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Biomedical subjects

Y Terano

Publications and source records attributed to Y Terano.

At least 37 records · Page 2Linked to original sources

Drug-specific T cells derived from patients with drug-induced allergic hepatitis.

Drug-induced allergic hepatitis is a tissue-specific inflammatory disease caused by hypersensitivity to a particular drug. Although the frequency of drug-induced allergic hepatitis appears to increase in proportion to the medicine, the mechanism by which tissue specificity is determined is still to be elucidated. In this study, we established CD4+ T cell clones specific for particular drugs from patients with drug-induced allergic hepatitis accompanied with mild blood eosinophilia and analyzed the possible role of liver protein as a directing factor of liver-specific inflammatory reactions. All CD4+ T cell clones obtained from two patients with this disease proliferated in response to a combination of the particular drug plus liver specific protein (LSP), which consists of over 30 proteins. Some T cell clones were responsive to an antigenic conformation consisting of the 200-kDa glycoprotein (partly purified LSP), a component of LSP, plus the causal drug. In contrast, all CD4+ T cell clones from a patient with simple drug-induced eosinophilia responded to the causal drug in the absence of LSP and partly purified LSP. These data suggested that LSP or partly purified LSP of the appropriate Ag is the target that leads to liver-specific inflammation in drug-induced allergic hepatitis. Furthermore, T cell lines derived from patients with drug-induced allergic hepatitis and simple drug-induced eosinophilia produced large amounts of IL-5 after the appropriate antigenic stimulation, whereas CD4+ T cell clones from donors with a normal amount of peripheral blood eosinophils secreted a much less IL-5. Taken together, these results indicate that overproduction of IL-5 by the allergen-sensitized T cells may result in blood eosinophilia.

Adult↗

Induction of metallothionein synthesis by menadione or carbon tetrachloride is independent of free radical production.

The relationship between induction of hepatic metallothionein (MT) synthesis and lipid peroxidation by free radical production following an injection of menadione or carbon tetrachloride (CCl4) in mice was studied. The hepatic concentration of MT was increased by menadione significantly at 25 mg/kg or higher. A significant increase in thiobarbituric acid (TBA) value, indicative of lipid peroxidation, was observed in the liver at menadione doses of 62.5 mg/kg or higher. Both the MT and the TBA value in the liver were significantly increased at the low dose of CCl4. The concentration of MT was increased significantly 4-8 hr after administrations of these compounds. The increase of TBA value over time was similar to that of MT concentration after administration of CCl4, but not after administration of menadione. The MT concentration in the menadione group was higher than that in the CCl4 group, and the TBA level in the menadione group was lower than that in the CCl4 group. Pretreatment with vitamin E caused a significant reduction in the TBA value, but did not affect the MT level in the liver. The concentration of MT did not significantly correlate with the TBA value in either the menadione or the CCl4 group. Pretreatment with phenobarbital, which promotes free radical production, did not influence induction of MT synthesis following an injection of menadione or CCl4. Neither L-buthionine sulfoximine nor 2-cyclo-hexen-1-one, which decreases hepatic glutathione, influenced the induction of MT by menadione. These data suggest that induction of MT synthesis by menadione or CCl4 is independent of free radical production in the liver.

Animals↗

Monoclonal antibody to human plasma gelsolin.

Human plasma gelsolin was purified by column chromatography. The method yielded a protein of high purity and activity. Using this protein, we produced monoclonal antibody (Mab H6B11) against human plasma gelsolin by somatic cell fusion. This monoclonal antibody reacted in a dose-dependent manner with gelsolin derived from human plasma and platelets and neutralized depolymerizing activity to F-actin. It differed from the commercially available substance (Mab G4896; Sigma) in that the time required for the reaction between the antigen and antibody in the enzyme-linked immunosorbent assay could be shortened by one-third. The antibody was judged to be useful in assays for elucidating the physiological role of plasma gelsolin.

Animals↗

Induction of hepatic metallothionein by nonmetallic compounds associated with acute-phase response in inflammation.

Induction of hepatic metallothionein (MT) synthesis by several nonmetallic compounds and its relationship to an acute-phase response in inflammation were studied in mice. Subcutaneous injections of menadione, paraquat, carbon tetrachloride (CCl4), and several organic solvents caused an increase of hepatic MT concentration. This MT contained only zinc. Menadione and n-hexane caused the greatest accumulation of hepatic MT among these nonmetallic compounds (about 13-fold). The concentration of Zn was significantly decreased in plasma in contrast to liver after an injection of these nonmetallic compounds. When 65ZnCl2 was injected iv after these injections, uptake of 65Zn to the liver was increased. This effect was not observed after treatment with cycloheximide. The association with inflammation of this induction of MT accumulation was examined by determination of acute-phase proteins. The concentration of fibrinogen in the plasma was significantly increased following injection of those nonmetallic compounds which caused marked hepatic MT accumulation. An injection of 1 N NaOH, 1 N HCl, turpentine oil, or endotoxin caused a significant increase in the plasma concentration of fibrinogen and in the hepatic MT concentration. Injections of n-hexane as well as turpentine oil significantly increased hepatic MT concentration and plasma concentration of fibrinogen and ceruloplasmin with time. The concentration of fibrinogen was significantly correlated (r = 0.789) with the concentration of hepatic MT. Neither adrenalectomy nor pretreatment with dexamethasone prevented hepatic MT accumulation caused by these compounds. These results indicate that induction of hepatic MT synthesis by these nonmetallic compounds is associated with an acute-phase response in inflammation and is independent of glucocorticoids.

Acute-Phase Proteins↗

Inhibition of autoimmune diabetes in NOD mice with serum from streptococcal preparation (OK-432)-injected mice.

We have recently reported that systemic and chronic administration of recombinant tumour necrosis factor alpha (TNF-alpha), as well as streptococcal preparation (OK-432), inhibits development of insulin-dependent diabetes mellitus (IDDM) in NOD mice and BB rats, models of IDDM. In this study we examined whether serum containing endogenous TNF induced by OK-432 injection could inhibit IDDM in NOD mice. Treatment twice a week from 4 weeks of age with OK-432-injected mouse serum, which contained endogenous TNF (75U), but not IL-1, IL-2 and interferon-gamma (IFN-gamma) activity, reduced the intensity of insulitis and significantly inhibited the cumulative incidence of diabetes by 28 weeks of age in NOD mice, as compared with the incidence in non-treated mice (P less than 0.01) and in mice treated with control serum (P less than 0.02). This inhibitory effect of the serum was diminished, although not significantly, by neutralization of serum TNF activity with anti-mouse TNF antibody. In the mice treated with the serum from OK-432-injected mice, Thy-1.2+ or CD8+ spleen cells decreased (P less than 0.01) and surface-Ig+ (S-Ig+) cells increased (P less than 0.05), whereas the proliferative response of spleen cells to concanavalin A (P less than 0.01) and lipopolysaccharide (P less than 0.05) increased. The results indicate that the inhibition by OK-432 treatment of IDDM in NOD mice was partially mediated by serum factors including endogenous TNF.

Animals↗

Production and characterization of antibodies to ouabain.

Two monoclonal antibodies (249F8 and 278A9) to ouabain were produced by somatic cell fusion. They reacted in dose-dependent manners with ouabain and digoxin. These antibodies were supposed to recognize the partial structure important for cardiac compounds to show their pharmacological activity, Na+, K(+)-ATPase inhibition in a competitive mode against K+. These monoclonal antibodies may be useful for the immunochemical isolation, the structural elucidation, and the quantitative measurement of putative endogenous digoxin-like factors.

Animals↗

Surface characteristics of thymocytes in glucocorticoid treated rats using rosette-formation technique and surface marker analysis.

Glucocorticoid (GC) treatment is known to induce destruction of cortical thymocytes and then their reconstitution. By using the rats treated with GC, we examined the relationship between rosette-formation and surface markers (CD4 and CD8) for clarifying the processes of differentiation and maturation in rat thymocytes. Thymus weight and thymocyte count began to decrease immediately after GC administration and became minimal on 5-7 days, followed gradual recovery. The percentage of rosette-forming thymocytes began to decrease immediately after GC treatment and became minimal on 5 days, followed by recovery to the normal level by the 10th to 14th day after treatment. During the analysis of the changes in the percentage of 4 subsets (CD4-8-, CD4+8+, CD4+8+, CD4-8+) of rat thymocytes after GC treatment, the percentage of CD4+8+ cells was found to change in close relation to the change in the percentage of rosette-forming lymphocytes, suggesting that rosette-forming thymocytes are CD4+8+ cells. These results suggest that the treatment induces destruction of GC-sensitive thymocytes, possibly rosette-forming cells, followed by migration of precursor T cells (CD4-8- cells) in the thymus, and that the precursors change into rosette-forming cells (CD4+8+ cells) in the thymus, followed by differentiation and maturation into non-rosette-forming cells (CD4+8- or CD4-8+ cells).

Animals↗

Surface antigenic analysis of rosette-forming cells in rat thymus--using monoclonal antibodies against T cell surface markers.

We have assumed that rat thymocytes capable of rosette-formation with guinea pig erythrocytes were double positive (CD4+8+) cells. Therefore surface-binding erythrocytes on rosette-forming lymphocytes (RFLs), separated in highly pure state, were eliminated by a hypotonic shock. The surface markers of RFLs, without surface erythrocytes, were analyzed by flow cytometry using two kinds of monoclonal antibodies (anti-CD4, anti-CD8) labelled with different fluorescence materials. About 96.2% of cells in the RFL population were sorted in two areas, into which double positive cells were separated. This result substantiates the assumption mentioned above. It was, furthermore, discussed that the RFLs without surface erythrocytes would be one of the valuable materials for disclosing the mechanisms of differentiation and maturation from double positive thymocytes to single positive ones.

Animals↗

Changes in the amount of cytochrome P450s in rat hepatic microsomes with starvation.

The effects of starvation on the composition of 12 different cytochrome P450s in rat hepatic microsomes were studied with a specific antibody. Changes in the metabolic activity of the microsomes were studied at the same time. P450 DM (P450j) was induced 2.5-fold by a 48-h starvation and its increase reflected the increase of metabolic activity of hepatic microsomes toward aniline, 7-ethoxycoumarin, and N-nitrosodimethylamine. P450 K-5, the major renal cytochrome P450 in untreated male rat, was also induced 2.5-fold by a 48-h starvation. P450 UT-2 (P450h) and P450 UT-5 (P450g), typical male-specific forms, decreased with starvation. P450 UT-2 had high testosterone 2 alpha- and 16 alpha-hydroxylation activities. These activities of hepatic microsomes were reduced with the decrease in P450 UT-2. P450 PB-1, testosterone 6 beta-hydroxylase, was increased time-dependently by starvation. P450 UT-4 (RLM2), a minor male-specific form, was not changed by starvation. P450 PB-2 (P450k), present in both sexes, was changed little by starvation. P450 PB-4 (P450b) and P450 PB-5 (P450e) are strongly induced in rat liver by phenobarbital in coordinate fashion. Starvation increased P450 PB-4 12-fold but reduced P450 PB-5 to 22% of the control level. P450 MC-1 (P450d) was decreased by starvation. P450 MC-5 (P450c) was barely detected in control rats and was not changed by starvation. P450 IF-3 (P450a), rich in immature rats, was increased by starvation, accompanied by an increase in testosterone 7 alpha-hydroxylation activity in the hepatic microsomes. We further investigated whether new cytochrome P450s appeared upon starvation by comparison of chromatographic profiles of cytochrome P450 from starved rats with those of cytochrome P450 from control rats using HPLC. Three new cytochrome P450s were detected in the starved rats. These cytochrome P450s were purified to homogeneity. One of them was P450 DM, judging from spectral properties, catalytic activity, and the NH2-terminal sequence. The two other forms were designated P450 3b and 4b. The minimum molecular weights of P450 3b and 4b were 53,000 and 52,000, respectively, and their CO-reduced absorption maxima were at 449 and 452 nm, respectively. P450 3b metabolized aminopyrine, N-nitrosodimethylamine, 7-ethoxycoumarin, and lauric acid, but with low activity. P450 4b was efficient in lauric acid omega- and (omega-1)-hydroxylation only. The spectral properties, catalytic activity, peptide map, and NH2-terminal sequence of P450 4b agreed with those of P450 K-5. P450 3b was a new cytochrome P450, judged by these criteria.

Amino Acid Sequence↗

Detection of endotoxin antibody in long-term dialysis patients.

Endotoxins are often seen in dialysate. They are derived from Gram-negative bacteria especially Pseudomonas, E. coli and Serratia. Endotoxins are large-molecular-weight substances with an average molecular weight of 10(8). These large units can be divided into subunits down to a molecular weight of 10,000 which are thought to pass through dialyzer membranes. To investigate this, endotoxin antibody levels were measured in two groups of patients on chronic regular hemodialysis, a low-flux group using cellulosic membrane dialyzers (cuprophan and cuproammonium rayon (CAR) and a high-flux group using synthetic polymer membrane dialyzers (PMMA, EVAL). Using an ELISA based on standard endotoxin antibodies the percentages of patients in the low flux group with endotoxin antibodies were 26.9% with Cuprophan and 25% with CAR, not significantly different from a normal control group. In the PMMA and EVAL groups, it was 53.6% and 68.4% respectively. Back filtration of dialysate into blood is understood as the main reason for the entry of endotoxin in patients treated with high-flux dialyzers.

Antibodies↗

Expression of four phenobarbital-inducible cytochrome P-450s in liver, kidney, and lung of rats.

Specific antibodies were prepared against cytochromes P450 PB-1, PB-2, PB-4, and PB-5 purified from hepatic microsomes of male rats treated with phenobarbital. With these antibodies, the levels of these four cytochrome P450s in hepatic, renal, and pulmonary microsomes of male rats that were untreated, treated with phenobarbital, or treated with 3-methylcholanthrene were examined. P450 PB-1 and PB-2 were present in moderate amounts in hepatic microsomes of untreated male rats and were induced 2- to 3-fold with phenobarbital. Also, the expression of these forms was suppressed by 3-methylcholanthrene. These forms were not detected in the renal or pulmonary microsomes of untreated rats or rats treated with phenobarbital or 3-methylcholanthrene. P450 PB-4 and PB-5 were found in the hepatic microsomes of untreated male rats at a low level but were induced with phenobarbital more than 50-fold. P450 PB-4 and PB-5 were not detected in renal microsomes; only P450 PB-4 or a closely related form was present in the pulmonary microsomes of untreated male rats, and its level was not changed by phenobarbital treatment. The constitutive presence of P450 PB-4 in pulmonary microsomes was confirmed by the investigation of testosterone metabolism. Purified P450 PB-4 had high testosterone 16 alpha- and 16 beta-hydroxylation activity in a reconstituted system. The testosterone 16 beta-hydroxylation activity of hepatic microsomes was induced with phenobarbital, and more than 90% of the testosterone 16 beta-hydroxylation activity of hepatic microsomes from rats treated with phenobarbital was inhibited by anti-P450 PB-4 antibody.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Characterization of monoclonal antibodies to human interferon-gamma and their application to enzyme-linked immunosorbent assay (ELISA).

The authors obtained two mouse monoclonal antibodies, G-208 and G-166, to recombinant human interferon-gamma (rH-IFN-gamma). Immunologically, they were classified as IgG1-K subclass. G-208 neutralized the antiviral activity of natural and recombinant human IFN-gamma, but did not bind to heat-denatured rH-IFN-gamma. G-166 was able to bind to rH-IFN-gamma as well as to heat-denatured rH-IFN-gamma, but it did not bind to natural human IFN-gamma (nH-IFN-gamma). A sandwich enzyme immunoassay specific to H-IFN-gamma molecule was developed using polyclonal rabbit anti-nH-IFN-gamma antibody and G-208. This assay monitors only biologically active H-IFN-gamma molecule. Thus, this method may be used for the direct determination of H-IFN-gamma instead of determination of antiviral activity of H-IFN-gamma.

Antibodies, Monoclonal↗

Constitutive testosterone 6 beta-hydroxylase in rat liver.

The cytochrome P-450 that was purified from hepatic microsomes of male rats treated with phenobarbital and designated P450 PB-1 (Funae and Imaoka (1985) Biochim. Biophys. Acta 842, 119-132) had high testosterone 6 beta-hydroxylation activity (turnover rate, 13.5 nmol of product/min/nmol of P-450) in a reconstituted system consisting of cytochrome P-450, NADPH-cytochrome P-450 reductase, cytochrome b5, and a 1:1 mixture of lecithin and phosphatidylserine in the presence of sodium cholate. In ordinary conditions in the reconstituted system with cytochrome P-450, reductase, and dilauroylphosphatidylcholine, P450 PB-1 had little 6 beta-hydroxylase activity. The catalytic activities toward testosterone of two major constitutive forms, P450 UT-2 and P450 UT-5, were not affected by cytochrome b5, phospholipid, or sodium cholate. P450 PB-1 in rat liver microsomes was assayed by immunoblotting with specific antibody to P450 PB-1. P450 PB-1 accounted for 24.4 +/- 5.6% (mean +/- SD) of the total spectrally-measured cytochrome P-450 in hepatic microsomes of untreated adult male rats, and was not found in untreated adult female rats. P450 PB-1 was induced twofold with phenobarbital in male rats. P450 PB-1 was purified from untreated male rats and identified as P450 PB-1 from phenobarbital-treated rats by its NH2-terminal sequence, peptide mapping, and immunochemistry. These results showed that P450 PB-1 is a constitutive male-specific form in rat liver. There was a good correlation (r = 0.925) between the P450 PB-1 level and testosterone 6 beta-hydroxylase activity in rat liver microsomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗