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Biomedical subjects

J Chihara

Publications and source records attributed to J Chihara.

At least 91 records · Page 5Linked to original sources
PubMed1996

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

Patients with hypereosinophila have at least two subpopulation of eosinophils: "normodense" and "hypodense". Hypodense eosinophils can be distinguished by their increased expression of various membrane receptors including IL-5 receptors (J Exp Med 172: 1347) and by the expression of particular proteins (J Immunol 142: 4416). Recently, adhesion molecules have also been found to play an important role in the inflammatory processes in allergic disease. 1) Adhesion molecules were found to be strongly expressed on eosinophils from patients with asthma. 2) Platelet activating factor and induced the expression of adhesion molecules as did the supernatant of mononuclear cells from mite-allergic patients with asthma stimulated either with mite allergen or with a combination of recombinant IL-3, GM-CSF, and IL-5 (Immunol, Lett. 42: 25, '94, & 46: 241, '95). 3) Patients with bronchial asthma had a high level of soluble ICAM-1) (Lancet. 343: 1108, '94). Moreover, the presence of a large variety of membrane receptors and the identification of cytotoxic molecules (mainly granule basic proteins) indicate that eosinophils should be considered effector cells. Therefore the release of granule proteins in response to ICAM-1 and its ligands was studied. The concentrations of eosinophil cationic protein and eosinophil-derived neurotoxin in supernatants of eosinophils were significantly greater in the presence of recombinant soluble ICAM-1 than in its absence (p < 0.05). These results suggest that signals from ICAM-1 and its ligands induce eosinophil activation and are 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 sites of inflammation. The effect of recombinant soluble ICAM-1 and its ligands on eosinophil-induced radical oxygen products was studied. Recombinant soluble ICAM-1 augmented eosinophil oxidative metabolism. Therefore, signaling via adhesion molecules might play an important role in the pathogenesis of allergic inflammation. Specifically, it may activate eosinophils and increase oxidative metabolism or cause degranulation of eosinophil granule proteins.

Cell Degranulation↗
PubMed1995

Possible involvement of mononuclear cells stimulated with specific allergen from asthmatic patients in ICAM-1 expression on the eosinophilic cell line.

Adhesion molecules, particularly intercellular adhesion molecule-1 (ICAM-1), recently have been considered to play a key role in inflammatory processes in asthma. Thus, from the point of view of cell interactions between mononuclear cells and eosinophils, we examined whether the supernatant of mononuclear cells (MNC) obtained from mite-allergic asthmatic patients cultured with specific allergen is involved in ICAM-1 expression using an eosinophilic cell line (EoL). ICAM-1 expression was induced by the supernatant of MNC from mite-allergic asthmatic patients stimulated with mite allergen as well as by a combination of IL-3, GM-CSF, and IL-5. Thus, we could conclude that some cytokines produced by specific allergen-stimulated MNC in asthmatics might be involved in allergic inflammation through the induction of adhesion molecule expression such as ICAM-1 on eosinophils in asthma or allergic disorders.

Allergens↗
PubMed1995

A comparative study of eosinophil isolation by different procedures of CD16-negative depletion.

Eosinophils were isolated by the three methods of CD16-negative depletion: 1) magnetic beads, 2) fluorescence-activated cell sorter (FACS), and 3) complement reaction. Their purity, yield, and viability were compared. The second procedure produced well purity and viability (94.65 +/- 1.51% and 94.98 +/- 1.40%, respectively) but low yield of eosinophils (65.47 +/- 2.47%). The viability of cells obtained by the third procedure was not efficient (80.83 +/- 2.85%), while the purity and the yield were efficient (96.23 +/- 1.09% and 90.75 +/- 1.72%, respectively). In conclusion, the magnetic beads method (purity: 98.02 +/- 0.45%, yield: 91.05 +/- 2.43%, viability: 97.57 +/- 0.37%) was the most advantageous of these three procedures. Moreover, in the functional assay, radical oxygen products from eosinophils isolated by the procedure with complement reaction were less than with the magnetic beads or FACS procedures.

Cell Separation↗
PubMed1995

Effect of RANTES on eosinophil adhesion to plates coated with recombinant soluble intercellular adhesion molecule-1 and expression of beta 2-integrin adhesion molecules on eosinophils.

RANTES, a member of the 8-kDa cytokine family, has been shown to possess chemotactic activity for eosinophils. In this study, RANTES augmented isolated human eosinophil adhesion to plates coated with recombinant soluble intercellular adhesion molecule 1. In addition, RANTES did not augment the expression of beta 2-integrin adhesion molecules (lymphocyte function associated antigen-1 alpha (LFA-1 alpha), LFA-1 beta, complement receptor type 3 (CR3)) on human eosinophils. These findings suggest that RANTES not only modulates the chemotactic activity of eosinophils but also intensifies the function of eosinophil adhesion without augmenting the expression of beta 2-integrin adhesion molecules.

Asthma↗
PubMed1995

Effect of RANTES on intracellular expression of EG2 antigen in eosinophils.

RANTES, which is released from thrombin-stimulated platelets, is a member of the 8-kDa cytokine family that has been shown to possess chemotactic activity for eosinophils. The effect of RANTES on the intracellular expression of EG2 antigen in eosinophils was examined in this study. RANTES augmented the intracellular expression of EG2 antigen in eosinophils. These findings suggest that RANTES not only modulates the chemotactic activity of eosinophils but also intensifies the function of eosinophil activation.

Asthma↗
PubMed1995

Increased eosinophil oxidative metabolism by treatment with soluble intercellular adhesion molecule-1.

Adhesion molecules may play an important role not only in adherence of inflammatory cells (particularly eosinophils) to an inflamed focus but also in activation of these cells. It is therefore of interest to evaluate eosinophil activation via intercellular adhesion molecule-1 (ICAM-1) and the beta 2-integrin family, namely CR3 (Mac-1), lymphocyte function-associated antigen (LFA)-1 alpha and LFA-1 beta, which are ligands for ICAM-1. Reactive oxygen species generated by eosinophils have also been considered capable of causing airway injury at the inflamed focus. This study examined the effect of recombinant soluble ICAM-1 and its ligands on eosinophil-induced radical oxygen products in terms of luminol-dependent chemiluminescence. 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, e.g. an increase in oxidative metabolism.

Asthma↗
PubMed1995

Adhesion to fibronectin augments eosinophil radical oxygen products.

Fibronectin, an extracellular matrix component, is a ligand for very late activation antigen (VLA)-4, which is one of the beta 1-integrin family of molecules expressed by eosinophils. This study examined the effect of adherence to fibronectin on radical oxygen products from eosinophils. Adhesion of eosinophils to fibronectin resulted in enhancement of eosinophil production of radical oxygen species, as determined by luminol-dependent chemiluminescence of eosinophils stimulated with calcium ionophore. It was concluded that eosinophil adhesion to extracellular matrix via adhesion molecules may be important in the pathogenesis of allergic inflammation through eosinophil activation.

Asthma↗
PubMed1995

Possible release of eosinophil granule proteins in response to signaling from intercellular adhesion molecule-1 and its ligands.

The presence of a large variety of membrane receptors and the identification of cytotoxic molecules (mainly granule basic proteins) have indicated that eosinophils should br considered as effector cells. It has recently been suggested that adhesion molecules, particularly intercellular adhesion molecule-1 (ICAM-1), play an important role in allergic inflammation, for example in bronchial asthma. This study therefore investigated the possible release of granule protein 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, e.g. eosinophil cationic protein and eosinophil-derived neurotoxin.

Asthma↗
PubMed1995

[Effect of rantes (regulated on activation, normal T expressed and secreted) on eosinophil adhesion to plasma coated glass using eosinophilic cell line (EoL-1)].

Recently, adhesion molecules expressed on various inflammatory cells, especially on eosinophils are considered to play an important role in allergic inflammation such as bronchial asthma. RANTES (Regulated on activation normal T expressed and secreted) seems to be the most important chemokine which belongs to Platelet factor 4 (PF4) superfamily, since RANTES is revealed as a chemotactic factor for eosinophils as well as memory T cells or monocytes. In this study, we examined the effect of RANTES on eosinophil adhesion to plasma coated glass using eosinophilic cell line named EoL-1. RANTES augmented EoL-1 adherence to Plasma coated glass and EoL-1 adherence to plasma coated glass was inhibited by anti-VLA-4 antibody, anti-CR3 antibody. On the other hand, RANTES did not augment expression of adhesion molecules (VLA-4, CR3) on EoL-1. These findings indicate that RANTES intensify the adhesion of eosinophils without augmentation of their expression, and suggest that it induce qualitative, but not quantitative changes in their adherence. Taken together, our study suggest that RANTES up-regulates the inflammatory reaction through augmentative effect on adhesion of eosinophils in bronchial asthma.

Cell Adhesion↗
PubMed1995

[A case of acute eosinophilic pneumonia: bronchoalveolar lavage findings before and after steroid treatment].

An 18-year-old woman presented with coughing, fever, progressive dyspnea, and diffuse infiltrates on the chest X-ray film. Analysis of bronchoalveolar lavage fluid showed 73% eosinophils. Acute eosinophilic pneumonia was diagnosed. Methylprenisolone, 1 g per day was given for three days and her condition improved dramatically. No relapse was observed. Analysis of bronchoalveolar lavage fluid also showed lymphocytosis, abnormally high concentrations of ECP, GM-CSF, IL-5 and sICAM-1, and hypersegmentation of eosinophil nuclei. After steroid treatment almost all these findings returned to normal; only lymphocytosis remained. Precipitating antibodies against four kinds of fungi, including Trichoderma viridae, were noted in the serum, but the environmental provocation test was negative and those fungi were not detected in the environmental culture growth. Comparison of bronchoalveolar lavage findings obtained before and after steroid treatment can provide information on the mechanism of eosinophil accumulation in the lung. This case also draws attention to the relationship between acute and chronic eosinophilic pneumonia.

Acute Disease↗
PubMed1995

[Adhesion to fibronectin regulates expression of adhesion molecules on eosinophils].

To elucidate the mechanism for the accumulation of eosinophils through adherence in allergic inflammation, we investigate whether adhesion of eosinophils to extracellular matrix (ECM) regulates the expression of adhesion molecules on eosinophils. Highly purified eosinophils obtained from asthmatic patients were cultured on BSA or fibronectin (FN) coated plates for 4 or 48 hours. After then, removed cells were examined about the expression of each adhesion molecule. Cultured on FN resulted in the increment of the expressive CR 3 (CD11b) (BSA vs FN; MFI ratio 10.50 vs 12.09 p < 0.05), and decrement of the expressive VLA-4 (CD49d) on the eosinophils (3.93 vs 2.91 (4 h) p < 0.05, 2.86 vs 2.09 (48 h) p < 0.05). Thus, we could conclude that eosinophils adhesion to ECM via adhesion molecules might play an important role in the pathogenesis of allergic inflammation through the involvement in the regulation of the expression of adhesion molecules on eosinophils.

Cell Adhesion↗
PubMed1995

[Effect of cytokine RANTES on induction of activated eosinophils].

The cytokine RANTES (regulated on activation, normal T expressed and secreted) is a member of the platelet factor 4 superfamily and is a chemoattractant for eosinophils. To study the effect of RANTES on induction of activated eosinophils, flow cytometry was used to measure the expression of intracellular EG2 in eosinophils. The concentration of eosinophil cationic protein in the culture supernatant of eosinophils stimulated with RANTES was also measured. Expression of EG2 and the mean fluorescence intensity ratio were greater in eosinophils stimulated with RANTES than in control eosinophils. Eosinophils stimulated with RANTES also produced more eosinophil cationic protein than did control eosinophils.

Blood Proteins↗
PubMed1995

Possible low response of C-reactive protein production in eosinophilic pneumonia.

C-reactive protein (CRP) in the patients with eosinophilic pneumonia was examined compared with that of bacterial pneumonia. While no difference between erythrocyte sedimentation rate (ESR) in eosinophilic pneumonia (mean +/- SE: 74.5 +/- 10.6 mm/hr) and that in bacterial pneumonia (86.2 + 7.7 mm/hr) was observed, serum CRP level (3.87 +/- 1.24 mg/dL) and alpha 2-macroglobulin level (182.53 +/- 13.00 mg/dL) in eosinophilic pneumonia were lower in comparison with those in bacterial pneumonia (14.89 +/- 1.34 mg/dL, 315.65 +/- 11.54 mg/dL, respectively), suggesting that the pathogenesis of eosinophilic pneumonia might involve defective secretion of certain cytokine related to the production of acute-phase reactant proteins such as interleukin-6.

Blood Sedimentation↗
PubMed1994

Induction of beta 2 integrin expression on an eosinophilic cell line (EoL-1) by the supernatant of mononuclear cells stimulated with specific allergen from asthmatic patients.

Adhesion molecules recently have been considered to play an important role in inflammatory processes in bronchial asthma. Our previous study revealed high expression of beta 2-integrin family (CR3, LFA-1 alpha, CD18) on hypodense eosinophils. Thus, from the point of view of cell-to-cell interaction between mononuclear cells and eosinophils, we examined whether the supernatant of mononuclear cells obtained from mite-allergic asthmatic patients cultured with specific allergen mite-allergen is involved in adhesion molecule expression using an eosinophilic cell line (EoL-1). These characteristics of beta 2-integrin family expression (high expression of beta 2 integrin) were induced by the supernatant of mononuclear cells from mite-allergic asthmatic patients stimulated with mite-allergen as well as with a combination of the recombinant eosinophilopoietic growth cytokines (IL-3, GM-CSF and IL-5). Thus, we could conclude that some cytokines produced by specific allergen stimulated mononuclear cells in asthmatics might be involved in allergic inflammation through the induction of adhesion molecule expression on eosinophils in asthma or allergic disorders.

Allergens↗