Search PubMed⌕ Search

Biomedical subjects

T Kaizu

Publications and source records attributed to T Kaizu.

At least 37 records · Page 2Linked to original sources

One-step sandwich enzyme-linked immunosorbent assay of human tissue plasminogen activator using monoclonal antibodies.

Five monoclonal antibodies to human tissue plasminogen activator (t-PA) were obtained. Three of them recognized a determinant designated alpha, and other two, another determinant named beta. A t-PA molecule was found to bear one each of determinants alpha and beta arranged in such a manner that the binding of alpha with one of its corresponding antibodies did not interfere with the binding of beta with one of its corresponding antibodies and vice versa. This allowed the development of a one-step sandwich enzyme-linked immunosorbent assay (ELISA) in which the antibody to beta was immobilized on wells of a microtiter plate and the bound t-PA was detected with the enzyme-conjugated antibody to alpha. The ELISA detected both one- and two-chain t-PA with a high sensitivity. We also discuss the determinants, alpha and beta.

Animals↗

Clinical application of monoclonal antibodies to small cell lung cancer.

Monoclonal antibodies to small cell lung cancer (SCLC) were produced by fusion of P3X63/AgU1 mouse myeloma cells with spleen cells from BALB/c mice immunized against intact cells of SCLC tumors grown in BALB/c athymic nude mice. The antibody TFS-2 demonstrated "pancarcinoma" reactivity showing binding to non-small cell lung cancer (NSCLC) and carcinomas derived from other organs such as stomach, pancreas, and colon. This antibody failed to react with a variety of normal tissues including lung, bone marrow, spleen, stomach, colon, and pancreas. TFS-2 showed complement-mediated cytolysis of target cells. TFS-2 had no significant effects on hematopoietic stem cells. This antibody will serve as a powerful tool for the in vitro removal of tumor cells from bone marrow, thus facilitating high-dose chemotherapy of SCLC with autologous bone marrow transplantation. In contrast, TFS-4 monoclonal antibody reacted specifically with SCLC but not with NSCLS tumors. This antibody can distinguish SCLC from NSCLC tumors in histologic diagnosis at transbronchial biopsy, and in cytological identification of tumor cells in malignant effusion, and in infiltrated bone marrow. Radiolabeled TSF-4 specifically accumulated into SCLC tumors that were implanted subcutaneously into athymic nude mice. Thus, the antibody will be useful not only for diagnosis of lung cancer but also for targeting anti-tumor agents.

Animals↗

Elimination of small cell lung cancer cells in vitro from human bone marrow by a monoclonal antibody.

We report here a useful method for elimination of small cell lung cancer cells in vitro from bone marrow. A monoclonal antibody, TFS-2, which mediates complement lysis and recognizes an antigen present on small cell lung cancer cells but not lymphoid cells or bone marrow cells, was used to clear infiltrated bone marrow. The antibody in the presence of complement effectively killed tumor cells, but it was not cytotoxic to bone marrow cells. When mixed populations consisting of tumor cells and bone marrow cells were treated with antibody and complement, the tumor cells were also effectively killed, except when large numbers of bone marrow cells were present, whereas TFS-2 had no significant effect on bone marrow stem cells, as judged by colony-forming unit assays.

Animals↗

Structures of the O-linked oligosaccharides of the major cell surface sialoglycoprotein of MAT-B1 and MAT-C1 ascites sublines of the 13762 rat mammary adenocarcinoma.

Structures of the principal O-glycosides from the major cell surface sialoglycoprotein (ASGP-1) of the MAT-B1 and MAT-C1 ascites sublines of the 13762 rat mammary adenocarcinoma have been determined. Oligosaccharitols were released by alkaline borohydride treatments of ASGP-1 and purified by gel filtration, DEAE-Sephadex ion exchange chromatography, and high performance liquid chromatography. On the basis of carbohydrate composition, methylation analysis, periodate oxidation, and exoglycosidase digestion, the five major oligosaccharides released by mild alkaline borohydride were assigned the following structures: Component II-3: (NeuAc alpha 2----3Gal beta 1----4GlcNAc beta 1----6)Ga 1 NAcOH(3----1 betaGa 1 3----2 alpha NeuAc) III-2a: (Ga 1 beta 1----4G1cNAc beta 1----6)Ga 1 NAcOH(3----1 beta Ga 1 3----2 alpha NeuAc) III-2c: (Ga 1 alpha 1----3Ga 1 beta 1----4G1cNAc beta 1----6) Ga 1 NAcOH(3----1 beta Ga 1 3----2 alpha NeuAc) IV-1a: (Ga 1 beta 1----4G 1 cNAc beta 1----6)Ga 1 NAcOH(3----1 beta Ga 1) IV-1c: (Ga 1 alpha 1----3Ga 1 beta 1----4G 1 cNAc beta 1----6) Ga 1 NAcOH(3----1 beta Ga 1) Fucosylated derivatives of III-2a, IV-1a, and IV-1c were found in smaller amounts with the fucose tentatively assigned to the 2-position of the lactosamine galactose. Components II-3, III-2a, and the fucosylated derivative of III-2A were found in both MAT-B1 and MAT-C1 sublines. The alpha-galactosides were found in detectable quantities only in subline MAT-B1. Oligosaccharides from MAT-C1 cells were enriched in sialic acid when compared to those from MAT-B1 cells. These results suggest that the 13762 ascites sublines, which bear different oligosaccharides, will provide models useful for the investigation of mechanisms regulating the expression of structures of the larger O-linked oligosaccharides.

Animals↗

Monoclonal antibodies to surface antigens of small cell carcinoma of the lung.

Monoclonal antibodies to membrane antigens of human small cell carcinoma of the lung were produced by fusion of P3X63/Ag8U1 mouse myeloma cells with spleen cells from BALB/c mice immunized against the intact cells of the small cell carcinomas grown in BALB/c nude mice. The hybrids were screened for antibody production using intact cells in a solid-phase radioimmunoassay or in a membrane fluorescence with a fluorescence-activated cell sorter. Four monoclonal antibodies were chosen that demonstrated reactivities with human small cell carcinoma of the lung and not with apparently normal diploid fibroblasts or lymphoblastoid cells. The antibodies designated as TFS-1 and TFS-2 rather demonstrated "pancarcinoma" reactivity, showing binding to the other types of lung cancer (adenocarcinoma, squamous cell carcinoma, and large cell carcinoma) and carcinomas derived from other organs, such as colon, pancreas, or stomach. The monoclonal antibodies TFS-3 and TFS-4 preferentially bound to small cell carcinoma cells and neuroblastoma cells, but not to non-small cell carcinomas (adenocarcinoma, squamous cell, or large cell). Especially, TFS-4 did not bind to a variety of other normal or malignant cells. Immunoprecipitation of the antigens by monoclonal antibodies and sodium dodecyl sulfate:polyacrylamide gel electrophoresis revealed that they had different molecular weights.

Animals↗

Synthesis of the branched form of erythroglycan by Friend GM979 erythroleukemic cells.

Mouse GM979 erythroleukemic cells were found to synthesize the branched form of erythroglycan, a large polylactosamine structure known to be attached to band 3 and possibly to other proteins on human erythrocytes. Total protein-derived oligosaccharides from GM979 cells, labeled metabolically with [3H]glucosamine, [3H]mannose, or [3H]galactose, were prepared by hydrazinolysis after extracting the lipids. The 3H-labeled oligosaccharides were fractionated on Sephadex G-50 revealing 10-25% of each labeled product as a high molecular weight fraction (Mr = 10,000). Digestion of this [3H]glucosamine fraction with endo-beta-galactosidase from Escherichia freundii, specific for the repeating structure of Gal beta (1 leads to 4)GlcNAc beta (1 leads to 3), resulted in the following four products upon Bio-Gel P-2 Gel filtration: 1) a disaccharide with the structure GlcNAc beta (1 leads to 3)Gal, 2) a trisaccharide with the structure Gal beta (1 leads to 4)GlcNAc beta (1 leads to 3) beta Gal, 3) a tetrasaccharide with the sequence Fuc alpha (1 leads to 2)Gal beta (1 leads to 4)GlcNAc beta (1 leads to 3)Gal, and 4) a large complex fragment which contained mannose, glucosamine, galactose, and fucose (presumably the protein linkage region). Methylation linkage analysis of the large complex fraction shows mainly the presence of 4-substituted and terminal N-acetylglucosamine; 3,6-substituted, 6-substituted, 2-substituted, and 2,3-substituted galactose. The GM979 cell erythroglycan is only 30% susceptible to endo-beta-galactosidase degradation probably because of the branched galactose residues, whereas the linear form of erythroglycan from human K562 cells is 60% susceptible. The branched residues in GM979 cell saccharides indicate that this mouse cell line bears an arborized erythroglycan-like glycopeptide similar to those found on human adult erythrocytes, and thus may be a source for the enzyme which transfers an N-acetylglucosamine residue to a 3-linked galactose to form a 3,6-disubstituted galactose.

Animals↗

A saturation transfer electron spin resonance study on the break in the Arrhenius plot for the rotational motion of Ca2+-dependent adenosine triphosphatase molecules in purified and lipid-replaced preparations of rabbit skeletal muscle sarcoplasmic reticulum.

By means of saturation transfer electron spin resonance spectroscopy the rotational motion of spin-labeled Ca2+-dependent ATPase molecules has been investigated for three kinds of preparations of rabbit skeletal muscle sarcoplasmic reticulum: MacLennan's enzyme (purified ATPase preparation), DOPC- and egg PC-ATPase (purified ATPase preparations in which endogenous lipids are replaced with dioleoyl and egg yolk phosphatidylcholine, respectively). The rotational mobility of the enzyme in these preparations is somewhat lower than that in the intact membrane, probably due to the reduced amount of lipids. For all the preparations, however, the Arrhenius plot for rotational mobility showed a break at about 18 degrees C, the same temperature at which a break in the Arrhenius plot for Ca2+-ATPase activity occurs. This result provides further evidence that the break in the Arrhenius plot is not related to a lipid phase transition but to a change in the physical state of the Ca2+-ATPase molecule existing in fluid lipids.

Animals↗

Mucus glycoprotein secretion by tracheal explants: effects of pollutants.

Tracheal slices incubated with radioactive precursors in tissue culture medium secrete labeled mucus glycoproteins into the culture medium. We have used an in vivtro approach, a combined method utilizing exposure to pneumotoxins in vivo coupled with quantitation of mucus secretion rates in vitro, to study the effects of inhaled pollutants on mucus biosynthesis by rat airways. In addition, we have purified the mucus glycoproteins secreted by rat tracheal explants in order to determine putative structural changes that might by the basis for the observed augmented secretion rates after exposure of rats to H2SO4 aerosols in combination with high ambient levels of ozone. After digestion with papain, mucus glycoproteins secreted by tracheal explants may be separated into five fractions by ion-exchange chromatography, with recovery in high yield, on columns of DEAE-cellulose. Each of these five fractions, one neutral and four acidic, migrates as a single unique spot upon cellulose acetate electrophoresis at pH values of 8.6 and 1.2. The neutral fraction, which is labeled with [3H] glucosamine, does not contain radioactivity when Na2 35SO4 is used as the precursor. Acidic fractions I-IV are all labeled with either 3H-glucosamine or Na2 35SO4 as precursor. Acidic fraction II contains sialic acid as the terminal sugar on its oligosaccharide side chains, based upon its chromatographic behavior on columns of wheat-germ agglutinin-Agarose. Treatment of this fraction with neuraminidase shifts its elution position in the gradient to a lower salt concentration, coincident with acidic fraction I. After removal of terminal sialic acid residues with either neuraminidase or low pH treatment, the resultant terminal sugar on the oligosaccharide side chains is fucose. These results are identical with those observed with mucus glycoproteins secreted by cultured human tracheal explants and purified by these same techniques.

Air Pollutants↗

Glycoprotein synthesis by an established cell line from hamster tracheal epithelium.

A cloned cell line, HTE-B, derived from hamster tracheal epithelium, synthesizes and secretes labeled glycoproteins in tissue culture. The glycopeptides derived from these glycoproteins by papain treatment are chromatographically and electrophoretically indistinguishable from those derived from glycoproteins secreted by cultured tracheal explants from rats or humans. The availability of this cell line should allow us to greatly increase our understanding of the mechanisms of glycoprotein synthesis and secretion by respiratory epithelial cells, and the underlying control mechanisms governing these processes.

Animals↗

Composition of glycoproteins secreted by tracheal explants from various animal species.

1. The acidic and neutral glycoproteins secreted by cultured tracheal explants from pigs, sheep, rats, mice, monkeys, guinea pigs, dogs and chickens were purified and fractionated by column chromatography on DEAE-cellulose and by electrophoresis on cellulose acetate. 2. The ratios of acidic to neutral mucus glycoproteins were compared for the above animals with that of mucus glycoproteins secreted by cultured human bronchi. 3. The observed ratios of acidic to neutral glycoproteins ranged from 4.0 (mouse) to 7.2 (chicken and pig) from cultured tracheae; secreted human bronchial mucus had a ratio of 2.7. 4. The ratio of acidic to neutral glycoproteins secreted by tracheal explants varied with duration of incubation of the trachea in culture.

Animals↗