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Biomedical subjects

V Barak

Publications and source records attributed to V Barak.

At least 73 records · Page 4Linked to original sources
PubMed1996

Identification of interleukin-2 in human peripheral blood eosinophils.

Interleukin-2 (IL-2) is an essential growth factor for T cells. Previous studies have shown that human peripheral eosinophils respond to IL-2 in chemotaxis and express the IL-2 receptor (CD25). In addition, eosinophils have been shown to transcribe messenger RNA for IL-2. The aim of the present study was to determine whether eosinophils translate mRNA for IL-2 and to determine the site of intracellular localization. By immunocytochemistry, an average of 9% of cells showed cytoplasmic staining for IL-2 in freshly isolated unstimulated blood eosinophils obtained from asthmatic subjects who were not receiving oral corticosteroid treatment (n = 5). Freshly isolated, disrupted, highly purified eosinophils (> 99%, by CD16- immunomagnetic selection) contained an average of 6 pg/10(6) cells of IL-2 measured by a specific enzyme linked immunosorbent assay (ELISA) (n = 7). Purified eosinophil incubated with serum-coated Sephadex beads showed an increase in the amount of intracellularly-retained IL-2 (26.2 +/- 7.2 pg/10(6) cells) with some evidence for release of this cytokine but only in three out of six eosinophil preparations (range 1.3-5.8 pg/10(6) cells). The intracellular localization of IL-2 was determined by fractionation of the cells on a linear (0-45%) Nycodenz gradient in sucrose buffer followed by detection of IL-2 in the fractions using an IL-2-specific ELISA and dot blotting. The majority of the IL-2 detected co-eluted with known eosinophil granule markers (i.e. major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil peroxidase (EPO) and beta-hexosaminidase) but small quantities were also detected in the cytosolic (lactate dehydrogenase-(LDH) associated) and membrane (CD9+) fractions. Immunogold labelling of intact eosinophils using an anti-IL-2 monoclonal antibody confirmed IL-2 immunoreactivity in association with the eosinophil crystalline granule cores. These data are consistent with the hypothesis that eosinophils synthesize, release and store IL-2 largely within cystalloid granules. This stored IL-2 may serve as a reservoir for rapid release of IL-2 in inflammatory reactions associated with eosinophilia.

Asthma↗
PubMed1996

Characterization of intraperitoneal cytokines and nitrites in women with severe ovarian hyperstimulation syndrome.

OBJECTIVE: To assess the potential involvement of cytokines and nitrites in the hyperpermeability characterizing the ovarian hyperstimulation syndrome (OHSS). DESIGN: A controlled clinical study comparing peritoneal fluid (PF) from patients with severe OHSS and from non-OHSS controls. SETTING: Women hospitalized with severe OHSS in three tertiary medical centers. PATIENTS: Twelve patients with severe OHSS necessitating paracentesis and 20 non-OHSS controls. INTERVENTIONS: The criteria for ultrasound-guided paracentesis were tense ascites, hydrothorax, hemoconcentration, or oliguria. MAIN OUTCOME MEASURES: Interleukin (IL) 1 beta IL-1 receptor agonist, IL-2, IL-6, IL-8, and tumor necrosis factor alpha (TNF alpha) levels in PF were assayed by ELISA; nitrites were measured by the "Griess" reaction. Estradiol and P were determined by RIA. RESULTS: Ovarian hyperstimulation syndrome patients had significantly higher PF IL-6 (3,523 versus 30 pg/mL), TNF alpha (14 versus 4.2 pg/mL), and IL-8 (1,695 versus 900 pg/mL). In the serum, only IL-6 levels were significantly higher (375 versus 11 pg/mL). Conversely, nitrite levels were significantly lower in PF of OHSS patients (0.5 versus 34 nmol/mL). Interleukin 1 levels were higher and IL-1 receptor antagonist levels were lower in OHSS patients, suggesting potentially increased biologic potency of IL-1. CONCLUSION: These findings suggest that these substances could be involved in mediating the capillary hyperpermeability characterizing this syndrome.

Ascitic Fluid↗
PubMed1995

Elevated inflammatory cytokine levels in bone marrow graft rejection.

Graft rejection and graft failure represent major obstacles in allogeneic bone marrow transplantation (BMT). Cytokines possibly play a central role in the inflammatory and allospecific components of allograft rejection. Therefore, we evaluated inflammatory cytokine levels following BMT in 12 consecutive patients with graft rejection (GR). Seven of the patients underwent BMT from siblings (6 matched and 1 mismatched), 4 patients received bone marrow from other family members (3 mismatched and 1 matched), and 1 patient underwent HLA-matched unrelated BMT. Nine of 12 had a sex-mismatched BMT and 5/12 had an ABO-mismatched BMT. Nine of 12 underwent T cell-depleted (Campath anti-CDw52 moAb) BMT. Rejection was defined as marrow hypoplasia with a peripheral white blood cell count < 0.5 x 10(9)/L 21 days after BMT, in conjunction with the absence of donor cells by polymerase chain reaction analysis using a sex-mismatched probe and/or a tumor-specific probe (BCR/ABL). Twenty-five patients who underwent uneventful BMT with no GR served as controls. The levels of tumor necrosis factor (TNF), interleukin-6 (IL-6), and interleukin-1 (IL-1) were evaluated by a high sensitive RIA or an enzyme immunoassay. The levels of TNF and IL-6 were found to be higher in 10/12 and 7/7 evaluated GR patients, respectively, as compared with controls (P < 0.05). The level of IL-1 was high only in 2/12 patients. TNF elevation occurred in all patients immediately after GR. TNF and IL-6 levels were significantly higher for patients with early rejection (< 35 days after BMT) as compared with patients with late rejection (> 35 days after BMT) (P < 0.049 and P < 0.006, respectively). Eight patients engrafted after the second transplant (2 only transient). All 6 patients with stable engraftment are alive (4 with basic disease), while the 4 patients who did not engraft and the 2 patients with only transient engraftment died. In the 6 patients with no engraftment or only transient engraftment, the elevated TNF levels remained high; in the 6 patients who had stable engraftment after retransplant, TNF levels, but not IL-6 levels, decreased. In conclusion, a majority of the patients with GR displayed high levels of inflammatory cytokines (TNF and IL-6). Dysregulation of inflammatory cytokines may be involved in the pathogenesis of GR.

ABO Blood-Group System↗
PubMed1995

Histamine enhances granulocyte-macrophage colony-stimulating factor and interleukin-6 production by human peripheral blood mononuclear cells.

The effect of histamine on the production of cytokines by subpopulations of mononuclear cells was studied. A 3.5-fold increase in the number of myeloid colony-forming units (CFU-C) was observed when bone marrow cells were cultured in the presence of conditioned medium prepared from nonadherent mononuclear cells cultured with 10(-4) M histamine (CM-histamine) compared with phosphate-buffered saline (CM-PBS). Using ELISA and radioimmunoassay kits, histamine was found to enhance the production of GM-CSF (9.6-fold) and IL-6 (8.2-fold) by mononuclear cells but not by nonadherent cells or large granular lymphocytes. Anti-GM-CSF and anti-IL-6 antibodies markedly blocked cytokine activity in CM-PBS, whereas the blocking effect in CM-histamine was moderate, indicating enhanced GM-CSF and IL-6 activity in CM-histamine. No GM-CSF or IL-6 levels could be detected in CM-histamine or CM-PBS prepared from CD3+, CD4+, or CD8+ lymphocytes. Preincubation of CM-histamine with H1 and H2 receptor antagonists resulted in complete blocking of the histamine-enhanced colony-stimulating activity. We conclude that histamine is able to activate human mononuclear cells to generate cytokines such as GM-CSF and IL-6 via H1 and H2 receptors.

Antibodies↗
PubMed1995

High-efficiency retroviral gene transfer into murine high-proliferative-potential cells cycle-activated by cytosine arabinoside.

We investigated cytosine arabinoside (Ara-C) as a potential agent for in vivo cycle activation of hematopoietic progenitors for the purpose of retroviral-mediated gene transfer. C57Bl mice were treated intraperitoneally with one of three regimens of Ara-C: a single 1,750 mg/kg dose (regimen 1), a 1,750 mg/kg dose on day 0, and a 1,500 mg/kg dose on day 2 (LD50) (regimen 2), or a 1,750 mg/kg dose on day 0 and a 1,500 mg/kg dose on day 3 (regimen 3). The high-proliferative-potential cells (HPPC)/10(5) cells were 47.0 +/- 7.5 pretreatment. The post-treatment HPPC cloning efficiencies were 40.6 +/- 3.4, 83.6 +/- 6.1, and 20.4 +/- 3.2 HPPC/10(5) cells on days 1, 2, and 4, respectively, with regimen 1; 60.0 +/- 7.9, 194.0 +/- 9.6, and 103.0 +/- 11.0 HPPC/10(5) cells 1, 2, and 4 days after the second Ara-C dose, respectively, with regimen 2; and 266 +/- 13.4, 132 +/- 23.9, and 118.0 +/- 5.7/10(5) cells 1, 2, and 4 days after the second Ara-C dose, respectively, with regimen 3. The transduction efficiency of HPPC from untreated animals with N2 viral supernatant was 4.9 +/- 5.8%.(ABSTRACT TRUNCATED AT 250 WORDS)

3T3 Cells↗
PubMed1995

Imbalance of immune responses in patients with chronic and widespread fungal skin infection.

Fungal infections of the skin are caused by dermatophyte fungi. Infections can be acute and inflammatory or chronic and non-inflammatory; it is believed that cell-mediated immunity is the cornerstone of host defence and is instrumental in the eradication of the infection. We describe here parameters of the immune response of a group of patients who although not immunocompromised, suffered from widespread and chronic infections. All patients lacked a specific delayed-type hypersensitivity (DTH) response; however, their in vitro lymphocyte proliferation in response to Trichophyton rubrum extract and to other fungal antigens was normal. The patients were not atopic by clinical history, and yet had high levels of non-specific IgE and of T. rubrum-specific IgG4. Taken together, the results of this study suggest that the group of patients studied suffered from an immune imbalance which has characteristics of a Th2-type response.

Adult↗
PubMed1995

Changes in interleukin-1 beta and soluble interleukin-2 receptor levels in CSF and serum of schizophrenic patients.

Some evidence points towards a possible autoimmune role in the aetiology of schizophrenia. Experimental findings provide contradictory results regarding abnormalities in cytokine production in this disorder. In the present study we tested the production of cytokines in CSF and serum in 16 schizophrenic patients and 10 healthy controls (tumor necrosis factor alpha - TNF alpha; interleukins IL-1 beta, IL-2, IL-6, soluble IL-2 receptor). Cytokine levels were evaluated by radioactively-labeled antibodies (IL-1 beta, IL-2, IL-6), by enzyme-linked immunoassay (TNF) and by a sandwich enzyme immunoassay (soluble IL-2 receptor). No significant differences were found in either CSF fluid or serum levels of TNF and IL-2 or IL-6. Interleukin-1 beta was significantly decreased in patients' CSF and serum as compared to controls. Soluble interleukin-2 receptor levels were decreased in CSF of patients, but highly increased in their serum in comparison with controls. Changes in various cytokine levels in CSF fluid and serum of schizophrenic patients probably reflect interrelated process of growth, degeneration or neuroimmunological abnormalities, which may all play a role in the pathophysiology of schizophrenia. The present study supports evidence for change in immune activation, probably of peripheral origin, in schizophrenic patients.

Adult↗
PubMed1995

Cytokine dysregulation in chronic graft versus host disease.

Cytokines play a key role in the pathogenesis of chronic Graft versus Host Disease (cGVHD) and various studies have shown abberant production of cytokines by immune cells from GVHD patients. Based on these findings and others showing that high TNF levels precede the development of GVHD, we evaluated inflammatory cytokine levels following BMT and during the development of cGVHD. In this study, patients undergoing bone marrow transplantation (BMT) who consequently developed chronic GVHD were analyzed as to their cytokine production during cGVHD and this was correlated with their clinical manifestations. A positive correlation was found between the severity as well as the number of major clinical complications and high levels of inflammatory cytokines (IL-1 beta IL-6 and TNF alpha) compared to control patients or to normal donors. Patients undergoing BMT who did not develop GVHD, did not produce high levels of IL-1 beta IL-6 or TNF. High levels of cytokines may be used as a tool for assessing novel therapeutic modalities and response to GVHD treatment.

Adolescent↗
PubMed1994

Cytokine and growth factor gene expression by bone marrow stroma of mice with damaged hematopoiesis and during regeneration.

A study of gene expression of GM-CSF, IL-3, c-kit ligand, and IL-1 by bone marrow stromal cells of mice who were treated with an LD50 cytosine arabinoside (Ara-C) dose was carried out. It was shown previously that this dose causes extensive hematopoietic damage which is followed by regeneration in surviving mice. Using PCR, we demonstrated GM-CSF and IL-1 expression by adherent cells taken from marrow fibroblast layers following Ara-C-induced hematopoietic damage and during marrow regeneration, while expression in control layers was not detected. The IL-3 gene was not expressed either by layers of Ara-C-treated mice or by controls, probably due to the absence of T-lymphocytes in 2-4 week old cultures. The c-kit ligand gene was expressed by layers during marrow regeneration and by control layers, but was absent during the stage of hematopoietic damage. In parallel, in vitro cytokine production was evaluated. While IL-3 and GM-CSF were not present in the conditioned medium of marrow fibroblast layers either from Ara-C-treated mice or controls, IL-1 was found in low concentrations in cultures from Ara-C-treated animals. We conclude that GM-CSF, c-kit ligand and IL-1 have important roles in sustaining marrow regeneration following extensive damage. The role of IL-3 in marrow regeneration cannot be assessed in fibroblast layers of 2-4 week incubation where T-lymphocytes are generally absent.

Animals↗
PubMed1994

Interleukin-1 favours the in vitro development of type 2 T helper (Th2) human T-cell clones.

The effects exerted by interleukin-1 (IL1) on the growth and differentiation of human Th1 and Th2 cells were examined. Neither IL1 nor the IL1 receptor antagonist (IL1ra) had detectable activity toward the antigen- or anti-CD3 antibody-induced proliferative response of already established type 1 T helper (Th1) or type 2 T helper (Th2) clones. Moreover, neither exogenous IL1 addiction to, nor neutralization of, endogenously produced IL1 in bulk cultures before cloning changed the Th1-like cytokine profile of PPD-specific T-cell lines. Likewise, IL1 addition in bulk culture before cloning did not significantly affect the Th2-like cytokine profile of Der.p.I-specific T-cell lines (Dermatophagoides pteronyssinus group I). However, Der.p.I-specific T-cell lines, derived in the presence of anti-IL1 Ab, IL1ra or the M-20 IL1 inhibitor, exhibited the reduced ability to produce IL4 and an increased ability to produce interferon gamma (IFN gamma). More importantly, Der.p.I-specific T-cell lines derived in the presence of IL1ra developed into Der.p.I-specific CD4+ T-cell clones showing a Th0/Th1-like, instead of a Th0/Th2-like, cytokine profile. These data suggest that IL1 is not required for the growth of already established human Th1 or Th2 CD4+ T-cell clones and has no regulatory effects on the in vitro development of Th1-like cells, but it plays a critical role in the development of Th2-like cells.

Animals↗
PubMed1994

Treatment of chronic myelogenous leukemia with recombinant human interleukin-2 and interferon-alpha 2a.

The safety, tolerance, and clinical effects of combined therapy with recombinant interferon-alpha (IFN-alpha) and interleukin-2 (rIL-2) administered subcutaneously for 2 courses of 4 weeks each, with 4 weeks interval between courses, given as outpatient therapy have been assessed in 10 patients with Philadelphia chromosome (Ph1)-positive chronic myelogenous leukemia (CML). All patients were previously treated with conventional chemotherapy and 3 failed to respond to IFN-alpha administered prior to our study. Median duration of disease from diagnosis was 36 months. Seven patients were in first chronic phase and the other 3 were in blast crisis, second chronic phase, and relapse post-bone marrow transplantation (BMT), respectively. Hematological response (median follow-up 16 months) was observed in 9 patients, with a decline in number of white blood cells and platelets. Elimination of Ph1 was observed in the patient who relapsed post-BMT with complete elimination bcr/abl RNA by polymerase chain reaction. Rebound lymphocytosis and eosinophilia were observed in most of the patients. Toxicity was acceptable. The main adverse effects were fever, chills, fatigue, anorexia, nausea, and vomiting. The side effects were reversible and no interruption of treatment was required. There was no treatment-related hospitalization or deaths. These data suggest that simultaneous subcutaneous IFN-alpha and rIL-2 home therapy is feasible, reasonably well tolerated, and potentially beneficial in CML patients. These observations may have important implications for the treatment of minimal residual disease following allogeneic and autologous marrow transplantation.

Adolescent↗
PubMed1994

High concentration of soluble interleukin-2 receptors in ejaculate with low sperm motility.

The various cytokines are involved in infection and immunological reactions and thus may be involved in impairment of sperm function. The present study determined the concentrations of interleukin-1, interleukin-6 and soluble interleukin-2 receptors in ejaculates of normal donors and patients suffering from pure asthenozoospermia and patients suffering from oligoteratoasthenozoospermia. Ejaculates of patients attending the fertility clinic in Hadassah Mount Scopus Hospital, Israel, were evaluated. The patients were divided into three groups: (i) controls (n = 20), (ii) pure asthenozoospermia (n = 30), (iii) oligoteratoasthenozoospermia (n = 36). Significantly higher concentrations of soluble interleukin-2 receptors were found in the ejaculates of patients with pure asthenozoospermia 2243.1 +/- 473.6 mu/ml (mean +/- SE) as compared with controls 673.5 +/- 281.3 mu/ml (P < 0.05) and oligoteratoasthenozoospermic patients 1012.3 +/- 206.9 mu/ml (P < 0.05). Interleukin-1 and interleukin-6 concentrations were comparable in all groups studied. Our results show that human ejaculates contain interleukin-1, interleukin-6 and soluble interleukin-2 receptors. High concentrations of soluble interleukin-2 receptors in the ejaculates of asthenozoospermic patients may be related to either infectious or immunological processes.

Humans↗
PubMed1994

The secretion of PGE2, IL-1 beta, IL-6, and TNF alpha by adherent mononuclear cells from early onset periodontitis patients.

The secretion of prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF alpha), interleukin 1 beta (IL-1 beta), and interleukin 6 (IL-6) by adherent mononuclear cells (AMNC) from 28 patients with early-onset periodontitis was studied. The early onset-periodontitis patients consisted of 12 patients with localized juvenile periodontitis (LJP) and 16 patients with severe generalized periodontitis (SGP). The AMNC responses to different concentrations of lipopolysaccharide (LPS) (E. coli) were determined in these 28 patients and compared to 14 healthy controls. Mediator levels in the supernatant were measured using radioimmunoassays for PGE2, IL-1 beta, and IL-6 determination and an enzyme linked immunosorbent assay for TNF alpha levels. The mean age of the patients was 19.9 years for the LJP group, 30.4 years for SGP, and 28.0 years for the controls. The mean number of teeth per patient with attachment loss of > 6 mm was 4.75 in the LJP patients and 17.3 in the SGP group. In the absence of LPS, LJP AMNC secreted significantly more PGE2 than unstimulated control or SGP AMNC, while similar baseline amounts of IL-1 beta, IL-6, and TNF alpha were secreted by AMNC from the 3 patient groups. LPS stimulation resulted in the dose-dependent secretion of significantly higher levels of PGE2 by LJP AMNC compared to SGP AMNC which in turn secreted significantly more than controls. TNF alpha secretion by LJP monocytes was significantly greater than the SGP and the control groups while IL-1 beta secretion by the SGP AMNC was depressed compared to the other two patient groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗