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Biomedical subjects

J Chihara

Publications and source records attributed to J Chihara.

At least 73 records · Page 4Linked to original sources
PubMed1997

Expression of mRNA for RANTES in human eosinophils.

RANTES has been considered to play an important role in various immune and allergic disorders since RANTES is a potent chemoattractant for various important inflammatory cells such as eosinophils. Eosinophils, on the other hand, are considered to be the major inflammatory cells in bronchial asthma since eosinophil-specific granule proteins can damage bronchial mucosal cells. The recent demonstration that eosinophils themselves could synthesize some cytokines such as IL-5 indicates the role of these cytokines not only in paracrine but also in autocrine regulation of eosinophil production, differentiation and activation. Therefore, in this study, we examined mRNA for RANTES and release of RANTES by human eosinophils. The present findings revealed that eosinophils obtained from asthmatic patients could express and release RANTES. Taken together, these findings suggest that eosinophils play a crucial role in the pathogenesis, particularly in eosinophil and T lymphocyte recruitment into the inflamed sites in asthma through RANTES production.

Asthma↗
PubMed1997

Steroid-induced changes of eosinophils in atopic dermatitis.

We investigated whether apoptosis of eosinophils is specific to atopic dermatitis (AD), or also occurs in other diseases with eosinophilia. We examined the survival of eosinophils cultured with corticosteroids: (1) Clinically, steroid administration significantly decreased high peripheral blood eosinophil cell counts in patients with AD. (2) Treatment with recombinant human (rh) IL-5 prolonged the life span of eosinophils derived from patients with AD and of those derived from non-AD patients with eosinophilia. However, there were differences in the survival rates in the presence of rhIL-5: the eosinophils from non-AD patients showed 1.4-fold higher survival rates than those from AD patients at 24 h. In the presence of steroids, the eosinophils from non-AD patients showed a survival rate double that of those from AD patients at 24 h. (3) In eosinophils from patients with AD, the survival rate decreased significantly in a time- and steroid-concentration-dependent manner. Steroid administration significantly inhibited the survival rate of eosinophils from patients with AD compared to those of monocytes and neutrophils. These findings suggest that apoptosis induced by steroids decreases the eosinophil count in vivo in patients with AD. There may be a difference in the incidence of steroid-induced apoptosis between eosinophil cells from patients with AD and those from patients with eosinophilia due to other underlying diseases.

Apoptosis↗
PubMed1997

[The roles of adhesion molecules, cytokines and chemokines in allergic inflammation].

Recently, adhesion molecules, as well as eosinophils, have been found to play an important role in the inflammatory processes in allergic disease. We demonstrated here as below. Characteristics of adhesion molecules expression on eosinophils in asthma, namely, high-intensity expression of adhesion molecules. Induction of adhesion molecule expression by PAF and RANTES and in addition induction by the supernatant of mononuclear cells from mite-allergic asthmatic patients stimulated with mite-allergen as well as with a combination of the recombinant IL-3, GM-CSF and IL-5. Elevated soluble ICAM-1 in bronchial asthma. Moreover, the presence of a large variety of membrane receptors and the identification of cytotoxic molecules (mainly granule basic proteins) have indicated that eosinophils should be considered as effector cells. We therefore investigated the possible release of granule proteins in response to signaling from ICAM-1 and its ligands. The concentrations of eosinophil cationic protein and eosinophil-derived neurotoxin in supernatants of eosinophils were significantly greater (p < 0.05) in the presence of recombinant soluble ICAM-1 than without it. These results suggest that signaling from ICAM-1 and its ligands might induce eosinophil activation and might be involved in degranulation of eosinophil granule proteins. In addition, reactive oxygen species generated by eosinophils have also been considered capable of causing airway injury at the inflamed focus. We examined the effect of recombinant soluble ICAM-1 and its ligands on eosinophil-induced radical oxygen products. Recombinant soluble ICAM-1 augmented eosinophil oxidative metabolism. It was concluded that signaling via adhesion molecules might play an important role in the pathogenesis of allergic inflammation through activation of eosinophils, such as through an increase in oxidative metabolism or degranulation of eosinophil granule proteins.

Animals↗
PubMed1997

[Molecular epidemiological analysis of Pseudomonas aeruginosa by pulsed-field gel electrophoresis].

In order to see the nosocomial infection by Pseudomonas aeruginosa (P. aeruginosa) in the Akita University Hospital, we analyzed the serotype and genotype for 150 strains isolated from various clinical specimens from 1994 to 1996. One hundred strains chosen at random were divided into 11 serotypes by serotyping and into 50 genotypes by pulsed-field gel electrophoresis of Spe I-digested P. aeruginosa genomic DNAs. Serotype E strains, most common, gave 17 genome patterns. Fifty strains separated periodically in certain wards had further 7 genome patterns. The strains isolated from one patient with different times or with different serotypes showed the same stable genotype. Genome patterns were inconsistent with susceptibility to antimicrobial agents. Both drug-susceptible and -resistant strains were found in strains with the same genome pattern. The genome pattern was identical, even though the susceptibility was different due to isolation time or storage. This suggested that the multidrug-resistant strains of P. aeruginosa expanded in the hospital were not derived from one original strain.

Cross Infection↗
PubMed1996

Elevated levels of soluble ICAM-1 in serum of patients with acute myeloid leukemia undergoing bone marrow transplantation.

Serum soluble ICAM-1 concentrations were measured in 10 patients with or without chronic graft-vs.-host disease (GVHD) after allogeneic bone marrow transplantation. The serum soluble ICAM-1 levels in the patients with chronic GVHD were significantly higher than that in the patients without chronic GVHD. The data indicated that serum soluble ICAM-1 is a useful parameter for predicting chronic GVHD.

Acute Disease↗
PubMed1996

Elevated local production of neopterin from alveolar macrophages in patients with internal lung diseases.

1. We measured the neopterin level in the supernatant of cultured alveolar macrophages from patients with interstitial lung diseases (ILD patients) as a marker for the activation of alveolar macrophage. 2. In ILD patients, the supernatant neopterin level (40.1 +/- 7.8 pmol/ml) was significantly higher (P < 0.01) than that in control subjects (10.0 +/- 1.6 pmol/ml). 3. We also found that macrophage-colony stimulating factor (M-CSF) and interleukin-2 (IL-2) augmented neopterin production from alveolar macrophage in both ILD patients (51.6 +/- 10.4 and 60.1 +/- 10.8 pmol/ml, respectively, P < 0.01) and control subjects (28.1 +/- 6.0 and 25.7 +/- 4.9 pmol/ml, respectively). 4. These findings suggest that alveolar macrophages produce neopterin by M-CSF or IL-2.

Adult↗
PubMed1996

RANTES mRNA expression in skin and colon of patients with atopic dermatitis.

The expression of RANTES mRNA in dermal and colonic tissue was examined in patients with atopic dermatitis by the reverse transcription polymerase chain reaction method. RANTES mRNA was detected in the colon in 8 of 10 patients and in 1 of 5 control patients. It was present in rashes in 9 of 10 patients and at non-eruptive sites in 5 of 7 patients. These findings suggest that RANTES is involved in eosinophil infiltration and T cell infiltration in atopic dermatitis.

Adolescent↗
PubMed1996

Eosinophil cationic protein induces insulin-like growth factor I receptor expression on bronchial epithelial cells.

Although the biologic activity of eosinophil-specific granule proteins, e.g. eosinophil cationic protein (ECP) has been attributed to cytotoxic properties, it has also been shown to be attributable to non-cytotoxic activation of various inflammatory cells. In addition, airway epithelial cells have been reported to express insulin-like growth factor I (IGF-I) receptor and proliferate in response to IGF-I. The present study examined the regulation of expression of IGF-I receptor on bronchial epithelial cells by eosinophil granule proteins was examined. ECP significantly induced IGF-I receptor expression on bronchial epithelial cells compared with unstimulated cells. These findings suggest that eosinophils participate in the repair process of injured bronchial epithelial cells in the inflamed focus through augmentation of IGF-I receptor expression by suboptimal degranulation of eosinophil granule proteins, e.g. ECP.

Blood Proteins↗
PubMed1996

Expression of CD23, CD32, Mac-1 and other adhesion molecules in eosinophils in strongyloidiasis and HTLV-I-positive patients.

The relationship between human T-lymphotropic virus I (HTLV-I) infection and strongyloidiasis has recently become an important problem. This study compared the expression of CD23, CD32, Mac-1 and other adhesion molecules in eosinophils of patients with strongyloidiasis positive for anti-(HTLV-I) antibodies and in those negative for the antibodies. The expression of CD23, Mac-1 and intercellular adhesion molecule-1 (ICAM-1) on eosinophils of patients with strongyloidiasis was augmented in comparison with normal subjects and HTLV-I carriers. There were no significant differences, however, in the expression of CD23, CD32, Mac-1 and adhesion molecules (ICAM-1, leukocyte function-associated antigen-1 alpha (LFA-1 alpha), LFA-1 beta, very late antigen-4) on eosinophils of patients with strongyloidiasis positive for anti-HTLV-I antibodies in comparison with those negative for these antibodies.

Adult↗
PubMed1996

Regulation of eosinophil cell death by adhesion to fibronectin.

Fibronectin is an extracellular matrix (ECM) that binds to very late antigen-4 (a beta 1 integrin molecule) expressed by eosinophils. To investigate the effect of adherence to fibronectin on regulation of eosinophil cell death, survival of eosinophils was examined by trypan blue exclusion and Fas antigen expression on the cell surface using an eosinophilic cell line (EoL-1). Adhesion to fibronectin resulted in prolongation of eosinophil survival (fibronectin vs. bovine serum albumin (BSA), 62.9 +/- 5.10 vs. 53.9 +/- 4.30% viability at 72 h) and the decreasement of Fas antigen expression on EoL-1 (fibronectin vs. BSA, 24.3 +/- 2.15 vs. 74.5 +/- 8.25% positive). These findings suggest that eosinophil adhesion to ECM via adhesion molecules plays an important role in the pathogenesis of allergic inflammation, which involves eosinophil accumulation at the inflammatory site, through regulation of eosinophil cell death.

Apoptosis↗
PubMed1996

Corticosteroid-induced apoptosis of eosinophils in atopic dermatitis patients.

We examined the mechanism by which steroid administration significantly decreases the high eosinophil cell count in peripheral blood in patients with atopic dermatitis (AD). Eosinophils were isolated from the peripheral blood of patients with moderate or severe adult AD, and cultured. After steroid was added to the culture medium, we examined the changes in eosinophils, i.e., 1) the survival rates, 2) morphological changes and 3) fragmentation of DNA with respect to 2 factors, the steroid concentration and culture time. The steroid or interleukin-5 (IL-5) were added to eosinophils from patients with AD and those from non-AD patients with eosinophilia to compare serial changes in the survival rate. In eosinophils from patients with AD, the survival rate significantly decreased time-dependently and steroid concentration-dependently. Steroid administration significantly inhibited the survival rate of eosinophils from patients with AD compared to the survival rates of monocytes and neutrophils. The nuclei of eosinophils were serially reduced, and disappeared 72 hours after steroid administration. Simultaneously, cell size decreased, although the cell membrane remained intact. Granules developed in the cell membrane. In the steroid-treated group, apoptotic cells appeared earlier than in the untreated group. The number of cells showing apoptosis was increased steroid concentration-dependently. The number of DNA ladders was increased time-dependently and steroid concentration-dependently. In eosinophils derived from patients with AD and those derived from non-AD patients with eosinophilia, treatment with recombinant human (rh) IL-5 prolonged the life-span of cells. However, there were differences in the survival rates. In the presence of rhIL-5, the eosinophils from non-AD patients survived 1.4 times longer than those from AD patients at 24 hours (P < 0.05). In the presence of steroid, the eosinophils from non-AD patients survived twice as long as those from AD patients at 24 hours (P < 0.01). These findings suggest that apoptosis induced by steroids decreases the eosinophil count in vivo in patients with AD. There may be a difference in the incidence of steroid-induced apoptosis between eosinophil cells from patients with AD and those from patients with eosinophilia due to other underlying diseases.

Adolescent↗
PubMed1996

Elevated plasma RANTES levels in patients with atopic dermatitis.

Eosinophils and T cells are involved in the pathologic process of atopic dermatitis. To further understand the role of these cells, and the possible involvement of RANTES, in the pathogenesis of atopic dermatitis, we measured the plasma level of RANTES using the sandwich ELISA. The mean plasma level of RANTES in 11 patients with atopic dermatitis was significantly higher than that of 15 normal control subjects. RANTES levels were higher in patients with severe form of atopic dermatitis than that of patients with mild disease. These findings suggest that RANTES may play a role in the recruitment and activation of eosinophils and T cells in atopic dermatitis.

Adolescent↗
PubMed1996

[Allergic granulomatous angitis with hyper expression of eosinophilic adhesion molecules].

A 43-year-old man who had been treated for bronchial asthma presented with an increase in dry coughing and wheezing for one and a half years. In August 1994, the patient noted progressive dyspnea on exertion. A chest radiograph revealed nodular opacity in the right upper lung field. In November 1994, the patient was admitted to Kinki University Hospital with an erythematous rash on the soles of both feet. Examination of a specimen biopsy of the skin lesion revealed granuloma with eosinophil infiltration. Peripheral blood eosinohilia was noted and a bone marrow examination also revealed an increased level of eosinophils. Another chest radiograph revedaled that the nodular opacity had disappeared and a new bilateral pleural effusion was seen. Eosinophils were the predominant cells in the pleural effusion. the patient's condition was further complicated by myocarditis. Allergic granulomatous angitis (Churg-Strauss syndrome) was diagnosed and steroid therapy was started. After the start of steroid therapy, the skin eruption disappered and the myocarditis became less severe. Symptoms of asthma were also well controlled. The eosinophils had hypersegmented unclei and increased expression of adhesion molecules on their surfaces.

Adult↗
PubMed1996

[Prologue--adhesion molecules].

The studies on the roles of adhesion molecules in the various diseases recently have been greatly extended. Here, excellent studies on adhesion molecules from several laboratories are demonstrated in this symposium in order to clarify the important roles of adhesion molecules in the various diseases and disorders and develop the new laboratory examination on adhesion molecules in the future laboratory medicine.

Cell Adhesion Molecules↗
PubMed1996

[The roles of adhesion molecules, cytokines and chemokines in relation to eosinophil activation in allergic inflammation].

Several characteristics of human eosinophil heterogeneity, as well as the existence of eosinophil subpopulations, "normodense" and "hypodense", have been reported in diseases associated with hypereosinophilia. Hypodense eosinophils can be distinguished by the increased expression of various membrane receptors including IL-5 receptor (J Exp Med 172:1347) and various protein expression (J Immunol 142:4416). Recently, adhesion molecules, as well as eosinophils, have been found to play an important role in the inflammatory processes in allergic disease. We demonstrated here as below: 1) Characteristics of adhesion molecules expression on eosinophils in asthma, namely, high-intensity expression of adhesion molecules. 2) Induction of adhesion molecule expression by PAF and RANTES and in addition induction by the supernatant of mononuclear cells from mite-allergic asthmatic patients stimulated with mite-allergen as well as with a combination of the recombinant IL-3, GM-CSF, and IL-5 (Immunol Lett 42:25, 1994 & 46:241, 1995). 3) Elevated soluble ICAM-1 in bronchial asthma (Lancet 343:1108, 1994).

Asthma↗