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)

YAC, a Moloney-virus-induced tumor of A-strain mice, is a nonimmunogenic tumor. Mice injected with the inactivated neoplastic cells and challenged with viable tumor cells did not survive longer than mice that received the challenge dose alone. The homogenate of this nonimmunogenic tumor was subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). After electrophoresis, the gel slices containing isolated molecular entities were injected into various groups of mice. The mice were challenged with low doses of viable tumor cells (10-30 cells) and their survival time was recorded. Small but significant numbers of mice injected with apparent 80-90 K SDS-PAGE-isolated molecular entity rejected the tumor or survived longer than the control groups of mice. Spleen cells from mice injected with 80-90 K molecular entity inhibited the YAC tumor cotransferred with them to naive recipients (Winn assay). Spleen cells from mice injected with monoclonal antibody against nonspecific T-cell helper factor and immunized with 80-90 K SDS-PAGE-isolated molecular entity failed to inhibit the tumor growth in naive recipients, indicating that helper T cells are involved in induction of the antitumor resistance. Nylon-wool-passed splenocytes from mice injected with 80-90 K inhibited tumor growth in some of the recipient mice. Spleen cells from these mice treated with anti-Thy-1 and complement also inhibited the tumor growth in some of the recipients, suggesting that the effector cells were both T and non-T cells. C57BL/6 mice immunized with apparent 20 K SDS-PAGE-isolated molecular entity of RBL5 tumor also induced in vivo resistance to the syngeneic viable RBL5 cells, but not to the syngeneic B16 melanoma cells, indicating the specificity of the protective effect. The practical and theoretical implications of these findings are discussed.
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PMID:The isolation of immunogenic molecular entities from immunogenic and nonimmunogenic tumor homogenates by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). 623 88

A mitogenic substance, which stimulates murine and human B lymphocytes, has been isolated from the seeds of Ulex europeus. The m.w. of this mitogen was estimated to be approximately 100,000 by sodium dodecyl sulfate disc gel electrophoresis. Under physiologic conditions Ulex mitogen was in the form of a polymer. The isolated mitogen was found to contain 80% carbohydrate, in which glucose, galactose, and rhamnose were the predominant sugars. The carbohydrate portion of the mitogen could be responsible for the mitogenic activity, since the activity was destroyed by periodate treatment but not by protease digestion. It is unlikely that the mitogenic activity is due to the contamination by lipopolysaccharide (LPS), because Ulex mitogen strongly activated spleen cells from C3H/HeJ mice and did not contain a detectable amount of fatty acid. Spleen cells from nude mice, T-depleted spleen cells from conventional mice, or T-depleted spleen cells from conventional mice, or T-depleted lymphocytes from human peripheral blood responded as strongly as lymphocytes (T + B) from normal origin as measured by 3H-thymidine incorporation. It seems that the mitogenic effect is primarily on B cells. Ulex mitogen also induced the increase of immunoglobulin synthesis in murine and human B cells.
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PMID:Isolation and characterization of a mitogenic substance for murine and human B lymphocytes from Ulex europeus seeds. 626 9

Spleen cells from mice immunized with Epstein-Barr virus-transformed lymphoblastoid cells (EB-LCL) were used to generate monoclonal antibodies to cell surface antigens associated with the EB virus-transformed state. Radioimmune and immunofluorescence binding assays identified two antibodies, MHM6 and AC2, which reacted consistently with all EB-LCL tested, with a subpopulation of cells in some but not all EB virus genome-positive Burkitt lymphoma lines, but with none of a range of EB virus genome-negative cell lines of lymphoma or leukaemia origin. While MHM6 appeared to bind an EB virus-related antigen, AC2 bound some other cell surface antigen which was also found on a small subpopulation of cells in lymphocyte cultures stimulated with phytohaemagglutinin or with pokeweed mitogen. MHM6 and AC2 recognized single polypeptides with apparent molecular weights of 45 kd and 80 kd respectively as shown by sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of 125I-labeled cell surface polypeptides immunoprecipitated with these antibodies. These polypeptides were induced on experimentally-infected B cells within 24 h of the expression of the EB virus nuclear antigen, EBNA, at a time known to coincide with the appearance of the lymphocyte-detected membrane antigen, LYDMA. However, saturating concentration of MHM6 and AC2 were unable to protect EB-LCL target cells from lysis by LYDMA-specific cytotoxic T cells in a chromium-release assay.
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PMID:Monoclonal antibodies to Epstein-Barr virus-induced, transformation-associated cell surface antigens: binding patterns and effect upon virus-specific T-cell cytotoxicity. 628 62

Spleen cells from the South African clawed toad Xenopus laevis proliferate vigorously upon pokeweed mitogen (PWM) stimulation, as measured by 3H-thymidine uptake. The peak response is observed after 6-8 days of culture, and both light- and electron-microscopy examinations of stimulated cells reveal the presence of a large number of lymphoblasts. Beside proliferation, PWM induces the in vitro differentiation of a large proportion of lymphoblasts into immunoglobulin (Ig)-producing plasmablasts, as shown by direct immunofluorescence. On average, 25% of the lymphoblasts contain cytoplasmic high-molecular-weight Ig (IgM) at days 8-10, whereas less than 1% of the lymphoblasts have cytoplasmic low-molecular-weight Ig (IgY). Ig's of mitogen-stimulated cells were labeled biosynthetically and analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS/PAGE). The results confirm that Xenopus lymphoblasts induced in vitro synthesize Ig polypeptide chains. These are assembled into monomers of H2L2 units or polymerized hexameric forms. Both the monomer and hexamer forms are secreted. Two Ig heavy chains with apparent molecular weights (MW) of 74 and 81 daltons (kd) are detected in the cell lysates. The secreted chains have respectively an MW which is 3 kd and 5 kd greater than the intracellular forms. The two-dimensional gel electrophoretic pattern of PWM-induced Ig's is as heterogeneous as that of serum IgM. We conclude that PWM induces the in vitro proliferation and polyclonal differentiation of a large proportion of splenic B lymphocytes into plasmablasts.
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PMID:Mitogen-induced B-cell differentiation in Xenopus laevis. 633 1

The hybridoma technique, originally developed by G. Kohler & C. Milstein, is a powerful new experimental approach for analysis of complex biological systems, and is particularly suited for identification and study of surface-membrane antigens. This technique has been used for the production of monoclonal antibodies to intestinal brush border membrane proteins. Spleen cells, obtained from BALB/c mice immunized with purified brush border membranes, were fused with NSI mouse myeloma cells, and hybrids were selected with a culture medium containing hypoxanthine, aminopterin and thymidine (HAT medium). Hybridoma cultures were screened for production of specific antibodies by radio-immunobinding assays and by immunofluorescent staining of intestinal frozen sections. Selected hybridoma cultures were cloned twice and used for the production of large amounts of antibodies, which were characterized. Nineteen monoclonal antibodies have been prepared to date, about half of them specifically staining the brush border membrane of mature enterocytes. Ten of the antibodies specifically immunoprecipitate surface-membrane proteins, which were analysed by sodium dodecyl sulphate slab-gel electrophoresis, by two-dimensional slab-gel electrophoresis, and by specific enzyme assays. Two antibodies were found to be specific for sucrase-isomaltase, one for an aminopeptidase, two for an isoenzyme of alkaline phosphatase that is present exclusively in the proximal small intestine, and one for maltase-glucoamylase. These monoclonal antibodies, and others prepared by similar techniques from mice immunized with a wide variety of intestinal subcellular fractions, should prove invaluable tools for the study of the biosynthesis of cell-surface proteins, the fetal and postnatal development of specific intestinal functions, and the process of cell differentiation in the intestinal epithelium.
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PMID:Use of monoclonal antibodies in the study of intestinal structure and function. 634 93

Spleen cells from mice immunized with partially purified hog kidney renin were fused with mouse myeloma cells to produce a stable monoclonal hybridoma cell line that synthesizes an antibody against renin. A single monoclonal antibody was chosen for study and has been produced in large quantity and purified by affinity chromatography on protein A-Sepharose. The antirenin, which belongs to the IgG1 subclass, exhibits anticatalytic activity against both hog and rabbit renin. An immunoaffinity column prepared from antibody coupled to Sepharose has been used in the purification of renin from hog kidney. Although renin is quantitatively adsorbed from solution, it can be eluted from the column under gentle conditions. The highly purified renin, with specific activity of 2122 Goldblatt Units/mg protein, exhibits both charge (pH 4.1 to 5.1) and size (38,000 to 42,700) heterogeneity. Hog kidney renin dissociates in the presence of sodium dodecyl sulfate (SDS) and mercaptoethanol to heavy and light chains with molecular weights of 33,700 and 5,800, respectively. In the presence of SDS, a small amount of a nw form of renin is observed with a molecular weight of 19,500 which retains activity on renaturation. The monoclonal antibody should be a useful tool for the study of the renin-angiotensin system and especially for the purification of renin. The hybridoma cell line used in this study (F-32 VIII C4) has been donated to the American Type Culture Collection.
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PMID:Purification of hog kidney renin with immobilized monoclonal antirenin. 637 44

This study examined the metabolism of arachidonic acid (20:4) by splenic mononuclear cells from BALB/c mice infected with Leishmania donovani. Spleen cells removed from mice after either 4 or 8 weeks of infection and cultured in the presence of phytohemagglutinin (PHA) incorporated 60-70% less [3H]thymidine and synthesized 2- to 5-fold more prostaglandin E2 than did spleen cells from normal mice. Inhibition of cyclooxygenation by sodium meclofenamate was associated with restoration of PHA-induced spleen cell blastogenesis. Thin-layer chromatography of spleen cell extracts showed that PHA-stimulated spleen cells from infected animals synthesized 54 and 27% more 5-hydroxyeicosatetraenoic acid (5-HETE) and 12/15-HETE respectively, when compared to spleen cells from noninfected mice. Culture medium of spleen cells from infected mice also contained 25% more immunoreactive leukotriene C4. Nordihydroguaiaretic acid (3 microM) reduced spleen cell synthesis of 12/15-HETE while minimally affecting 5-HETE production. These data indicated that increased cyclooxygenase and lipoxygenase activities in spleen cells from mice infected with L. donovani resulted in the generation of 20:4 metabolites with the capability of altering T-lymphocyte function.
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PMID:Arachidonic acid metabolism in murine leishmaniasis (Donovani): ex-vivo evidence for increased cyclooxygenase and 5-lipoxygenase activity in spleen cells. 643 88

Rat thymocytes were exposed in vitro to the corticosteroid dexamethasone, 10 nM, for 10 min, or to oleic acid, 500 nM for 2 min. This results in cytolysis after 6 hr, if incubation is continued. Instead, the cells were centrifuged, the supernatant fluid decanted, and the cells subjected to osmotic shock in 1.5 mM MgCl2. The naked nuclei were incubated at 37 degrees C and examined by light and electron microscopy. Nuclear edema was evident early, and most nuclei showed damage with variation in shape and size and distinct folds, which was maximal by 1-2 hr as a result of these treatments. This was true also if nuclei were incubated in MgF2 or Mg(NO3)2 but not in MgBr2, MgI2, MgSO4 or Mg-citrate. Spleen lymphocyte nuclei showed similar damage but only after incubation with 20 microM oleic acid, and not at all with corticosteroids. The effects of both steroid and fatty acid, even at greatly increased concentrations, were inhibited by tri-n-butyl tin chloride, 10 microM, and by 4-4'-diisothiocyanostilbene-2,2'-disulfonic acid, sodium salt, 10 microM, both of which block chloride ion transport. It is concluded that the cytolytic effects of both corticosteroids and free fatty acids involve influx of chloride ion resulting in nuclear edema, which subsequently leads to fragmentation of chromatin, karyorrhexis and, ultimately, cytolysis.
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PMID:Role of anions in the lymphocytolytic action of corticosteroids and fatty acids. 649 16

Peroxidase was purified from uteri of estrogen-treated rats by calcium chloride extraction, affinity chromatography on concanavalin A-Sepharose and hydrophobic interaction chromatography on phenyl-Sepharose. An overall purification of greater than 1700-fold was achieved with a final recovery of 27%. Monoclonal antibodies to peroxidase were subsequently prepared by immunization of male C57BL/10J mice with the highly purified peroxidase from rat uterus. Spleen and lymph node cells from the mice were fused with Sp2/0-Ag 14 mouse myeloma cells. The resultant hybrid cells were screened for production of antibody using a solid-phase, double antibody radioimmunoassay. The mature rat spleen, shown previously to be abundant in eosinophils, contains high peroxidase activity. Spleen peroxidase purified by the same procedure as the uterine enzyme cross-reacted with a monoclonal antibody, designated IgG-107B, used in all subsequent studies. Peroxidase extracted from isolated rat eosinophils also cross-reacted with the antibody and yielded identical titers as the spleen and uterine peroxidases. Spleen, uterine and horse eosinophil peroxidase had the same apparent molecular weight, 57000, as determined by sodium dodecyl sulfate-urea polyacrylamide gel electrophoresis. Following electrophoretic transfer to nitrocellulose, spleen, uterine and eosinophil peroxidase reacted with monoclonal antibody, using an immunoblotting technique. These results provide biochemical and immunological evidence that the majority of the calcium chloride-extractable peroxidase activity from the uteri of estrogen-treated rats is derived from infiltrating eosinophils.
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PMID:Monoclonal antibody to rat uterine peroxidase and its use in identification of the peroxidase as being of eosinophil origin. 650 85

Rat spleen kallikrein was identified and purified by DEAE-cellulose and monoclonal antibody-affinity chromatography. The purified enzyme has Tos-Arg-OMe esterase activity and kinin-releasing activity from a purified low-molecular-weight kininogen substrate. In the direct radioimmunoassay for tissue kallikrein, the splenic enzyme displays parallelism with standard curves of rat urinary kallikrein. The pH profiles of the Tos-Arg-OMe esterase activities of spleen and urinary kallikrein were identical with optima at 9.0. Rat spleen kallikrein was inhibited strongly by aprotinin and affinity-purified kallikrein antibody and weakly by soybean trypsin inhibitor. The IC50 values were similar to those observed against rat urinary kallikrein. Neither the urinary nor the splenic enzyme was inhibited by lima bean trypsin inhibitor or preimmune serum immunoglobulins. Spleen kallikrein was labeled with [14C]diisopropylphosphorofluoridate and visualized by fluorography on a sodium dodecyl sulfate-polyacrylamide gel. The electrophoretic mobility of the splenic enzyme was indistinguishable from that of urinary kallikrein A with an estimated Mr of approx. 38 000. With Western blot analyses using a rabbit anti-kallikrein antibody followed by 125I-labeled protein A binding, the spleen and urinary kallikreins were again visualized at identical positions by autoradiography. The data show that there is a rat splenic tissue kallikrein which is indistinguishable from a renal kallikrein with respect to physicochemical properties, immunological character and susceptibility to inhibitors.
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PMID:Isolation of tissue kallikrein in rat spleen by monoclonal antibody-affinity chromatography. 656 77


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