Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The immune response to a thymus-dependent antigen was depressed in vivo and in vitro in spleen cells from mice injected with LPS i.p. a few days before challenge with the antigen. Spleen cells from LPS-injected mice could, however, respond with increase DNA synthesis after activation with polyclonal B and T cell activators in vitro. The LPS-activated spleen cells could actively suppress normal cells in their response to the antigen sheep red blood cells. The suppressor cells contained in the LPS-activated spleens were most likely B lymphocytes, and the possible mechanism for their inhibitory function is discussed.
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PMID:Lipopolysaccharide-induced suppression of the primary immune response to a thymus-dependent antigen. 1 30

Spleen rosette forming cells (RFC) from adult thymectomized mice have a low sensitivity to inhibition by anitheta serum (AOS) and azathioprine (AZ) in comparison with normal spleen or thymus RFC. Thymus extracts and normal mouse serum (but not spleen extracts or thymectomized mouse serum) correct this abnormality after a 30 min in vitro incubation with spleen cells. We report here the existence of a serum factor produced in allogeneic reactions with the same activity on rosettes as thymic factor (TF). This 'allogeneic' factor (AF) is detectable in mice undergoing a graft versus host reaction (GVHR), rejecting skin allografts or allogeneic cells or responding to thymus-dependent antigens such as heterologous red blood cells or BSA. The T-cell origin of AF is indicated by AF presence in nude mice submitted to the same allogeneic stimuli as listed above and in normal mice injected with PVP or LPS. AF is distinct from the thymic factor as shown by differences in electric charge. Moreover, in contrast with TF there is no specific high molecular weight inhibitor of AF. Preliminary biochemical studies indicate that AF is probably a peptide of low molecular weight (greater than 5000 daltons). Its target cell is probably a T-cell precursor.
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PMID:Demonstration and characterization of a serum factor produced by activated T cells. 2 86

The effect of related and unrelated compounds on the specific binding of dinitrophenyl-coupled bacteriophage (DNP-T4) to lymphoid cell receptors has been examined and compared with the effect on the neutralization of DNP-T4 by anti-DNP serum. Spleen cells and sera from Balb/c mice immunized with DNP-bovine serum albumin were used. The binding of DNP-T4 to the cells was inhibited by DNP-eAcp, di-DNP-Lys, DNP-Tyr, DNP-p(Ornith) and DNP-BSA (among the DNP-derivatives tested), TNP-BSA, ARS-p(Tyr) and TGA. In addition with the above named DNP and TNP compounds, the DNP-T4neutralization by antiserum was also prevented by DNP-derivatives with either L-cysteic acid, alanine, glutamine or poly-L-glutamic acid, while ARS-p(Tyr) and TGA were not effective. Plain carriers (BSA, HSA, poly-ornithine, polylysine and polyglutaminc acid) and cell-mitogens (ConA, LPS and PPD) had no significant inhibitory effect. The results obtained indicate the occurrence of differences between cell-bound receptors and circulating antibodies in what concerning their specific reaction with the dinitrophenyl determinant.
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PMID:Inhibition of specific binding of DNP (dinitrophenyl) determinant to lymphoid-cell receptors by related and unrelated compounds : quantitative studies in vitro. 6 Sep 7

Concanavalin A induced polyclonal antibody synthesis in normal spleen cells in vitro. Optimal responses were obtained by Con A concentrations lower than those optimal for induction of DNA synthesis. T cells, but not macrophages, were necessary for the effect. Spleen cells from nude mice were not activated, whereas cells from the LPS non-responder stain C3H/HeJ were activated to polyclonal antibody synthesis by Con A. Supernatants from Con A activated spleen cells could by themselves induce polyclonal antibody synthesis in untreated spleen cell cultures, even when Con A had been removed by absorption with Sephadex G-50 and when alpha-methyl-mannoside was present in the secondary cultures. T cells produced the active supernatants, which were competent to induce polyclonal antibody synthesis, but not DNA synthesis, in both H-2-incompatible and compatible strains. When the supernants were absorbed with erythrocyte antigens, they specifically induced an enhanced response, in secondary cultures, to the antigen used for absorption. Possible mechanisms of this specific effect are discussed.
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PMID:Con-A-activated T cells secrete factors with polyclonal B-cell-activating properties. 8 58

The aim of this study was the identification of the cell type in which genes selected for high or low response to SRBC express their functions. Spleen cells from high (H) and low (L) responder mice were immunized with SRBC in the Mishell and Dutton system. An antibody response of different magnitude was found in cultures of H and L spleen cells, the difference being at least as great as that observed in vivo. This finding under experimental conditions allowing the exclusion of any influence of the animal milieu during the immune response, suggest macrophages, B, and T lymphocytes as possible target cells of gene action. In vitro cell separation and recombination experiments in which spleen cells were immunized with SRBC, TNP-LPS, or TNP-HRBC indicate that the genetic differences between H and L responders brought about by selective breeding are expressed in lymphocytes to greater extent than in macrophages. The role of histoincompatibility in the recombination experiments in unlikely but cannot be excluded. Among lymphocytes, B cells but not helper T cells were found more responsive in cultures of spleen cells from H than from L mice.
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PMID:In vitro immune response of spleen cells from mice genetically selected for high or low antibody production. 9 27

8-Br-cyclic GMP has been found to be a specific B cell mitogen; it triggers athymic nude mice spleen cells and "B mice" spleen cells, nylon adherent, anti-theta and complement-treated cells to proliferate. It does not stimulate thymocytes or purified T cells. The kinetics of the response to Br-cyclic GMP and LPS are almost identical. The mitogenic effect of LPS and Br-cyclic GMP is additive when the two mitogens are given together to cells. Spleen cells (C3H/HeJ strain) that did not respond to LPS were triggered by Br-cyclic GMP to make DNA. In order to achieve maximal stimulation by Br-cyclic GMP, the drug had to be in contact with the cells for more than 24 hr. Br-cyclic GMP was found to be mitogenic for spleen cells from five different mouse strains, but not for human leukocytes. DB-cyclic AMP was found to inhibit the DNA synthesis of T lymphocytes after they interacted with Con A; DB-cyclic AMP had no effect on the ability of the B lymphocytes to be transformed by LPS. The differential effects of cyclic nucleotides on B vs. T lymphocytes are discussed.
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PMID:Specific mitogenic activity of 8-Br-guanosine 3',5'-monophosphate (Br-cyclic GMP) on B lymphocytes. 16 53

Replication of HSV was demonstrated in spleen cell cultures of D2 and several other strains of mice after prestimulation with mitogenic doses of LPS for 2 days. No viral replication occurred in unstimulated cultures or in cultures prestimulated with PHA and Con A, whereas there was some viral replication in spleen cell cultures of D2 mice after prestimulation with Poly I-C. Spleen cells of B6 mice did not support replication of HSV under any of the conditions we have tested thus far. The reasons for this defect are not clear, but it was obviously not caused by a defective lymphoproliferative response to LPS or by an active anti-viral principle elaborated by B6 spleen cells. F1 hybrids between B6 and D2 mice were capable of HSV replication to the same extent as were spleen cells of D2 mice. Several strains of both HSV-1 and HSV-2 could be replicated in D2 spleen cells cultures. Nylon column treatment of D2 spleen cells removed the ability to replicate HSV, whereas macrophage removal from the spleens by plastic adherence was without effect. Purified peritoneal exudate cells from D2 mice did not support replication of HSV. Together these data suggest that B cells activated by LPS represent the target cell of HSV replication in mouse spleen cell cultures.
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PMID:Replication of herpes simplex virus in mouse spleen cell cultures stimulated by lipopolysaccharide. 18 34

Spleen cells from C3H/HeJ mice are known to be unresponsive to mitogenic stimulation by LPS. We show here that T and B cell precursors of C3H/HeJ mice are unresponsive to induction of differentiation by LPS. Phenotypic differentiation of C3H/HeJ lymphocytes can be induced with DB-cAMP, Lipid A-associated protein, and with a serum factor induced by LPS in LPS responder strains.
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PMID:Induction of phenotypic lymphocyte differentiation in LPS unresponsive mice by an LPS-induced serum factor and by lipid A-associated protein. 19

Mice exposed to a sublethal dose of X-rays were immunized with alum-precipitated DNP-KLH (dinitrophenyl-keyhole limpet haemocyanin) and B. pertussis either before or after irradiation. The primary anti-DNP antibody response was evaluated during 8 weeks after immunization by the equilibrium dialysis technique using ammonium sulphate- precipitated serum globulins and the ligand 3H-labelled xi-DNP-L-Lysine. The serum concentrations of antibody sites in mice immunized 1-5 days before or 2 h-8 weeks after 450 rad were below the values in unirradiated controls at all bleeding times. Antibody affinity, however, was found to be up to 20 fold higher in irradiated mice than in control mice when antigen was injected before, or 3-8 weeks after, irradiation. Spleen cells from mice exposed to 450 rad 1-9 weeks before killing were stimulated in vitro with PHA, ConA, or LPS. Recovery profiles of mitotic responsiveness suggest that enhancement of antibody affinity in irradiated mice could result from relative lack of suppressor T Cells.
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PMID:Effects of whole-body irradiation on antibody affinity. 19 58

Spleen cells of B6 mice not previously immunized were induced to DNA synthesis by supernatants from HSV-infected tissue culture. The stimulatory principle could be passed through a 45-micrometer filter and sedimented at 100,000 x G. It was abolished by UV light, heating at 56 degrees C, and by an anti-HSV serum. The possibility that the observed stimulation was caused by LPS was therefore excluded, and there was a-so no indication of mycoplasma contamination. Partial purification of spleen cells from macrophages resulted in an increased stimulation by HSV. From experiments with nylon columns, anti-theta antibody, and nude mice it was concluded that HSV acted as a B cell mitogen. Strains of both HSV types 1 and 2 were stimulatory for B6 spleen cells. Of nine freshly isolated HSV strains with identical passage history (twice in HEF) four were strongly stimulatory, three showed a moderate stimulation, and two did not stimulate. Spleen cells from A/J and DBA/2 mice were stimulated to the same extent by HSV (WAL) as spleen cells from B6 mice. No viral replication was demonstrable in B6 spleen cell cultures stimulated for DNA synthesis by HSV. Thus our study demonstrates induction of cellular DNA synthesis in B lymphocytes by HSV which is abolished by inactivation of the virus.
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PMID:In vitro mitogenic stimulation of murine spleen cells by herpes simplex virus. 20 55


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