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At least 127 records · Page 7Linked to original sources
PubMed1976

[On the biological characterization of the outbred strain of Chbb : NMRI (SPF) mice / 1st comm.: Characterization of breeding stock under constant conditions of nutrition (Part II) (author's transl)].

The second part continued the biological characteization of the outbred strain Chbb : NMRI (SPF) (formerly NMRI/Tübingen/Kisslegg/Biberach) mice. The results obtained from 7 generations (F9 to F 15-generations) refer to the following parameters: loss of breeding animals, conception rate, ability to build a nest, litter size at birth and weaning, loss of young animals, litter weight at birth and weaning, intervals between two births and efficienty quota.

Animals↗
PubMed1991

Purification and characterization of the 30,000 dalton native antigen of Mycobacterium tuberculosis and characterization of six monoclonal antibodies reactive with a major epitope of this antigen.

The 30,000 dalton native antigen of Mycobacterium tuberculosis is a major constituent of this organism and is secreted into culture medium. We purified this antigen by ammonium sulfate precipitation, ion-exchange chromatography, and reverse-phase high-performance liquid chromatography to yield a single 29 to 30 kd component. The first 20 N-terminal amino acid sequence was determined and found to be identical to that reported for M. bovis alpha-antigen. Immunoelectrophoresis studies demonstrated the purified 30,000 dalton antigen to be immunologically identical with antigen 6 and antigen 85B. The 30,000 dalton native antigen was a potent skin test antigen in sensitized guinea pigs. Six immunoglobulin G1 murine monoclonal antibodies against the 30,000 dalton antigen were generated. By enzyme-linked immunosorbent assay and western immunoblotting, all six monoclonal antibodies reacted with the 30,000 dalton antigen, perhaps with the same epitope. When used with culture filtrates of other mycobacteria, the monoclonal antibodies demonstrated reactivity with M. gordonae and M. kansasii and to a lesser extent with M. avium and M. scrofulaceum.

Amino Acid Sequence↗
PubMed1977

Isolation and characterization of immunoregulatory factors from normal human serum. I. Preliminary biochemical and biological characterization of immunosuppressive factors.

Normal human serum was shown to inhibit the mitogenic effects of bacterial lipopolysaccharide and Con A on mouse spleen lymphocytes and reduce the in vitro antibody response to SRBC by these cells. Furthermore, it was demonstrated that immune suppression occurred without loss of lymphocyte viability. Fractionation of normal human serum resulted in isolation of several immunoenhancing and immunoinhibitory fractions. Electrophoretic analysis of the immunoinhibitory fractions revealed a complex array of serum proteins. The most prominent proteins on polyacrylamide electrophoresis stained for both proteins and carbohydrate. The heterogeneity of immunoinhibitory fractions were further substantiated by their differential susceptibility to trypsin, periodate, and 2-mercaptoethanol treatment. Heterogeneity of the fractions was also shown to be related to difference in their biologic activity as expressed in their effects on mitogenicity and immunogenicity of LPS in mouse splenic cultures. This study lends evidence to the consideration that normal human serum contains several immunoregulatory factors with differing biochemical characteristics and cellular sites of action.

Animals↗
PubMed1988

Novel assay for pancreatic cellular damage: 1. Characterization of protein profiles in human pancreatic cytosol and purification and characterization of a pancreatic specific protein.

The protein patterns of cytosols from normal human pancreas and pancreatic carcinoma were studied by a two-dimensional separation technique using high-performance liquid chromatography followed by isoelectric focusing on polyacrylamide gels and visualization of the focused proteins by Coomassie Blue staining. Almost identical protein patterns were obtained for 20 different specimens from normal pancreas, whereas quite different protein patterns were found in 12 samples of pancreatic carcinoma. A major protein in normal pancreatic cytosol, not identical to any macromolecule previously tested as a marker for pancreatic function, was selected for further studies. The protein was not found in specimens of pancreatic carcinoma. It was purified by a single step chromatofocusing procedure, focused at pH 6.9, and moved as one single band in sodium dodecyl sulfate-polyacrylamide gel electrophoresis with an apparent molecular weight of 44,500 daltons. Total amino acid analysis revealed a high concentration of glutamic acid, leucine, and lysine. The purified protein had no amylase activity or lipase immunoactivity. It constituted approximately 2% of the total normal pancreatic cytosol protein. Later immunological studies have shown the protein to be highly specific for normal human pancreas, indicating a possible future use as a marker for pancreatic cell damage.

Adenocarcinoma↗
PubMed1989

Amastigote and epimastigote stage-specific components of Trypanosoma cruzi characterized by using monoclonal antibodies. Purification and molecular characterization of an 83-kilodalton amastigote protein.

Stage-specific mAb have been produced to amastigotes and epimastigotes of Trypanosoma cruzi (Brazil strain). mAb C-1 through C-6 reacted specifically with T. cruzi strains; no cross-reactions were found with membranes of promastigotes or amastigotes of Leishmania species. One mAb produced against the epimastigote membranes (C-5) was found to be specific against this stage by radioimmune binding assay, immunofluorescence, and radioimmunoprecipitation. mAb C-5 recognized a novel epimastigote protein at Mr (greater than 200,000) on immunoprecipitation with radiolabeled epimastigotes. Three amastigote stage-specific monoclonal antibodies were produced against membrane-enriched preparations of T. cruzi (Brazil strain) amastigotes grown in axenic culture (C-1 through C-3). By indirect immunofluorescence assay, monoclonal antibody C-2 bound only to T. cruzi amastigotes; no reaction with either tissue culture-derived trypomastigotes or epimastigotes was observed. mAb C-1 and C-2 each specifically immunoprecipitated a single protein molecule with Mr 83,000 from [35S]-methionine-labeled amastigotes. mAb C-2 was also used to affinity purify an 83-kDa Ag that was recognized by human Chagasic sera from patients of endemic countries of Latin America in an enzyme immunoassay. Amino acid composition and preliminary sequence data of the 83-kDa protein are presented. These mAb and/or purified Ag may be useful in studying stage differentiation, monitoring transformation, and for further taxonomic, epidemiologic, and immunologic studies of Chagas' disease.

Animals↗
PubMed1986

Purification and characterization of a novel inhibitor of urokinase from human urine. Quantitation and preliminary characterization in plasma.

Urokinase-related proteins in human urine occur mainly as a 1:1 complex of urokinase with an inhibitor (Stump, D. C., Thienpont, M., and Collen, D. (1986) J. Biol. Chem. 261, 1267-1273). BALB/c mice were immunized with this urokinase-urokinase inhibitor complex and spleen cells fused with mouse myeloma cells, resulting in hybridomas producing monoclonal antibodies. Three antibodies reacting with the complex but not with urokinase were utilized to develop a sensitive (0.5 ng/ml) enzyme-linked immunosorbent assay for the urokinase inhibitor, which was used for monitoring its purification by chromatography on zinc chelate-Sepharose, concanavalin A-Sepharose, SP-Sephadex C-50, and Sephadex G-100. A homogenous glycoprotein of apparent Mr 50,000 was obtained with a yield of 40 micrograms/liter urine and a purification factor of 320. One mg of the purified protein inhibited 35,000 IU of urokinase within 30 min at 37 degrees C. This protein was immunologically related to both the purified urokinase-urokinase inhibitor complex and to the inhibitor portion dissociated from it by nucleophilic dissociation. It was immunologically distinct from all known protease inhibitors, including the endothelial cell-derived fast-acting inhibitor of tissue-type plasminogen activator, the placental inhibitor of urokinase and protease nexin. In electrophoresis the protein migrated with beta-mobility. Inhibition of urokinase occurred with a second order rate constant (k) of 8 X 10(3) M-1 s-1 in the absence and of 9 X 10(4) M-1 s-1 in the presence of 50 IU of heparin/ml. The urokinase inhibitor was inactive towards single-chain urokinase-type plasminogen activator and plasmin, but it inhibited two-chain tissue-type plasminogen activator with a k below 10(3) M-1 s-1 and thrombin with a k of 4 X 10(4) M-1 s-1 in the absence and 2 X 10(5) M-1 s-1 in the presence of heparin. The concentration of this urokinase inhibitor in plasma from normal subjects determined by immunoassay was 2 +/- 0.7 micrograms/ml (mean +/- S.D., n = 25). The protein purified from plasma by immunoabsorption had the same Mr, amino acid composition, and immunoreactivity as the urinary protein. Furthermore, when urokinase was added to plasma, time-dependent urokinase-urokinase inhibitor complex formation was observed at a rate similar to that observed for the inhibition of urokinase by the purified inhibitor from urine. This urokinase inhibitor, purified from human urine, most probably represents a new plasma protease inhibitor.

Amino Acids↗
PubMed1987

Structural characterization of the Mr = 55,000 antigen (ZP3) of porcine oocyte zona pellucida. Purification and characterization of alpha- and beta-glycoproteins following digestion of lactosaminoglycan with endo-beta-galactosidase.

The major macromolecular component of the porcine oocyte zona pellucida is a Mr = 55,000 antigen, termed ZP3, comprised of greater than 25 charge isomers. ZP3 was purified to apparent electrophoretic homogeneity from nonreduced, sodium dodecyl sulfate-treated porcine zonae pellucidae by chromatography on Sephacryl S-400 and hydroxylapatite resins. The carbohydrate moiety of purified ZP3 was comprised of a heterogeneous population of acidic lactosaminoglycans as evidenced by the saccharide composition and size distribution of glycopeptides produced by Pronase digestion of ZP3, as well as by the sensitivity of ZP3 to digestion with Escherichia freundii endo-beta-galactosidase. Endo-beta-galactosidase-digested ZP3 was resolved by gel electrophoresis into two components, termed alpha-glycoprotein and beta-glycoprotein, with Mr values (nonreduced) of 46,000 and 42,000, respectively. Each was comprised of fewer and more neutral charge isomers than ZP3. Following purification by reverse phase high performance liquid chromatography, the alpha- and beta-glycoproteins of endo-beta-galactosidase-digested ZP3 were distinguished on the basis of amino acid and carbohydrate compositions, amino-terminal sequence analyses and peptide mapping experiments, thus suggesting differences in the primary structures of their respective polypeptide moieties. Corresponding dissimilarities in the immunoreactivities of the alpha- and beta-glycoproteins toward polyclonal antisera raised against ZP3, alpha-glycoprotein, and beta-glycoprotein were revealed by competitive binding radioimmunoassays as well as by immunoblotting experiments. Collectively, the data were interpreted to indicate that the Mr = 55,000 antigen of porcine oocyte zona pellucida is in fact comprised of overlapping families of charge isomers corresponding to two structurally and immunologically distinct lactosaminoglycan-containing glycoproteins.

Amino Sugars↗
PubMed1987

[Mutants of Saccharomyces cerevisiae characterized by increased level of induced mutagenesis. I. Isolation and preliminary characterization of mutants].

6 mutants with enhanced nitrous acid-induced reversibility of the ade2-42 allele were isolated and designated hm (high mutagenesis). Apart from sensitivity to the mutagenic exposure to nitrous acid, hm mutants were also spontaneous mutators and hypermutable under the action of UV-light and 6-N-hydroxyaminopurine. All these effects were detected not only when analysing reversibility of the ade2-42 allele, but also when scoring forward mutations in the ADE1, ADF2 genes. Gamma-mutagenesis, however, was not affected by hm mutations.

Alleles↗