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Biomedical subjects

M Kawagoe

Publications and source records attributed to M Kawagoe.

At least 19 recordsLinked to original sources

An ultrasensitive system to detect IL-4: enzyme-linked immunosorbent assay (ELISA) combined with an avidin-biotin and enzyme amplification system.

We established an ultrasensitive interleukin-4 enzyme-linked immunosorbent assay by combining ELISA with an avidin-biotin and enzyme amplification system. The resultant system (AB-EA ELISA) was 250 times more sensitive than conventional ELISA and 2.5 times more sensitive than enhanced ELISA using an enzyme amplification system alone. The ultrasensitive assay was specific to IL-4 alone; there was no cross reaction with other cytokines. Using the ultrasensitive assay, we measured IL-4 synthesis in vitro by unstimulated and stimulated peripheral blood mononuclear cells (PBMC) from patients with allergic rhinitis. PBMC from patients spontaneously produced measurable amounts of IL-4, whereas IL-4 production from PBMC of normal controls, if any, was below detectable levels. Stimulation of the cultures with LPS significantly increased IL-4 production in two of six patient PBMC cultures but in none of the control cultures; stimulation with Con A markedly increased IL-4 production in all patient PBMC cultures but in only two of seven control cultures. These results suggest that the AB-EA ELISA is a useful method to study the mechanism of IL-4 synthesis in type-I allergic diseases.

Animals

Increased interleukin 1 receptor, type I, at messenger RNA and protein level in skin fibroblasts from patients with systemic sclerosis.

Summary. To elucidate the mechanisms of the fibrosis in systemic sclerosis (SSc) through the action of a cytokine, interleukin 1 (IL-1), we studied the specific biologic and biochemical features of interleukin 1 receptor (IL-1R) as expressed on the surfaces of fibroblast cells in cultures from 3 SSc patients and 3 normal donors. 125I-IL-1 beta binding assays revealed a high density of IL-1R on the cell surfaces of SSc fibroblasts as compared to those of normal subjects. We also found an enhanced expression of IL-1R messenger RNA (mRNA) in SSc fibroblasts, using Northern blot or slot blot analysis. These findings indicate that the expression of IL-1R on SSc fibroblasts were spontaneously induced at the transcriptional level. It is suggested that SSc fibroblasts are more sensitive to IL-1, and that the signal transduction of IL-1 through IL-1R may be eventually involved in the fibrosis of SSc.

Cells, Cultured

Autostimulatory effects of IL-6 on excessive B cell differentiation in patients with systemic lupus erythematosus: analysis of IL-6 production and IL-6R expression.

Introducing avidin-biotin complex ELISA for anti-DNA antibody, the mechanism of in vitro production of anti-ssDNA antibody as well as of polyclonal immunoglobulin mediated by an IL-6-IL-6R loop was studied in patients with systemic lupus erythematosus (SLE). Regardless of the presence or absence of T cells, B cells from SLE patients could produce IgG anti-ssDNA antibody as well as total IgG without any stimulation. Low density B cells obtained by Percoll gradient density centrifugation responded to rIL-6 to produce IgG and IgG anti-ssDNA antibody. rIL-2 and rIL-4 had lesser effects on the differentiation of low density B cells. In fact, IL-6R was preferentially expressed on low density B cells from active SLE patients, as detected by anti-IL-6R MoAb, MT18, which did not inhibit IL-6 binding. SLE B cells, especially high density B cells, produced greater amounts of IL-6 in culture supernatants than did T cells, regardless of whether disease was active or inactive. Normal T cells and B cells did not produce significant amounts of IL-6. Thus, endogenous IL-6 produced by high density B cells bound to the IL-6R preferentially expressed on the low density B cells, and drove them into terminal differentiation, especially in active SLE patients. Further, addition of polyclonal anti-IL-6 or anti-IL-6R MoAb (PM1), which inhibited IL-6 binding, both inhibited IgG anti-ssDNA antibody as well as total IgG production by SLE B cells in a dose-dependent manner. These results suggest that interruption of the autocrine IL-6 loop would be of therapeutic value in SLE.

Antibodies, Antinuclear

IL-4 down-regulates the surface expression of CD5 on B cells and inhibits spontaneous immunoglobulin and IgM-rheumatoid factor production in patients with rheumatoid arthritis.

There is evidence to suggest that CD5+ B cells may be associated with autoimmunity, e.g. they are increased in patients with rheumatoid arthritis (RA). In this study, we found that the expression of CD5 on RA B cells increased spontaneously, following culture for up to 4 days in vitro in the absence of T cells, supporting the idea that the CD5+ B cell possesses distinctive features. The spontaneous increase of CD5 expression was down-regulated by recombinant IL-4 (rIL-4). Other cytokines studied (rIL-1 alpha, rIL-2, rIL-5, rIL-6) did not alter CD5 expression. Studies of antibody production showed that rIL-4 could reduce spontaneous production of total IgG and IgM in non-stimulated RA T plus B cell cultures. Spontaneous production of IgM rheumatoid factor (IgM-RF), measured by a newly developed avidin-biotin complex ELISA, was also reduced by rIL-4. Furthermore, rIL-4 reduced the increase in IgM-RF production observed on stimulation with Staphylococcus aureus Cowan I (SAC) or pokeweed mitogen (PWM). Thus, IL-4 might act as a regulator of the development of abnormal B cell differentiation in patients with RA.

Adult

Fluorescent probe-labeled lipid microsphere uptake by human endothelial cells: a flow cytometric study.

Lipid microspheres have been used as carriers of drugs such as prostaglandin E1 (lipo-PGE1) and corticosteroid (liposteroid). Lipo-PGE1 is used for the treatment of chronic arterial occlusive diseases because its activity is far greater than that of free PGE1 in vivo. To verify the fact that the drug carriers, lipid microspheres, are preferentially taken up by endothelial cells, we labeled lipid microspheres with a fluorescent probe, DiI (DiI-LM), and observed them in some in vitro models. Stoichiometric fluorescence was obtainable, and the fluorescence was stable between pH 3.3 and pH 8.9. Human umbilical vein endothelial cells and cells of a human endothelial cell line, ECV304, showed increased uptake of DiI-LM, 81% and 61%, respectively. In contrast, uptakes were less than 7% in human skin fibroblasts, 3T3 cells, and human neutrophils. Prominent perinuclear fluorescence was also observed in endothelial cells by fluorescence microscopy. DiI-LM and flow cytometric analysis will be useful for studies to elucidate the precise mechanism of the selective accumulation of lipid microspheres by cells in blood vessel walls.

Carbocyanines

Cytokine regulation of prolyl 4-hydroxylase production in skin fibroblast cultures from patients with systemic sclerosis: contribution to collagen synthesis and fibrosis.

Prolyl 4-hydroxylase (PH) is an enzyme that catalyzes an essential step in procollagen synthesis. PH production, as measured by the new ELISA method, was significantly higher in fibroblast cultures from patients with systemic sclerosis (SSc; N = 7) than in cultures from healthy controls (NC; N = 5) (p less than 0.01). Transforming growth factor-beta and tumor necrosis factor-alpha significantly increased PH production, but recombinant interferon-gamma had a significant negative effect on PH production. Since the production of PH is relevant to collagen synthesis by fibroblasts of patients with SSc, regulation of PH production may have therapeutic value.

Cells, Cultured

Plasma thrombomodulin and alpha 2-plasmin inhibitor-plasmin complex are elevated in active systemic lupus erythematosus.

Plasma levels of thrombomodulin and alpha 2-plasmin inhibitor-plasmin complex were measured by ELISA in patients with rheumatic diseases. Thrombomodulin levels in patients with active systemic lupus erythematosus (SLE) were significantly higher than those in patients with inactive SLE or in healthy controls. This suggests that thrombomodulin, normally a component of vascular endothelial cell membrane, is easily released to plasma in patients with active SLE. High titers of the thrombomodulin level and the correlated alpha 2-plasmin inhibitor-plasmin complex elevations imply vascular injury, and consequently, excessive fibrinolytic processes in active SLE.

Adolescent

Effect of prolyl 4-hydroxylase inhibitor on fibroblast collagen production in vitro: an approach to the treatment of systemic sclerosis.

Prolyl 4-hydroxylase (PH), which catalyzes the conversion of prolyl residues to 4-hydroxyproline, plays a central role in the synthesis and secretion of collagen. We demonstrated that fibroblasts from patients with systemic sclerosis produced significantly more PH than those from healthy subjects. To regulate excessive collagen production by scleroderma fibroblasts, we examined the effect of a PH inhibitor on collagen production by scleroderma fibroblasts. Fibrostatin-C, a PH inhibitor, significantly decreased the amount of procollagen (type I) production by scleroderma fibroblasts (p < 0.01). We suggest that this PH inhibitor might be a valid antifibrotic agent useful for the treatment of patients with scleroderma.

Blotting, Northern

[An autopsy case of malignant rheumatoid arthritis (MRA) which was difficult to distinguish from polyarteritis nodosa (PN)].

We encountered a patient who was diagnosed as rheumatoid arthritis (RA) at 15 years old and developed malignant RA (MRA) within one year. He suffered from mononeuritis multiplex and cutaneous infarction. Despite of treatment including steroid pulse therapy, neuritis progressed. Lung infiltration, pancreatitis and intestinal bleeding were accompanied. He died of disseminated intravascular coagulation on 153 days after admission. Autopsy revealed systemic rheumatoid vasculitis in coronary artery, pancreas, liver, small and large intestine, kidney and lung. These severe vasculitis occurred in young RA patient are rare case and it is important to consider the therapy and prognosis.

Adolescent

Spontaneous reflex sympathetic dystrophy (Sudeck's atrophy) syndrome associated with idiopathic thrombocytopenia.

A 37-year-old woman developed reflex sympathetic dystrophy (RSD) (Sudeck's atrophy) syndrome in the right foot. Simultaneously, she had idiopathic thrombocytopenia. There was no history of injury or bone fracture before onset of RSD. Spontaneous RSD associated with idiopathic thrombocytopenia has rarely been described. A possible relationship between the 2 conditions is discussed.

Adult

[A case of antiphospholipid syndrome associated with left subclavian artery thrombosis and left external iliac vein thrombosis].

Arterial thrombosis is one of the major symptoms of antiphospholipid syndrome (APS). However, thrombosis in a primary branch of the aorta has rarely been reported in APS. We report here a case of APS complicated by thromboses in both the left subclavian artery and the left external iliac vein. A 32-year-old woman was admitted in May, 1990 complaining of no pulse in the left superficial arteries (e.g., left radial artery) for the past 5 years and acute swelling of the left lower extremity. A left ascending phlebography showed an occlusion of the external iliac vein and arteriography revealed obstruction in the left subclavian artery. Collateral circulations were developed at the site of each thrombus. Clotting and immunological studies revealed a prolonged APTT, a high titer of anticardiolipin antibody and lupus anticoagulant positive. We ruled out various diseases and clinical risk factors predisposing to both arterial and venous thromboses. Accordingly, we concluded that both thromboses were based on APS. Following treatment with anticoagulants, aspirin and corticosteroid, the swelling of her left thigh was diminished and the antibody titer was decreased within 3 months.

Adult

[Detection of intracranial lesions of rheumatoid vasculitis with magnetic resonance imaging (MRI)].

Vasculitis in malignant courses of rheumatoid arthritis is found in many systems, but rarely in the central nervous system. It has been reported that magnetic resonance imaging (MRI) is capable of depicting minute infarctions and/or lesions of demyelination more clearly than does X-ray computed tomography (CT). In the present study, we compared MRI and/or CT of the brain in 3 cases with rheumatoid vasculitis to gauge their relative usefulness for detecting cerebrovascular damages in such patients. In one case with focal neurological symptoms (case 1), MRI depicted lesions responsible for the symptoms more clearly than did CT. In the other two cases (cases 2 and 3), which had no neurological nor psychiatric symptoms, MRI detected multiple microinfarcts in each brain; CT revealed no such lesions. These results indicate that MRI may be more useful than CT to detect brain lesions in patients with rheumatoid vasculitis, and that patients with rheumatoid vasculitis who show no CNS symptoms may in fact still have cerebrovascular lesions. Further studies with MRI in more patients with rheumatoid vasculitis should establish the incidence of cerebrovascular involvement such patients; it is probably much higher than has been previously reported.

Aged

Continuous removal of anti-DNA antibody, using a new extracorporeal immunoadsorption system, in patients with systemic lupus erythematosus.

We performed selective and continuous immunoadsorption of anti-DNA antibodies from the blood of 6 patients with systemic lupus erythematosus, using a newly developed extracorporeal immunoadsorption system equipped with twin dextran sulfate-cellulose columns with an automated regenerating unit. Levels of anti-DNA, which were initially high, were rapidly diminished after 2-4 apheresis procedures in each patient; in 3 patients with proteinuria and 4 patients with lymphocytopenia, these symptoms also improved. Analysis of the kinetics and the adsorbed amounts of anti-DNA during the apheresis indicates that both the intravascular and the extravascular pool of anti-DNA are reduced with this potent apheresis technique.

Adult

Comparative effects of N,N-disubstituted dithiocarbamates on excretion and distribution of cadmium in mice.

Sodium N-benzyl-D-glucamine dithiocarbamate (BGD), sodium N-p-hydroxymethylbenzyl-D-glucamine dithiocarbamate (HBGD), sodium N-p-carboxybenzyl-D-glucamine dithiocarbamate (CBGD) and sodium N-p-methoxybenzyl-D-glucamine dithiocarbamate (MeOBGD) were evaluated for their efficacy in the distribution and excretion of cadmium in mice exposed to cadmium. Mice were injected i.p. with 109CdCl2 (1 mg Cd/kg and 74 kBq of 109Cd/animal) and 30 min or 24 h later, they were injected with chelating agents (400 mumol/kg). At 30 min after treatment with cadmium, these chelating agents all significantly enhanced the biliary excretion of cadmium, and HBGD and CBGD significantly increased the urinary excretion of the metal. At 24 h after cadmium injection, BGD, HBGD, and MeOBGD significantly increased the biliary excretion of cadmium and HBGD was the most effective on the biliary excretion of the metal. These chelating agents were effective in mobilizing cadmium from the liver at 30 min after cadmium treatment. At 24 h after cadmium treatment, HBGD and MeOBGD effectively depressed cadmium content in the liver and only HBGD among these chelating agents significantly reduced the cadmium content in the kidney. In another experiment, mice were injected i.p. with 109CdCl2 and three days later, they were injected with chelating agents every other day for 2 weeks. HBGD was the most effective on the fecal and urinary excretions of cadmium. The hepatic cadmium content was decreased after HBGD or MeOBGD injection. The injection of HBGD caused a much greater decrease in renal cadmium content than did BGD, CBGD, or MeOBGD. The results of this study indicated that the injection of HBGD to mice pretreated with cadmium can remove cadmium from the body, mainly through fecal excretion, without redistribution of cadmium to other tissues such as the brain, testes, and heart, more effectively than that of BGD, CBGD, or MeOBGD.

Animals

Interleukin 5 up-regulates high-affinity interleukin 2 receptor expression by human resting peripheral T cells: a comparison with the effect of interleukin 4 on B cells.

The separate regulation mechanisms of cytokines on two classes of interleukin 2 receptors (IL-2R) on human peripheral T and B cells were analyzed by a flow cytometer using a double stain with IL-2R alpha (55 kilodalton Tac) and IL-2R beta (75 kilodalton mik beta 1, mik beta 3). Although the expression of IL-2R alpha by T cells was slightly enhanced by IL-2 and IL-4, expression of the beta chain was diminished by both cytokines. IL-5 by itself did not alter the expression of either IL-2R alpha or beta, but preculturing with IL-2 for 24 h followed by IL-5 for another 24 h induced an increase in IL-2R alpha expression and in simultaneous alpha/beta chain expression. Increased numbers of high-affinity IL-2R were confirmed by 125I binding assays. On B cells, IL-4 increased alpha, beta, and simultaneous alpha/beta chain expression, but IL-4-treated B cells did not show an increased number of high-affinity IL-2R.

B-Lymphocytes

Complete nucleotide sequence of the gene for a surface protein antigen of Streptococcus sobrinus.

The complete nucleotide sequence of the gene for a cell surface protein antigen (SpaA) of Streptococcus sobrinus MT3791 (serotype g) was determined. The spaA gene consisted of 4,698 bp and coded for a protein of 170,202 Da. A putative signal peptide was found in the amino-terminal end of the protein. A potential promoter sequence and a putative Shine-Dalgarno sequence preceded the open reading frame. Two internal repeating amino acid sequences were present in SpaA. One repeating region, located in the amino-terminal region, was rich in alanine, and the other, located in the central region, was rich in proline. The molecular structure of SpaA was very similar to that of the surface protein antigen of Streptococcus mutans.

Amino Acid Sequence

Flow cytometric analysis of lipid droplet formation in cells of the human monocytic cell line, U937.

Active uptake of a free fatty acid, oleate, and its incorporation into triacylglycerol and phospholipid in the human monocytic cell line, U937, was identified using 14C-labelled oleate. Excess triacylglycerol accumulates in the form of lipid droplets in the cytoplasm. The extent of lipid droplet formation in each cell can be assessed in the absence of any staining by 90 degrees light scatter intensity, one of the basic parameters of flow cytometry.

Cell Line, Transformed