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

Spleen and lymph node cells from DBA/2 (H-2d) donor mice treated with multiple injections of bacterial lipopolysaccharide (LPS) were tested in vivo for reactivity against normal tissues of host AKR (H-2k) mice against an AKR long-passage, acute lymphoblastic leukemia (BW5147). LPS treatment of donor mice resulted in a reduction in graft-versus-host (GVH) reactivity without loss of graft-versus-leukemia (GVL) reactivity. Immunocompetent cells from LPS treated DBA/2 donors were effective when used for adoptive immunotherapy (in combination with chemoradiotherapy) of BW5147 leukemia. GVH associated mortality decreased as the dose of spleen cells from LPS treated histoincompatible donors was increased as much as four times the number necessary to eliminate leukemia. The mechanism by which LPS reduced GVH reactivity without eliminating GVL reactivity is unclear; however, it does not appear to be the result of a dilution in the number of GVH reactive cells by nonlymphoid elements in the donor spleen nor of the adjuvant effects of LPS on resistance to bacterial infections.
 ...
PMID:Graft versus leukemia. VIII. Selective reduction in antihost reactivity without loss of antileukemic reactivity by treatment of donor mice with lipopolysaccharide. 2 84

The X-chromosome-linked B lymphocyte defect of CBA/N mice has been studied in vitro by comparing the ability of (CBA/N X DBA/2)F1 (X-/X- X X+/Y) male (X-/Y) and female (X-/X+) spleen cells to respond to the thymus-independent antigen DNP (or TNP)-AECM-Ficoll. (CBA/N X DBA/2)F1 male spleen cells failed to generate significant in vitro anti-TNP antibody responses to DNP- or TNP-AECM-Ficoll, in contrast to spleen cells from F1 female (X-/X+) mice which responded normally to these T-independent antigens. Spleen cells from male F1 mice responded almost as well as F1 female cells to the thymus-dependent antigen, TNP-sheep red blood cells (TNP-SRBC) in vitro. Adding F1 male cells to F1 female cells failed to reduce the response of the latter to DNP-AECM-Ficoll, suggesting that the inability of F1 male cells to respond was not due to active suppression. The response of F1 male spleen cells to TNP-SRBC was not impaired by adding high concentrations of TNP-AECM-Ficoll indicating that the mechanism of unresponsiveness was not tolerance induction in all TNP-specific precursors. Lymphocytes from F1 male mice were capable of forming anti-TNP antibody after stimulation with lipopolysaccharide (LPS) in high concentrations; DNP-AECM-Ficoll had no effect on this polyclonal response. B lymphocytes from mice bearing only the X-chromosome of the CBA/N strain thus display a profound defect in B cell activation. This functional defect may represent either an inability of the defective B cells to be activated by thymus-independent antigens or the absence of a sub-class of B cells which respond to thymus-independent antigens.
 ...
PMID:In vitro studies of the genetically determined unresponsiveness to thymus-independent antigens in CBA/N mice. 5 35

Thymus of (C57Bl/6 x DBA/2) F1 mice was examined histologically, histochemically and ultrastructurally, seven days after intravenous injection of BCG, pertussis vaccine, lipopolysaccharide or human gamma globulin, or intraperitoneal injection of complete or incomplete Freund's adjuvants or of phytohemagglutinin. Only BCG induced a marked increase of the secretory activity of the thymic epithelium at all histological sites (cortex, corticomedullary junction and medullar). Only with this adjuvant was the epithelial hyperplasia associated with marked mitotic activity and high percentage of cells with cytoplasmic pyroninophilia among cortical lymphoid cells. The other substances tested produced different changes in the thymic epithelial cells according to the histologic zones. These results suggest that the epithelial cells of the cortex, the corticomedullary junction and the medulla respond differently to the agents tested and that the action of these substances upon thymus-dependent lymphoid cells may be indirect perhaps involving factors secreted by the epithelial cells.
 ...
PMID:The effects of certain immunity systemic advuvants, PHA, and human gamma globulin on the thymic cortex of mice: a light and electron microscope study. 6 71

CBA/N mice have an X-linked immune defect in B lymphocyte function which leads to their inability to respond to several thymus-independent antigens. We report here that these mice and immunologically defective F1 male (CBA/N X DBA/2N) mice can respond to Brucella abortus and to 2,4,6-trinitrophenyl derivatives of Brucella abortus (TNP-BA). These responses can be obtained in vivo and in vitro and are thymus-independent by the criteria that (a) they can be transferred to irradiated recipients by bone marrow cells and anti-Thy-1.2 and complement-treated spleen cells; (b) that nu/nu BALB/c spleen cells respond to TNP-BA in vitro; and (c) that anti-Thy-1.2 and complement-treated (CBA/N X DBA/2N)F1 male spleen cells respond to TNP-BA in vitro. B. abortus and TNP-BA are poor polyclonal B cell activators (PBA) and poor B cell mitogens, unlike lipopolysaccharide which is both a powerful PBA and B cell mitogen. These results therefore indicate that mice with the CBA/N B cell defect can respond to some thymus-independent antigens, namely TNP-BA, and as shown previously, TNP-LPS, although not to other thymus-independent antigens. This, in turn, suggests that thymus-independent antigens may be subdivided on the basis of their ability or inability to stimulate responses by CBA/N B lymphocytes.
 ...
PMID:T-independent responses in B cell-defective CBA/N mice to Brucella abortus and to trinitrophenyl (TNP) conjugates of Brucella abortus. 9 20

The mitogens concanavalin A (Con A) and bacterial lipopolysaccharide (LPS) stimulated normal spleen cells of DBA/2J, CBA/J, and BALB/c mice about equally in the presence of either isologous or homologous serum. This system revealed that sera from mice with five different methylcholanthrene-induced rhabdomyosarcomas inhibited mitogen stimulation of normal spleen cells. Sera from mice with a mammaryadenocarcinoma and spontaneous rhabdomyosarcoma were similarly suppressive. In contrast, sera from mice with melanoma were not inhibitory and often enhanced stimulation. Sera from tumor-bearing animals had the same effects both qualitatively and quantitatively on cells from the strain carrying the tumor and on cells from the other two strains. The mixed lymphocyte response of CBA/J times BALB/c spleen cells was affected exactly as were the responses to mitogen by the various sera. Stimulation by mitogen of mouse lymph-node cells and spleen cells with macrophages removed, as well as that of guinea pig spleen cells, was also inhibited by sera from mice with rhabdomyosarcoma and mammary adenocarcinoma.
 ...
PMID:Effects of sera from tumor-bearing mice on mitogen and allogeneic cell stimulation of normal lymphoid cells. 12 99

Spleen cells removed from C57Bl/6J mice bearing a methylcholanthrene-induced fibrosarcoma (MC-16) demonstrate suppressed responsiveness of phytohemagglutinin (PHA) and bacterial lipopolysaccharide (LPS) induced mitogenesis as compared to non-tumorous mice. A similar depression of PHA-induced mitogenesis was observed with spleen cells from C3H/HeJ mice bearing syngeneic mammary adenocarcinomas (C3HBA). The administration of indomethacin, a non-competitive irreversible prostaglandin (Pg) synthesis inhibitor, (75 or 100 mug/mouse, IP) on an alternate day basis to groups of tumor-bearing mice of both strains, significantly enhanced immune cell responsiveness to mitogenic stimulation. The addition of indomethacin (10 mug/ml) to cultures of spleen cells from these tumor-bearing mice, as well as to DBA/1J mice bearing the Cloudman S-91 melanoma, enhanced spleen-cell responsiveness to mitogen-induced DNA synthesis by as much as 156%. Indomethacin administration in vivo or in vitro had no significant effect on mitogen-induced DNA synthesis of spleen cells from non-tumor-bearing animals. It is hypothesized that tumors, or tumor-cell antigens, increase Pg production of a population of spleen cells, and that the increased Pg content of the spleen may be important in controlling immune responsiveness in mice.
 ...
PMID:Indomethacin enhancement of spleen-cell responsiveness to mitogen stimulation in tumorous mice. 18 13

Plaque-forming cell responses against sheep erythrocytes, Escherichia coli lipopolysaccharide, pneumococcal polysaccharide, and polyvinylpyrrolidone were examined in mice infected with lymphocytic choriomeningitis virus. A 92 to 96 percent reduction of the thymus-dependent anti-sheep erythrocyte responses was observed 2 to 4 weeks after infection. However, the thymus-independent responses against the three other antigens were close to normal at all stages of the infetion. Studies on allograft immunity of infected C3H mice against DBA/2 mastocytoma cells revealed a severe suppression of the T cell-mediated cytotoxic response which was temporally related to the impaired humoral responsiveness against sheep erythrocytes. The capacity of spleen cells from infected mice to restore immune responsiveness of lethally irradiated recipients against sheep erythrocytes was significantly reduced. The adoptive responses, however, were clearly improved when normal thymus cells were added to the inferior spleen cells. Moreover, it appeared that the spleen cells from immunosuppressed donor mice could not confer suppression to normal lymphoid cells. The presented findings are consistent with the assumption that a numeric deficiency of T cells, or cells belonging to some T cell subpopulation, is the primary cause of lymphocytic choriomeningitis virus-induced immunosuppression.
 ...
PMID:T lymphocyte function as the principal target of lymphocytic choriomeningitis virus-induced immunosuppression. 23 88

The immune response of mice to the alpha-l-6 epitope of dextran (Dx) B512 was found to be under genetic control. The congenic mouse strains A, A.CA, A.SW, A.TH, and A.TL exhibited a specific defect in their response to alpha-l-6. Also strain CBA/N was unresponsive to alpha-1-6, but the mechanism of unresponsiveness was found to be different. Unresponsiveness to alpha-l-6 in congenic A strains was not due to suppressor cells. Although these strains failed to respond to the alpha-l-6 epitope, they responded strongly to the hapten Fluorescein isothiocyanate (FITC) conjugated to Dx, indicating that the Dx can function as an efficient carrier in these strains. Dx was a potent polyclonal B-cell activator in congenic A strains as well as in high responder strains. Polyclonally-activating concentrations of lipopolysaccharide (LPS) failed to induce the synthesis of anti-alpha- l-6 antibodies in congenic A strains, although antibodies of all other specificities studied were produced. However, in high responder strains, LPS induced the synthesis of anti-alpha-l-6 antibodies. It was concluded that congenic A strains do not express V genes coding for antibodies against alpha-l-6. In contrast, strain CBA/N failed to respond to both the alpha-l-6 and FITC epitope on Dx, whereas they could respond to FITC conjugated to horse erythrocytes. Dx induced a very small, if any, polyclonal antibody response in B cells from CBA/N mice or male CBA/N x DBA hybrids, whereas Dx was a very potent polyclonal B-cell activator in female hybrids. It is concluded that CBA/N mice are nonresponders to Dx or haptenated Dx, because the cell population that can respond to the polyclonal B-cell activating properties of Dx is severely depleted.
 ...
PMID:Immunological unresponsiveness to thymus-independent antigens: two fundamentally different genetic mechanisms of B-cell unresponsiveness to dextran. 30 86

The effect of age on the mitogenic and antigenic responsiveness of B cells is examined in spleen cell cultures of CBA/N and (CBA/N X DBA/2) F1 mice. Spleen cells from young male F1 mice (4- to 6-wk old) show lower mitogenic responses to lipopolysaccharide, a lower frequency of sheep erythrocytes (SRBC)-reactive B-cell precursors, and a lower percentage of Ig-bearing cells than age-matched female F1 mice. The expression of all three functions were found to increase with the age of the F1 male mice. Whereas male F1 mice at 60 wk of age showed an equivalent percentage of Ig-bearing spleen cells and a similar mitogenic responsiveness to LPS when compared to adult female F1 mice, the frequency of SRBC-reactive B-cell precursors remained threefold lower. These findings reveal that there is a slower maturation of B cells in mice expressing the X-linked defect and suggests that the defect has differential effects on the mechanisms of antigen and mitogen activation of B cells.
 ...
PMID:B-cell differentiation in the CBA/N mouse. I. Slower maturation of mitogen and antigen-responsive B cells in mice expressing an X-linked defect. 31 94

Combinations of delta 9-tetrahydrocannabinol (delta 9-THC) and bacterial endotoxin were shown to be hyperadditively toxic for mice. A variety of purified lipopolysaccharide (LPS) preparations elicted enhanced mortality in combination with delta 9-THC. Escherichia coli O26:B6 LPS (Boivin preparation) at an essentially nonlethal dose of 2.5 mg/kg reduced the dose of delta 9-THC required to kill 50% of the treated mice from ca. 350 to 150 mg/kg. Inbred BALB, DBA, and C3H/HeCr mice, noninbred ICR mice, and hybrid CDF1 and BDF1 mice were hyperreactive to combinations of delta 9-THC and LPS. Moreover, a variety of heat-killed intestinal and gram-negative bacteria, live E. coli, and complexes of lipid A with a variety of proteins substituted for LPS in the synergistic toxicity of LPS and delta 9-THC. Extracts of marijuana also elicited hyperreactivity to LPS. The hyperadditive lethality of combinations of delta 9-THC and LPS was markedly less in mice rendered refractory to LPS or delta 9-THC by repeated administration of LPS or delta 9-THC, respectively.
 ...
PMID:Enhanced susceptibility of mice to combinations of delta 9-tetrahydrocannabinol and live or killed gram-negative bacteria. 33 Apr 5


1 2 3 4 5 6 7 8 9 10 Next >>