Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.10.1 (ERK)
 95,504 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Our studies clearly show that significantly longer remission duration was attained in groups of AML patients immunized with neuraminidase treated allogeneic myeloblasts as compared to patients who received chemotherapy alone or neuraminidase treated myeloblasts plus MER. IT is clear that MER, albeit apparently active alone in certain other clinical studies impairs the immunotherapeutic value of neuraminidase treated allogeneic myeloblasts in AML patients. The in vivo and in vitro immunological tests results reflect the host's immunological status in each arm of the protocol and correlate well with the duration of remission achieved with specific vs. combination of specific plus adjuvant immunotherapy.
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PMID:Impact of specific immunotherapy in acute myelocytic leukemia. 16 58

One hundred forty-four Wistar-Furth rats in 12 therapeutic groups have been studied in a long-term comparison of the effectiveness of nonspecific immunotherapy with MER (methanol extraction residue) vs active-specific immunotherapy with neuraminidase-modified tumor cells. Six months after surgical adjuvant immunotherapy a 100% improvement in survival was achieved with MER immunotherapy compared to untreated control animals. In addition, the use of MER enhanced the value of active-specific immunotherapy where both modalities were combined in sequence. The predicted value of MER-BCG (Bacillus Calmette-Guerin) for the immunotherapy of solid tumors was borne out by these results suggesting that present ongoing clinical trials of MER as adjuvant therapy for large bowel cancer should prove to be successful if properly controlled. The pattern of survival in these experiments suggests that surgical adjuvant immunotherapy is cytostatic rather than cytocidal, and implies the need for long-term, repeated immunizations.
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PMID:Surgical adjuvant immunotherapy for colorectal cancer. 73 27

The immunogenicity of leukemia L1210 in DBA/2 Ha and 6C3HED lymphosarcoma tumor cells in C3H/f mice was significantly increased after treatment with V. cholerae neuraminidase. DBA/2 Ha and C3H/f mice repeatedly immunized with neuraminidase-treated tumor cells rejected subsequent challenge of 10(7) or 10(6) untreated tumor cells, respectively. Based on the 51Cr microcytotoxicity assay, both strains of mice showed strong complement-dependent antibody titers and cell-mediated immunity. Sera and splenic lymphocytes from immunized C3H/f mice neutralized the tumorigenicity of 6C3HED lymphosarcoma and protected the recipient C3H/f mice against the disease. Immune lymphocytes pretreated with anti-theta sera lost their ability to neutralize the tumorigenicity of lymphosarcoma, and they failed to be stimulated by T-cell mitogens. We studied the effectiveness of chemoimmunotherapy in DBA/2 Ha mice with leukemia L1210. A single near optimal dose of BCNU 2 days after implantation of 10(6) tumor cells increased the survival time. A single immunization with 2 X 10(7) neuraminidase-treated L1210 tumor cells 4 days after cytoreductive therapy increased survival and resulted in cures for 50% of animals. Immunization of mice with neuraminidase-treated tumor cells and MER produced indefinite survival in a larger percentage of mice than did either treatment alone. AKR mice with spontaneous leukemia treated with combination chemotherapy sustained an 180% increase in life-span. Combination chemotherapy plus immunization with neuraminidase-treated syngeneic or allogeneic (Gross virus-induced) E2G leukemia cells were highly effective in prolonging the life-span of the immunized leukemic AKR mice. The experimental data led to clinical trials in acute myelocytic leukemia with neuraminidase-treated a-logeneic myeloblasts. Patients with acute myelocytic leukemia were randomized into two groups after remission induction. The median remission duration of patients on sustaining chemotherapy alone was 19 weeks (8 patients), whereas six of nine patients who received neuraminidase-treated allogeneic myeloblasts remain in remission 79-132 weeks. Statistical analysis of the remission duration and survival of patients who received chemoimmunotherapy versus the control group shows highly significant differences.
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PMID:Therapeutic effectiveness of neuraminidase-treated tumor cells as an immunogen in man and experimental animals with leukemia. 106 51

An immobilized enzyme system has been developed and employed to determine the concentration of sialic acid (N-acetylneuraminic acid) in human serum and urine. Two enzyme pairs, neuramindiase-Neu-5-Ac lyase and pyruvate oxidase-peroxidase, have been respectively co-immobilized onto 1,12-aminododecane-agarose with glutaraldehyde. The relative specific activity of the co-immobilized neuraminidase and Neu-5-Ac lyase were 60% and 78%, and those of pyruvate oxidase and peroxidase were 50% and 95% of the corresponding soluble enzymes, respectively. The optimal reaction pH at 37 degrees C for each of the co-immobilized enzymes was about one pH unit higher than that of the corresponding soluble enzyme. The optimal reaction temperature of each enzyme was increased as a result of immobilization. The thermal stability at 45 degrees C of the immobilized neuraminidase, Neu-5-Ac lyase, pyruvate oxidase, and peroxidase were increased 80-, 83-, 115-, and 147-fold, respectively. Km and Vm of each immobilized and co-immobilized enzyme have also been determined. The system provided a convenient and rapid method to determine the concentration of total sialic acid without pretreatment of the sample. The results correlated satisfactorily with those obtained by using a soluble enzyme system. The co-immobilized enzymes were stable for at least 1 year of 500 tests when used repeatedly. The system is thus a reproducible and reliable novel assay method for sialic acid in the serum or urine sample.
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PMID:Immobilized enzyme system for determination of sialic acid in serum or urine. 136 58

We investigated the glycoconjugates of the human bronchial glands at light and electron microscopic level by means of lectin histochemistry in combination with neuraminidase digestion and beta-elimination reaction. Both direct and indirect techniques using lectin-peroxidase, lectin-gold, and glycoprotein-gold complexes were applied. The binding pattern of the six lectins (ConA, HPA, DSA, WGA, LEA, and PNA) used in the present study suggests that mucous and serous cells of human bronchial glands contain both N- and O-glycosylated proteins in the secretory granules. Asparagine-linked oligosaccharides containing Gal(beta-1,4) GlcNAc and Man residues were abundant in serous cells. The demonstration of both the terminal Neu 5Ac (alpha-2,3, or 6) Gal (beta-1,4) GlcNAc sequence in the N-linked oligosaccharides of mucous cells and the terminal disaccharide Gal (beta-1,4) GlcNAc in the N-linked oligosaccharide chains of serous cells suggests the existence of complex type sugar chains N-glycosidically linked to the peptide region of the glycoproteins. The binding pattern of the DSA and the neuraminidase-DSA sequence provides evidence for the existence of sialyltransferase activity in the forming mucous granules of mucous bronchial cells.
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PMID:Ultrastructural localization of glycoconjugates in human bronchial glands: the subcellular organization of N- and O-linked oligosaccharide chains. 155 69

Flow cytometric analysis employing monoclonal antibodies to the Tn antigen and glycophorin A was used to characterize the erythrocyte populations present in blood samples from individuals with Tn syndrome. Four monoclonal antibodies specific for the Tn antigen, Gal-NAc monosaccharide, on human erythrocytes were obtained from a fusion of splenocytes from a Biozzi mouse immunized with red cells from a Tn individual. These monoclonal antibodies specifically recognize GalNAc monosaccharide sites located on the erythrocyte cell surface sialoglycoproteins, glycophorin A and glycophorin B, and do not bind to fixed normal red cells presenting the Neu-NAc alpha 2-3Gal beta 1-3(NeuNAc alpha 2-6)GalNAc alpha 1-O-Ser(Thr) tetrasaccharide or to fixed neuraminidase-digested cells presenting the Gal-GalNAc disaccharide. The percentages of Tn-positive red cells in samples from six unrelated Tn donors ranged from 28 to 99%. Binding of the glycophorin A-specific monoclonal antibodies showed that the erythrocytes composing the Tn-negative fraction presented normal amounts of the M and N epitopes on glycophorin A. The presumed somatic mutational origin of Tn-positive cells was tested in blood samples from five normal donors; three possible Tn cells were observed after analysis of a total of 1.1 x 10(7) erythrocytes, suggesting that the frequency of such cells in normal individuals is less than 1 x 10(-6).
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PMID:Flow cytometric analysis of erythrocyte populations in Tn syndrome blood using monoclonal antibodies to glycophorin A and the Tn antigen. 169 Jun 28

Cell surface molecules play an important role in cellular communication, migration, and adherence. Here, we show the effect of organ-derived biomatrices on endothelial cell surface glycosylation. Five different lectins (with and without neuraminidase treatment) have been used as probes in an enzyme-linked lectin assay to quantitatively detect glycoconjugates on endothelial cells (BAEC) grown on tissue culture plastic or biomatrices isolated from bovine lung, liver, and kidney. BAEC generally exhibit strong binding of concanavalin A (Con A), Ricinus communis agglutinin I (RCA-I), wheat germ agglutinin (WGA), and soybean agglutinin, and peanut agglutinin after neuraminidase pretreatment of cells (Neu-SBA and Neu-PNA), while SBA and PNA consistently bind weakly to BAEC. BAEC grown on organ-derived biomatrices exhibit significantly altered binding intensities of Con A, RCA-I, WGA, and Neu-PNA: BAEC cultured on lung- or kidney-derived biomatrices express significantly stronger binding affinities for Con A and RCA-I than BAEC grown on liver-derived biomatrix or tissue culture plastic. In contrast, BAEC binding of WGA and PNA (after treatment of cells with neuraminidase) is significantly reduced when BAEC are grown on liver- or kidney-derived biomatrix. Quantitative lectin immunogold electron microscopy reveals consistently stronger lectin binding over nuclear regions compared to junctional regions between neighboring cells. These results indicate that extracellular matrix components regulate endothelial cell surface glycoconjugate expression, which determines cellular functions, e.g., preferential adhesion of lymphocytes or metastatic tumor cells.
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PMID:Modulation of endothelial cell surface glycoconjugate expression by organ-derived biomatrices. 198 84

Cell surface glycoconjugate expression of endothelial cells in canine cutaneous hemangiomas and hemangiosarcomas was compared to normal cutaneous endothelial cells using eight different lectins (with and without neuraminidase pretreatment) in an indirect immunoperoxidase technique. Direct comparison of lectin binding pattern of neoplastic endothelial cells with adjacent normal endothelial cells revealed minor changes in the binding intensity of several lectins (enhanced: Wheat germ agglutinin [WGA]; reduced: Griffonia simplicifolia-I [GS-I], Ricinus communis agglutinin-I [RCA-I], Soybean agglutinin after neuraminidase pretreatment [Neu-SBA], and Wheat germ agglutinin after neuraminidase treatment [Neu-WGA]). Neoplastic endothelial cells in some tumors exhibited varying binding of Ulex europaeus agglutinin-I (UEA-I; not binding to normal canine endothelial cells) and no Soybean agglutinin (SBA) binding (variably binding to normal endothelial cells in small cutaneous vessels). Lectin binding of neoplastic cells was rather heterogenous within one tumor compared to the uniform binding pattern of normal endothelial cells. These lectin binding studies demonstrate the phenotypic heterogeneity of neoplastic endothelial cells, indicating changes of cell surface glycosylation during neoplastic transformation.
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PMID:Phenotypic characterization of normal and neoplastic canine endothelial cells by lectin histochemistry. 218 54

A striking discrepancy in the abilities of two analytical approaches (fluorometric and electrophoretic) to detect the effect of a gene, Neu-2, on rat liver neuraminidase phenotypes led us to examine the biochemical and physical properties of the liver isozymes NEU-1 and NEU-2 that might be responsible for this difference. Cell fractionation via Percoll gradient centrifugation revealed NEU-1 activity almost exclusively in the lysosomal cell fraction, while NEU-2 was strictly cytosolic in distribution. The two isozymes were also found to differ in pH activity curves and optima (optima: 4.6-4.8 and 5.4-5.8 for NEU-1 and NEU-2, respectively) and in solubility characteristics (NEU-2 highly soluble; NEU-1 relatively insoluble but solubilized by freezing/thawing). Both isozymes were found to be freeze-thaw stable in crude, whole-cell extracts, but NEU-1 was destabilized in the enriched (partially purified) lysosomal subcellular fraction. Consideration of these properties relative to those described previously for unidentified cytosolic and membrane bound (lysosomal) rat liver neuraminidases (Tulsiani, D. R. P., and Carubelli, R., J. Biol. Chem. 245:1821, 1970) leads us to believe that NEU-2 also is destabilized by partial purification and that NEU-1 and NEU-2 have very different relative abundances within the cell. The biochemical and physical differences between NEU-1 and NEU-2 can account for the discrepant abilities of the fluorometric and electrophoretic approaches to detect the effects of Neu-2. Ways to increase the sensitivity of the fluorometric approach for quantitative assays of specific NEU-1 and NEU-2 activity are discussed.
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PMID:Biochemical characteristics and subcellular localizations of rat liver neuraminidase isozymes: a paradox resolved. 239 82

This work is part of an investigation into G. I. mucin susceptibility to enzyme degradation in normal and disease states. Formalin-fixed/paraffin embedded foetal (14-23 weeks) and neonatal colonic tissue was stained for mucins (neutral, N- and O-acylated sialomucins and sulphomucins) and PNA, UEA1, and Limax flavus. Enzymes tested: neuraminidases, alpha- and beta-galactosidase (E. coli and B. testis), beta-N-acetyl-glucosaminidase, alpha-fucosidase, single or in sequence, with and without prior neuraminidase treatment and followed by the stains. Acid mucins predominate throughout foetal life, sulphation occurs at 14 weeks and O-acylated sialomucins at 23 weeks. PNA and UEA1 are seen in traces or not detected. The mucin profile at birth is similar to the adult. Colonic mucins are susceptible to neuraminidase which abolishes Limax staining. The glycosidases effect on PNA is seen only with prior neuraminidase treatment and is particularly marked with beta-Gal(BT) in Neu----beta-Gal----beta-N-AcetylGlc than with beta-Gal (EC). Fucosidase with prior neuraminidase treatment has effect on UEA1 (decreases) and PNA (increases) affinities. Neuraminidase is essential as a first step in the process and by using beta-galactosidases EC and BT it was possible to show different PNA binding affinities. Preliminary data demonstrate the feasibility of this histochemical approach to the study of colonic mucins and forms the basis for further studies in the adult.
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PMID:Goblet cell mucin in human foetal colon, its composition and susceptibility to enzyme degradation: a histochemical study. 264 9


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