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Griffith R L - - 1988
Human macrophages play a key role in atherogenesis and are believed to be the progenitors of the cholesteryl ester (CE)-laden foam cells present in early atherosclerotic lesions. Several mechanisms by which macrophages accumulate CE have been recently described. One involves a perturbation in LDL metabolism subsequent to macrophage activation. Thus, ...
Aviram M - - 1988
Cholesterol-loaded human monocyte derived macrophages secrete distinct class of lipoprotein. Following macrophages incubation in serum-free medium containing [14C]-oleic acid the cells secrete lipoprotein associated radioactivity that was found in triglycerides, phospholipids and cholesteryl ester. Macrophage lipoprotein secretion was analyzed by non-denatured gradient gel electrophoresis, agarose lipoprotein electrophoresis and discontinuous density ...
Steinberg D - - 1988
Previous studies from this laboratory have shown that oxidative modification of low-density lipoprotein (LDL) causes it to be recognized by the scavenger receptor of the macrophage. Consequently, the rate of degradation of oxidized LDL by macrophages can be 3 to 10 times that of native LDL. Antioxidants, such as probucol, ...
Falcone D J - - 1988
The ability of acetyl-LDL to stimulate macrophage-dependent plasminogen activation and degradation of extracellular matrix was examined. We have found that expression of plasminogen activator activity in response to the scavenger receptor ligand varied among cell populations. Exposure to acetyl-LDL stimulated plasminogen activator expression by cells which constitutively released low levels ...
Zwadlo G - - 1988
Using a monoclonal antibody to macrophage migration inhibition factor (MIF), two proteins were isolated from supernatants of Concanavalin A-stimulated human peripheral blood mononuclear cells which seem to have complexed to a third component carrying the MIF activity. They are therefore designated MIF-related proteins or MRP-8 and MRP-14 according to their ...
Miyagawa N - - 1988
The effect of human C-reactive protein (CRP) isolated and purified from pooled patients' sera on macrophage function, especially on macrophage migration, was studied. Peritoneal exudate cells (PEC) from guinea pigs were used for macrophage migration inhibition (MMI) test of capillary method. Migration of either PEC or adherent purified macrophages exposed ...
Massmann J - - 1988
Interendothelial and subendothelial monocytes/macrophages are extremely rare in normal rabbit aortas compared with humans and swine, as has been shown by the present study and previous investigations of surface preparations. Light microscopy was used to study the development of immune complex-induced hematogenic macrophage infiltrations in 26 rabbits from the 4th ...
Malorny U - - 1988
The kinetics of appearance of MIF+ cells was investigated in experimental contact dermatitis using a monoclonal antibody (7D10) against murine MIF which was reacted with cryostat sections of tissues and detected by the indirect immunoperoxidase test. Four groups of BALB/c mice were investigated: (1) sensitized with 2,4-dinitrofluorobenzene (DNFB); (2) unsensitized ...
Tabas I - - 1987
Cholesteryl ester (CE) accumulation in arterial wall macrophages (foam cells), mediated by the intracellular enzyme acyl coenzyme A:cholesterol acyl transferase (ACAT), is a prominent feature of atherosclerotic lesions. However, native low density lipoprotein (LDL) does not cause activation of ACAT or CE accumulation in cultured mouse peritoneal macrophages despite both ...
Weinstock J V - - 1987
Enteric immunization with schistosome ova results in a diminished granulomatous response. This study explored a mechanism by which enteric immunization may decrease granuloma size. Granulomas from livers of acutely infected mice were dissociated and the dispersed cells were depleted of macrophages. As defined by a direct in vitro migration inhibition ...
Quinn M T - - 1987
Previous studies in this laboratory established that low density lipoprotein (LDL) incubated with cultured endothelial cells, smooth muscle cells, or macrophages undergoes free radical-catalyzed oxidative modification that generates lipid peroxides and extensive structural changes in the LDL molecule. The oxidatively modified LDL strongly inhibited chemotactic responses of the mouse resident ...
Lopes-Virella M F - - 1987
To determine whether stimulation of macrophages with products related to, or released as a consequence of, infectious processes could play a role in inducing the formation of foam cells, we studied the metabolism of native and acetylated low density lipoprotein (LDL) by human macrophages stimulated with lipopolysaccharide (LPS), muramyl dipeptide ...
Marcus Z H - - 1987
Human seminal plasma from normal or patients with abnormal parameters of the ejaculates contains an inhibitory material that expresses potent in vitro inhibitory activity on PHA-M-induced blast transformation and NK activity. Using the test of inhibition of NK activity, the semen samples from individuals with higher concentrations of fructose had ...
Okuyama H - - 1986
These experiments were undertaken to clarify whether or not suppressor macrophages contribute to deficiency of delayed-type hypersensitivity induced by BCG CW immunization in B6/lpr mice. Addition of indomethacin in vitro did not increase MIF production by immunized lpr lymph node cells. Adherent cells in lymph node cell suspensions from lpr ...
Yatsu F M - - 1986
Foam cells are lipid-laden macrophages derived primarily from circulating mononuclear cells and are a characteristic feature of atheromatous lesions. The exact role of these foam cells in the pathogenesis of atherosclerotic lesions remains uncertain, but one potential function is to take-up and process excess interstitial arterial lipoproteins, suggested by their ...
Gordon M R - - 1986
The production of a macrophage migration enhancement factor (MEF) has been achieved as a consequence of administering a desensitizing dose of purified protein derivative (PPD) to Mycobacterium bovis BCG-sensitized rabbits. The migration-enhancing effect was first demonstrated when alveolar macrophages (AM) harvested from desensitized rabbits exhibited marked migration stimulation; whereas maximum ...
Klimov A N - - 1985
Immune complexes consisting of human [125I]LDL or [125I]VLDL and anti-apo B IgG were prepared in vitro. After intravenous administration of these complexes or free LDL to normal rabbits the elimination rate for complexes was 2-3-fold higher than for free lipoproteins. The liver/spleen radioactivity ratio after administration of immune complexes was ...
Suko M - - 1985
The systemic injection of high doses of antigen into a previously immunized animal results in a state of transient anergy with respect to cell-mediated immune reactions. This phenomenon is known as desensitization. We have previously shown that desensitization is a multistage process. The initial 24-hr period is characterized by excessive ...
Takata I - - 1985
Alveolar macrophages (AM), harvested from the lungs of untreated normal young rabbits (New Zealand White) 14 days to 8 weeks of age, exhibited a state of migration stimulation compared to AM from normal adult rabbits (5 to 6 months of age). Migration of AM from normal adult rabbits (New Zealand ...
Cathcart M K - - 1985
Free radicals are believed to be involved in leukocyte induced tissue injury. The present studies were performed to determine whether low density lipoprotein (LDL) might serve as a mediator of tissue injury after leukocyte induced free radical oxidation of LDL. Our results show that incubation of LDL with monocytes or ...
Liu D Y - - 1985
The role of carbohydrate in the interaction of human migration inhibitory factor (MIF) with human peripheral blood monocytes was investigated by studying the effects of different exoglycosidases on the cellular response to MIF. When monocytes were pretreated with neuraminidase, an exoglycosidase specific for sialic acid, they became unresponsive to MIF. ...
Prokić L M - - 1985
While the influence of 2-mercaptoethanol (2-ME) on the functions of lymphocytes has rather extensively been investigated, there are almost no data on the action of this thiol compound on macrophages. We examined the effect of 2-ME in vitro (10(-6)-10(-4) M) on migration from capillary tubes of oil elicited peritoneal macrophages ...
Schwartz C J - - 1985
With an increasing interest in the role of the monocyte-macrophage in the pathogenesis of atherosclerosis and as a progenitor of plaque intimal foam cells, a model for the study of foam-cell differentiation in an extravascular environment has been developed. Granulomas were induced in 25 normocholesterolemic (NC) and 28 hypercholesterolemic (HC) ...
Tabas I - - 1985
Cholesteryl ester (CE)-loaded macrophages (foam cells) are a prominent feature of atherosclerotic plaques. Previous studies have shown that human monocytes or resident mouse peritoneal macrophages accumulate CE in response to low density lipoprotein (LDL) only when the LDL has been appropriately chemically modified. By contrast, we report here that J774 ...
Higuchi M - - 1984
Human MAF-C (macrophage-activation factor for cytotoxicity)-producing hybridoma H2-E3-5 was prepared by somatic cell fusion of PHA-activated peripheral blood lymphocytes with emetine/actinomycin D-treated cloned human acute lymphatic leukemia cells (CEM). The following activities were assayed: (1) macrophage-migration-inhibitory factor (MIF), (2) macrophage-activation factor for glucose consumption (MAF-G), (3) macrophage-activation factor for O2-formation ...
Edwards R L - - 1984
Human monocytes generate the procoagulant tissue factor (MTF) following exposure to a variety of immune stimuli in vitro. The generation of MTF is modified by T cells, lymphokines, and immunoregulatory lipoproteins, and recent studies have shown that MTF can be activated in an immune-specific manner following exposure to antigen. We ...
Naukkarinen A - - 1984
The effects of rabbit anti-chicken macrophage serum (RACMS) on the immune response in chickens stimulated locally with sheep red-blood cells (SRBC; T cell-dependent antigen) were studied, and the morphological alterations in the diffusely infiltrated area (DIA; T cell region of the bursa) were measured morphometrically. The response to SRBC was ...
Hotez P J - - 1984
Lysates of the haematoprotozoa Trypanosoma brucei or Plasmodium berghei stimulated murine peritoneal exudate cells to release a mediator, which suppressed lipoprotein lipase activity in differentiating 3T3-L1 preadipocytes. The parasite-induced mediator suppressed the activity of cell surface lipoprotein lipase up to 39% in a dose dependent manner. By impairing the activity ...
Wolf R - - 1984
Drug induced allergic reactions in treated patients are sometimes accompanied by laboratory evidence of a simultaneous drug-specific humoral and cellular immunity. The relationship between the two types of immune response was studied in an experimental model. In the present studies ICR mice were sensitized with horse serum to induce an ...
Boswell J M - - 1984
Mononuclear phagocytes comprise populations of both stationary and wandering cells in vivo, and play many important roles, including major ones in host defence and the regulation of the immune response. They also interact with fibroblasts in the production and degradation of collagen and are therefore responsible in part for the ...
Khoo J C - - 1984
High levels of neutral triglyceride lipase activity have been demonstrated in several types of macrophages (J774 cells, human monocyte/macrophages, rabbit alveolar macrophages, and resident mouse peritoneal macrophages). The pH optima ranged from 6.5 to 7.4 depending upon the buffer and the conditions of incubation. The addition of bovine serum albumin ...
Sorg C - - 1984
It has been described before that only certain types of macrophages are capable to respond to lymphokines and that only certain macrophage phenotypes were able to migrate and to respond to migration inhibitory factors (MIF). With respect to the dissociation of MIF activities from a series of other biological activities, ...
Peck R - - 1984
Guinea pig lymph node cells stimulated with concanavalin A (Con-A) were used as a source of lymphokines. Purifications by molecular sizing columns yielded sufficient quantities of macrophage activating factor (MAF)-active fractions to allow immunization of rabbits. An antiserum was produced which is capable of specifically inhibiting MAF activity, as well ...
Peck R - - 1983
A method is described for quantitating the biological activity of macrophage migration inhibitory factor (MIF) based on the detection of macrophages migrating from agarose droplets. The migration is determined with polyclonal anti-macrophage antibodies in an ELISA assay. The numbers of macrophages thus detected correlate well with the migration as measured ...
Mizushima A - - 1983
The macrophage migration inhibitory factor (MIF) fraction was prepared from the immunoadsorbent column by using anti-guinea pig MIF antiserum. Suppression of cutaneous delayed-type hypersensitivity was achieved by intraperitoneal injection of the MIF fraction into the animals bearing macrophage-rich peritoneal exudates. Skin reactions induced by phytohemagglutinin (PHA) were also suppressed in ...
Wannamaker L W - - 1983
Few of the cellular components of group A streptococci appear to be directly toxic for animals or humans. Some preparations of M protein produce an immunotoxic effect on human platelets and neutrophils. Cell wall fragments produce a chronic multinodular inflammatory lesion of dermal connective tissue. The peptidoglycan component of cell ...
Leu R W - - 1983
Guinea pig macrophage populations previously established to be either responsive or refractory to activation by migration inhibitory factor (MIF) and Lotus fucolectin in the macrophage migration inhibition (MMI) assay were further characterized for their MMI response to diverse effectors as correlated with their Fc and C3b receptor function. MIF-refractory populations ...
Asada M - - 1983
Human lymphotoxin (LT)-producing T-cell hybridomas were constructed by fusing concanavalin A-activated human peripheral blood lymphocytes with emetine-actinomycin D-pretreated human acute lymphatic leukemia cells. LT secretion from these hybridomas was considerably enhanced by stimulation with phorbol-12-myristate-13-acetate (PMA) and concanavalin A or PMA alone. A study using cloned hybrid lines revealed that ...
Onozaki K - - 1983
The regulatory mechanism of guinea pig lymphokines was investigated in regard to differentiation of myeloid cells to macrophages. The Ml-cell line, established from a myeloid leukemia of an SL-strain mouse, was induced to differentiate in vitro into mature macrophages possessing Fc receptors and the ability to phagocytize latex particles by ...
Kimura Y - - 1983
Bradykinin, as well as histamine, one of the mediators in IgE mediated immediate type allergic reactions or acute inflammation, may affect the in vitro and in vivo cell-mediated immune reactions of the immunized animals. It was demonstrated in our present experiment that the appearance of delayed type hypersensitivity (DTH) skin ...
Kahlich R - - 1983
A prospective study involving 20 volunteers was designed to test relationships between the sensitivity to zymosan and the indicators of nonspecific immunity against streptococci (inhibitory activity of blood and production of mediators). The immunization with Mannozym produced a conversion of zymosan-induced MIF with a subsequent improvement of immunity indicators in ...
Mazzone T - - 1982
Regulation of the macrophage receptor for modified low density lipoprotein (LDL) was evaluated using human monocyte-derived macrophages and acetyl LDL. Factors that regulate native LDL receptor activity in other cell types, such as the cholesterol content of the incubation medium, insulin, and platelet-derived growth factor had no effect on acetyl ...
Evans C H - - 1982
Biphasic modulation of the frequency of 3-methylcholanthrene-induced tumors in relation to increasing immunocompetence of tumor-bearing mice is indicative of lymphoresponsive stimulatory and inhibitory phases of carcinogenesis; components and mechanisms contributing to the paradoxical ability of the native or natural immune system to stimulate as well as to inhibit the development ...
Sud I J - - 1982
In Staphylococcus aureus, using the imidazoles miconazole and ketoconazole, detailed studies of minimal inhibitory concentrations, kinetics of growth, viability, and release of intracellular K+ confirm that the two imidazoles work differently in this bacterium. Miconazole is bactericidal at low concentrations and causes release of cellular K+. Ketoconazole has no bactericidal ...
Polack F M - - 1982
Leukocyte migration inhibition factor (LMIF) assays have been used as a measure of cell-mediated immune responses. Direct assays of this factor were determined in 30 patients with recurrent herpes simplex stromal keratitis during the quiescent stage of the disease and in 10 of these patients during the acute stage as ...
Sorg C - - 1982
Macrophage migration inhibitory factors (MIFs) of mouse and guinea pig have been thoroughly characterized with regard to molecular weight and isoelectric points. Several molecular weight species have been identified. In a comparative study with purified MIFs it was found that these molecules were distinct from a series of other lymphokines, ...
Livni E - - 1982
Macrophage migration inhibition factor (MIF) towards autologous seminal fluid was studied in 29 infertile men, 16 of whom were also examined towards normal seminal fluid. In 10 patients, inhibition of macrophage migration was observed in the presence of 50 microgram of protein of autologous semen sonicates. Nine patients had enhanced ...
Sukhtankar A Y - - 1982
Evaluation of cellular immunity in burns was undertaken using the following parameters: T-cell count; blastoid transformation and macrophage migration inhibition factor index (MIF). Their influence upon bactericidal index was also measured as T-cell count per mm3 and in percentage was found to be depressed in parallel, probably due to some ...
Kahlich R - - 1982
Exoproducts of incubated white blood elements from persons hypersensitive to zymosan were found to promote the phagocytic activity of human microphages (and guinea pig macrophages) under conditions of a combined model of "MIF-opsonophagocytic test". The stimulation resulted in a bacteriostatic effect, was non-type-specific and improved microphage potential to inactivate streptococci ...
Bendtzen K - - 1982
The mechanism of action of the immunosuppressive drug, cyclosporin A (CyA), was analyzed with respect to antigen-induced production of the human lymphokine, leukocyte migration inhibitory factor (LIF). Mononuclear cells as well as purified T-cells did not elaborate LIF in the presence of pharmacological concentrations of CyA. CyA-induced immunosuppression was competitively ...
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