PubMed Health⌕ Search

Biomedical subjects

M Kagami

Publications and source records attributed to M Kagami.

At least 37 records · Page 2Linked to original sources
PubMed1997

SRO9, a multicopy suppressor of the bud growth defect in the Saccharomyces cerevisiae rho3-deficient cells, shows strong genetic interactions with tropomyosin genes, suggesting its role in organization of the actin cytoskeleton.

RHO3 encodes a Rho-type small GTPase in the yeast Saccharomyces cerevisiae and is involved in the proper organization of the actin cytoskeleton required for bud growth. SRO9 (YCL37c) was isolated as a multicopy suppressor of a rho3delta mutation. An Sro9p domain required for function is similar to a domain in the La protein (an RNA-binding protein). Disruption of SRO9 did not affect vegetative growth, even with the simultaneous disruption of an SRO9 homologue, SRO99. However, sro9delta was synthetically lethal with a disruption of TPM1, which encodes tropomyosin; sro9delta tpm1delta cells did not distribute cortical actin patches properly and lysed. We isolated TPM2, the other gene for tropomyosin, as a multicopy suppressor of a tpm1delta sro9delta double mutant. Genetic analysis suggests that TPM2 is functionally related to TPM1 and that tropomyosin is important but not essential for cell growth. Overexpression of SRO9 suppressed the growth defect in tpm1delta tpm2delta cells, disappearance of cables of actin filaments in both rho3delta cells and tpm1delta cells, and temperature sensitivity of actin mutant cells (act1-1 cells), suggesting that Sro9p has a function that overlaps or is related to tropomyosin function. Unlike tropomyosin, Sro9p does not colocalize with actin cables but is diffusely cytoplasmic. These results suggest that Sro9p is a new cytoplasmic factor involved in the organization of actin filaments.

Actins↗
PubMed1996

Expression of high-affinity IgE receptor (Fc epsilon RI) on human alveolar macrophages from atopic and non-atopic patients.

The expression of high-affinity IgE receptor (Fc epsilon RI) on alveolar macrophages was examined in order to determine the association of alveolar macrophages with IgE-dependent inflammation. Immunostaining showed that a 15-1 monoclonal antibody against Fc epsilon RI alpha chain reacted with alveolar macrophages from both atopic and non-atopic patients by immunostaining. In addition, preincubation of 15-1 monoclonal antibody specifically blocked monomeric IgE binding to alveolar macrophages. Reverse transcription polymerase chain reaction showed that CD14+ alveolar macrophages expressed Fc epsilon RI alpha, beta and gamma chain mRNA. These results show that alveolar macrophages express Fc epsilon RI and may participate in IgE-dependent inflammation mediated by Fc epsilon RI.

Bronchoalveolar Lavage Fluid↗
PubMed1996

In vitro interleukin-5 (IL-5) production by peripheral blood mononuclear cells from patients with drug hypersensitivity.

It has been shown that CD4+ lymphocytes and eosinophils pathologically infiltrate the dermis in skin eruptions due to hypersensitivity to the administration of certain drugs associated with peripheral eosinophilia. However, the mechanisms involved in drug related skin eruptions with eosinophilia are largely unknown. There are several methods of diagnosing drug hypersensitivity, but no single in vitro method is available for the detection of the sensitizing drug. In order to elicit the mechanism of drug related skin eruption with eosinophilia and to establish effective methods for diagnosing drug hypersensitivity, we studied in vitro IL-5 production by peripheral mononuclear cells (PBMC) from patients with drug related skin eruptions (n = 8). Significant increase in IL-5 from exposure to drug alone (n = 3) and drug with PHA (n = 3) were noted, whereas PBMC from normal subjects (n = 7) exhibited no such stimulation. Six of the eight cases showed a significant decrease in the number of peripheral blood eosinophils when the skin eruptions healed compared with those at the onset. Histopathological features revealed mild to moderate infiltration of eosinophils. Immunohistopathologically, infiltration of CD4+ and CD8+ lymphocytes and CD4+ cells were predominant within the dermis of drug related skin eruption sites in all cases. This study suggested that the IL-5 production of sensitized mononuclear cells might be a critical mediator in drug hypersensitivity with eosinophilia and an important diagnostic marker.

Adult↗
PubMed1995

[Expression of ductal Fas antigen in sialoadenitis of Sjögren's syndrome].

The expression of Fas antigen on ductal epithelial cells of sialoadenitis was examined in patient with Sjögren's syndrome and normal subject. In two patients with severe sialoadenitis, Fas antigen was strongly expressed on the ductal epithelial cells. In contrast, Fas antigen was not seen in minor salivary gland of normal subjects and of mild sialoadenitis cases. This finding suggests that Fas antigen may play a role in the pathogenesis of sialoadenitis in Sjögren's syndrome by providing a specific target for cytotoxic T cells expressing Fas ligand.

Apoptosis↗
PubMed1995

[Immunohistochemical identification of infiltrating mononuclear cells in tubulointerstitial nephritis associated with Sjögren's syndrome].

Using monoclonal antibodies, Immunoperoxidase analysis was performed on renal biopsy samples obtained from patients with Sjögren's syndrome associated with tubulo-interstitial nephritis. In all cases the interstitial infiltrates were predominantly CD5-positive T cells (mean 66%), whereas both B cell (CD19-positive) and monocyte (CD15-positive) populations participated to a lesser degree. CD16-positive NK/K cells were rarely encountered. The CD4/CD8 ratio was consistently higher than 1.0 (mean 2.08). The lymphocyte which invaded the tubular epithelial cells to present a feature of tubulitis were CD8 positive, suggesting that they were cytotoxic T cells. These results were in general accord with those obtained in the salivary glands of patients with Sjögren's syndrome. It was thus concluded that the same immunological process was probably operative in the renal tubulointerstitial tissue as in the salivary glands to induced the characteristic tissue changes of Sjögren's syndrome.

Humans↗
PubMed1994

Chronic salicylate intoxication and rhabdomyolysis in a patient with scleroderma and Sjögren's syndrome.

A 44-year-old woman with scleroderma and Sjögren's syndrome developed altered consciousness, acute renal failure, and rhabdomyolysis. She had no history of trauma, seizures, alcohol abuse, hyperthermia, or other possible causative factors for rhabdomyolysis. A high serum salicylate level indicated a diagnosis of salicylate intoxication. Medical history after recovery revealed chronic salicylate ingestion for severe headaches. This is possibly the first reported case of rhabdomyolysis caused by chronic salicylate intoxication. Continuous hemodiafiltration early in hospitalization was an effective treatment.

Acute Kidney Injury↗
PubMed1993

[Clinical relevance on the inhibition of eosinophil functions--a review with special reference to eosinophilopietic cytokines].

Theoretical strategies for the inhibition of eosinophil function could be multistep. The pivotal role of GM-CSF, IL-3 or IL-5 in up-regulating eosinophil number and function might be specific targeting of therapy. Drugs attenuating T cells which generate those cytokines would induce a clinical remission by reducing the generation of a regulatory cytokine. Alternatively, therapies may be attained by blocking cytokine receptor binding at the level of the target stem cell or the mature eosinophil. Inhibition of eosinophil recruitment from peripheral blood to inflammatory tissue compartment will also be the site of therapy by inhibiting adhesion molecule function. Direct inhibition of chemical mediator release such as cytotoxic granular basic proteins, leukotrienes, PAF and superoxides from activated eosinophil would be another target for developing new drugs.

Animals↗
PubMed1989

Production and characterization of monoclonal antibodies to Fc gamma 2a-binding protein isolated from the detergent lysate of a murine macrophagelike cell line, P388D1.

Hybridoma cell lines were produced by fusion of SP2/0 murine myeloma cell line with the spleen cells of Wister rats which were immunized with IgG2a-binding protein isolated from the detergent lysate of a murine macrophagelike cell line, P388D1, by affinity chromatography on IgG-Sepharose 4B. A monoclonal clone (designated as 3A2) out of a total of 13 different antibody-secreting cell lines was found to secrete IgG1 class antibodies, which inhibited more than 70% of the binding of radio-iodinated myeloma IgG2a protein to P388D1 cells. The 3A2 Fab fragments bound specifically to P388D1 cells at 4 degrees C with a KD of 1.9 x 10(-8) M and Bmax of 2.9 x 10(5) per cell. This Fab fragment also specifically bound to Fc gamma 2a receptor (R)-positive T cell line (S49) with a KD of 4.4 x 10(-9) M and a Bmax of 1.0 x 10(4) but did not bind to Fc gamma 2a-negative S49 variant cell line, cyc-. The flow cytometric analysis with the use of fluorescein-isothiocyanate-tagged 3A2 F(ab')2 also showed that this antibody binds to Fc gamma 2aR-positive cells, P388D1 and S49, but not to Fc gamma 2aR-negative cells, cyc-. Monomeric and heat-aggregated IgG2a (13-fold molar excess) inhibited the binding of the radioiodinated 3A2 F(ab')2 to P388D1 cells by 70 and 49%, respectively, whereas the inhibition by monomeric and heat-aggregated IgG2b was 17 and 39%, respectively; 3A2 F(ab')2 (100-fold molar excess) inhibited the binding of IgG2a and IgG2b to P388D1 cells by 90 and 24%, respectively, whereas the inhibition of binding of these IgG to S49 cells was 79 and 49%, respectively. Western blotting analysis showed that 3A2 antibody recognizes a major protein (Mr = 100,000) and a minor component (Mr = 80,000) separated by SDS-PAGE of P388D1 or S49 cell lysates under nonreducing condition, whereas under reducing condition, this antibody recognized a major protein (Mr = 50,000) and two additional minor components (Mr = 40,000 and 35,000). Fc gamma 2aR may thus exist at the cell surface as a disulfide linked dimer of a subunit of Mr of 50,000, which could be partially degraded during the isolation to smaller fragments of 40,000 and 35,000 Mr peptides which are still held together by interchain disulfide bond.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Cytotoxic anti-lymphocyte antibody in schizophrenics.

An IgM antibody cytotoxic to normal human lymphocytes was found in 46.2% (male: 61.5%; female: 30.8%) of sera from chronic schizophrenics by means of a complement-dependent cytotoxicity test. The relationship between this antibody and the immunological manifestations of schizophrenia is discussed.

Adult↗
PubMed1987

[Immunological study of beryllium workers].

Immunological health surveys of Beryllium (Be) workers in a copper-beryllium casting factory were made 10 times during the 5-year period from 1981 to 1985. The total number of Be workers was 150. 1) Macrophage migration inhibition test was performed by an agarose plate method using Be as antigen with peritoneal cells from guinea pigs and small amounts of Be worker's blood. We found that 1 out of 22 healthy Be workers (4.5%) that migration index (MI) was below 80% after 24 h and 5 (22.7%) after 48 h. The mean of MI in Be workers showed significant low value as compared with that of the control group (p less than 0.01). 2) It was found that the serum complement titer tended to be lower in Be workers than in the control group. The serum complement titer of 3 to 6 subjects showed to be less than 30 U/ml every survey. 3) Although a few showed the abnormal levels in serum immunoglobin (IgG, IgA and IgE), the means of these immunoglobin levels were not markedly changed and they were in the normal ranges, respectively. 4) MI values significantly correlated with IgE level in Be workers, that is y= -8.9 x + 997.8 (r = -0.473, p less than 0.05). These results suggest that macrophage migration inhibition test and serum complement titer were of value for assaying of sensitivity to Be and immune responses in Be workers.

Beryllium↗
PubMed1987

Antibody to activated lymphocytes in patients with systemic lupus erythematosus.

IgG antilymphocyte antibodies preferentially reacting with phytohemagglutinin (PHA) activated peripheral blood lymphocytes (PBL) and an adult T cell leukemia cell line were detected in 70.6% sera from patients with systemic lupus erythematosus (SLE), using a fluorescence activated cell sorter (FACS). In the sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis, 2 major peaks with an apparent molecular weight 60,000 to 65,000 Da and about 40,000 Da were observed in the membrane glycoprotein fractions of both PHA activated PBL and an adult T cell leukemia cell line. From the result of sequential coprecipitation analysis of SDS-PAGE between SLE serum, antiinterleukin-2 (IL-2) receptor antibody (anti-Tac antibody) and anti-Ia antibody, the reactive antigen on the activated PBL and an adult T cell leukemia cell line proved to be an identical molecule of the IL-2 receptor on these cells. The role of this autoantibody in the modulation of T cell mediated immunity in patients with SLE is discussed.

Antilymphocyte Serum↗
PubMed1985

Antibodies to human T cell leukemia virus are absent in patients with systemic lupus erythematosus.

It has been anticipated that type C oncornaviruses, which participate in the pathogenesis of murine systemic lupus erythematosus (SLE), would be found to have a role in the development of SLE in humans. In studies of tissues from SLE patients, type C-related proteins have been identified. Using information obtained on the recent isolation of the human T cell leukemia virus (HTLV), together with that from studies of murine SLE, we attempted to clarify the role of antibodies to HTLV in the pathogenesis of human SLE. Using a solid-phase enzyme-linked immunosorbent assay and sodium dodecyl sulfate-polyacrylamide gel electrophoretic techniques, we were unable to find evidence of the participation of antibodies to HTLV proteins in the development of human SLE.

Antibodies, Viral↗
PubMed1984

[Effects of beryllium chloride on cultured cells].

The effects of beryllium on cultured cells were investigated. Three cell-lines (HeLa-S3, Vero, HEL-R66) were used in these experiments and they were cultured in Eagle's MEM plus 5 or 10% FBS (Fetal Bovine Serum) containing beryllium in various concentrations. HeLa cells or Vero cells were able to grow in the medium with 10 micrograms Be/ml (1.1 mM). On the other hand, the growth of HEL cells were strongly inhibited, even when cultured in the medium with 1 microgram Be/ml (1.1 X 10(-1) mM) and the number of living cells showed markedly low level as compared to that of the control samples cultured in the medium without beryllium. The cytotoxic effects of beryllium on these cells, which were cultured for three days in the medium with beryllium, were observed. None of cytotoxic effects were found on HeLa cells cultured with 0.5 micrograms/ml (5.5 X 10(-2) mM) and on Vero cells cultured with 0.05 micrograms Be/ml (5.5 X 10(-3) mM), while HEL cells received cytotoxic effects even when cultured in the medium containing 0.05 micrograms Be/ml (5.5 X 10(-3) mM), and these effects on the cells appeared strong when cultured in the medium without FBS. It was revealed from these experiments that HEL cells are very sensitive in terms of toxic effects of beryllium. Therefore, there cells can be used for the toxicological study on low level concentrations of the metal.

Animals↗