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 ovarian-hormone-induced leukaemias of strain ICRC mice, with an abundance of intracytoplasmic type A particles in primary as well as transplanted lesions, were used to study morphological, biophysical, immunological and structural characteristics of type A particles. Mammary tumours of strains ICRC and C3H(Jax) were also used as sources for type A particles. The purified virions banded at the density of 1.20 g/ml in 12--60% linear sucrose-density gradient when subjected to spinning at 113,000 g for 4 h. The SDS-polyacrylamide-gel electrophoresis of type A particles from mammary tumours and leukaemias reproducibly resolved at least 8 polypeptides, 2 of these 54,000 and 24,000 dalton proteins, showing variable expression. Type A particles and B particles, despite the fact that each had a distinct polypeptide pattern, showed common antigens with different electrophoretic mobilities. Proteins of 24,000, 18,000 and 12,000 daltons from B particles were found to be antigenically related to those from type A particles. The bioassay studies carried out with purified A particles showed that 2/7 males of strain ICRC and 1/6 females of strain DBA-MTI developed leukaemias, as against none in the controls, when inoculated between the ages of 1-7 days. Spleen tumour and cervical tumour were seen in one female each of strain DBA-MTI.
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PMID:Intracytoplasmic type A particles from mammary tumours and leukaemias of strain ICRC mice. 10 57

The palmitoyl derivative of the linear polypeptide of poly-(L-Glu-L-Lys-L-Phe)n (GLphi) can be coupled to spleen cells directly. The intravenous administration of 2 X 10(5)--3 X 10(7) GLphi-coupled syngeneic spleen cells induces GL-phi-specific suppressor T cells in C57BL/6 nonresponder mice. The suppression is antigen specific and can be detected by the inhibition of the primary GLphi plaque-forming cell response to challenge with GLphi-fowl gamma globulin. The number of inducer cells required for suppression carry less than 0.1 microgram of antigen. Spleen cells from tolerized mice can transfer suppression to normal syngeneic recipients. The suppression is cyclophosphamide sensitive and the suppressor cells bear the Thy 1.2 marker. This method of inducing antigen-specific suppressor cells may be generally applicable to other antigen systems.
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PMID:Immune suppression in vivo with antigen-modified syngeneic cells. I. T-cell-mediated suppression to the terpolymer poly-(Glu, Lys, Phe)n. 30 20

Previous studies have demonstrated an inverse relationship between the net electrical charge of immunogens and the antibodies they elicit. This correlation was found to be expressed at the cellular level. It has been shown that thymus-derived cells may recognize immunogens on the basis of their overall electrical charge. In this study, charged T-independent copolymers composed of tyrosine, glutamic acid, and lysine of the D configuration were prepared in order to find out whether this net charge phenomenon holds also for immunogens which do not require helper T cells for generation of immune response. Spleen cells were fractionated over negatively charged glass bead columns, and their immunocompetence was tested by transferring them into irradiated recipient mice which were immunized with the dinitrophenylated acidic or basic T-independent carrier. No differences in the responsiveness to the dinitrophenyl group on either carrier could be detected in recipients of unfractionated or fractionated cells on the charged columns. Similar results were obtained with the negatively charged T-independent branched polypeptide poly-(DTyr,DGlu)-poly(DPro)--poly(DLys). Filtration of spleen cells through glass bead columns did not affect the immune response potential of the recipient mice. In contrast, a significant reduction was observed in the frequency of positive responses in recipients of filtered cells, which were immunized with the negatively charged T-dependent poly(DTyr,DGlu)-poly(DPro)--poly(DLys). Thus, the inverse net charge phenomenon holds only for T-dependent antigens.
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PMID:Lack of inverse relationship between the net charge of T-independent immunogens and the responding spleen cells. 108 Nov 4

Knowledge of the identity, synthesis and secretion of beta-galactoside-binding lectins by leukocytes is of importance because lactosaminoglycans present at the leukocyte cell surface may be physiologically significant lectin receptors that could mediate autocrine or paracrine functions and/or cell adhesion. This paper presents data that show that a previously identified 15.5-16.5 kDa lactose-binding protein synthesized in vitro by human peripheral leukocytes is actually comprised of three different polypeptides. One of these is related to a novel 15 kDa lectin isolated from human spleen and which is synthesized by B lymphoblastoid cells. Spleen contains at least six lactose-binding polypeptides for which the carbohydrate-binding activity is independent of the presence of divalent cations and mercaptoethanol. The splenic 15 kDa polypeptide does not appear to be immunologically related to previously characterized beta-galactoside-binding lectins. It is separable from galaptin, another galactoside-binding lectin (subunit mol. wt 14.5 kDa) by chromatography on DEAE-Sephacel. Western blot analyses and immunoprecipitation/fluorography experiments with metabolically labelled cells showed the presence of the 15 kDa lectin in peripheral leukocytes and in Epstein-Barr virus-immortalized B lymphoblastoid cells. The 15 kDa lectin yielded polypeptide fragments of approximately 6.2 and approximately 8.6 kDa after cyanogen bromide (CNBr) degradation. These fragments were partially sequenced and 12 residues/fragment were identified. A similarity search of the SWISS PROT protein data base did not reveal a relationship of the 15 kDa polypeptide to known lectins, including galaptin.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Identification and synthesis of a novel 15 kDa beta-galactoside-binding lectin in human leukocytes. 142 50

Spleen cells from BALB/c mice were fused with myeloma cells following infection of the mice with Trichinella spiralis larvae and an ip booster injection with larval homogenate antigen. A monoclonal antibody (Mab), designated as TS 3G6 which did not react with sera or tissue extracts from noninfected mice, rats, and guinea pigs, was selected for further studies because of its high activity and specificity. When tested in ELISA TS 3G6 did not cross-react with Ascaris suum, A. lumbricoides, Toxocara canis, E. granulosus (larvae), Trichiuris suis, or T. ovis. Western blot analysis showed that Mab 3G6 recognized an antigen of 76 kDa located in the stichosome of the larvae as well as on the surface of the larval cuticle. Digestion of a larval extract with different enzymes suggests that the Mab TS 3G6 corresponding epitope is a polypeptide. The TS 3G6 antigen was detected in culture supernatants of Trichinella muscle larvae and in sera of experimentally infected animals using a sensitive ELISA assay. This secretory antigen also seemed to induce a specific immune response in the host since sera from infected animals could block the binding of Mab TS 3G6 to its target antigen when tested in a competitive ELISA.
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PMID:Trichinella spiralis: a 76-kDa excretory/secretory larval antigen identified by a monoclonal antibody. 188 70

BALB/c mice were immunized with peroxisomal membranes prepared from rat liver. Spleen cells were fused with myeloma cells (P3/U1) and the hybridomas were selected using peroxisomal membranes. A monoclonal antibody (PXM1a/207B) which recognized peroxisomal membranes was selected. Using the antibody, a novel 57 kDa polypeptide was identified in the peroxisomal membrane fraction. Immunoblot analysis of the subcellular fractions demonstrated that the 57 kDa polypeptide was present exclusively in peroxisomal membranes. The 57 kDa polypeptide was partially digested by trypsin and chymotrypsin under conditions where peroxisomal particles remained intact, indicating that the polypeptide is exposed to the cytosolic face of the peroxisomal membrane. The amount of 57 kDa polypeptide increased in parallel with proliferation of peroxisomes by administration of clofibrate.
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PMID:A novel 57 kDa peroxisomal membrane polypeptide detected by monoclonal antibody (PXM1a/207B). 200 13

Hyperimmunization of BALB/c mice with concanavalin A-stimulated blasts from the Ig allotype-congenic strain, C.B20, results in the production of antibodies reactive with T cells in an allotype-restricted manner. Spleen cells from these hyperimmune BALB/c mice were used to generate a panel of hybridomas that secrete monoclonal antibodies, reactive, in an allotype-restricted manner, exclusively with T cells subpopulations, and in particular, reactive with suppressor T cell hybridomas and their secreted soluble factors. Two functional classes of antibodies were identified: those that react with single polypeptide-chain suppressor T cell factors (TsF1) and the suppressor T cell hybridomas that produce such factors, and those that react with two polypeptide-chain suppressor T cell factors (TsF2) and their corresponding suppressor T cell hybridomas. These two classes of antibody were used to isolate molecules from the membranes of the respective suppressor T cell hybrids that are functionally and structurally related to the secreted suppressor T cell factors, suggesting a receptor function for these molecules.
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PMID:Identification of Igh-C-linked determinants on suppressor T cell hybrids and factors specific for L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT). 241 40

Monoclonal antibodies to different domains of the porcine intestinal 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] receptor have been produced. A nuclear extract enriched in the 1,25-(OH)2D3 receptor was prepared from small intestinal mucosa of young pigs. The receptor was purified an additional 6600-fold by chromatography on DNA-cellulose, ammonium sulfate precipitation, gel filtration high-performance liquid chromatography, and DEAE-Sepharose chromatography, with an overall yield of 23% and an average purity of 24%. A BALB/c mouse immunized with this material developed serum polyclonal antibodies to the 1,25-(OH)2D3 receptor, as demonstrated by a change in sedimentation of the porcine receptor on sucrose gradients. Spleen cells from this animal were fused with mouse myeloma cells (P3-NSI/1-Ag4-1, SP2/0-Ag14), and 24 hybridomas secreting antibodies to the 1,25-(OH)2D3 receptor were identified by both a radiometric immunosorbent assay and an immunoprecipitation assay. Twenty-one hybridoma lines were cloned by limiting dilution and further characterized as subclass IgG1 antibodies with the exception of one which is an IgA. All but two of the antibodies cross-react with the 1,25-(OH)2D3 receptor from both mammalian (human, monkey, and rat) and avian (chicken) intestine; two antibodies recognize only porcine intestinal receptor. All antibodies are unreactive to the vitamin D serum transport protein. Eight of the antibodies bind denatured receptor on an immunoblot. A solid-phase competition assay was used to identify four groups of antibodies that bind to distinct epitopes on the 1,25-(OH)2D3 receptor. One antibody from each of the four groups was used to examine the effect of antibody binding on the DNA-binding activity of the receptor-hormone complex. One antibody completely inhibited the binding of the 1,25-(OH)2D3 receptor complex to DNA-cellulose, suggesting that the epitope for this antibody may be located in the polynucleotide binding domain of the protein. Antibodies from two additional groups only slightly perturbed DNA binding, while one had no effect, suggesting that these antibodies bind to receptor epitopes distant from the region of the polypeptide directly involved in polynucleotide binding. These antibodies that are directed to several different binding sites on the 1,25-(OH)2D3 receptor provide important new tools to probe the biochemistry and topology of the 1,25-(OH)2D3 receptor and to investigate its role in mediating target tissue response to hormone.
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PMID:Monoclonal antibodies to the porcine intestinal receptor for 1,25-dihydroxyvitamin D3: interaction with distinct receptor domains. 242 89

The retinal pigment epithelium consists of a unicellular layer of neuroepithelial cells that are essential for the maintenance of normal function of the neural retina. In order to evaluate more critically this cell in health and disease, we prepared monoclonal antibodies against human retinal pigment epithelial (RPE) cells. Balb/c mice were immunized with human RPE cells. Spleen cells were fused with myeloma cells and resultant hybridomas were selected for antibody production. Supernatants were assayed by immunoperoxidase on frozen sections of human eye tissues. Two hybrids were cloned and ascites were generated in mice. These IgG antibodies react only with RPE cells and show no cross-reactivity with other cells in the eye or with human brain, kidney, skin, salivary glands, lymphocytes or monocytes. These antibodies recognize cell surface molecules that are highly conserved since they can be found in man, monkey, rat, cow, chicken and frog. SDS gel electrophoresis and immunoblot analysis showed that one of the antibodies reacted with a 42,000 MW polypeptide. Evaluation of the developing rat retina revealed that the epitopes are not detected at birth, are weakly present at day 6 and are highly recognized by day 9. These immunoglobulins will allow us to evaluate RPE cells in disease (proliferation, migration) and to probe the bioregulatory functions (phagocytosis, vitamin A transport) of these cells.
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PMID:Development and characterization of monoclonal antibodies directed against the retinal pigment epithelial cell. 247 41

The first two steps of urea synthesis in liver of marine elasmobranchs involve formation of glutamine from ammonia and of carbamoyl phosphate from glutamine, catalysed by glutamine synthetase and carbamoyl-phosphate synthetase, respectively [Anderson & Casey (1984) J. Biol. Chem. 259, 456-462]; both of these enzymes are localized exclusively in the mitochondrial matrix. The objective of this study was to establish the enzymology of carbamoyl phosphate formation and utilization for pyrimidine nucleotide biosynthesis in Squalus acanthias (spiny dogfish), a representative elasmobranch. Aspartate carbamoyltransferase could not be detected in liver of dogfish. Spleen extracts, however, had glutamine-dependent carbamoyl-phosphate synthetase, aspartate carbamoyltransferase, dihydro-orotase, and glutamine synthetase activities, all localized in the cytosol; dihydro-orotate dehydrogenase, orotate phosphoribosyltransferase, and orotidine-5'-decarboxylase activities were also present. Except for glutamine synthetase, the levels of all activities were very low. The carbamoyl-phosphate synthetase activity is inhibited by UTP and is activated by 5-phosphoribosyl 1-pyrophosphate. The first three enzyme activities of the pyrimidine pathway were eluted in distinctly different positions during gel filtration chromatography under a number of different conditions; although complete proteolysis of inter-domain regions of a multifunctional complex during extraction cannot be excluded, the evidence suggests that in dogfish, in contrast to mammalian species, these three enzymes of the pyrimidine pathway exist as individual polypeptide chains. These results: (1) establish that dogfish express two different glutamine-dependent carbamoyl-phosphate synthetase activities, (2) confirm the report [Smith, Ritter & Campbell (1987) J. Biol. Chem. 262, 198-202] that dogfish express two different glutamine synthetases, and (3) provide indirect evidence that glutamine may not be available in liver for biosynthetic reactions other than urea formation.
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PMID:Glutamine-dependent carbamoyl-phosphate synthetase and other enzyme activities related to the pyrimidine pathway in spleen of Squalus acanthias (spiny dogfish). 257 May 70


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