Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43026 (lipopolysaccharide)
 62,215 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The antitumour alkaloids, berberine and coralyne were investigated in terms of their ability to induce chemiluminescent responses and cytostatic activity in macrophages against tumour cells in vitro. Berberine hydrochloride and sulfate, and coralyne chloride, which had no direct tumoristatic activities at a concentration of less than 0.15 micrograms/ml, activated macrophages to inhibit the incorporation of tritiated thymidine into EL4 leukemic cells. The activation of cytostatic macrophages by berberine was not augmented by the addition of a suboptimal dose of macrophage activating factor (MAF). Furthermore, a marked chemiluminescent response of macrophages was induced by treatment with berberine as well as with MAF or lipopolysaccharide. These results show that berberine and coralyne are potent macrophage activators for inducing cytostatic activity against tumour cells in vitro.
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PMID:Activation of peritoneal macrophages by berberine-type alkaloids in terms of induction of cytostatic activity. 639 20

After 3-5 days of in vitro culture, peritoneal cells from untreated C3H mice produce autoantibodies specific for autoantigens in the membranes of mouse erythrocytes. The autoantigens are exposed in vitro by treating mouse erythrocytes with the proteolytic enzyme bromelain. Limiting-dilution cell culture techniques were used to determine the frequency of the autoreactive B cells. Cells were cultured in Terasaki trays at 10-200 cells/well. Autoantibody production was assayed with an in situ plaque-forming cell (PFC) assay. On average, one autoantibody precursor cell was detected for every 150-200 peritoneal cells cultured. This precursor frequency was increased to 1 in 50 by the addition of lipopolysaccharide (LPS) and dextran sulphate (DS) to the culture medium. The addition of a culture supernatant from an EL4 lymphoma subline also induced a high proportion of the peritoneal cells to secrete autoantibodies. However, it was not possible to determine the frequency of PFC accurately because at limiting numbers of peritoneal cells the effects of EL4 affected more than one limiting variable. Significant cell division was observed in cultures to which LPS/DS had been added, in contrast to untreated cultures to which EL4 supernatant was added. The results show that high numbers of autoreactive B cells committed to self antigens are present in the peritoneal cavity and that these cells under the influence of appropriate cytokines can differentiate in vitro, even without proliferation, into autoantibody secretors. The cell type or types releasing the cytokines remain to be identified.
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PMID:Peritoneal B cells differentiate without proliferation into autoantibody secretors under the influence of factors released by other cells. 639 20

Over a wide range of concentrations affinity-purified rabbit anti-mouse mu chain antibodies, or their F(ab')2 fragments, inhibit the appearance of immunoglobulin-secreting cells (plaque-forming cells; PFC) in lipopolysaccharide-stimulated murine spleen cell cultures without affecting proliferation. Both IgM and IgG PFC are inhibited although the number of blasts bearing surface IgG remains unaltered. The IgM and IgG PFC response could be reconstituted to normal levels in cell cultures suppressed by mu-specific antibodies by the addition of supernatants from in vitro propagated helper T cell clones, or from EL4 lymphoma cells induced with phorbol ester. Interleukin 1-containing P388 supernatant, or recombinant DNA-derived murine interferon-gamma, did not reconstitute the PFC response in cell cultures suppressed by mu-specific antibodies, indicating that other factors are responsible for these effects. When spleen cell cultures, pre-activated with either lipopolysaccharide or monoclonal mouse mu-specific antibodies coupled to Sepharose, were exposed to EL4 supernatants in the presence of soluble mu-specific antibodies, maturation to secretion was inhibited while proliferation was not. The implications of these findings on assay systems for B cell growth and maturation factors are discussed.
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PMID:Effects of mu-specific antibodies on B cell growth and maturation. 643 43

Murine lymphocytes were activated in vitro in mixed lymphocyte cultures (MLC) or by the addition of the mitogens concanavalin A (Con A), phytohemagglutinin (PHA), or E. coli lipopolysaccharide (LPS). Activated lymphocytes were internally labeled with 35S-methionine and then disrupted by hypotonic lysis. A plasma membrane-enriched fraction was isolated from each cell population, and the 35S-labeled proteins in this fraction were examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE). An intensely labeled band, the position of which indicated an apparent m.w. of 11,000, was observed when plasma membrane-enriched fractions from MLC- and Con A-activated cells were subjected to SDS-PAGE. In contrast, plasma membrane-enriched fractions from normal spleen cells, LPS-activated cells, PHA-activated cells, and EL4, RDM4, and P815 tumor cells possessed little or none of this protein, which we have designated T11. T11 was not found in the soluble cytoplasmic protein from MLC-activated cells. Hence the presence of T11 in the plasma membrane-enriched fraction from these cells cannot be attributed to contamination by cytoplasmic protein. Removal of T cells from populations of MLC-activated cells by treatment with monoclonal anti-Thy 1 and complement removed T11. These results suggest that T11 may represent a new protein marker on a subclass of activated T lymphocytes.
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PMID:T11: a new protein marker on activated murine T lymphocytes. 645 Feb 49

Nonspecific suppressor cells were induced during in vitro culture of normal mouse spleen cells (SPC) using the Marbrook culture system. The suppressor cells inhibited both the primary and secondary antibody-formation responses antigen nonspecifically in vitro, and both IgM- and IgG-responses were inhibited. The supernatants from suppressive precultured cells were not suppressive. The suppressor cells also inhibited the response of allogeneic SPC beyond H-2 compatibility. The induction of the suppressor cells did not require the presence of antigen but required fetal calf serum (FCS) or both FCS and 2-mercaptoethanol (2-ME). The suppressor cells were generated from the nylon-wool adherent, radiation-sensitive T cell population. On the other hand, the suppressor cells were nylon-wool nonadherent, relatively radiation-sensitive T cells. Actively antibody-producing cells were not affected by the suppressor cells. The suppressor cells inhibited the mitogenic responses of normal SPC to phytohemagglutinin-P (PHA), bacterial lipopolysaccharide (LPS) and concanavalin A (Con A). The suppressor cells themselves inhibited the growth of EL4 cells (T-cell leukemia of C57BL/6 mouse origin) and MOPCll cells (B cells, plasmacytoma of BALB/c mouse origin) even at a low effector-to target cell ratio (E:T ratio = 1:1), but did not kill these tumor cells. These results indicate that the target cells of the suppressor cells are both T and B cells, and that the mechanism of action of the suppression is either inhibition of proliferation or inhibition of early events in the course of the immune response.
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PMID:Spontaneously induced suppressor cells in vitro: nonspecific suppression of in vitro antibody formation. 646 Jan 59

Mouse thymocytes and spleen cells from unprimed C57BL/6 donors generate broadly reactive cytotoxic cells during 5 days of culture in vitro with polyinosinic acid (5') (poly(I] and/or supernatant from PMA-treated EL4 leukemia cells which contains interleukin 2 (IL-2) activity. We refer here to such cytotoxic cells as "supplement-induced cytotoxic cells" or SICC. Thymocytes are dependent on the supernatant factor(s), whereas spleen cells are usually stimulated by poly(I) alone. Polyinosinic acid acts synergistically with supernatant factor(s) to stimulate generation of SICC by both thymocytes (SICC-T) and spleen cells (SICC-S) when the IL-2 activity of the supernatant is inadequate alone. SICC can be generated by both splenocytes and thymocytes in medium supplemented with fetal calf serum or syngeneic plasma. SICC are active in 4 hr 51Cr-release tests against syngeneic, allogeneic, and xenogeneic tumors but not against lipopolysaccharide-induced lymphoblasts. Embryonic fibroblasts, too, are sensitive to SICC generated by thymocytes. In complement-dependent depletion tests, cytotoxic activity is partially sensitive (SICC-T) or fully sensitive (SICC-S) to anti-Thy-1 and -H-2 but not to anti-Lyt-1, -Lyt-2, or -asialo GM1.
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PMID:Supplement-induced cytotoxic cells (SICC) generated from mouse thymus or spleen cells cultured in the presence of interleukin 2 and/or polyinosinic acid. 660 5

Four types of macrophage activities were studied in sarcoma 180-bearing ICR mice and EL4-bearing C57BL mice. Sarcoma 180 cells grow very slowly and do not metastasize, while EL4 cells grow very rapidly and metastasize rapidly to the liver. Chemotactic activity of macrophages was significantly reduced from an early stage in both sarcoma 180-bearing ICR mice and EL4-bearing C57BL mice as compared with that in normal mice. Digestive activity, which was determined by following O2- production by chemiluminescence measurements was also reduced from an early stage in tumor-bearing mice, whereas no reduction of engulfment activity of microorganisms was observed until an advanced stage in both sarcoma 180-bearing mice and EL4-bearing mice. In contrast enhancement activity of macrophages in the blastogenic response of spleen lymphocytes to bacterial lipopolysaccharide was retained at the normal level at the early stage of the tumor graft and was reduced in later stages. These results suggest that activities of Ia-negative macrophages were at first depressed generally in tumor-bearing hosts and later the activities of Ia-positive macrophages were depressed by factor(s) which might be produced by tumor cells.
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PMID:Macrophage activities in sarcoma 180-bearing mice and EL4-bearing mice. 674 90

Cytotoxic hybridomas were generated by polyethylene glycol-induced fusion of cytotoxic T lymphocytes (CTL) and BW5147 lymphoma cells. The CTL populations used for fusion were obtained from BALB/c (H-2d) mice primed with leukemia EL4 of C57BL/6 (H-2b) and restimulated either in vivo or in vitro. To circumvent possible CTL-mediated nonspecific lysis of BW5147 cells during fusion, the CTL were transiently inactivated by trypsin prior to fusion. Four cytolytically active hybridomas were obtained, cloned, and subcloned. Hybrid clones lysed all H-2b leukemic target cells tested but not lipopolysaccharide- or concavanalin A-stimulated C57BL/6 lymphoblasts or non-H2b target tumor cells. The mechanism of hybridoma-mediated killing of target cells in vitro appears to be similar to that of parental CTL, although some differences have been observed. The hybridomas appear to possess neither natural killing nor antibody-dependent cytolytic activity. Clones of hybrids propagated in culture for over 6 months without the addition of known external stimulus (i.e., independent of cell growth factor and antigen) exhibit specific lytic activity against H-2b tumor cells. Such autonomous hybridomas will provide a tool for studying the mechanism of CTL-mediated lysis and the nature of the CTL receptors.
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PMID:Cytotoxic T lymphocyte hybridomas that mediate specific tumor-cell lysis in vitro. 697 38

A special class of immunologic cells can lyse or damage a variety of target cells, notably malignant cells in vitro. These cells have been called natural killer (NK) cells because lysis does not require deliberate immunization by tumor cells. Although these cells can be distinguished from conventional T cells, B cells, and phagocytic cells, they have been difficult to define. We describe a representative cloned cell line that was obtained by cloning Ig -Ly-5+ cells from spleen. This clone, Cl.Ly-1-2-NK-1+/11, displays Thy-1, Ly-5, Qat-4, Qat-5 and NK-1 cell surface antigens and lyses the NK-sensitive YAC-1 lymphoma cells, but does not lyse RL-12 cells, an NK-resistant lymphoma. In addition, this clone lysed the P815 mastocytoma, EL4 lymphoma, and lipopolysaccharide-activated B lymphocyte targets. This cloned population therefore combined information for a unique display of cell surface antigens and specialized function similar to "activated" NK cells. Because this cloned population forms conjugates with susceptible but not resistant target cells, it may prove useful to identify the structure of cell surface molecules that recognize foreign cells. Finally, cells of this clone also specificity lysed target cells coated by antibodies to determinants on the target cell surface, demonstrating that a single cloned cell population can mediate two specialized immunologic functions: antibody-dependent cellular cytotoxicity and NK cell lysis.
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PMID:Multiple activities of a cloned cell line mediating natural killer cell function. 697 1

A relatively large population of murine peritoneal exudate macrophages induced with viable BCG or heat-killed Corynebacterium parvum was stained by the antiserum prepared against purified gangliotetraosyl ceramide (asialo GM1), while only a small population of peritoneal resident macrophages or peritoneal exudate macrophages induced with proteose peptone was stained. The cytotoxicity assay of those macrophages with anti-asialo GM1 plus complement supported these results. Peritoneal macrophages induced with BCG or C. parvum showed strong cytotoxicity for EL4 cells in vitro, while resident or peptone-induced peritoneal macrophages showed no cytotoxicity. BCG- or C. parvum-induced peritoneal cells contained both NK cells and cytotoxic macrophages, and either in vivo or in vitro pretreatment of the cells with anti-asialo GM1 and complement abolished the activities of both types of cells. Peptone-induced peritoneal macrophages incubated with lymphokines (LK) or lipopolysaccharide (LPS) were cytotoxic for EL4 cells and contained an increased number of cells stained by anti-asialo GM1. The cytotoxicity of these in vitro activated macrophages was reduced by treatment with anti-asialo GM1 plus complement. When peptone-induced peritoneal macrophages were incubated with LK, the number of cells stained by anti-Ia antiserum increased, but the number did not increase when the macrophages were incubated with LPS. Pretreatment of peptone-induced macrophages with anti-asialo GM1 plus complement did not affect the ability of the macrophages to be activated by LK. These results taken together strongly suggest that the antigen(s) reactive with anti-asialo GM1 is expressed on the cell surface of cytotoxic peritoneal macrophages in mice.
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PMID:Appearance of a cell surface antigen associated with the activation of peritoneal macrophages in mice. 715 91


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