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Biomedical subjects

I Ohno

Publications and source records attributed to I Ohno.

At least 91 records · Page 5Linked to original sources
PubMed1991

A 3' splice site consensus sequence mutation in the intron 3 of the alpha-galactosidase A gene in a patient with Fabry disease.

Fabry disease is an X-linked disorder accompanied with accumulation of glycosphingolipids resulting from the deficient activity of the lysosomal hydrolase, alpha-galactosidase A (alpha-GalA). In the present study, mRNA for alpha-GalA in fibroblasts from an 11-year-old Japanese patient with Fabry disease was examined using the reverse transcriptase-polymerase chain reaction (PCR). The shorter message of alpha-GalA was demonstrated in this patient when compared with the normal control. The complete deletion of exon 4 in the mRNA for alpha-GalA in the patient was disclosed by analysis of cDNA with restriction enzyme digestion and asymmetrical PCR sequencing. The direct sequencing of the genomic DNA demonstrated a single base substitution (G----A) at the 3' end of the consensus sequence of intron 3. This mutation destroyed a splice site in the alpha-GalA, which produced a mutant allele. It was also shown that the mother of the patient had this mutant as well as normal alleles as a heterozygote.

Child↗
PubMed1991

Granulocyte/macrophage colony-stimulating factor (GM-CSF) gene expression by eosinophils in nasal polyposis.

Nasal polyposis is a chronic inflammatory condition of the upper airways characterized by infiltration of activated inflammatory cells, particularly eosinophils. Granulocyte/macrophage colony-stimulating factor (GM-CSF) is a cytokine with powerful biologic effects including the regulation of survival, proliferation, and activation of granulocytes as well as differentiation of hemopoietic cells. To examine the potential role of GM-CSF in the pathogenesis of this condition, we investigated gene expression and production of GM-CSF in nasal polyp tissues as well as in the normal nasal mucosa. Immunoreactive GM-CSF was detected by enzyme-linked immunosorbent assay in the 24-h supernatant of nasal polyp tissues placed in culture. By Northern blot analysis and Southern blot analysis following a reverse-transcription polymerase chain reaction using a human GM-CSF cDNA probe, we detected GM-CSF mRNA in nasal polyp tissues, as well as in the tissue from a patient with allergic rhinitis, but not in the normal nasal mucosa. By in situ hybridization using the same probe, cells expressing mRNA specific for GM-CSF were observed in nasal polyp tissues and in the allergic nasal mucosa. In addition, by the combination of in situ hybridization and counterstaining with chromotrope 2R, we demonstrated that approximately 30% of eosinophils infiltrating the polyp tissue express the GM-CSF gene. These results suggest a novel mechanism by which eosinophils may contribute to the pathogenesis of chronic inflammatory diseases such as nasal polyposis, allergic rhinitis, and, by implication, asthma.

Base Sequence↗
PubMed1991

[Intravenous cyclophosphamide therapy in patients with steroid-resistant lupus nephritis].

We evaluated short term clinical effects of intravenous cyclophosphamide (iv CyP) therapy performed by every three month in 7 patients with steroid-resistant lupus nephritis. Significant improvements were observed in daily urinary protein excretion (3.1 to 0.83 g/day), creatinine clearance (65.4 to 95.3 ml/min), CH 50 levels (20.8 to 37.4 U/ml), and anti-DNA antibody titer (26.6 to 7.0 U/ml). In addition, the mean daily dose of prednisolone (PSL) could be markedly reduced from 38.6 mg to 13.9 mg at the final observation. Two patients suffered from Herpes Zoster infection at a few months after ivCyP therapy, however this incidence were not considered as critical side effect which reached to the discontinuation of this therapy. We concluded that ivCyP therapy by every three months were safety and achieved beneficial clinical effects on steroid-resistant lupus nephritis as far as short observation. On the contrary, the long term effect of this mode of therapy is to be defined.

Administration, Oral↗
PubMed1991

Soluble IL-2 receptor in patients with primary nephrotic syndrome.

The soluble interleukin-2 receptor (SIL-2R) levels in 46 patients with primary nephrotic syndrome were examined. The values in the nephrotic patients exceeded those in healthy controls (p less than 0.05), and were the same at the nephrotic and non-nephrotic stages. The serum interleukin-2 (IL-2) levels in the nephrotic patients were low and did not correlate with the serum SIL-2R levels. Only at the nephrotic stage were the latter closely correlated with the serum IgG (p less than 0.001) but not with the serum IgA or IgM. The SIL-2R production by phytohemagglutinin stimulated peripheral blood lymphocytes (PBL) in the nephrotic patients was less at the nephrotic and non-nephrotic stages than that in the healthy controls. The IgG production by pokeweed mitogen stimulated PBL was low at the nephrotic stage but not at the non-nephrotic stage. Based on these findings, it is suggested that SIL-2R determinations should prove useful in clarifying the relationship between cellular and humoral immunological disorders in nephrotic syndrome.

Adult↗
PubMed1991

Characterization of acute renal failure due to primary nephrotic syndrome.

Acute renal failure (ARF) associated with primary nephrotic syndrome (PNS) was analyzed clinically in order to evaluate the mechanism of onset. The incidence of induced ARF with PNS was found to be cases (2.1%) out of 420 cases attending our outpatient clinic. The renal histological changes included 2 cases of minimal change nephrotic syndrome (MCNS), 6 of focal glomerular sclerosis (FGS) and one of unknown origin. The 6 cases which recovered from ARF were designated as group A. The 3 cases of group B required maintenance dialysis; they included one case of MCNS, one of FGS and one of unknown origin, and showed resistance to aggressive treatments, such as steroid pulse therapy, anticoagulants and plasmapheresis. In the patients of group A, follow up studies for 10 years confirmed that their condition was not progressive. There were no significant differences between the reversed group A cases recovering from ARF and the non-reversed group B cases in terms of their clinical parameters, such as age, sex, urinary protein excretion, initial renal function, blood pressure, renal histological damage and complications. Specific factors associated with the induction of reversibility from ARF could not be identified. Further research is needed to elucidate the precise characteristics of the ARF occurring in PNS.

Acute Kidney Injury↗
PubMed1990

Reversal of methotrexate cytotoxicity to human bone marrow cells and leukemic K562 cells by leucovorin: methotrexate polyglutamates formation as a possible important factor.

Methotrexate (MTX) is metabolized intracellularly to MTX-polyglutamates (MTX-PGs), which markedly inhibit several folate-dependent enzymes. Polyglutamation defect, therefore, is one of the important factors in drug resistance. In this study, reversal of MTX cytotoxicity by l-leucovorin (l-LV) was investigated using normal human bone marrow granulocyte progenitor cells (G-CFCs), and MTX-sensitive and -resistant leukemic K562 cell lines; the latter showed diminished polyglutamation. Cytotoxicity of 10(-7)M MTX to G-CFCs was completely reversed by an equimolar concentration of l-LV, but with higher MTX concentrations, relatively more l-LV was required. The reversal of MTX cytotoxicity by l-LV was more effective against bone marrow cells than MTX-sensitive K562 cells; this reversal seemed to be correlated to the total intracellular MTX levels as well as MTX-PG formation (low in bone marrow cells and high in K562 cells). When MTX-sensitive and -resistant K562 cells were incubated with MTX under conditions in which the total intracellular MTX levels of both cells were similar, successful reversal of MTX toxicity by l-LV was demonstrated in MTX-resistant cells, but not in MTX-sensitive cells, suggesting that an increase of MTX-PG formation in MTX-sensitive cells may explain the failure of l-LV to overcome MTX cytotoxicity. In addition to competitive reversal of MTX cytotoxicity by LV, noncompetitive reversal relating to variable formation of MTX-PGs is suggested to be another important factor in the mechanism of the reversal of MTX cytotoxicity by LV.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1990

Production of tumor necrosis factor with IgE receptor triggering from sensitized lung tissue.

Mast cells and basophils have been known to play a central role in allergic inflammation through the release of chemical mediators by cross-linkage of IgE receptors. The IgE receptor triggering and calcium ionophore A23187 have also been shown to induce gene expression and production of tumor necrosis factor (TNF) by rat basophilic leukemia cells. In the present study, we examined whether IgE receptor triggering could induce gene expression and production of TNF in rat lung tissue. The lung tissue released not only histamine but also cytotoxic activity on L929 cells 2 and 4 h after incubation with dinitrophenyl conjugated to ovalbumin (DNP-OVA) following passive sensitization with anti-DNP monoclonal rat IgE antibody, whereas neither DNP-OVA nor anti-DNP IgE antibody could induce the cytotoxic activity when used solely. Calcium ionophore A23187 also could induce both histamine release and cytotoxic activity. These activities induced by IgE receptor triggering, A23187, and lipopolysaccharide were completely neutralized by preincubation with anti-mouse TNF-rabbit serum, but not with normal rabbit serum. Northern blot analysis using cDNA probe of mouse TNF demonstrated expression of TNF gene as early as 2 h after IgE receptor triggering. These data demonstrating that IgE receptor triggering induced gene expression and production of TNF in lung tissue suggest the participation of TNF in the pathogenesis of late asthmatic response through its biologic activities such as the attraction and activation of neutrophils and eosinophils.

Animals↗
PubMed1990

Antibodies to interleukin 2 in sera of autoimmune-prone mice.

Autoimmune-prone mice spontaneously develop the disease characterized by autoantibodies to a wide variety of antigens. In the present study, we have demonstrated that IgG antibodies to interleukin 2 (IL-2) are to be found in serum of autoimmune mice in association with ageing. These antibodies can neutralize the biological activity of IL-2 and thus play an important role in the etiopathogenesis of autoimmune disease.

Aging↗
PubMed1990

Antagonistic effects of interleukin 6 and G-CSF in the later stage of human granulopoiesis in vitro.

The effect of recombinant human interleukin 6 (rhIL-6) on the in vitro growth of human bone marrow myeloid progenitors (granulocyte-macrophage colony-forming units, CFU-GM) was investigated. Recombinant human IL-6 by itself did not induce colony formation. When rhIL-6 at various concentrations was added to the CFU-GM colony cultures containing recombinant human granulocyte colony-stimulating factor (rhG-CSF) or recombinant human granulocyte-monocyte/macrophage colony-stimulating factor (rhGM-CSF), rhIL-6 significantly suppressed the colony formation induced by rhG-CSF, but not by rhGM-CSF. This suppressive effect of rhIL-6 on rhG-CSF-induced, but not rhGM-CSF-induced colony formation was confirmed by using an MY10(+)-cell-enriched population. Neither interleukin 3 nor interleukin 1 alpha suppressed the growth of myeloid progenitors. The preincubation of bone marrow cells with rhIL-6 for a short time (30 min) resulted in a reduction of colonies induced by rhG-CSF, but not by rhGM-CSF. The suppressive effect of rhIL-6 on rhG-CSF-induced colony formation was not observed when the cells were preincubated together with rhG-CSF at a high ratio of rhG-CSF to rhIL-6. The rhIL-6-mediated suppressive effect was further confirmed by blocking the effect by the anti-IL-6 antibody. These results suggest antagonistic interaction between IL-6 and G-CSF in the later differentiation of myeloid progenitors.

Adult↗
PubMed1990

Production of tumour necrosis factor by mastocytoma P815 cells.

P815, a transformed mouse mastocytoma cell line, produced and released cytotoxic factors after stimulation with phorbol 12-myristate 13-acetate (PMA), but not with lipopolysaccharide (LPS), calcium ionophore A23187 and IgE receptor triggering. The cytotoxic activity was reduced 60% by antibodies to mouse tumour necrosis factor (TNF). In addition, we demonstrated that TNF mRNA was already expressed under normal culture conditions and that it increased after stimulation with PMA. Although it was unknown whether factors other than TNF were lymphotoxin or some other unknown factors, it has been suggested that mast cells have cytotoxic activity, and that they contribute to inflammatory response through the release of TNF, which has a wide range of biological activity.

Animals↗
PubMed1990

Gene expression and production of tumour necrosis factor by a rat basophilic leukaemia cell line (RBL-2H3) with IgE receptor triggering.

This study evaluated the gene expression of tumour necrosis factor (TNF) and the molecular weight of the cytotoxic factor in a subline of a rat basophilic leukaemia cell line, RBL-2H3. After IgE receptor triggering with a specific antigen that was associated with histamine release, cytotoxic activity in the cell lysates and supernatants increased for 2 hr during the culture of RBL-2H3 cells. Furthermore, calcium ionophore A23187 could induce release of histamine and cytotoxic activity from RBL-2H3 cells. However, compound 48/80, lipopolysaccharide (LPS) and phorbol 12-myristate 13-acetate (PMA) were unable to induce the release of either histamine or cytotoxic activity from the cells. These data suggested that, at least in part, there was a common pathway in histamine release and production of cytotoxic activity. A protein synthesis inhibitor, cycloheximide, did not affect histamine release, but inhibited the induction of cytotoxic activity. This cytotoxic activity from RBL-2H3 cells was completely neutralized by anti-mouse TNF rabbit serum. With Northern blot analysis, mouse TNF cDNA probe could hybridize with RNA isolated from RBL-2H3 cells. TNF mRNA was induced as early as 1 hr after stimulation with specific antigen and decreased by 4 hr. Moreover, the molecular weight (MW) of the released cytotoxic factor from RBL-2H3 cells triggered with IgE receptors was approximately 17,000 by SDS-PAGE, which was compatible to that of TNF. Thus, it is concluded that the gene expression and production of TNF occurred in RBL-2H3 cells after IgE receptor triggering in association with histamine release, suggesting that TNF produced by basophils and mast cells may play an important role in allergic reaction through its wide range of biological activity.

Animals↗
PubMed1990

[Detection of Epstein-Barr virus specific IgE antibody].

To confirm the existence and investigate the biological significance of IgE virus-specific antibodies, we studied Epstein-Barr virus (EBV)-specific IgE antibody by enzyme-linked immunosorbent assay with an anti human IgE monoclonal antibody. We detected EBV-specific IgE antibody in sera not only from patients with the EBV associated diseases of infectious mononucleosis and nasopharyngeal carcinoma, but also from patients with bronchial asthma, collagen disease and healthy volunteers. However, there was no significant difference in the titers of IgE antibody specific for EBV among these groups. No significant relationship between the titers of EBV-specific IgG and IgE antibody, or between the titers of EBV-specific IgE and the total IgE levels in the sera was observed.

Adolescent↗
PubMed1990

Immune status in two brothers with Omenn's syndrome: no discernible chimerism on FACS analysis using a monoclonal antibody specific for a maternally restricted HLA antigen.

Sequential immunologic examinations, including lymph node biopsies, in two brothers with clinical characteristics of Omenn's syndrome are presented in this study. Although the number of circulating T cells with mature phenotype (OKT3+, TCR1+) was within normal range, the lymphocyte proliferative response to mitogens was poor. Examinations of the lymph nodes revealed marked lymphoid depletion associated with eosinophilic infiltration and reticular cell proliferation. Over the clinical course of 5 months, circulating T cells also mostly disappeared. Thymic hypoplasia was noted at autopsy. Although intrauterine graft-versus host disease (GVHD) has been hypothesized as being the pathogenetic mechanism in this syndrome, maternal lymphocytes circulating in these patients were not identified either by karyotype and HLA typing or by highly sensitive FACS analysis and immunohistochemical studies using a monoclonal antibody, HLA-A9, specific for a maternally restricted HLA antigen, Aw24. In conclusion, the familial occurrence and the absence of maternal chimerism might be the essential features of Omenn's syndrome which should be differentiated from fetal GVHD.

Antibodies, Monoclonal↗
PubMed1990

[Allopurinol induced aplastic anemia in a patient with chronic renal failure].

A 43 year old female patient with chronic renal failure originated from polycystic kidney disease was admitted with pancytopenia. Prior to the admission, she had a history of taking allopurinol for 3 months. Allopurinol was discontinued immediately and she was treated with blood transfusion (platelet and RBC) and fluoxymesterone. The lymphocyte stimulation tests were negative for allopurinol and oxipurinol. The determination of serum levels of allopurinol and oxipurinol was disclosed to be not so high compared with other patients treated with allopurinol. On 45th day after admission, she was transfused with bone marrow from her elder brother. Thereafter bone marrow finding of the patient began to improve despite the lack of bone marrow engraftment. For further improvement, pulse treatment with corticosteroid was carried out. Although the pathophysiology of allopurinol-induced aplastic anemia remains unknown, it is interesting to note that bone marrow transfusion and pulse treatment with corticosteroid seemed effective in this case.

Adult↗
PubMed1989

Fc receptors for IgE (Fc epsilon R) on human lymphoid cells: inducible expression of Fc epsilon RII (CD23) on lymphocytes and detection by monoclonal anti-Fc epsilon RII antibody.

The studies presented herein describe (1) a sensitive, quantitative, and objective assay for detecting cell membrane-bound form of Fc receptors for IgE displayed on human lymphoid cells based on measuring unlabeled Fc epsilon R-bound IgE by a solid-phase RIA of cell lysate fluids; (2) the development and characterization of an IgM monoclonal antibody, termed 7E4, which is specific for human lymphocyte Fc epsilon RII (CD23) molecules; and (3) a system for reproducibly inducing de novo synthesis and expression of Fc epsilon RII proteins on human lymphocytes following exposure to the mitogenic lectin, pokeweed mitogen. The Fc epsilon RII molecules induced by exposure to PWM were proven to be present on lymphocytes, and not on other cell types in several ways, including (1) documenting sensitivity of such proteins to both acid pH and trypsin treatment, the latter manipulation being ineffective in removing Fc epsilon RII molecules on basophils and mast cells; (2) demonstrating specific reactivity of the expressed Fc epsilon RII molecules with the 7E4 monoclonal antibody, which is specific for human lymphocyte Fc epsilon RII molecules and does not react with Fc epsilon R molecules on other cell types; and (3) observing the required concomitant presence of both T and B lymphocytes during the induction process and proving that the induced Fc epsilon R+ cells are indeed B cells of the Leu-12+ phenotype by fluorescence analysis. The ability to induce expression of Fc epsilon RII molecules on human lymphocytes exposed to a mitogen such as PWM requires special technical attention to the method of preparation and isolation of human lymphoid cells from peripheral blood. This in vitro system for up-regulating Fc epsilon RII expression on human lymphocytes should provide us with an important new tool to analyze the participation of such cells in the regulatory mechanisms controlling the human IgE antibody system.

Animals↗
PubMed1989

Production of interleukin 1-like factor from human peripheral blood monocytes and polymorphonuclear leukocytes by superoxide anion: the role of interleukin 1 and reactive oxygen species in inflamed sites.

In the present study, we investigated the possibility that oxidative stress to human peripheral blood monocytes and polymorphonuclear leukocytes (PMNs) can induce interleukin 1 (IL-1)-like activity. Oxidative stress that we used was superoxide anion (O2-) and hydrogen peroxide (H2O2). O2-, but not H2O2, could induce an IL-1-like factor(s) from monocytes and PMNs. IL-1-like activity from monocytes and PMNs induced by O2- was due to de novo synthesis because no IL-1-like activity was found in culture supernatants and in the lysate of unstimulated cells. We next examined the effects of radical scavengers on production of an IL-1-like factor(s). Generation of IL-1-like activity from monocytes was amplified by preincubation with catalase (H2O2 scavenger), although it was suppressed by preincubation with either superoxide dismutase (O2- scavenger) or vitamin E (antioxidant analogs). These results suggest that production of an IL-1-like factor(s) from monocytes and PMNs was due to O2- stimulation. Our data that production of an IL-1-like factor(s) from inflammatory cells by stimulation with O2- imply a model of the up-regulation mechanism of inflammation mediated by enhanced IL-1-like factor production stimulated with reactive oxygen species.

Glucose Oxidase↗
PubMed1989

Altered immune responsiveness in patients with chronic glomerulonephritis.

In order to detect abnormalities in humoral immunity and to determine immunogenetic traits underlying chronic glomerulonephritis, sera from 260 patients who had chronic glomerulonephritis and who were undergoing hemodialysis were tested for naturally occurring antibodies against mycoplasma and 22 different viruses. Among the 23 microorganisms tested, antibody titers were significantly lower against 12, higher against 3, and no different against 8 when compared with titers of 43 normal subjects. The data were analyzed further by plotting each in a 23-dimensional space according to their standardized antibody titers. Multivariate cluster analysis by the Ward's method revealed 3 large clusters differing from each other in natural antibody titers, and one of the clusters included 74% of the normal controls, while two other distinct clusters comprised the majority of the patients. The level of BUN, creatinine, and duration of hemodialysis treatment did not differ significantly among patients in these three different clusters. Our study suggests that patients with chronic glomerulonephritis being treated by hemodialysis have altered levels of naturally occurring antibodies to microorganisms. This alteration is not caused by just the uremic state or hemodialysis but immunogenetic regulation may also play a part.

Adolescent↗