by Changes in 5′-Nucleotidase and Alkaline Phosphodiesterase I Activities After Infection of Newborn and Juvenile Guinea Pigs With Mycobacterium microti
Authors: Bautista Abraham P , Solomon J Brian 
Published: January 2018

Abstract
Activation of alveolar, peritoneal, liver, and spleen macrophages was measured by decreased 5’-nucleotidase and elevated alkaline phosphodiesterase I activities in newborn and juvenile guinea pigs for up to 48 days after intracardiac or intranasal infection with Mycobacterium microti. Increased AP and reduced 5’-nucleotidase activity in cell lysates of macrophages appeared to be related to the carrier state during infection. Intranasal infection of 8-week-old guinea pigs with M. microti produced decreases of 5’-nucleotidase activity in alveolar macrophages during 1–8 weeks post infection and in macrophages from all four sources from 4–8 weeks.
Serum Lysozyme Increased by Fructose-1, 6-Diphosphate in Men, Rabbits, and Mice
Authors: Tarsi R , Ripa S , Simonetti N , Lazzarino G 
Published: January 2018

Abstract
Fructose-1, 6-diphosphate hydrated sodium salt (FDP), intravenously injected, remarkably stimulates the production of serum lysozyme in man, rabbit, and mouse with a different kinetics in each of them: Man and rabbit show, in the first hour, a concentration peak followed by a slow decrease, whereas in mouse the concentration is less variable with time.
Superoxide Generation by Neonatal and Adult Rabbit Alveolar Macrophages
Authors: Sherman Michael P , Lehrer Robert I 
Published: January 2018

Abstract
We compared the abilities of alveolar macrophages (AM) from neonatal and adult rabbits to generate and release superoxide (O2) after exposure to soluble and particulate stimuli. Basal rates of O2 release, 0.1–0.2 nmol/106AM/10 min, were modestly increased by exposing AM to phorbol myristate acetate, (dihy-dro)cytochalasin B, or cytochalasin C. Opsonized zymosan was a more effective stimulus, and maximal rates of O2 release were observed when AM were stimulated by a combination of opsonized zymosan and one of the aforementioned cytochalasins. Cytochalasins D and E were each potent activators of O2″ production by AM in the absence of additional stimuli. Adult AM released 24.8 ± 6.0, 20.4 ±4.4, and 33.5 ± 6.4 nmol O2- /106AM/10 min after stimulation by cytochalasin D, cytochalasin E, and dihydrocytochalasin B plus opsonized zymosan, respectively. Following exposure to the same stimuli, AM from 1, 3- and 7-day-old rabbits released O2″ at rates that ranged from 45 to 75% of corresponding adult values. The discrepancy between O2 production by neonatal and adult AM was accentuated when comparisons were restricted to AM recovered from bacteriologically sterile respiratory tracts. Our data show the O2 generating capacity of neonatal AM to be substantially less than that of the adult AM. Immaturity of this response could predispose neonates to pulmonary infection.
A Human Lymphokine Activates Macrophage C3 Receptors for Phagocytosis: Studies Using Monoclonal Anti-Lymphokine Antibodies
Authors: Griffin Frank M , Luben Richard A , Golde David W 
Published: January 2018

Abstract
We have identified a human T lymphocyte cell line, the Mo line, that constitu-tively elaborates a lymphokine that activates macrophage receptors for the third complement component (C3) for phagocytosis. The molecule is physically, functionally, and immunologically very similar, if not identical, to a previously characterized murine lymphokine. Both molecules were inactivated by the same physical and chemical treatments, activated macrophage C3 receptors for phagocytosis, and freed macrophage C3 receptors to move within the cell's plasma membrane. In addition, both the human and the murine products were recognized by the same monoclonal antibodies. Treatment with monoclonal antibodies abolished both the ability of lympho-kine-containing supernatants to mobilize macrophage C3 receptors and the supernatants' ability to activate C3 receptor-mediated phagocytosis. The dose-response curves for both effects of the antibodies were identical, strongly suggesting that a single molecule was responsible for both effects and that the lymphokine activated macrophage C3 receptors for phagocytosis by freeing the anchored receptors and allowing them to diffuse within the cell's plasma membrane. These findings strengthen the hypothesis that, for a receptor to promote phagocytosis, it must be able to diffuse within the macrophage plasma membrane.
Recruitment of Neutrophils by an Encapsulated Coagulase-Negative Strain of Staphylococcus simulans in the Mammary Gland of the Mouse
Authors: Anderson J C , Craven N 
Published: January 2018

Abstract
The encapsulated coagulase-negative strain of Staphylococcus simulans (strain 76) was inoculated into the mammary glands of lactating mice. In contrast to the coagulase-positive encapsulated Staphylococcus aureus (strain M), which elicited a neutrophil response within 18 hr, strain 76 organisms multiplied in the glands but failed to elicit a neutrophil response for 3 days; they were then eliminated from the gland by 8 days. When strain 76 was inoculated into mice whose offspring had been removed 3 days earlier, a neutrophil response was induced within 18 hr and, although phagocytic ingestion was resisted for at least 42 hr, the organisms were eliminated from most glands within 5 days. Inoculation of a naturally occurring double-stranded RNA (BRL 5907) into the mammary gland induced a macrophage infiltration of the alveolar lumen that was qualitatively similar to 3 days involution. Intramammary inoculation of strain 76 18 hr after BRL 5907 resulted in a neutrophil infiltration within 6 hr. In vitro, strain 76 stimulated the release of chemotactic factors for neutrophils from bovine mammary gland macrophages. The results suggest that the recruitment of neutrophils by strain 76 in the mammary gland of the mouse is mediated by macrophages.
The Intravenous Intralipid Tolerance Test
Authors: Fraser Ian , Pearson Henry , Bowry Veena , Bell P R F 
Published: January 2018

Abstract
The half-life of an intravenously injected bolus of intralipid 20% was measured in normal rats in order to asess its relationship to reticuloendothelial system (RES) activity. Groups of animals were studied following various treatments, and the results compared to measurement of carbon clearance in similar groups. The RES effects of silica and C parvum were confirmed by the carbon clearance test, but no effect was seen on the half-life of intralipid. Intralipid clearance was shortened by fasting and the administration of intravenous heparin, neither of which affected carbon clearance. It is concluded that the intravenous intralipid test has no place in the asessment of RES function.
Bovine Alveolar Macrophages: Phenotypic and Functional Properties of Subpopulations Obtained by Percoll Density Gradient Centrifugation
Authors: Ohmann H Bielefeldt , Babiuk L A 
Published: January 2018

Abstract
Bronchoalveolar cells retrieved from conventionally raised, healthy calves were separated into four fractions on a discontinuous Percoll density gradient. The alveolar macrophage (AM) subpopulations and nonseparated AM were assayed for such phenotypic markers as la-antigen, ectoenzymes, and immune receptors, as well as for functional activity in antibody-dependent cellular cytotoxicity (ADCC) against virus-infected cells, superoxide anion generation, and their influence on lectin-induced lymphocyte proliferation. The low-density fraction was composed of large cells with low la-antigen expression, low ADCC activity, and high ecto-enzyme and C3b-receptor activity. In contrast the high-density fraction contained mainly small, monocytelike cells, with high la expression and low-level expression of most other markers and functions. Two fractions of intermediary density overlapped in most of the characteristics, but could be distinguished on the basis of ADCC activity, interleukin-1 generation, and the level of leucine amino peptidase activity.
Flow Cytometric Characterization of Alveolar Macrophages
Authors: Lehnert Bruce E , Valdez Yolanda E , Fillak David A , Steinkamp John A , Stewart Carleton C 
Published: January 2018

Abstract
Phenotypes of lung free cells (FC) harvested from Fischer-344 rats by episodic lavage were characterized by flow cytometry. Parameters evaluated included electronic volume (EV), axial light loss (ALL), 90° light scatter (LS), blue autofluorescence (BA), and green-yellow autofluorescence (G-YA). Three phenotypic populations, FC-A, FC-B, and FC-C were identified by their differing LS characteristics. FC-C represented 90% of the cells and were exclusively alveolar macrophages. Two subpopulations in FC-C, FC-CI and FC-CII, were further distinguished by their unique ALL features. The morphologic appearances of these subpopulations by light microscopy clearly differed in sorted preparations. Based on their patterns of autofluorescence, these FC-CI and FC-CII phenotypes were found to be composed of eight subpopulations. In FC populations harvested during further lavage episodes of the same lungs, the relative contributions of FC-CI to the FC-C subpopulation decreased as FC-CII correspondingly increased. This study demonstrates 1) that subpopulations of lavaged AM can be categorized according to their optical phenotypes by flow cytometry and 2) that the relative frequency of retrieval of some phenotypes depends on how exhaustively the lungs are lavaged. With regard to the latter, bronchoalveolar lavage does not randomly sample the underlying AM population in the alveolar compartment.
Release of a Chemotactic Monokine Upon Treatment With Lymphocyte Supernatants
Authors: Jutila Mark A , McIvor Keith L 
Published: January 2018

Abstract
Macrophages produced and/or released a chemoattractant(s) for neutrophils after having been treated for 2 hr with soluble products from two lymphoma cell lines. Culture supernatants of the EL-4 and Yac-1 cell lines, but not sarcoma I, Bc100, or the macrophagelike cell line P388d1, triggered the release of the chemoattractant. The macrophage-derived chemoattractant (MDC) was detectable within 2 hr following triggering and culture supernatants had maximal activity by 48 hr. The triggering of the macrophages to release the chemoattractant and the activity of the chemoattractant was not dependent upon any component of fetal bovine serum. Activation of complement was also not involved, since activated serum did not competitively inhibit the chemotactic activity of the macrophage-derived chemoattractant. The chemoattractant was macromolecular, stable to heating at 90° for 15 min, sensitive to pronase and chymotrypsin, and was affected by treatment with low pH.
Self-Limitation of the Oxidative Burst of Rat Polymorphonuclear Leukocytes
Authors: Mege Jean Louis , Capo Christian , Benoliel Anne Marie , Bongrand Pierre 
Published: January 2018

Abstract
The oxidative response of rat polymorphonuclear leukocytes stimulated by phorbol myristate acetate and N-formyl-methionyl-leucyl-phenylalanine was studied. Ferricytochrome reduction and peroxidase-catalyzed decrease of scopoletin fluorescence were used to monitor O2− and H2O2 release in the extracellular medium. Oxygen consumption was also measured in some experiments. Decrease of chlortetracyclin fluorescence after stimulation of dye-loaded cells was used to study an early step of cell stimulation. Finally, a possible relationship between cell responses and the medium redox potential was explored. Three major conclusions were obtained: 1) Ferricytochrome reduction is dependent on the total cytochrome concentration, and a simple mathematical model allows a tentative estimate of total superoxide anion production by stimulated cells. 2) Increasing cell concentration results in a decrease of individual cell response, and this may be accounted for by a direct inhibition of cell-released hydrogen peroxide on the reactivity of leukocytes. Further, H2O2 may be shown to inhibit an early step of cell response. 3) The solution redox potential does not influence cell reactivity, since it may be dramatically decreased without inhibiting cell response.
Localization of Antibody-Forming Cells in Draining Lymphoid Organs During Long-Term Maintenance of the Antibody Response
Authors: Donaldson Stephen L , Kosco Marie H , Szakal Andras K , Tew John G 
Published: January 2018

Abstract
Previous studies on the “spontaneous antibody response” have included in vitro steps and it is possible that the response is an in vitro artifact. The objective of the present study was to induce a spontaneous antibody response entirely in vivo and determine if the response is localized and if the magnitude of the response is related to the location of persisting antigen. Antigen was injected into the right hind footpads of mice, and lymph nodes on the right side were draining and lymph nodes on the left side were controls. Antibody-forming cells (AFCs) were enumerated in both draining and nondraining nodes 2 weeks, 2 months, and 1 year after secondary immunization. Four days prior to determining AFC number, the mice were severely bled to stimulate AFC production. Thousands of AFCs were found in the draining lymph nodes and the numbers were dramatic in nodes closest to the injection site that retain the most antigen. In contrast, the vast majority of nondraining nodes lacked any AFCs. One year after immunization, the response was almost exclusively in the popliteal node, draining the foot where antigen was administered a year earlier. These results are consistent with previous data on the spontaneous response and support the hypothesis that antigen retained on FDCs is essential in the maintenance of serum antibody levels.
Establishment and Characterization of a Novel Bone-Marrow-Derived Macrophage-Like Accessory Cell Line
Authors: Apte Ron N , Huleihel Mahmoud , Tuvia Yosef , Buchnik Dina , Weinstein Yacob , Segal Shraga 
Published: January 2018

Abstract
An accessory cell line, designated line A, was generated from bone marrow stem cells which differentiated in vitro in response to colony-stimulating factor (CSF) in substratum cultures. The cells were found to constitutively secrete large amounts of CSF, the activity of which was neutralized by anti-CSF-1 antibodies. Cells of line A and its supernatants potentiate the suboptimal response of thymocytes to PHA, manifesting an interleukin-1 (IL-1)-like activity. Culture fluids of this line also reconstitute the response to T cell mitogens of spleen cells depleted of adherent accessory cells. It was also found that cells of line A bear low levels of surface la, and they efficiently present soluble antigen to proliferating memory T cells. Constitutive prostaglandin secretion, which sometimes masks antigen-presenting capacity, was also demonstrated. Cells of line A are poorly phagocytic, do not secrete lysozyme, and lack Fc and complement receptors. However, they manifest strong cytoplasmic nonspecific esterase staining and an ectoenzyme profile resembling that of elicited inflammatory macrophages. In addition, the cell surface antigen Mac-2 was demonstrated, while stainings with anti-Mac-1 and anti-Mac-3 were negative. Thus, line A may represent a unique subpopulation of immunoregulatory accessory cells, the features of which are discussed.
Flow-Cytometric and Ultrastructural Analysis of Alveolar Macrophage Maturation
Authors: Kradin Richard L , McCarthy Karin M , Preffer Frederic I , Schneeberger Eveline E 
Published: January 2018

Abstract
Alveolar macrophages (AM) from adult and newborn rats were studied by flow cytometry and ultrastructural morphometry. We observed that the laser scatter and autofluorescent properties of newborn macrophages were different from those of adult cells. Relative to the adult AM, the forward-angle laser scatter obtained with the newborn AM was reduced; this optical measurement appeared to correlate with the smaller mean size, as determined by ultrastructural and electronic volume measurements. The diminished right-angle laser scatter (90° angle) correlated with the presence of fewer small, irregularly shaped lysosomal structures in the newborn AM, compared with AM from adult animals. AM from 1–2-day-old rats displayed large vacuoles containing multilamellar structures, which proved to be less effective at scattering light. Cells from newborn rats were less autofluorescent, a finding that appeared to correlate best with the numbers of secondary lysosomes. Flow cytometry may be used to discern structural alterations that occur during the maturation of AM. These changes correlate well with quantitative ultrastructural analyses of these cells.
Fc Receptor Function on Sheep Alveolar Macrophages
Authors: Fleit Howard B , Weiss Rachelle A , Chanana Arjun D , Joel Darrel D 
Published: January 2018

Abstract
We have examined the binding to sheep alveolar macrophages (AM) and peripheral blood polymorphonuclear leukocytes (PMN) of sheep immunoglobulin G subclasses or rabbit IgG immune complexes formed between rabbit anti-DNP IgG and DNP-bovine serum albumin. Binding studies using 125I-rabbit IgG immune complexes demonstrated 6.6 ± 3.5 × 104 receptors per alveolar macrophage; these receptors bound immune complexes with an average association constant of 3.3 × 107 M−1. Saturation binding was achieved by 90 minutes at 4° with 6 × 10−8 M IgG. Binding of subclasses of sheep IgG was examined by immunofluorescence. Only 10% of alveolar macrophages bound monomeric IgG1 and no binding of sheep IgG2 monomer could be demonstrated. In contrast, most peripheral blood PMN (93.0 ± 9.5%) bound IgG2, but not IgG1. No binding to adult peripheral blood PMN of rabbit IgG immune complexes could be demonstrated. To study further the development of pulmonary host defense, we examined the expression of receptors for IgG immune complexes (Fcγ R) on alveolar macrophages obtained from animals aged 8 through 180 days. At 8 and 21 days of age, the number of FcγR varied considerably (75,000–192,000 sites per cell) and equalled or even exceeded that of adult sheep. FcγR number declined by 42 and 90 days of age, where a nadir was reached (37,000 ± 6,000 and 25,000 ± 6,000 sites, respectively). By 180 days of age, the number of receptors had approached those of normal adult sheep (70,000 ± 20,000 sites per cell). These studies parallel previous observations that revealed age-related differences in the phagocytic capacity of ovine alveolar macrophages.
Pretreatment of Human Lymphocytes With Interferon Enhances the Synthesis of Interferon in Cocultures With Allogeneic Cells
Authors: Weigent Douglas A , Stanton G John 
Published: January 2018

Abstract
Human lymphocytes pretreated with interferon (IFN) alpha, beta, or gamma produced 17 times more IFN alpha (600–10,000 units/ml) than nontreated lymphocytes when cocultivated with allogeneic cells. Significant increases in IFN production (500–3,000 units/ml) were observed when lymphocytes were treated with IFN for just 2 h, and peak levels (10,000 units/ml) were produced after a 4-h treatment. The amount of IFN required to show the maximum priming effect was between 100 and 1,000 units; higher levels of IFN were inhibitory. The levels of IFN increased as the lymphocyte-to-target-cell ratio increased from 2:1 to 10:1 and decreased at higher ratios. The decrease in IFN production at higher ratios of lymphocytes to target cells could not be attributed to the presence of a soluble suppressor substance. The additional IFN found in supernates was attributed to enhanced production of IFN by the same cells, rather than recruitment of more cells to produce IFN. This conclusion is based on the fact that no increase in the number of cells staining positive for IFN production was observed in primed lymphocytes. The increased amount of IFN due to priming enhanced both nonsensitized cytotoxic activity and the transfer of antiviral activity, which could be prevented by antibody to IFN. The data suggest that priming may be an important biological mechanism for obtaining significant levels of IFN more rapidly in the vicinity of transformed cells or virus-infected tissues.
Sensitization of Tumor Target Cells to Cytolysis by Murine Macrophage Cytolytic Factor by Drugs Inhibiting DNA, RNA, and Protein Synthesis
Authors: Souchek J M , Leroux M E , Klostergaard J 
Published: January 2018

Abstract
The mechanism(s) with which tumor target cells actively resist the lethal lesion induced by murine macrophage cytolytic factory (CF) has been probed by drug-induced sensitization of these cells. We have examined whether drug-induced sensitization is attributable to the action of these drugs on cellular DNA, RNA, or protein synthetic rates. The murine mammary adenocarcinoma cell line EMT-6 pretreated with a dose range of actinomycin-D (.03-3.0 μg/ml) for 4 hr was inhibited from 66 to 98% in DNA synthesis rate, from 81 to 93% in RNA synthesis rate, and from 38 to 52% in protein synthesis rate. The maximum sensitization toward lysis by CF was achieved with a drug dose of 1.0 μg/ml. The lack of correlation between the drug-induced effects on sensitization and effects on these metabolic rates was evident from the correlation coefficients for the percentage of maximum sensitization of the target toward CF-induced lysis, and the percent of inhibition of DNA, RNA, and protein synthesis. These were 0.11, -0.11, -0.44, respectively. Similarly, target cells treated with a dose range of cycloheximide (0.3-30 μg/ml) were inhibited from 81 to 95% in DNA synthesis rate, 68 to 81% in RNA synthesis rate, and 82 to 93% in protein synthesis rate. However, at none of the drug levels employed was significant sensitization of the target cell to CF-induced lysis observed. This was reflected in the correlation coefficients of -0.55, -0.28, and -0.34 for DNA, RNA, and protein synthetic rates, respectively. The essential role of cellular microtubule-dependent events early in the lytic mechanism was demonstrated by exposing colchicone-treated targets to CF. While colchicone could markedly inhibit lysis if introduced before CF, this inhibitory effect was not detected if the drug were withheld for 4 hr after CF exposure. The importance of the repair mechanism(s) early in the cellular response to lesion formation