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)

Removal of adherent cells or complement-mediated killing of rabbit thymus lymphocyte antigen (BTLA) bearing rabbit T lymphocytes did not abolish the responsiveness (increased thymidine incorporation) of lymphoid cells to antibody against immunoglobulin allotype, Nocardia water-soluble mitogen (NWSM), pneumococcal polysaccharide SIII (PPSIII), S. abortus lipopolysaccharide (LPS), lipid A conjugated to bovine serum albumin and a crude preparation containing C polysaccharide from the cell wall of Diplococcus pneumoniae. Isologous and heterologous antisera, directed against different portions of the Ig receptor, differed in their capacity to enhance thymidine incorporation. The difference in mitogenicity of these antisera was discussed in terms of the accessibility of cell-bound immunoglobulin receptor sites. Spleen cells, responsive to anti-allotype (Ab4) antiserum and B-cell mitogens, NWSM and PPSIII, were characterized by velocity sedimentation. The mean volume of NWSM- and PPSIII-responsive cells was larger than that of the cells responsive to anti-allotype antiserum. Fractionation of spleen cells on glass bead columns yielded a population of non-adherent cells which were two to six times as responsive to anti-Ab4 antiserum as the original spleen cell suspension. The responsiveness of peripheral blood lymphocytes to anti-Ab4 antiserum was significantly greater than that of spleen cells. On the other hand, spleen cells were more responsive to PPSIII than were cells from the peripheral blood, the popliteal and the mesenteric lymph nodes.
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PMID:Rabbit lymphoid cells. II. Anti-allotype antisera, lipopolysaccharide and other bacterial and fungal mitogens as probes for the identification of B-cell subpopulations. 108 19

The activation of guinea pig peritoneal macrophages by Salmonella typhimurium lipopolysaccharide (LPS) was studied by using 14C-glucosamine uptake. Peritoneal exudate cells incorporated significant amounts of 14C-glucosamine when stimulated with LPS but neither purified macrophages nor nonadherent lymphocytes by themselves incorporated glucosamine. The activation of macrophages could be restored by adding nonadherent peritoneal lymphocytes, spleen cells, and lymph node cells but not thymocytes. Removal of B lymphocytes abolished the restorative capacity from active lymphoid cell populations. In contrast, B lymphocytes would restore glucosamine incorporation by macrophages stimulated with LPS but T lymphocytes did not. In addition, cell-free supernatants from LPS stimulated B lymphocytes but not from T lymphocytes could restore glucosamine incorporation by macrophages. These experiments demonstrate that LPS does not directly activate macrophages as measured by glucosamine incorporation but stimulates B lymphocytes which in turn activate macrophages.
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PMID:Activation of guinea pig macrophages by bacterial lipopolysaccharide requires bone marrow-derived lymphocytes. 109 Jun 57

Anti-rabbit thymocyte antibody can totally inhibit the induction of IgM production that ordinarily is observed whem lymphoid cells are incubated, in virto, in the absence of added antigen. Univalent as well as bivalent antithymocyte antibody preparations were inhibitory when added to cells before the induction of immunoglobulin production had occurred but not afterwards. Spleen cells that had been treated with antithymocyte antibody and then cultured with thymocytes for 72 hours exhibited an enhanced inducttion of immunoglobulin production. Untreated spleen cells also showed this property, although both untreated lymph node cells and lymph node cells treated with antithymocyte antiboyd did not respond to thymocytes. The enhancement of the induction of immunoglobulin production by lipopolysaccharide was found to be T-cell dependent as judged from studies using antithymocyte antibody.
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PMID:The absolute requirement for T-cells in the induction of IgM-secreting cells, in vitro. 109 73

Old (6 months) overtly autoimmune female NZB X NZW F1 (B/W) mice were markedly hyporesponsive to sheep erythrocytes (SRBC). The response to SRBC was restored by a) simultaneously injecting lipopolysaccharide (LPS) with SRBC or b) transferring bone marrow and thymocytes with SRBC into lethally x-irradiated (100 R) syngeneic old recipients. The in vitro PFC response of old B/W spleen cells to SRBC was restored by adding in culture a) theta-positive and radioresistant spleen cells from old B/W mice primed with homologous antigen or b) activated T cells from the spleens of lethally x-irradiated (1000 R) old B/W mice injected with old syngeneic thymocytes and SRBC but not horse erythrocytes. Various populations of unprimed lymphoid cells from young (4 to 6 weeks) female B/W mice, which respond normally to SRBC, were not capable of restoring the response of old syngeneic mice in vitro or in vivo. These results suggest the existence of a suppressor of T cell activation and/or B and T cell interaction in old autoimmune B/W mice.
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PMID:T cell activation and cellular cooperation in autoimmune NZB/NZW F hybrid mice. 109 16

In 4 to 24 hr cultures of rabbit lymphoid cells in medium supplemented with autologous serum, most B cells lost their surface Ig as assayed by rosette formation with anti-Ig antibody-coated erythrocytes. This loss was prevented by adding selected mitogens such as streptococcal mitogen (SM), lipopolysaccharide, and concanavalin A or by supplementing the medium with fetal calf serum. When SM was added at various times to the cultures (1, 2, 3, and 4 hr), it was effective in maintaining the approximate level of Ig-bearing cells present at the time of its addition but was ineffective in restoring the level of Ig-bearing cells present at the time the cultures were intiated. Very small, submitogenic doses of SM were sufficient to maintain the level of Ig-bearing cells. The data suggest that lymphocytes require continuous stimulation to maintain their surface receptors.
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PMID:Maintenance of lymphocyte surface Ig by mitogen stimulation in vitro. 118 68

Inbred animals (Lewis rats) were used to investigate the regeneration of autologously implanted splenic tissue at intra-omental and subcutaneous sites. Quantitative immunohistology with monoclonal antibodies against lymphocytes and macrophages was performed to analyse the cell density of red pulp (RP), periarteriolar lymphoid sheath (PALS), marginal zone (MZ) and follicle, 7-180 days after transplantation. Antigenic, allogeneic and mitogenic stimulation and Northern blotting were also performed. Transplant groups differed from spleen only in the reduced size of PALS; however, quantitative analysis demonstrated subtle differences between spleen and transplants. The cell density of B-cells and ED-1+ macrophages was reduced in the RP, Tsupp/cyt-cells were decreased and B-cells increased in PALS, and B-cells and Thelper-cells reduced in the MZ. No differences could be detected between the transplant groups. Flow-cytometric analysis of cell suspensions from spleen and transplants revealed a reduction of T-cells (OX-19+), MHC-I and transferrin-receptor-bearing cells in both transplant groups, and a decrease in the number of Thelper-cells and ED-3+ macrophages in subcutaneous transplants. Both transplant groups were defective regarding the allogeneic and pokeweed mitogen response. Aberration of the lipopolysaccharide response was restricted to subcutaneous transplants, which additionally showed abnormal expression of interferon-gamma, interleukin-5 and interleukin-6 mRNA. Thus, subtle alterations of the newly developed microenvironment and/or lymphocyte-homing may influence the regeneration of splenic tissue; the implantation site may represent an important parameter in functional reorganisation.
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PMID:Regeneration of autotransplanted splenic tissue at different implantation sites. 133 Mar 13

We have investigated the regulation of transforming growth factor beta 1 gene expression in a variety of porcine immune cell populations, including peripheral blood mononuclear cells (PBMC), peripheral blood monocytes, alveolar macrophages and lymphoid cells from various swine lymphoid tissues. Using porcine transforming growth factor beta 1 cDNA probes in Northern blot assays, messages of 2.5 and 3.5 kb TGF beta 1 mRNA were detected in the cells investigated. A variety of mitogenic and immunomodulatory substances were examined for their ability to induce TGF beta 1 mRNA expression. These include phorbol 12-myristate 13-acetate (PMA), phytohemagglutinin (PHA), concanavalin A (Con A), lipopolysaccharide (LPS), dexamethasone (Dex), tumor necrosis factor (TNF) and interleukin (IL)-1 alpha. While low level constitutive expression of TGF beta 1 mRNA was detected from all cells investigated, PMA treatment of PBMC and alveolar macrophages resulted in a more than 10-fold increase in the steady-state level of TGF beta 1 mRNA within 2 hr of PMA addition. Also, the effect of opiate drugs, methadone (Md) and morphine (Mor), on TGF beta 1 gene expression was determined. Cells treated with opiates expressed the same levels of TGF beta 1 mRNA as untreated cells. Since TGF beta 1 biological activity can be induced by opiates, the regulation of TGF beta 1 gene expression likely involves mechanisms that do not cause changes in mRNA levels.
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PMID:Characterization of transforming growth factor-beta 1 gene expression in porcine immune cells. 138 43

Endothelial cell activation antigens may play important roles in immune responses and in inflammation. This report describes the identification and characterization of a monoclonal antibody, named EAA-B, which reacts specifically with human umbilical vein endothelial (HUVE) cells pre-treated with tumour necrosis factor-alpha (TNF-alpha) but not with untreated cells. The expression of the EAA-B antigen on HUVE cells could also be induced by interleukin-1 (IL-1), bacterial lipopolysaccharide (LPS), and phorbol esters but not by interferon-gamma (IFN-gamma). By contrast, EAA-B antigen expression on neonatal foreskin and rheumatoid synovial fibroblasts, whether pre-treated with TNF-alpha or not, was not detectable. Peripheral blood leucocytes and the leukaemic cell lines U937, HL-60, Raji and Molt 4 showed no detectable expression of the EAA-B antigen. Kinetic studies demonstrated that the EAA-B antigen was rapidly expressed, peaked at 6 hr and declined to basal level by 24 hr. Western blotting revealed that monoclonal antibody EAA-B recognized a polypeptide of approximately 80,000-90,000 MW. EAA-B partially blocked the augmented adhesion of HL-60 cells to TNF-treated HUVE cells. However, it failed to inhibit the enhanced binding of peripheral blood leucocytes, U937, Raji and Molt 4 Cells to TNF-treated HUVE cells. In situ, the EAA-B antigen was detected on some vascular endothelium in tonsils, lymph nodes, psoriatic skin and rheumatoid synovium but not in normal non-lymphoid tissues. Interestingly EAA-B antigen is also expressed by B lymphocytes in germinal follicle centres (GFC) of lymphoid tissues. The co-expression of this endothelial activation antigen by GFC B lymphocytes may have significant implications for immune responses and in B-lymphocyte differentiation.
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PMID:Identification of a human endothelial cell activation antigen that is co-expressed by germinal follicle centre B lymphocytes. 139 50

The phenotypes and functions of various populations of non-lymphoid cells in the chicken spleen were investigated with monoclonal antibodies and after in vivo administration of antigens. Monoclonal antibody CVI-ChNL-68.1 was used to detect red pulp macrophages, interdigitating cells, and monocytes, whereas CVI-ChNL-68.2 was used to detect ellipsoid-associated non-lymphoid cells (EANC). Two new monoclonal antibodies were developed: CVI-ChNL-74.2, which specifically recognized red pulp macrophages and a ring of macrophages surrounding the peri-ellipsoid lymphocyte sheath; and CVI-ChNL-74.3, which specifically recognized follicular dendritic cells (FDC) in germinal centres and small clusters of stromal cells in T-cell areas. After intravenous injection of lipopolysaccharide (LPS), the number of 68.1+ and 74.2+ macrophages decreased dramatically, whereas 68.2+ EANC and 74.3+ FDC were unaffected. After intravenous injection of heat-inactivated Brucella abortus, the numbers of both macrophages and EANC decreased. In contrast, a significant increase of 74.3+ cells was observed in the T-cell areas outside the germinal centres. As expected, intravenous injection of non-mitogenic antigens, such as keyhole limpet haemocyanin and Ficoll, and carrageenan did not affect the non-lymphoid cell populations. At least six subpopulations of non-lymphoid cells in the chicken spleen can now be discriminated with monoclonal antibodies. Our results show that mononuclear phagocytes are sensitive for mitogenic stimulators such as LPS and Brucella abortus. In contrast, stromal non-lymphoid cells are only sensitive to the particulate mitogen Brucella abortus. We conclude that the complex formed by ellipsoid cells, the peri-ellipsoid B-cell sheath, and the surrounding macrophages, is the functional equivalent of the mammalian marginal zone.
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PMID:Histological and functional differentiation of non-lymphoid cells in the chicken spleen. 139 67

A series of immunoglobulin (Ig)-transgenic mice were generated to study the functional capabilities of the IgM and IgD classes of B lymphocyte antigen receptor in regulating both cellular development and responses to specific antigen. B cells from Ig-transgenic mice expressing either hen-egg lysozyme (HEL)-specific IgM or IgD alone were compared with B cells from mice that coexpressed IgM and IgD of the same anti-HEL specificity. In all three types of Ig-transgenic mice, conventional B cells specific for HEL exhibited exclusion of endogenous Ig expression and matured to populate the usual microenvironments in peripheral lymphoid tissues. These peripheral B cells could be stimulated by HEL through either IgM or IgD antigen receptors to generate T cell dependent antibody production in vivo or to enhance T cell independent proliferative responses to lipopolysaccharide in vitro. Conversely, when HEL was encountered in vivo as a self-antigen, B cells expressing HEL-specific IgM or IgD alone were both rendered tolerant. In each case this occurred by clonal anergy in response to soluble autologous HEL, and clonal deletion when HEL was recognized as a membrane-bound self-antigen. Taken together, these findings indicate that IgM and IgD antigen receptors expressed alone on conventional B cells can support normal differentiation, antigen-dependent activation, and induction of self-tolerance, the only overt difference lying in a greater degree of receptor downregulation for IgM relative to IgD after induction of clonal anergy by soluble HEL.
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PMID:Immunoglobulin M and D antigen receptors are both capable of mediating B lymphocyte activation, deletion, or anergy after interaction with specific antigen. 140 69


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