Biomedical subjects

M Hirashima

Publications and source records attributed to M Hirashima.

At least 37 records · Page 2Linked to original sources

PubMed1999

Ecalectin as a T cell-derived eosinophil chemoattractant.

In our previous papers, we have shown that human T cells produce a unique eosinophil chemotactic factor (ECF), termed Ecalectin, with a molecular weight of about 30-50 kD during interaction with BALL-1 (a B cell line) extracts, antigen or mitogen. A 1.6-kB cDNA was isolated from a human T cell-derived expression library that encodes Ecalectin. Ecalectin is a 36-kD protein consisting of 323 amino acids based on its deduced amino acid sequence. Ecalectin was found to be a variant of human galectin-9, a member of the growing family of animal lectins exhibiting affinity for beta-galactosides. Recombinant Ecalectin, expressed in COS cells, exhibited potent ECF activity in vitro and in vivo in a dose-dependent manner but not chemotactic activity for neutrophils, lymphocytes, or monocytes. The finding that the Ecalectin transcript is present in various lymphatic tissues and that its expression increases substantially in antigen-activated peripheral blood mononuclear cells suggests that Ecalectin is an important T cell-derived regulator of eosinophil recruitment in allergic reaction sites.

Animals↗

PubMed1999

Difference in apoptotic function between eosinophils from peripheral blood and bronchoalveolar lavage in chronic eosinophilic pneumonia.

We compared apoptosis in eosinophils from bronchoalveolar lavage (BAL-Eos) with that in eosinophils from peripheral blood (PB-Eos) of 4 patients with chronic eosinophilic pneumonia (CEP). The survival rate of the BAL-Eos on the 3rd day of the culture was significantly higher than that of the PB-Eos (39.1 vs. 1.3%). The percentage of apoptotic cells in the PB-Eos after a 24-hour incubation was higher than that in the BAL-Eos (21.7 vs. 10.6%) according to an analysis with annexin V. We further found that ECF-PI9, an eosinophil chemotactic factor (ECF) derived from an established T cell line (STO-2), significantly suppressed the apoptosis of both PB-Eos and BAL-Eos and prolonged their survival. The expression of Fas on PB-Eos was significantly suppressed by ECF-PI9 (18.5 to 7.37%, p < 0. 05), whereas ECF-PI9 failed to suppress the Fas expression on BAL-Eos (3.3 to 3.6%). In addition, an ECF with similar physicochemical properties and biological functions was isolated from the BAL fluid of patients with CEP. These data demonstrate differences between PB-Eos and BAL-Eos, and indicate that ECF-PI9 is involved in the pathogenesis of CEP.

Apoptosis↗

PubMed1998

Human ecalectin, a variant of human galectin-9, is a novel eosinophil chemoattractant produced by T lymphocytes.

A 1.6-kilobase pair cDNA was isolated from a human T-cell-derived expression library that encodes a novel eosinophil chemoattractant (designated ecalectin) expressed during allergic and parasitic responses. Based on its deduced amino acid sequence, ecalectin is a 36-kDa protein consisting of 323 amino acids. Although ecalectin lacks a hydrophobic signal peptide, it is secreted from mammalian cells. Ecalectin is not related to any known cytokine or chemokine but rather is a variant of human galectin-9, a member of the large family of animal lectins that have affinity for beta-galactosides. Recombinant ecalectin, expressed in COS cells and insect cells, exhibited potent eosinophil chemoattractant activity and attracted eosinophils in vitro and in vivo in a dose-dependent manner but not neutrophils, lymphocytes, or monocytes. The finding that the ecalectin transcript is present in abundance in various lymphatic tissues and that its expression increases substantially in antigen-activated peripheral blood mononuclear cells suggests that ecalectin is an important T-cell-derived regulator of eosinophil recruitment in tissues during inflammatory reactions. We believe that this is the first report of the expression of an immunoregulatory galectin expressed by a T-cell line that is selective for eosinophils.

Amino Acid Sequence↗

PubMed1998

The ratio of neutrophils to lymphocytes and the phenotypes of neutrophils in patients with early gastric cancer.

We examined 55 patients (40 male, 15 female) who were diagnosed from 1987 to 1991 as having early gastric cancer (EGC) stage I according to the general rules of classification of the Japanese Research Society for Gastric Cancer. Of the 55 patients, 42 (30 male, 12 female) were alive in April 1992. The prognosis correlated well with the ratio of neutrophils to lymphocytes (N/L ratio) but not with the total number of white blood cells in the peripheral blood. The patients were divided into two groups according to their N/L ratio. Of the 29 patients with an N/L ratio less than 2, 27 were alive in 1992, whereas only 15 of the 26 patients with an N/L ratio of 2 or more were alive (chi2 analysis, P=0.0022). We further examined the phenotypes of neutrophils from 29 other patients with EGC at the time of diagnosis before surgical operation. These patients were divided into two groups: 17 patients with a low N/L ratio (less than 2) and 12 patients with a high N/L ratio (2 or more). CD10 and CD35 expressions on neutrophils from the patients with a low N/L ratio were lower than those from the patients with a high N/L ratio. The N/L ratio correlated well with both CD10 and CD35 expression, whereas no correlation was observed between the numbers of neutrophils and the expression of these phenotypes. The respiratory burst of neutrophils from the patients with a high N/L ratio was higher than that of neutrophils from the patients with a low N/L ratio, though there was no correlation in the phagocytic activity between both groups. It was thus suggested that the heterogeneity of neutrophils is, at least partly, related to the prognosis of patients with EGC.

Adult↗

PubMed1998

Enhancement of anti-tumor activity of natural killer cells by BALL-1, a B cell lymphoma line.

The anti-tumor activity of human peripheral blood mononuclear cells (PBMC) against various tumor cell line cells (K562, Daudi, KMG-2, and KATOIII) was enhanced by coculture with irradiated BALL-1, but not with other irradiated B cell line cells (NALM-1, Namalwa, and Daudi). PBMC cocultured with BALL-1, however, failed to exhibit evident cytotoxicity against autologous concanavalin A-induced lymphoblasts. The enhancement of the anti-tumor activity seemed not to be correlated with EBNA and HLA-DR expression on B cell line cells. Monoclonal antibodies (mAbs) against interleukin (IL)-2, interferon-gamma, IL-12, IL-15, tumor necrosis factor-alpha and lymphotoxin showed little or no suppression of the anti-tumor activity of PBMC treated with irradiated BALL-1. Furthermore, the culture supernatants of BALL-1 failed to enhance the anti-tumor activity of PBMC, suggesting no involvement of soluble factors in the induction of the anti-tumor activity. The anti-tumor activity of PBMC treated with BALL-1 was synergistically enhanced by an additional IL-2 stimulation. Periodate-lysine-paraformaldehyde-fixed, but not ethanol- or acetone-fixed, BALL-1 could significantly enhance the anti-tumor activity. Furthermore, BALL-1-derived membrane fraction, but not that of Daudi, enhances the anti-tumor activity. It was thus suggested that some membrane glycoproteins on the cell surface of BALL-1 play a crucial role in the induction of the anti-tumor activity. By analysis using mAbs against human leukocytes, we found that depletion of CD11b, CD16, and CD56-positive cells resulted in decreased anti-tumor activity, suggesting that the main effector cells in the BALL-1-induced anti-tumor activity were natural killer (NK) cells. The present results thus raise the possibility that BALL-1, probably via membrane glycoproteins, modulates NK cell-mediated anti-tumor activity.

Antibodies, Monoclonal↗

PubMed1998

Progressive lineage analysis by cell sorting and culture identifies FLK1+VE-cadherin+ cells at a diverging point of endothelial and hemopoietic lineages.

Totipotent murine ES cells have an enormous potential for the study of cell specification. Here we demonstrate that ES cells can differentiate to hemopoietic cells through the proximal lateral mesoderm, merely upon culturing in type IV collagen-coated dishes. Separation of the Flk1+ mesoderm from other cell lineages was critical for hemopoietic cell differentiation, whereas formation of the embryoid body was not. Since the two-dimensionally spreading cells can be monitored easily in real time, this culture system will greatly facilitate the study of the mechanisms involved in the cell specification to mesoderm, endothelial, and hemopoietic cells. In the culture of ES cells, however, lineages and stages of differentiating cells can only be defined by their own characteristics. We showed that a combination of monoclonal antibodies against E-cadherin, Flk1/KDR, PDGF receptor(alpha), VE-cadherin, CD45 and Ter119 was sufficient to define most intermediate stages during differentiation of ES cells to blood cells. Using this culture system and surface markers, we determined the following order for blood cell differentiation: ES cell (E-cadherin+Flk1-PDGFRalpha-), proximal lateral mesoderm (E-cadherin-Flk1+VE-cadherin-), progenitor with hemoangiogenic potential (Flk1+VE-cadherin+CD45-), hemopoietic progenitor (CD45+c-Kit+) and mature blood cells (c-Kit-CD45+ or Ter119+), though direct differentiation of blood cells from the Flk1+VE-cadherin- stage cannot be ruled out. Not only the VE-cadherin+CD45- population generated from ES cells but also those directly sorted from the yolk sac of 9.5 dpc embryos have a potential to give rise to hemopoietic cells. Progenitors with hemoangiogenic potential were identified in both the Flk1+VE-cadherin- and Flk1+VE-cadherin+ populations by the single cell deposition experiment. This line of evidence implicates Flk1+VE-cadherin+ cells as a diverging point of hemopoietic and endothelial cell lineages.

Animals↗

PubMed1997

Induction of eosinophil chemotactic factor production from human peripheral blood mononuclear cells by solubilized BALL-1, a B cell lymphoma line.

We have previously shown that irradiated BALL-1, a B lymphoma line, stimulates OKT4 T cells to produce a unique eosinophil chemotactic factor (ECF) which suppresses the respiratory burst of eosinophils. In the present experiments, we found that solubilized BALL-1 also stimulated peripheral blood mononuclear cells (PBMC) to produce ECF activity in a dose-dependent manner. PBMC treated with solubilized BALL-1 produced ECF within 24 h. ECF production-inducing factor (ECF-IF) had affinity with lentil lectin beads, suggesting that ECF-IF has glucose or mannose as carbohydrate moieties. Furthermore, we found that ECF-IF activity was comprised of at least four ECF-IF with different isoelectric points (pI): ECF-IF1 had a pI of 4-5, ECF-IF2 a pI of about 6, ECF-IF3 a pI of about 7, and ECF-IF4 a pI of about 8. ECF-IF1 stimulated PBMC to produce mainly an ECF with a pI of about 7-8, whereas the rest of ECF-IF induced an ECF with a different pI. The present results suggest that the membrane glycoproteins of some tumors, at least, partly contribute to tissue eosinophilia in the stroma of the malignant tumor by inducing ECF production from PBMC.

Chemotactic Factors, Eosinophil↗

PubMed1997

Effects of IL-4 on antigen-induced production of eosinophil chemotactic activity from human mononuclear leukocytes.

The effect of IL-4 on antigen-induced production of eosinophil chemotactic factors (ECF) from human peripheral blood mononuclear cells (PBMC) was examined. Antigen-induced ECF production was enhanced in a dose-dependent manner when PBMC were pretreated with IL-4. The most potent enhancement was induced by IL-4 at a concentration of 30 U in tuberculin-sensitive PBMC, and 3 U in Dermatophagoides farinae (Df)-sensitive PBMC. A short period of pretreatment (30 min to 3 h) was sufficient for the enhancement, whereas a longer period of treatment was less effective. IL-4 pretreatment suppressed PPD-induced IFNgamma and IL-5 production but enhanced ECF production. Furthermore, we found that Df induced IL-5 but not IFNgamma production from PBMC, and that IL-5 production was not affected by pretreatment with IL-4. Next, experiments were done to clarify whether the ECF produced by PPD-stimulated PBMC was different from that produced by Df-stimulated PBMC. It was thus found that the pI of both ECF was at about pH 7.0 and that unlike chemokines such as RANTES and eotaxin, they had no affinity for heparin.

Antigens↗

PubMed1997

Expression of apoptosis-related antigen on eosinophils in chronic eosinophilic pneumonia.

We examined the expression of apoptosis-related antigens Fas and bcl-2 on eosinophils from peripheral blood (PB) and bronchoalveolar lavage (BAL) in patients with chronic eosinophilic pneumonia (CEP). The expression of those antigens was assessed before and after culture with or without eosinophil chemotactic factors derived from an established T-cell line (STO-2-derived ECFs; ECF-PI5, 6, 7, 8, and 9), granulocyte-macrophage colony stimulating factor, and interleukin 5 (IL-5). We found that the expression of these antigens on eosinophils from PB increased after 24 h culture without any stimulation. In contrast, little or no change was observed even after 24 h culture in eosinophils from BAL. All STO2-derived ECFs and IL-5 suppressed Fas expression on eosinophils from PB. Furthermore, we found that eosinophils which were attracted by ECF-PI9 expressed Fas and bcl-2 more highly than those attracted by other ECFs and IL-5. Such a heterogeneous response of eosinophils to respective ECFs suggests the possibility of a heterogeneous population of eosinophils in patients with CEP.

Adult↗

PubMed1997

Anti-asthma effect of an antiviral drug, acyclovir: a clinical case and experimental study.

BACKGROUND: Although acyclovir (9-(2-hydroxyethoxymethyl) guanine) is an antiviral drug that inhibits DNA polymerase of herpes virus, we have had the experience of an asthmatic patient's peak flow rate being improved by oral administration of acyclovir. OBJECTIVE: The aim of this experiment is whether acyclovir has anti-asthma effects using an asthma model in guinea-pigs. METHODS: The airway response was induced by a single inhalation of calcium ionophore A23187 (2 mg/mL). The airway obstruction was estimated by the ratio of expiration to inspiration time (E/I). The peribronchial eosinophil infiltration and eosinophil influx into bronchoalveolar lavage (BAL) fluid 7 h after the inhalation were also examined. To assess the effects of acyclovir (1, 10, and 100 mg/kg), aminophylline (20 mg/kg) and pemirolast potassium (TBX, 20 mg/kg) on A23187-induced asthmatic response, the drugs were intraperitoneally administered before the inhalation. RESULTS: The immediate airway obstruction was significantly suppressed by acyclovir (10 mg/kg) and aminophylline, whereas different doses of acyclovir (1 and 100 mg/kg) and TBX showed only a small inhibitory effect on the airway obstruction. On the other hand, the peribronchial eosinophilia was most successfully inhibited by TBX. Acyclovir (10 mg/kg) and aminophylline also suppressed the eosinophilia significantly. Furthermore, acyclovir significantly suppressed eosinophil influx into BAL fluid, whereas aminophylline and TBX weakly suppressed the influx. CONCLUSION: These results suggest that acyclovir exhibits not only antiviral but also antiasthma activity.

Acyclovir↗

PubMed1996

Heterogeneous chemotactic response of eosinophils from patients with atopic dermatitis to eosinophil chemotactic factors.

The chemotactic response of eosinophils from 16 patients with atopic dermatitis (AD) to 5 eosinophil chemotactic factors (ECFs) were examined to clarify whether the response is associated with the clinical severity of AD. The factors included ECF-P15, -P16, -P17, -P18 and -P19 and were derived from a T cell line, STO-2. The patients were divided into 2 groups according to the percentage migration of eosinophils produced by the ECFs: a high-responding group (migration > 40%), and a low-responding group (migration < 30%). In a statistical analysis, eosinophils from patients with AD and atopic respiratory diseases (ARD) were found to be high-responding and those from patients with AD alone low-responding (p < 0.01). In a comparison of the chemotactic response of eosinophils from patients with AD alone at remission and at exacerbation, the percentage migrations in response to ECF-P15 and ECF-P16 at exacerbation were significantly higher than that at remission (p < 0.05). It is thus suggested that this type of heterogeneous response of eosinophils to STO-2-derived ECFs could provide a useful tool for evaluation of disease severity in patients with AD.

Adolescent↗

PubMed1996

Heterogeneity of eosinophils in chronic eosinophilic pneumonia.

It has previously been shown that patients with chronic eosinophilic pneumonia can be divided into 2 groups according to the chemotactic response of their eosinophils to 5 different eosinophil chemotactic factors (ECFs) and laboratory findings. In contrast, eosinophils obtained by bronchoalveolar lavage from both groups responded to all 5 ECFs. The correlation between the two groups and the expression of several antigens (VLA-4, CD69, ICAM-1 and CD11b) on eosinophils. The VLA-4 expression of group 1 eosinophils was higher than that of group 2 eosinophils. More interestingly, eosinophils that migrated towards ECF-PI9 expressed less CD69 than those that migrated towards other STO-2-derived ECF. The heterogeneous response of eosinophils to STO-2-derived ECFs suggests that the population of eosinophils is heterogeneous.

Antigens, CD↗

PubMed1995

Characterization of antineutrophil antibodies in patients with neutropenia associated with nutritional copper deficiency.

Six antineutrophil antibody (ANA)-positive patients with copper deficiency were classified into two groups; those with (group A, n = 3) and those without (group B, n = 3) neutropenia. The percent binding of ANA for normal peripheral neutrophils was similar in both groups (83.5 +/- 7.2 vs. 79.1 +/- 10.5%). The percent binding of sera to cultured promyelocytic leukemia cells (HL-60) was increased in group A (from 3.7 +/- 3.2 to 12.2 +/- 2.3%) but not in group B (from 65.3 +/- 21.7 to 40.7 +/- 6.3%) after stimulation of HL-60 with DMSO. The stimulated HL-60 cells expressed CD 16 and CD 11b antigens. In the presence of monoclonal antibody for CD 16, the titer of ANA was nil in group A and unchanged in group B. Thus, ANA of patients with neutropenia may recognize mainly the CD 16 antigen, the Fc gamma receptor III of neutrophils.

Adolescent↗

PubMed1995

Chemotactic heterogeneity of eosinophils in idiopathic pulmonary eosinophilia.

Heterogeneity in the chemotactic response of eosinophils to 5 T cell line eosinophilic chemotactic factors (ECFs) was assessed in 5 patients with idiopathic pulmonary eosinophilia. Eosinophils from 2 patients responded to all 5 ECFs (group 1), whereas eosinophils from the other 3 patients responded to ECF-PI 5, PI 6, PI 7 and PI 8 but failed to respond to ECF-PI 9 (group 2). It was further found that group 1 showed an elevated level of lactate dehydrogenase and a positive tuberculin reaction, whereas group 2 showed neither. The effects of steroid therapy on the chemotactic responses of eosinophils were also examined. In group 1, the chemotactic response of eosinophils to ECF-PI 9 was significantly diminished after therapy; in contrast it was elevated in group 2. This change was accompanied by resolution of both clinical symptoms and pulmonary infiltration of eosinophils. These findings suggest that pulmonary eosinophilia can be divided into two types on the basis of eosinophil chemotactic response and laboratory findings. The heterogeneous responses of eosinophils to ECFs may provide a useful marker for classification of pulmonary eosinophilia and evaluation of therapy.

Adult↗

PubMed1994

Variations of hepatitis B virus precore/core gene sequence in acute and fulminant hepatitis B.

Variations of the hepatitis B virus (HBV) precore/core sequence has been shown to play a role in the development of active liver disease in chronic hepatitis B. Whether this is also an important viral factor in the pathogenesis of acute and fulminant hepatitis B is unknown. To determine the precore/core gene sequence in patients with acute and fulminant hepatitis B, 11 patients with fulminant hepatitis B and seven patients with acute hepatitis B were studied. The sequences of precore/core gene were determined by direct sequencing of the polymerase chain reaction amplicons generated from the HBV isolated from patients' serum. For the 11 patients with fulminant hepatitis B, the precore/core regions were successfully amplified in 10 patients. Eight patients exhibited precore stop codon mutations. In addition, nine of the 10 fulminant hepatitis B patients had frequent nucleotide substitutions with corresponding changes in the predicted amino acid sequences in the mid-core and the 5' terminus region of the core gene. In contrast, precore stop codon mutants were not detected, and variations of the HBV core gene were minimal in patients with acute hepatitis B. The association of HBV precore mutants and HBV core gene variations with fulminant hepatitis B and not acute hepatitis B suggested that these variations may be important in modulating the clinical course of HBV infection.

Acute Disease↗

PubMed1994

Production of fibroblast proliferative cytokines from T lymphocytes stimulated by a B cell lymphoma line and their functional heterogeneity.

Human mononuclear leukocytes (MNL) produced several factors with fibroblast proliferation activity (FPA) for HFL-1, a human lung fibroblast cell line, when MNL were cocultured with irradiated BALL-1, a B cell lymphoma line (BCLL), but not with other BCLL. The cellular source of BALL-1-induced FPA seemed to be CD4-positive T lymphocytes. On isoelectric electrophoresis, major activity of BALL-1-induced FPA was detected in the fractions around pH 4-5, and minor activity was present in the fractions around pH 6-7. Major BALL-1-induced FPA consisted of at least 4 different fibroblast proliferation factors (FPFs) according to their molecular weight; 320-600 kDa (P-I), 50-110 kDa (P-II), 22-38 kDa (P-III) and 4.6-11 kDa (P-IV). P-I had affinity to heparin though the rest had little or no affinity. FPA of P-I was suppressed by an antibody against acidic FGF, and FPA of P-III was suppressed by an antibody against IL-6. On the other hand, FPA of P-II and P-IV was suppressed by none of the antibodies against cytokines with FPA, such as FGF, IL-4, IL-6, IFN-gamma, TGF-beta and TNF-alpha. It was thus suggested that P-I was acidic FGF, that P-III was IL-6, and that P-II and P-IV were different cytokines from those described above. Furthermore, it was found that P-II and P-IV failed to exhibit proliferation activity for human umbilical vein endothelial cells (HUVEC).(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

PubMed1994

Colonic lysozymes of rabbit (Japanese white): recent divergence and functional conversion.

Lysozyme was extracted from the feces of rabbit (Japanese White) with 2.5% acetic acid and purified by ion-exchange chromatography. Subsequent ion-exchange HPLC at pH 4.0 revealed the presence of two isozymes, namely rabbit colonic lysozymes 1 and 2. The amino acid sequences of these lysozymes were determined. The colonic lysozymes 1 and 2 showed 98% identity with each other and 94 and 95% identities with rabbit kidney lysozyme, respectively. The very high identities between kidney and colonic lysozymes indicate that the colonic isozymes diverged from the conventional kidney lysozyme very recently, probably after the divergence of rabbit from other rodents, accompanying the gene duplication. Despite the small changes in the sequences, the enzymatic properties of colonic lysozyme differ from those of the kidney lysozyme. The activity of the colonic lysozyme against Micrococcus luteus cells showed a narrow and acidic pH optimum, in contrast to the wide and high pH optimum of the kidney lysozyme. Changes in the enzymatic properties are analogous to those of the ruminant stomach lysozymes and may implicate adaptive evolution in the functional conversion of rabbit colonic lysozymes in gut.

Adaptation, Physiological↗

PubMed1994

A B cell lymphoma line, BALL-1 stimulates T cells to produce a unique eosinophil chemotactic factor.

Human mononuclear leukocytes (MNL), probably OKT4-positive T cells, produced an eosinophil chemotactic factor (ECF) when they were cocultured with irradiated BALL-1, a B cell lymphoma line. Treatment of MNL, with anti-IL-2 antibody failed to suppress BALL-1-induced ECF production. Periodate-lysine-paraformaldehyde-fixed but not acetone- and ethanol-fixed BCLL induced evident ECF production. These results suggested that some cell surface molecules play a role in the induction of ECF production. Isoelectric point of BALL-1-induced ECF was around pH7, whereas that of IL-2-induced ECF was around pH 5. The molecular weight of BALL-1-induced ECF was between 10 and 30 kD. Although a combination of MoAb against IL-3, IL-5, and GM, CSF suppressed the activity of IL-2-induced ECF, it failed to suppress that of BALL-1-induced ECF. Furthermore, BALL-1-induced ECF suppressed fMLP-induced respiratory bursts of eosinophils, while IL-2-induced ECF failed. We propose that at least one reason for eosinophil infiltrate into the stroma of tumors is that the tumor cells stimulate T cells to produce BALL-1-induced ECF, and the eosinophils attracted by the ECF exhibit different functions from those by other ECF.

Chemotactic Factors, Eosinophil↗