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Wagdy R, Assem H, Abd-Elmohsen AM, Fata A, Gendy WE, Gaber M. Altered ventricular longitudinal strain in children with sickle cell disease: Role of TGF-β and IL-18. Pediatr Blood Cancer 2024; 71:e30762. [PMID: 37933422 DOI: 10.1002/pbc.30762] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 10/02/2023] [Accepted: 10/19/2023] [Indexed: 11/08/2023]
Abstract
BACKGROUND Cardiovascular involvement in sickle cell disease (SCD) has a great impact on patients' morbidity and mortality. Recently, interleukin-18 (IL-18) and transforming growth factor beta (TGF-β) were suggested as potential biomarkers for sickle cell cardiomyopathy. Global longitudinal strain (GLS) is a reliable early parameter for estimation of deformed myocardium. This study evaluated the role of TGF-β and IL-18 as risk indicators of altered strain in patients with SCD. METHODS Forty children with SCD (age >5 years) and 40 healthy children as controls, matched in age and sex, were enrolled in the study. All participants were subjected to clinical examination, complete blood count, serum ferritin, TGF-β, IL-18, and assessment of cardiac function by echocardiography. RESULTS TGF-β, IL-18, and lactic acid dehydrogenase (LDH) were significantly higher among cases (mean age: 10.6 ± 3.5 years) when compared to controls (p < .001), at cutoff values 41.7 ng/mL, 128.9 pg/mL, and 340 unit, respectively. The LS of free wall of RV (FW-RV) was significantly lower among cases when compared to controls (-23.55% ± 5.55% vs. -28.73% ± 2.43%, p < .001). Free wall longitudinal strain of the right ventricle (FWLS-RV) was significantly correlated to IL-18 and LDH (p < .001), while GLS-RV was significantly correlated to TGF-β. The GLS-LV was correlated to frequency of vaso-occlusive crises (VOCs) per year (p < .001). Diastolic function, E/A of LV, and RV were negatively correlated to the hemoglobin and serum ferritin levels. CONCLUSIONS The TGF-β, IL-18, and LDH along with frequent VOCs are correlated to altered LS, especially the right ventricle, and could serve as risk indicators for subclinical cardiomyopathy in children with SCD.
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Affiliation(s)
- Reham Wagdy
- Department of Pediatrics, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Hala Assem
- Department of Pediatrics, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Ali M Abd-Elmohsen
- Department of Pediatrics, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Aya Fata
- Department of Pediatrics, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Wessam El Gendy
- Department of Clinical Pathology, Faculty of Medicine, Alexandria University, Alexandria, Egypt
| | - Marwa Gaber
- Department of Cardiology, Medical Research Institute, Alexandria University, Alexandria, Egypt
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Gallegos JL, Taylor-Piliae RE, Pace TWW, Gallek MJ, Ritter L. Adiponectin, Interleukin-18 (IL-18), and Visceral Adipose Tissue in Filipino Americans: Biomarkers and Risk of Type 2 Diabetes. SAGE Open Nurs 2024; 10:23779608241272513. [PMID: 39139192 PMCID: PMC11320395 DOI: 10.1177/23779608241272513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 07/05/2024] [Accepted: 07/09/2024] [Indexed: 08/15/2024] Open
Abstract
Introduction Filipino Americans (FAs) are at high risk for developing type 2 diabetes despite other Asian phenotypes. Evidence suggests that pro-inflammatory interleukin-18 (IL-18) and anti-inflammatory adiponectin biomarkers associated with visceral adipose tissue (VAT) may explain this risk. Objectives This study aimed to quantify the biomarkers in relation to standard ranges of VAT or typical circulating concentration ranges reported in the literature of IL-18 and adiponectin, examine relationships of these markers, and determine if they were different among those participants without diabetes, prediabetes, and diabetes. Methods A cross-sectional study was used to enroll FAs without diabetes, prediabetes, or diabetes. VAT was measured using the InBody 570© Body Composition Analyzer. Blood samples were obtained to assess plasma concentrations of IL-18 and adiponectin using enzyme-linked immunosorbent assay. All analyses were conducted using a 5% type I error rate. Mean ±SD and percentages were used to describe the sample and data where appropriate. Pearson's correlations (R) were calculated to determine the relationships between VAT and IL-18 in each group. Analysis of variance was used to determine differences in VAT, IL-18, and adiponectin among groups. Further, nonparametric procedures examined the differences in adiponectin among those within groups. Results Seventy-five participants were enrolled. Biomarkers above the typical concentration range were observed for VAT, IL-18, and adiponectin. Adiponectin significantly differed among groups with lower values in the diabetes group vs. the nondiabetes group. Conclusions The findings indicate that while inflammation-related biomarkers, such as adiponectin, correlate with VAT and may serve as indicators of increased risk of type 2 diabetes in FAs, correlation alone does not establish causality.
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Affiliation(s)
| | | | - Thaddeus W. W. Pace
- Division of Biobehavioral Health Science, College of Nursing, University of Arizona
- Department of Psychiatry, College of Medicine, University of Arizona, Tucson, AZ, USA
- Department of Psychology, College of Science, University of Arizona, Tucson, AZ, USA
| | - Matthew J. Gallek
- School of Nursing, University of North Carolina Wilmington, Wilmington, NC, USA
| | - Leslie Ritter
- College of Nursing and Department of Neurology, University of Arizona, Tucson, AZ, USA
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Vecchié A, Bonaventura A, Toldo S, Dagna L, Dinarello CA, Abbate A. IL-18 and infections: Is there a role for targeted therapies? J Cell Physiol 2020; 236:1638-1657. [PMID: 32794180 DOI: 10.1002/jcp.30008] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/24/2020] [Accepted: 08/01/2020] [Indexed: 01/08/2023]
Abstract
Interleukin (IL)-18 is a pro-inflammatory cytokine belonging to the IL-1 family, first identified for its interferon-γ-inducing properties. IL-18 regulates both T helper (Th) 1 and Th2 responses. It acts synergistically with IL-12 in the Th1 paradigm, whereas with IL-2 and without IL-12 it can induce Th2 cytokine production from cluster of differentation (CD)4+ T cells, natural killer (NK cells, NKT cells, as well as from Th1 cells. IL-18 also plays a role in the hemophagocytic lymphohistiocytosis, a life-threatening condition characterized by a cytokine storm that can be secondary to infections. IL-18-mediated inflammation was largely studied in animal models of bacterial, viral, parasitic, and fungal infections. These studies highlight the contribution of either IL-18 overproduction by the host or overresponsiveness of the host to IL-18 causing an exaggerated inflammatory burden and leading to tissue injury. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the coronavirus disease 2019 (COVID-19). The damage in the later phase of the disease appears to be driven by a cytokine storm, including interleukin IL-1 family members and secondary cytokines like IL-6. IL-18 may participate in this hyperinflammation, as it was previously found to be able to cause injury in the lung tissue of infected animals. IL-18 blockade has become an appealing therapeutic target and has been tested in some IL-18-mediated rheumatic diseases and infantile-onset macrophage activation syndrome. Given its role in regulating the immune response to infections, IL-18 blockade might represent a therapeutic option for COVID-19, although further studies are warranted to investigate more in detail the exact role of IL-18 in SARS-CoV-2 infection.
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Affiliation(s)
- Alessandra Vecchié
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University, Richmond, Virginia
| | - Aldo Bonaventura
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University, Richmond, Virginia.,Department of Internal Medicine, First Clinic of Internal Medicine, University of Genoa, Genoa, Italy
| | - Stefano Toldo
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University, Richmond, Virginia
| | - Lorenzo Dagna
- Unit of Immunology, Rheumatology, Allergy and Rare Diseases, IRCCS San Raffaele Scientific Institute, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
| | - Charles A Dinarello
- Department of Medicine and Immunology, University of Colorado School of Medicine, Aurora, Colorado.,Department of Medicine, Radboud University Medical Center, Nijmegen, Netherlands
| | - Antonio Abbate
- Division of Cardiology, Department of Internal Medicine, Pauley Heart Center, Virginia Commonwealth University, Richmond, Virginia
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IL-35 and IL-18 Serum Levels in Children With Acute Lymphoblastic Leukemia: The Relationship With Prognostic Factors. J Pediatr Hematol Oncol 2020; 42:281-286. [PMID: 31764513 DOI: 10.1097/mph.0000000000001667] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Acute lymphoblastic leukemia (ALL) is the most common type of cancer among children. In this study, we investigated the serum levels of interleukin (IL)-35 and IL-18 in children with ALL to compare with healthy subjects and find their relationship with prognostic factors and response to therapy. IL-35 and IL-18 serum concentrations in 40 children diagnosed with ALL and 35 age-matched and sex-matched healthy children were measured using ELISA. The association between cytokine levels and patients' clinical and laboratory data were determined. A significant difference was found in IL-35 serum levels between the patients (3.6±1.5 ng/mL) and controls (2.5±1.8 ng/mL) (P=0.007). No significant difference in IL-18 serum levels between these groups was observed. A positive correlation between IL-35 and IL-18 levels was detected (P=0.001). The authors found that patients with lower platelet count had higher IL-35 concentration (P=0.003). By considering a cut-off value of 6.21 ng/mL (mean±2SD of controls) for IL-35, it was found that white blood cell (WBC) count was higher in patients with IL-35 >6.21 ng/mL (P=0.016), and the majority of these patients had T-ALL (P=0.01). Although the mean overall survival in patients with IL-35 >6.21 ng/mL was shorter (937±381 d) than in those with IL-35 ≤6.21 ng/mL (1567±103 d), but the result was not significant (P=0.1, log-rank test). The IL-18 level was associated with a lower hemoglobin level (P=0.027). These data suggested a role for IL-35 in ALL development. The significant relation of IL-35 to white blood cells and platelet counts may imply a possible influence of IL-35 on ALL prognosis.
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Oliveira ML, Akkapeddi P, Alcobia I, Almeida AR, Cardoso BA, Fragoso R, Serafim TL, Barata JT. From the outside, from within: Biological and therapeutic relevance of signal transduction in T-cell acute lymphoblastic leukemia. Cell Signal 2017. [PMID: 28645565 DOI: 10.1016/j.cellsig.2017.06.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological cancer that arises from clonal expansion of transformed T-cell precursors. In this review we summarize the current knowledge on the external stimuli and cell-intrinsic lesions that drive aberrant activation of pivotal, pro-tumoral intracellular signaling pathways in T-cell precursors, driving transformation, leukemia expansion, spread or resistance to therapy. In addition to their pathophysiological relevance, receptors and kinases involved in signal transduction are often attractive candidates for targeted drug development. As such, we discuss also the potential of T-ALL signaling players as targets for therapeutic intervention.
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Affiliation(s)
- Mariana L Oliveira
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Padma Akkapeddi
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Isabel Alcobia
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal; Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Afonso R Almeida
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Bruno A Cardoso
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Rita Fragoso
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - Teresa L Serafim
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal
| | - João T Barata
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Portugal.
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Peters CD, Jespersen B, Nørregaard R. AlphaLISA versus ELISA-based detection of interleukin 18 in healthy subjects and patients with end-stage renal disease. Scandinavian Journal of Clinical and Laboratory Investigation 2012; 72:583-92. [DOI: 10.3109/00365513.2012.713175] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Goto N, Tsurumi H, Kasahara S, Kanemura N, Hara T, Yasuda I, Shimizu M, Murakami N, Sawada M, Yamada T, Takemura M, Seishima M, Kito Y, Takami T, Moriwaki H. Serum interleukin-18 level is associated with the outcome of patients with diffuse large B-cell lymphoma treated with CHOP or R-CHOP regimens. Eur J Haematol 2011; 87:217-27. [DOI: 10.1111/j.1600-0609.2011.01649.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Monroy CM, Cortes AC, Lopez MS, D'Amelio AM, Etzel CJ, Younes A, Strom SS, El-Zein RA. Hodgkin disease risk: role of genetic polymorphisms and gene-gene interactions in inflammation pathway genes. Mol Carcinog 2011; 50:36-46. [PMID: 21061265 DOI: 10.1002/mc.20688] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Inflammation is a critical component of cancer development. The clinical and pathological features of Hodgkin disease (HD) reflect an abnormal immunity that results from cytokines secreted by Reed-Sternberg cells and the surrounding tumor. Numerous studies have reported the association between genetic polymorphisms in cytokine genes and the susceptibility to different hematologic cancers. However, the effects of such SNPs on modulating HD risk have not yet been investigated. We hypothesized that gene-gene interactions between candidate genes in the anti- and pro-inflammatory pathways carrying suspicious polymorphisms may contribute to susceptibility to HD. To test this hypothesis, we conducted a study on 200 HD cases and 220 controls to assess associations between HD risk and 38 functional SNPs in inflammatory genes. We evaluated potential gene-gene interactions using a multi-analytic strategy combining logistic regression, multi-factor dimensionality reduction, and classification and regression tree (CART) approaches. We observed that, in combination, allelic variants in the COX2, IL18, ILR4, and IL10 genes modify the risk for developing HD. Moreover, the cumulative genetic risk score (CGRS) revealed a significant trend where the risk for developing HD increases as the number of adverse alleles in the cytokine genes increase. These findings support the notion that epigenetic-interactions between these cytokines may influence pathogenesis of HD modulating the proliferation of regulatory T cells. In this way, the innate and adaptative immune responses may be altered and defy their usual functions in the host anti-tumor response. Our study is the first to report the association between polymorphisms in inflammation genes and HD susceptibility risk.
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Affiliation(s)
- Claudia M Monroy
- Department of Epidemiology, The University of Texas M.D. Anderson Cancer Center, Houston, Texas 77030-1439, USA
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9
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Characterization of monoclonal antibodies against goat interleukin-18 and their application in the measurement of goat interleukin-18 in LPS-stimulated peripheral blood mononuclear cells by sandwich ELISA. Vet Immunol Immunopathol 2010; 138:235-8. [PMID: 20692710 DOI: 10.1016/j.vetimm.2010.07.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 07/13/2010] [Accepted: 07/13/2010] [Indexed: 11/24/2022]
Abstract
In order to develop a specific assay for the measurement of goat IL-18 level, two stable hybridoma cell lines were established which secreted IgG1 monoclonal antibodies (mAbs) against goat IL-18. Specific binding of two mAbs named 2E8 and 4C4 to recombinant goat IL-18 expressed in Escherichia coli was demonstrated in an ELISA and Western blotting. Results also showed that mAbs 2E8 and 4C4 bound to distinct epitopes in the ELISA additivity test. These two mAbs were applied in IFA analysis for the detection of goat IL-18 expressed in 293FT cells and in the sandwich ELISA for the measurement of goat IL-18 levels in LPS-stimulated PBMC. Results from this study demonstrated that mAbs against goat IL-18 recognize bovine and human IL-18 and could be used to measure IL-18 levels in different inflammations or immune responses in future studies.
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Chen AH, Tsau YW, Lin CH. Novel methods to identify biologically relevant genes for leukemia and prostate cancer from gene expression profiles. BMC Genomics 2010; 11:274. [PMID: 20433712 PMCID: PMC2873479 DOI: 10.1186/1471-2164-11-274] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Accepted: 04/30/2010] [Indexed: 11/24/2022] Open
Abstract
Background High-throughput microarray experiments now permit researchers to screen thousands of genes simultaneously and determine the different expression levels of genes in normal or cancerous tissues. In this paper, we address the challenge of selecting a relevant and manageable subset of genes from a large microarray dataset. Currently, most gene selection methods focus on identifying a set of genes that can further improve classification accuracy. Few or none of these small sets of genes, however, are biologically relevant (i.e. supported by medical evidence). To deal with this critical issue, we propose two novel methods that can identify biologically relevant genes concerning cancers. Results In this paper, we propose two novel techniques, entitled random forest gene selection (RFGS) and support vector sampling technique (SVST). Compared with results from six other methods developed in this paper, we demonstrate experimentally that RFGS and SVST can identify more biologically relevant genes in patients with leukemia or prostate cancer. Among the top 25 genes selected using SVST method, 15 genes were biologically relevant genes in patients with leukemia and 13 genes were biologically relevant genes in patients with prostate cancer. Meanwhile, the RFGS method, while less effective than SVST, still identified an average of 9 biologically relevant genes in both leukemia and prostate cancers. In contrast to traditional statistical methods, which only identify less than 8 genes in patients with leukemia and less than 8 genes in patients with prostate cancer, our methods yield significantly better results. Conclusions Our proposed SVST and RFGS methods are novel approaches that can identify a greater number of biologically relevant genes. These methods have been successfully applied to both leukemia and prostate cancers. Research in the fields of biology and medicine should benefit from the identification of biologically relevant genes by confirming recent discoveries in cancer research or suggesting new avenues for exploration.
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Affiliation(s)
- Austin H Chen
- Department of Medical Informatics, Tzu Chi University, Hualien City, Hualien County, Taiwan.
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IL-18 Paradox in Pancreatic Carcinoma: Elevated Serum Levels of Free IL-18 are Correlated With Poor Survival. J Immunother 2009; 32:920-31. [DOI: 10.1097/cji.0b013e3181b29168] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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12
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Argiriadi MA, Xiang T, Wu C, Ghayur T, Borhani DW. Unusual water-mediated antigenic recognition of the proinflammatory cytokine interleukin-18. J Biol Chem 2009; 284:24478-89. [PMID: 19553661 DOI: 10.1074/jbc.m109.023887] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The unique cytokine interleukin-18 (IL-18) acts synergistically with IL-12 to regulate T-helper 1 and 2 lymphocytes and, as such, seems to underlie the pathogenesis of various autoimmune and allergic diseases. Several anti-IL-18 agents are in clinical development, including the recombinant human antibody ABT-325, which is entering trials for autoimmune diseases. Given competing cytokine/receptor and cytokine/receptor decoy interactions, understanding the structural basis for recognition is critical for effective development of anti-cytokine therapies. Here we report three crystal structures: the murine antibody 125-2H Fab fragment bound to human IL-18, at 1.5 A resolution; the 125-2H Fab (2.3 A); and the ABT-325 Fab (1.5 A). These structures, along with human/mouse IL-18 chimera binding data, allow us to make three key observations relevant to the biology and antigenic recognition of IL-18 and related cytokines. First, several IL-18 residues shift dramatically (> 10 A) upon binding 125-2H, compared with unbound IL-18 (Kato, Z., Jee, J., Shikano, H., Mishima, M., Ohki, I., Ohnishi, H., Li, A., Hashimoto, K., Matsukuma, E., Omoya, K., Yamamoto, Y., Yoneda, T., Hara, T., Kondo, N., and Shirakawa, M. (2003) Nat. Struct. Biol. 10, 966-971). IL-18 thus exhibits plasticity that may be common to its interactions with other receptors. Related cytokines may exhibit similar plasticity. Second, ABT-325 and 125-2H differ significantly in combining site character and architecture, thus explaining their ability to bind IL-18 simultaneously at distinct epitopes. These data allow us to define the likely ABT-325 epitope and thereby explain the distinct neutralizing mechanisms of both antibodies. Third, given the high 125-2H potency, 10 well ordered water molecules are trapped upon complex formation in a cavity between two IL-18 loops and all six 125-2H complementarity-determining regions. Thus, counterintuitively, tight and specific antibody binding may in some cases be water-mediated.
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Affiliation(s)
- Maria A Argiriadi
- Department of Biochemistry, Abbott Laboratories, Worcester, Massachusetts 01605, USA.
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Raices RM, Kannan Y, Sarkar A, Bellamkonda-Athmaram V, Wewers MD. A synergistic role for IL-1beta and TNFalpha in monocyte-derived IFNgamma inducing activity. Cytokine 2008; 44:234-41. [PMID: 18805021 DOI: 10.1016/j.cyto.2008.08.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Revised: 08/01/2008] [Accepted: 08/05/2008] [Indexed: 01/09/2023]
Abstract
Although much is known about classic IFNgamma inducers, little is known about the IFNgamma inducing capability of inflammasome-activated monocytes. In this study, supernatants from LPS/ATP-stimulated human monocytes were analyzed for their ability to induce IFNgamma production by KG-1 cells. Unexpectedly, monocyte-derived IFN inducing activity was detected, but it was completely inhibited by IL-1beta, not IL-18 blockade. Moreover, size-fractionation of the monocyte conditioned media dramatically reduced the IFNgamma inducing activity of IL-1beta, suggesting that IL-1beta requires a cofactor to induce IFNgamma production in KG-1 cells. Because TNFalpha is known to synergize with IL-1beta for various gene products, it was studied as the putative IL-1beta synergizing factor. Although recombinant TNFalpha (rTNFalpha) alone had no IFNgamma inducing activity, neutralization of TNFalpha in the monocyte conditioned media inhibited the IFNgamma inducing activity. Furthermore, rTNFalpha restored the IFNgamma inducing activity of the size-fractionated IL-1beta. Finally, rTNFalpha synergized with rIL-1beta, as well as with rIL-1alpha and rIL-18, for KG-1 IFNgamma release. These studies demonstrate a synergistic role between TNFalpha and IL-1 family members in the induction of IFNgamma production and give caution to interpretations of KG-1 functional assays designed to detect functional IL-18.
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Affiliation(s)
- Raquel M Raices
- The Ohio State University, Davis Heart and Lung Research Institute, Pulmonary, Allergy, Clinical Care and Sleep Medicine Division, 473 West 12th Avenue, Room 435, Columbus, OH 43210, USA
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Adalsteinsson V, Parajuli O, Kepics S, Gupta A, Reeves WB, Hahm JI. Ultrasensitive detection of cytokines enabled by nanoscale ZnO arrays. Anal Chem 2008; 80:6594-601. [PMID: 18681455 DOI: 10.1021/ac800747q] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Early detection of disease markers can provide higher diagnostic power and improve disease prognosis. We demonstrate the use of zinc oxide nanorod (ZnO NR) arrays in a straightforward, reliable, and ultrasensitive detection of the cytokines interleukin-18 and tumor necrosis factor-alpha. Specifically, we exploit the fluorescence-enhancing properties of ZnO NR platforms in cytokine assays involving both a pure buffer and urine. The detection sensitivity achieved using this ZnO NR method is in the subfemtogram per milliliter level, which is 3-4 orders of magnitude more sensitive than conventional assay detection limits. This unparalleled detection sensitivity is achieved without the need for indirect enzyme reactions or specialized instrumentation. We highlight various advantages of using ZnO NR arrays in the ultrasensitive profiling of cytokine levels. Key advantages include robustness of NR arrays, simple and direct assay schemes, high-throughput and multiplexing capabilities, and the ability to correlate directly measured signals to cytokine levels. In conjunction with the extremely high sensitivity demonstrated in this work, our ZnO NR array-based approach may be highly beneficial in early detection of many cytokine-implicated diseases.
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Affiliation(s)
- Viktor Adalsteinsson
- Department of Chemical Engineering, The Pennsylvania State University, 160 Fenske Laboratory, University Park, Pennsylvania 16802, USA
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Yoshimoto T, Tsutsui H, Okamura H, Nakanishi K. Measurement of human and mouse interleukin 18. CURRENT PROTOCOLS IN IMMUNOLOGY 2008; Chapter 6:Unit 6.26. [PMID: 18432815 DOI: 10.1002/0471142735.im0626s44] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
IL-18, originally designated as interferon-gamma (IFN-gamma)-inducing factor (IGIF), is a pleiotropic cytokine secreted by activated macrophages and Kupffer cells. The major activity associated with this cytokine is induction of IFN-gamma production from T cells, B cells, and NK cells, especially in collaboration with IL-12. IL-18 is synthesized without a signal peptide and must be enzymatically cleaved to become active. Therefore, it is important to determine whether the produced IL-18 is an active or precursor form. This unit describes functional assays for measurement of bioactive human and mouse IL-18 and ELISAs for measurement of murine and human IL-18 proteins. The functional assays are based on the induction of IFN-gamma production by IL-18. The ELISA measures the concentration of human or mouse IL-18. Using a combination of monoclonal antibodies against human or mouse IL-18, the proform and/or mature form of IL-18 can be detected by ELISA.
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Leslie JA, Meldrum KK. The role of interleukin-18 in renal injury. J Surg Res 2007; 145:170-5. [PMID: 17658553 DOI: 10.1016/j.jss.2007.03.037] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2006] [Revised: 03/19/2007] [Accepted: 03/20/2007] [Indexed: 11/20/2022]
Abstract
Interleukin (IL)-18 is a relatively new pro-inflammatory cytokine, formerly known as interferon-gamma-inducing factor, which induces interferon-gamma production in T cells and natural killer cells. It is synthesized as a biologically inactive precursor, which requires cleavage into an active molecule by an intracellular cysteine protease similar to IL-1beta. This review examines the pro-inflammatory role of IL-18 in various types of renal injury (i.e., endotoxemia, cisplatin toxicity, allograft rejection, and ischemia-reperfusion injury) and explores the integral role of IL-12 in IL-18 function and activity.
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Affiliation(s)
- Jeffrey A Leslie
- Department of Urology, James Whitcomb Riley Hospital for Children, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA
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Cumiskey D, Pickering M, O'Connor JJ. Interleukin-18 mediated inhibition of LTP in the rat dentate gyrus is attenuated in the presence of mGluR antagonists. Neurosci Lett 2006; 412:206-10. [PMID: 17123727 DOI: 10.1016/j.neulet.2006.11.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2006] [Revised: 10/27/2006] [Accepted: 11/03/2006] [Indexed: 11/18/2022]
Abstract
Pro-inflammatory cytokines are known to be elevated in several neuropathological states that are associated with learning and memory impairments. We have previously demonstrated the inhibition of long-term potentiation (LTP), a recognised model for memory, in the dentate gyrus region of the rat hippocampus, by interleukin-18. We have also previously shown that the inhibitory effect of TNF-alpha on LTP can be attenuated by inhibitors of metabotropic glutamate receptors (mGluRs). We therefore went on to investigate the effects of the mGluR antagonists MPEP and MTPG on the effect of IL-18 on LTP in the rat dentate gyrus in vitro. Recordings of field excitatory post-synaptic potentials (EPSPs) were made from the medial perforant path of rat hippocampal slices. IL-18 (100 ng/ml) applied for 20 min before-HFS had no significant effect on baseline EPSPs but significantly impaired LTP (IL-18 LTP 116+/-9%, versus control LTP 163+/-6% 1h post-tetanus, P<0.001, n=5). Perfusion of the mGluR5 specific antagonist MPEP (5 microM) for 40 min prior to application of IL-18 had no significant effect on baseline EPSPs but significantly attenuated the inhibitory effect of IL-18 on LTP at 30 min but not 1h (177+/-2% and 138+/-8%, respectively, compared to controls; n=5). Perfusion of the group II mGluR antagonist MTPG (50 microM) for 40 min prior to application of IL-18 had no significant effect on baseline EPSPs but was found to significantly reverse the inhibitory effect of IL-18 on LTP at 1h (164+/-6% compared to IL-18 alone, n=5). This study provides novel evidence of the involvement of mGluRs in the IL-18 mediated inhibition of LTP.
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Affiliation(s)
- Derval Cumiskey
- UCD School of Biomolecular and Biomedical Science, UCD Conway Institute of Biomolecular & Biomedical Research, Belfield, Dublin 4, Ireland
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18
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Hamasaki T, Hashiguchi S, Ito Y, Kato Z, Nakanishi K, Nakashima T, Sugimura K. Human Anti–Human IL-18 Antibody Recognizing the IL-18–Binding Site 3 with IL-18 Signaling Blocking Activity. ACTA ACUST UNITED AC 2005; 138:433-42. [PMID: 16272137 DOI: 10.1093/jb/mvi148] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
IL-18 is an important regulator in both innate and acquired immune responses. The aberrant expression of IL-18 is associated with severe inflammatory conditions, such as autoimmune diseases and allergies. Thus, human antibodies with inhibitory activity on IL-18 signaling may be useful for therapeutic applications. We report here the first establishment of an antagonistic anti-IL-18 complete human antibody, h18-108, employing a human single chain antibody (scFv)-displaying phage library. The h18-108 scFv inhibited the IFN-gamma production of a human myelomonocytic cell line, KG-1. Flow cytometry analysis showed that h18-108 blocked the binding of IL-18 to KG-1 cells. Epitope mapping analysis using two kinds of random peptide-displaying phage libraries and an IL-18 alanine mutant (D98A) demonstrated that the h18-108 scFv binds to the site 3 of IL-18, which is suggested to be an association site with the IL-18 receptor beta. The complete human Fab and IgG forms of h18-108 have been successfully constructed to attain increases in both binding affinity and inhibitory activity.
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Affiliation(s)
- Takayuki Hamasaki
- Department of Bioengineering, Faculty of Engineering, Kagoshima University, Korimoto 1-21-40, Kagoshima 890-0065, Japan
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19
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Muneta Y, Yoshihara K, Minagawa Y, Nagata R, Yasuyuki M, Yamaguchi T, Takehara K. Bovine IL-18 ELISA: detection of IL-18 in sera of pregnant cow and newborn calf, and in colostrum. J Immunoassay Immunochem 2005; 26:203-13. [PMID: 16011146 DOI: 10.1081/ias-200062487] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
In this study, we examined the concentration of bovine IL-18 in the sera of pregnant cows, their fetuses and newborn calves, and in colostrum in order to examine the role of IL-18 in bovine pregnancy and the neonatal period. A sandwich-ELISA to quantify bovine IL-18 was established using anti-porcine IL-18 monoclonal antibodies, which cross-reacted with bovine IL-18, and used it to measure the concentration of bovine IL-18 in the sera of pregnant cows, their fetuses and newborn calves, and in colostrum. Significant levels of IL-18 were detected in the sera of pregnant cows, but not in the sera obtained from the corresponding fetuses, umbilical arteries and veins. After birth, IL-18 levels in the sera of 1-day and 1-week old calves were low, and significantly increased in the sera of 1-month and 4-month old calves. IL-18 was also detected in colostrum, with the concentration of IL-18 in the first colostrum produced after delivery being the highest, and then decreasing depending on the number of milkings. Furthermore, the serum IL-18 concentration of newborn calves was increased after the oral administration of colostrum. These results suggest that IL-18 during bovine pregnancy and in the newborn period may play important roles in the maintenance of pregnancy and in the maturation of neonatal immunity.
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Affiliation(s)
- Yoshihiro Muneta
- National Institute of Animal Health, 3-1-5, Kannondai, Tsukuba, Ibaraki 305-0856, Japan.
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20
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Oztas MO, Onder M, Gurer MA, Bukan N, Sancak B. Serum interleukin 18 and tumour necrosis factor-alpha levels are increased in Behcet's disease. Clin Exp Dermatol 2005; 30:61-3. [PMID: 15663506 DOI: 10.1111/j.1365-2230.2004.01684.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Inflammation in Behcet's disease is thought to be mediated by cytokines derived from T-helper type 1 (Th1) lymphocytes. In this study, we tried to determine serum interleukin (IL)-18 and tumour necrosis factor (TNF)-alpha levels of patients with Behcet's disease. Twenty-seven patients with active Behcet's disease, and 20 healthy control subjects were included in this study. Differences between mean serum IL-18 and TNF-alpha level of patients with Behcet's disease were significantly increased when compared with the control group. A significant correlation was found between serum IL-18 and TNF-alpha levels of Behcet patients (rs = 0.627, P < 0.0001). IL-18 and TNF-alpha levels may be related to disease pathogenesis. Increased levels of IL-18 also support Th1 predominance in Behcet's disease.
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Affiliation(s)
- M O Oztas
- Department of Dermatology, Gazi University Faculty of Medicine, Besevler, Ankara, Turkey.
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21
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Rooney T, Murphy E, Benito M, Roux-Lombard P, FitzGerald O, Dayer JM, Bresnihan B. Synovial tissue interleukin-18 expression and the response to treatment in patients with inflammatory arthritis. Ann Rheum Dis 2004; 63:1393-8. [PMID: 15479888 PMCID: PMC1754818 DOI: 10.1136/ard.2003.016428] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
OBJECTIVE To measure synovial tissue interleukin-18 (IL-18) expression in patients with inflammatory arthritis, and to identify associations with serum levels, disease activity, and response to treatment. METHODS Synovial tissue biopsies and serum samples were obtained from patients with early, active, rheumatoid arthritis (RA) (n = 12), undifferentiated seronegative arthritis (SnA) (n = 9), psoriatic arthritis (PsA) (n = 5), and reactive arthritis (ReA) (n = 2) before and one year after introduction of disease modifying antirheumatic drug (DMARD) treatment. Osteoarthritis (OA) tissues were compared. Tissue IL-18 expression was determined after immunohistochemical staining using a semiquantitative scale. Serum IL-18 was measured by enzyme linked immunosorbent assay. RESULTS Before treatment was started, tissue IL-18 expression was increased in each diagnostic group compared with OA (p<0.05). Tissue IL-18 expression was correlated with serum C reactive protein levels (r = 0.53, p = 0.003) but not with serum IL-18. After DMARD treatment, 12 patients (five RA, four SnA, three PsA) were re-evaluated. Decreases in tissue IL-18 expression were observed in eight, although the trend did not reach significance (p = 0.068). Changes in tissue IL-18 expression were correlated with changes in serum IL-18 (r = 0.62, p = 0.041) and C reactive protein (r = 0.72, p = 0.009). CONCLUSIONS Synovial tissue IL-18 expression was correlated with disease activity in inflammatory arthritis. After treatment, tissue levels changed in parallel with changes in serum IL-18 and with changes in the acute phase response. These observations support a role for IL-18 in the pathophysiology of inflammatory arthritis.
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Affiliation(s)
- T Rooney
- Department of Rheumatology, St Vincent's University Hospital, Elm Park, Dublin 4, Republic of Ireland.
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22
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Coskun U, Gunel N, Sancak B, Onuk E, Bayram M, Cihan A. Effect of tamoxifen on serum IL-18, vascular endothelial growth factor and nitric oxide activities in breast carcinoma patients. Clin Exp Immunol 2004; 137:546-51. [PMID: 15320904 PMCID: PMC1809129 DOI: 10.1111/j.1365-2249.2004.02579.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is a multi-functional cytokine that has been suggested to be a major angiogenic factor in breast cancer. Nitric oxide (NO) is a potent biological molecule that participates in the multi-step process of carcinogenesis. Interleukin (IL)-18 has been shown to have potent anti-tumour effects. In this study, we investigated the effect of tamoxifen therapy on serum VEGF, NO and IL-18 activity in breast cancer patients. Serum levels of VEGF, nitrate + nitrite and IL-18 were measured in 34 postmenopausal breast cancer patients before and 3 months after the tamoxifen therapy. Both serum VEGF and IL-18 levels decreased after tamoxifen therapy (P = 0.051, P < 0.05, respectively). Serum VEGF levels increased in patients with endometrial thickness, while patients without endometrial thickness had a significant reduction in serum VEGF levels after therapy (P < 0.05). Serum nitrate + nitrite levels increased after the therapy, but this was not statistically significant (P > 0.05). A decrease in serum VEGF levels with tamoxifen therapy may be a reflection of reduced angiogenic activity in patients without endometrial thickness. The negative effect of tamoxifen therapy on IL-18, which is known to have a potent antitumour activity, may be related to the decreased tumour growth by induction of NO and reduction of VEGF activity as a feedback mechanism.
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Affiliation(s)
- U Coskun
- Department of Medical Oncology, Gazi University Medical School, Ankara, Turkey.
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23
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Induction of comprehensible models for gene expression datasets by subgroup discovery methodology. J Biomed Inform 2004; 37:269-84. [DOI: 10.1016/j.jbi.2004.07.007] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2004] [Indexed: 11/23/2022]
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24
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Kojima S, Nagamine Y, Hayano M, Looareesuwan S, Nakanishi K. A potential role of interleukin 18 in severe falciparum malaria. Acta Trop 2004; 89:279-84. [PMID: 14744554 DOI: 10.1016/j.actatropica.2003.10.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Interleukin-18 (IL-18) is a potent proinflammatory cytokine that induces interferon-gamma (IFN-gamma) production from Th1 cells, NK cells and activated macrophages, particularly in the presence of IL-12. However, it is also shown that without help from IL-12, IL-18 is capable of inducing IL-4 and IL-13 production in T cells, NK cells, mast cells and basophils, and that administration of IL-18 in conjunction with an allergen increases serum IgE levels. In order to clarify the role of IL-18 in disease severity of falciparum malaria, we have examined serum levels of IL-18, IFN-gamma, and IgE for 96 patients with falciparum malaria [Trans. R. Soc. Trop. Med. Hyg. 97, 236-241]. Results suggested that IL-18 plays a key role in inducing severe malaria through a pathway of elevating IFN-gamma, rather than its IgE inducing activity. Based on these results, the role of IL-18 in severe falciparum malaria will be discussed in this review.
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Affiliation(s)
- Somei Kojima
- Department of Parasitology, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
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25
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Arici A, Matalliotakis I, Goumenou A, Koumantakis G, Vassiliadis S, Mahutte NG. Altered expression of interleukin-18 in the peritoneal fluid of women with endometriosis. Fertil Steril 2003; 80:889-94. [PMID: 14556808 DOI: 10.1016/s0015-0282(03)01122-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Peritoneal fluid (PF) inflammatory factors may participate in the pathogenesis of endometriosis. The aim of this study was to investigate PF interleukin (IL)-18 levels in women with and without endometriosis. DESIGN Controlled clinical study. SETTING Women undergoing laparoscopy at a university hospital. PATIENT(S) Fifty women with previously untreated endometriosis, 8 women on GnRH agonists for endometriosis, and 18 control women with normal pelvic anatomy who were undergoing tubal ligation. INTERVENTION(S) Peritoneal fluid IL-18 levels as measured by ELISA. MAIN OUTCOME MEASURE(S) Peritoneal fluid IL-18 levels. RESULT(S) Peritoneal fluid IL-18 levels were significantly higher in women with previously untreated endometriosis (mean +/- SEM, 91.1 +/- 6.5 pg/mL) than in control women (59.4 +/- 2.0 pg/mL). Interestingly, women with superficial (100.0 +/- 10.2 pg/mL) and deep peritoneal implants (94.0 +/- 10.8 pg/mL) had significantly higher PF IL-18 levels than did women with endometriomas (57.8 +/- 1.8 pg/mL). Similarly, women with stage I-II endometriosis (97.3 +/- 8.0 pg/mL), but not women with stage III-IV endometriosis (74.9 +/- 9.9 pg/mL), had significantly higher PF IL-18 levels than did control women. Peritoneal fluid IL-18 levels were significantly higher in the luteal phase than in the follicular phase but did not discriminate between women with pelvic pain or infertility. CONCLUSION(S) Peritoneal fluid IL-18 is elevated in women with peritoneal, minimal- to mild-stage endometriosis.
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Affiliation(s)
- Aydin Arici
- Department of Obstetrics and Gynecology, Yale University School of Medicine, New Haven, Connecticut 06520-8063, USA.
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26
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Zhang B, Cao ZY, Wu KF, Lin YM. Expression and functional reconstitution of IL-18 receptor in K562 leukemia cells. Leuk Res 2003; 27:971-2. [PMID: 12860020 DOI: 10.1016/s0145-2126(03)00048-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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27
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Zhang B, Ma XT, Zheng GG, Li G, Rao Q, Wu KF. Expression of IL-18 and its receptor in human leukemia cells. Leuk Res 2003; 27:813-22. [PMID: 12804640 DOI: 10.1016/s0145-2126(03)00005-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The importance of IL-18, although clearly established in solid tumors, has not been fully elucidated in human hematopoietic neoplasms. Here we examined the mRNA and protein for IL-18 in eight human hematopoietic cell lines representing different lineages and neoplasms including leukemia, lymphoma and others. Our results revealed that IL-18 mRNA was expressed in these cells and that the corresponding protein was found in the cytoplasm. Seven of eight cell lines were also found to express two subunits of the IL-18 receptor (IL-18R) at varied levels. Furthermore, 29 out of 51 leukemia patients tested were observed to express IL-18R with 18/29 (62%) co-expression of both receptor and ligand. By blocking the IL-18 loop using specific antisense oligodeoxynucleotide (ASON) for IL-18 mRNA or anti-human IL-18R monoclonal antibody (McAbR), we were not able to demonstrate a marked inhibition on the most leukemic cell lines growth. Moreover, the potential proliferation in vitro of primary AML cells co-expressing IL-18 and its receptor was not significantly enhanced by recombinant human IL-18, suggesting that IL-18 is not apparently implicated in the proliferation of the leukemia cells via an autocrine loop. Additionally, we also found the effective modulating effect of M-CSF, IFN-alpha and TNF-alpha on IL-18R expression, implying an important in vivo effect of cytokines on IL-18-induced reaction. Moreover, the modulation of IL-18R expression was possibly irrelevant to IFN-gamma secretion induced by these cytokines.
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Affiliation(s)
- Bin Zhang
- National Laboratory of Experimental Hematology, Institute of Hematology and Blood Disease Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, PR China
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28
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Manigold T, Böcker U, Chen J, Gundt J, Traber P, Singer MV, Rossol S. Hepatitis B core antigen is a potent inductor of interleukin-18 in peripheral blood mononuclear cells of healthy controls and patients with hepatitis B infection. J Med Virol 2003; 71:31-40. [PMID: 12858406 DOI: 10.1002/jmv.10445] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Clearance of hepatitis B virus infection (HBV) infection implies a polyclonal vigorous T-helper 1 (Th1) and cytotoxic T-lymphocyte (CTL) response. Interleukin-18 (IL-18), a monokine that shares functional abilities with IL-12, is a potent inductor of interferon-gamma (IFN-gamma) by Th1 and natural killer (NK) cells. However, the role and regulation in HBV infection of IFN-gamma have not been defined. This study therefore sought to determine hepatitis B core antigen (HBcAg)-mediated regulation of IL-18 production in peripheral blood mononuclear cells (PBMCs) from healthy controls (HC) and patients with chronic hepatitis B (CHB) or acute hepatitis B (AHB); 31 HC, 27 patients with CHB and 8 patients with AHB infection were included in the study. HBcAg-mediated induction of IL-18 was determined by quantitative reverse transcription-polymerase chain reaction (RT-PCR) and specific enzyme-linked immunosorbent assay (ELISA). HBcAg induced IL-18 gene transcription and dose-dependent secretion of mature IL-18 protein in HC, CHB, and AHB. HBcAg-dependent IL-18 levels were abrogated by inhibition of Caspase-1, but not by blockade of CD40-CD154 interaction. Serum levels of IFN-gamma correlated inversely with viremia in patients with CHB (rho = - 0.54, P < 0.05), but not with serum levels of IL-12 or IL-18. Interestingly, in PBMCs of HBeAg-negative patients, HBcAg induced significantly higher amounts of IL-18 than in those of HBeAg-positive patients. A variant, lacking the histone-like arginine-rich domain, did not induce IL-18 in either HC or CHB in vitro. Taken together, these results indicate that HBcAg induces IL-18 secretion by induction of Caspase-1. Differential regulation in HBeAg-negative and positive patients suggests an important role of IL-18 in CHB infection.
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Affiliation(s)
- Tobias Manigold
- Department of Medicine II, Gastroenterology/Hepatology/Infectious Diseases, University Hospital Mannheim, Mannheim, Germany.
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29
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Hentze H, Lin XY, Choi MSK, Porter AG. Critical role for cathepsin B in mediating caspase-1-dependent interleukin-18 maturation and caspase-1-independent necrosis triggered by the microbial toxin nigericin. Cell Death Differ 2003; 10:956-68. [PMID: 12934070 DOI: 10.1038/sj.cdd.4401264] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The potassium ionophore nigericin induces cell death and promotes the maturation and release of IL-1beta in lipopolysaccharide (LPS)-primed monocytes and macrophages, the latter depending on caspase-1 activation by an unknown mechanism. Here, we investigate the pathway that triggers cell death and activates caspase-1. We show that without LPS priming, nigericin alone triggered caspase-1 activation and IL-18 generation in THP-1 monocytic cells. Simultaneously, nigericin induced caspase-1-independent necrotic cell death, which was blocked by the cathepsin B inhibitor CA-074-Me and other cathepsin inhibitors. Cathepsin B activation after nigericin treatment was determined biochemically and corroborated by rapid lysosomal leakage and translocation of cathepsin B to the cytoplasm. IL-18 maturation was prevented by both caspase-1 and cathepsin B inhibitors in THP-1 cells, primary mouse macrophages and human blood monocytes. Moreover, IL-18 generation was reduced in THP-1 cells stably transformed either with cystatin A (an endogenous cathepsin inhibitor) or antisense cathepsin B cDNA. Collectively, our study establishes a critical role for cathepsin B in nigericin-induced caspase-1-dependent IL-18 maturation and caspase-1-independent necrosis.
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Affiliation(s)
- H Hentze
- Institute of Molecular and Cell Biology, Singapore, Republic of Singapore
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30
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Kaizu M, Ami Y, Nakasone T, Sasaki Y, Izumi Y, Sato H, Takahashi E, Sakai K, Shinohara K, Nakanishi K, Honda M. Higher levels of IL-18 circulate during primary infection of monkeys with a pathogenic SHIV than with a nonpathogenic SHIV. Virology 2003; 313:8-12. [PMID: 12951016 DOI: 10.1016/s0042-6822(03)00434-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We have monitored kinetics of peripheral blood Interleukin (IL)-18 level, viral RNA load, and CD4(+) T cell counts in cynomolgus and rhesus macaques following infections of various simian/human immunodeficiency viruses (SHIVs) causing differential pathogenicity. Infections of cynomolgus and rhesus macaques with pathogenic SHIVs-C2/1 and -89.6PD, respectively, induced high levels of plasma IL-18 (0.1-1 ng/ml) and enhanced apoptosis of peripheral blood T cells during primary viremia, along with a rapid decline of CD4(+) T cells and a high level of set point viral load after primary viremia (six of six cases). In contrast, infections of cynomolgus macaques with nonpathogenic SHIVs-TH09V3 and -MD14 did not cause such IL-18 elevation, showing no decline of CD4(+) T cells and no or low viral set point level following primary viremia (three of three cases). Thus, the elevation of circulating IL-18 level during primary viral infection can be a good indicator of an active pathogenic viral infection. However, the role of increased IL-18 remains to be elucidated and needs further investigation.
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Affiliation(s)
- Masahiko Kaizu
- AIDS Research Center, National Institute of Infectious Diseases, Shinjuku, Tokyo 162-8640, Japan
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31
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Günel N, Coskun U, Sancak B, Hasdemir O, Sare M, Bayram O, Celenkoglu G, Ozkan S. Prognostic value of serum IL-18 and nitric oxide activity in breast cancer patients at operable stage. Am J Clin Oncol 2003; 26:416-21. [PMID: 12902898 DOI: 10.1097/01.coc.0000027416.15170.53] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Interleukin-18 (IL-18) is a multifunctional cytokine that was previously termed interferon-gamma-inducing factor. It has been suggested that serum IL-18 level may be used as a prognostic factor in some cancer types. Nitric oxide is a potent biologic molecule involved in the pathogenesis of cancer. In this study, we measured serum IL-18 and nitrate + nitrite levels in 56 patients with nonmetastatic breast cancer and 14 control subjects. Serum IL-18* and nitrate + nitrite** levels were significantly higher in patients with breast cancer when compared to the control subjects (*p < 0.05, **p < 0.001). Serum IL-18 levels were significantly higher in patients whose tumor size was greater than or equal to 5 cm when compared to patients whose tumor size was less than or equal to 2 cm (p < 0.05). Patients who were axillary lymph node negative (ALN) had lower serum IL-18 levels when compared to patients with positive ALN (p < 0.001). Serum IL-18 levels were significantly higher in patients with stage IIB or IIIA when compared to patients with stage I or IIA (p < 0.05). There was no significant difference in serum nitrate + nitrite levels in terms of age, tumor stage, estrogen receptor, and menopausal and ALN status (p > 0.05). In conclusion, serum IL-18 level may be a useful marker to predict prognosis of patients with breast cancer in complete remission after surgery. Long-term follow-up is required to clarify this hypothesis.
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Affiliation(s)
- Nazan Günel
- Department of Medical Oncology, Gazi University Medical School, Ankara, Turkey
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32
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Wu C, Sakorafas P, Miller R, McCarthy D, Scesney S, Dixon R, Ghayur T. IL-18 receptor beta-induced changes in the presentation of IL-18 binding sites affect ligand binding and signal transduction. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:5571-7. [PMID: 12759435 DOI: 10.4049/jimmunol.170.11.5571] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
IL-18 is a pleiotropic proinflammatory cytokine that is involved in induction of inflammatory mediators, regulation of the cytotoxic activity of NK cells and T cells, and differentiation and activation of both Th1 and Th2 cells. IL-18 signals through its specific cell surface receptor IL-18R, which comprises two subunits: IL-18R alpha and IL-18R beta. IL-18R alpha alone has a weak affinity for IL-18 binding, while the IL-18R alpha/beta complex has a high affinity. By using several anti-IL-18 mAbs and IL-18 binding protein, we have examined whether these site-specific inhibitors could block the binding of IL-18 to IL-18R alpha and to the IL-18R alpha/beta complex. Here we show that IL-18 binding to IL-18R alpha was inhibited by a neutralizing mAb, 125-2H, while binding of IL-18 to the alpha/beta receptor complex was not. This suggests that IL-18R beta-induced conformational changes may occur in IL-18R alpha upon dimerization, leading to changes in the presentation of IL-18 binding sites. Epitope mapping of 125-2H using human-mouse IL-18 chimeras identified a region in IL-18 that was required for 125-2H recognition. This region, as examined by IL-18R binding and functional analysis, appeared to be critical for triggering signal transduction through the heterodimeric receptor.
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MESH Headings
- Animals
- Antibodies, Blocking/chemistry
- Antibodies, Blocking/metabolism
- Antibodies, Blocking/pharmacology
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/metabolism
- Antibodies, Monoclonal/pharmacology
- Antigen Presentation/genetics
- Binding Sites/genetics
- Binding Sites/immunology
- Binding Sites, Antibody/genetics
- Dimerization
- Epitope Mapping
- Humans
- Interleukin-18/antagonists & inhibitors
- Interleukin-18/biosynthesis
- Interleukin-18/immunology
- Interleukin-18/metabolism
- Interleukin-18 Receptor alpha Subunit
- Ligands
- Mice
- Peptide Fragments/chemistry
- Peptide Fragments/immunology
- Peptide Fragments/metabolism
- Protein Binding/immunology
- Protein Conformation
- Protein Subunits/antagonists & inhibitors
- Protein Subunits/biosynthesis
- Protein Subunits/metabolism
- Receptors, Interleukin/antagonists & inhibitors
- Receptors, Interleukin/metabolism
- Receptors, Interleukin/physiology
- Receptors, Interleukin-18
- Recombinant Fusion Proteins/chemical synthesis
- Recombinant Fusion Proteins/metabolism
- Signal Transduction/immunology
- Tumor Cells, Cultured
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Affiliation(s)
- Chengbin Wu
- Abbott Bioresearch Center, Worcester, MA 01605, USA.
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33
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Maiti PK, Im SH, Souroujon MC, Fuchs S. A monoclonal antibody specific for rat IL-18BP and its application in determining serum IL-18BP. Immunol Lett 2003; 85:65-70. [PMID: 12505199 DOI: 10.1016/s0165-2478(02)00213-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
IL-18 binding protein (IL-18BP) is a soluble inhibitory receptor for IL-18, a proinflammatory cytokine that plays a major role in IL-12-driven Th1 cell differentiation. IL-18BP is presumed to play a vital regulatory function in IL-18-mediated immune responses, although its precise role in immunomodulation in various diseases is not well understood. In the present study, we have generated and characterized a mouse monoclonal antibody (2A6H11), specific for rat IL-18BP. Its binding epitope is within amino acids 29-60 on IL-18BP and it does not interfere with the function of IL-18BP. Using this monoclonal antibody, we have developed an ELISA for determining IL-18BP levels. We observed elevated levels of IL-18BP in sera of rats with experimental autoimmune myasthenia gravis (EAMG), in comparison with the levels in healthy rats. Thus, this monoclonal antibody can serve as a valuable tool to elucidate the role of IL-18BP in EAMG and in other rat models for autoimmune diseases.
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Affiliation(s)
- Prasanta K Maiti
- Department of Immunology, Weizmann Institute of Science, 76100, Rehovot, Israel
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34
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Okazawa A, Kanai T, Watanabe M, Yamazaki M, Inoue N, Ikeda M, Kurimoto M, Ishii H, Hibi T. Th1-mediated intestinal inflammation in Crohn's disease may be induced by activation of lamina propria lymphocytes through synergistic stimulation of interleukin-12 and interleukin-18 without T cell receptor engagement. Am J Gastroenterol 2002; 97:3108-17. [PMID: 12492197 DOI: 10.1111/j.1572-0241.2002.07107.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The development of T helper type 1 (Th1) CD4+ T cells in the intestinal mucosa is driven by interleukin (IL)-12 produced from activated macrophages and IL-18 produced from activated macrophages and epithelial cells. Each of these two cytokines is important for the mucosal response during intestinal inflammation, but their synergistic effect is not fully understood. To characterize the synergistic effect of IL-12 and IL-18 with respect to human intestinal inflammation, we assessed the effect of IL-12 and IL-18 on lamina propria lymphocytes from normal control subjects (LPL-NL) and patients with Crohn's disease (LPL-CD). METHODS Expression of IL-12 receptor (IL-12R) beta1, beta2, and IL-18Ralpha in LPLs was analyzed by flow cytometry. The functional activity of IL- 12 and IL-18 was assessed by the effect of recombinant IL-12 and recombinant IL-18 on interferon-gamma production, the proliferative response, and the induction of IL-2R, IL-12R, and IL-18R of LPLs. RESULTS IL-12Rbeta2 expression was significantly greater in LPL-CD compared with LPL-NL. LPL-NL demonstrated a proliferative response and a significant increase in interferon-gamma production and IL-2Ralpha expression when exposed to both IL- 12 and IL- 18, but neither IL- 12 nor IL-18 were able to induce this response on their own. However, IL-12 and IL-18 produced this response in LPL-CD when administered alone. Moreover, a more pronounced synergistic effect of IL-12 and IL-18 was observed in LPL-CD. The response normally observed after administration of IL-12 and IL-18 was significantly inhibited by anti-IL-2 and anti-IL-2Ralpha monoclonal antibody. Furthermore, IL-12 was observed to upregulate IL-18Ralpha expression in LPL-CD. CONCLUSIONS These findings suggest that a combination of IL-12 and IL-18 in the absence of T cell receptor engagement may serve as a potent regulatory factor for LPL and contribute to the maintenance and enhancement of chronic inflammation in CD.
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Affiliation(s)
- Akira Okazawa
- Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
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35
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Giavedoni LD, Velasquillo MC, Parodi LM, Hubbard GB, Hodara VL. Expression of IL-18 by SIV does not modify the outcome of the antiviral immune response. Virology 2002; 303:327-37. [PMID: 12490394 DOI: 10.1006/viro.2002.1647] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Interleukin 18 (IL-18) is a proinflammatory cytokine expressed by several cell types, including activated dendritic cells and macrophages, that acts in synergy with IL-12 as an important amplifying factor for IFN-gamma production and Th1 development. To study the immunological and virological effects of IL-18 expression in the context of a lentiviral infection, we inoculated rhesus macaques with a high dose of replication-competent simian immunodeficiency virus (SIV) vectors carrying the rhesus IL-18 gene in the sense (SIV(IL-18)) or antisense (SIV(FIGI)) orientation. Both vectors behaved as attenuated viruses, resulting in low viral loads, induction of low and transient levels of inflammatory cytokines, no CD4(+) T cell depletion, and mild activation of T lymphocytes. Although IL-18-expressing virus could be isolated from some SIV(IL18)-infected macaques for 12 weeks postinfection, the anti-SIV humoral and cellular immune responses of macaques inoculated with SIV(IL18) and SIV(FIGI) were similar to each other, with the exception of an early IFN-gamma response in animals infected with SIV(IL18). In summary, expression of IL-18 during the acute phase of SIV infection does not increase viral replication or influence the outcome of the antiviral immune response.
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Affiliation(s)
- Luis D Giavedoni
- Department of Virology and Immunology, Southwest Foundation for Biomedical Research, San Antonio, Texas 78245-0549, USA.
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36
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Pirhonen J, Matikainen S, Julkunen I. Regulation of virus-induced IL-12 and IL-23 expression in human macrophages. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:5673-8. [PMID: 12421946 DOI: 10.4049/jimmunol.169.10.5673] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
IL-23 is a novel cytokine that promotes the proliferation of naive and memory T cells and stimulates their IFN-gamma production. Besides functional similarities, IL-23 bears structural resemblance to IL-12. Biologically active IL-23 is a heterodimer whose p40 subunit is identical to IL-12p40 while its p19 subunit is distantly related to IL-12p35. In the present study we demonstrate that human monocyte-derived macrophages are able to produce IL-23 in response to virus infection. Sendai virus stimulates the expression of p19 and p40 mRNAs in macrophages. Furthermore, it enhances p35 mRNA expression and the production of IL-12. Influenza A virus, in contrast, fails to stimulate IL-12 or IL-23 expression in macrophages. IL-12 and IL-23 contribute to the IFN-gamma-inducing activity that cell culture supernatant from Sendai virus-infected macrophages show in NK-92 cells. The induction of IFN-gamma production occurs in concert with IFN-alphabeta and IL-18, which are also secreted from the virus-infected cells. The IFN-gamma-inducing activity is inhibited by IL-4, which down-regulates the transcription of p19 and p40 genes and the secretion of IFN-alphabeta, IL-12, and IL-18. IFN-gamma, in contrast, up-regulates the p19 and p40 mRNA expression in Sendai virus infection. Thus, IL-4 and IFN-gamma serve as opposing factors in the regulation of IFN-gamma-inducing cytokines, including IL-23, in macrophages.
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Affiliation(s)
- Jaana Pirhonen
- Department of Microbiology, National Public Health Institute, Mannerheimintie 166, FIN-00300 Helsinki, Finland.
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37
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Zhang B, Wang Y, Zheng GG, Ma XT, Li G, Zhang FK, Wu KF. Clinical significance of IL-18 gene over-expression in AML. Leuk Res 2002; 26:887-92. [PMID: 12163048 DOI: 10.1016/s0145-2126(02)00025-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Little is known about the clinical significance of interleukin (IL)-18, a novel immunoregulatory cytokine, in acute myeloid leukemia (AML). Using reverse transcriptase polymerase chain reaction (RT-PCR) analysis, levels of IL-18 mRNA were assessed in bone marrow mononuclear cells (BMMC) from 47 adult patients with de novo or CR AML in order to explore the clinical significance of IL-18. The relationship between expression levels and the established prognostic factors such as age, cytogenetic aberrations, CD34 expression and FAB subtypes was investigated. Either disease status, age or CD34 expression were found to significantly correlate with the expression of IL-18. With respect to FAB cytotypes, expression of IL-18 gene in M4/M5 (n=15) was statistically higher than that in other subtypes (n=32, P<0.001). Moreover, a significant difference in IL-18 gene expression was obtained between the high risk group and the intermediate risk group (0.5627 versus 0.3111, P=0.038). In addition, a relationship between IL-18 expression of BMMC and initial white blood cell (WBC) was clearly demonstrated by a statistical analysis (r=0.806, P<0.001). These observations suggest that IL-18 gene over-expression might reflect the convergence of several important unfavorable prognostic factors in AML.
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Affiliation(s)
- Bin Zhang
- Chinese Academy of Medical Sciences & Peking Union Medical College, Institute of Hematology, National Laboratory of Experimental Hematology, 288 Nanjing Road, Tianjin, China
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38
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Nagai H, Hara I, Horikawa T, Oka M, Kamidono S, Ichihashi M. Gene transfer of secreted-type modified interleukin-18 gene to B16F10 melanoma cells suppresses in vivo tumor growth through inhibition of tumor vessel formation. J Invest Dermatol 2002; 119:541-8. [PMID: 12230493 DOI: 10.1046/j.1523-1747.2002.01866.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Interleukin-18 is a novel cytokine identified as a strong inducer of interferon-gamma. Interleukin-18 has been shown to have similar bioactivities to interleukin-12 and to have antitumor efficacy in experimental models. In this study, we investigated whether the introduction of the interleukin-18 gene to B16F10 melanoma cells can induce antitumor response or not. Before the transfection, we modified the interleukin-18 gene to enable transfected tumor cells to secrete bioactive interleukin-18, because interleukin-18 does not have a signal sequence and requires processing by the interleukin-1 converting enzyme to attain the mature form. We found that B16 melanoma cells transduced with hybrid cDNA consisting of the interferon-beta signal sequence and mature interleukin-18 sequence, but not native interleukin-18, secreted a large amount of interleukin-18 and exhibited retarded tumor growth when injected in syngeneic mice. The antitumor effect was mostly abrogated by administration of anti-interferon-gamma antibody, but was not affected by in vivo depletion of CD8+ T cells or natural killer cells. Histologic analysis revealed that vascularization was markedly reduced and that necrosis was extensively induced in interleukin-18-secreting B16F10 melanoma (B16/IL18) tissues, whereas abundant tumor vessel formation was observed in B16/IL18 tissues of interferon-gamma-neutralized mice. We also found that chemokines, interferon-inducible protein-10 and monokine induced by interferon-gamma, were produced in B16/IL18 tissues and that the expression of both chemokines was dependent on that of interferon-gamma in the tumor tissues. Further, we showed that B16 melanoma cells secreted both chemokines in response to interferon-gamma. In addition, the expression of angiogenin, an angiogenic factor of melanoma, in B16 melanoma cells was reduced by interferon-gamma treatment. These results indicate that gene transfer of secreted-type interleukin-18 to B16F10 melanoma cells is a useful method of triggering an antitumor response without any systemic adverse effects and that the antitumor efficacy is mainly mediated by antiangiogenic activity, which is possibly involved in at least two dynamic changes induced by interferon-gamma inside B16 melanoma cells: the upregulation of antiangiogenic chemokines, interferon-inducible protein-10 and monokine induced by interferon-gamma, and the downregulation of angiogenic factor, angiogenin.
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Affiliation(s)
- Hiroshi Nagai
- Department of Dermatology, Kobe University School of Medicine, Kobe, Japan.
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39
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Günel N, Coşkun U, Sancak B, Günel U, Hasdemir O, Bozkurt S. Clinical importance of serum interleukin-18 and nitric oxide activities in breast carcinoma patients. Cancer 2002; 95:663-7. [PMID: 12209760 DOI: 10.1002/cncr.10705] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
BACKGROUND Interleukin-18 (IL-18) is a novel immunoregulatory cytokine that was known previously as interferon-gamma-inducing factor. IL-18 levels can be used as a serum indicator for monitoring the clinical course of patients with hematologic malignancies and gastric carcinoma. Nitric oxide (NO) is a pleiotropic molecule that participates in the multistep processing of carcinogenesis. METHODS In the current study, we measured serum IL-18 and nitrate and nitrite levels in 38 metastatic and 26 nonmetastatic breast carcinoma patients and 16 healthy control subjects. Serum nitrate and nitrite levels were measured as an index of NO generation. RESULTS The levels of serum IL-18 and nitrate and nitrite were increased significantly in breast carcinoma patients compared with control subjects (P < 0.001). Serum IL-18 levels were significantly higher in the metastatic patients compared with the nonmetastatic patients (P < 0.001). There was no difference in serum nitrate and nitrite levels between metastatic and nonmetastatic patients (P > 0.05). Patients with bone metastasis have higher serum IL-18 levels and lower serum nitrate and nitrite levels compared with patients with liver, lung, and local metastasis (P < 0.001). There was no correlation among serum IL-18, nitrate and nitrite, CA 15-3, and carcinoembryonic antigen levels (P > 0.05). CONCLUSIONS These findings suggest that serum IL-18 and nitrate and nitrite levels may be useful markers in monitoring metastatic breast carcinoma patients. IL-18 and NO activities in breast carcinoma patients with bone metastasis may be more valuable in the follow-up of these patients.
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Affiliation(s)
- Nazan Günel
- Department of Medical Oncology, Gazi University Medical School, Ankara, Turkey.
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40
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Koyama N, Koschmieder S, Tyagi S, Nürnberger H, Wagner S, Böcker U, Hoelzer D, Gerhard Ottmann O, Kalina U. Differential effects of histone deacetylase inhibitors on interleukin-18 gene expression in myeloid cells. Biochem Biophys Res Commun 2002; 292:937-43. [PMID: 11944905 DOI: 10.1006/bbrc.2002.6753] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Histone deacetyrase (HDAC) inhibitors induce growth arrest and differentiation of leukemia cell lines and tumor cells derived from a large variety of human tissues. Here we showed that HDAC inhibitors sodium butyrate, TSA, and valproate regulated the expression of Interleukin-18 (IL-18), a cytokine with antitumor and proinflammatory properties, in human acute myeloid leukemia cell lines U937 and HEL. Sodium butyrate increased expression of IL-18 protein and mRNA and activated 1357bp IL-18 gene promoter construct. IL-18 mRNA level was up-regulated by TSA or valproate, which also activated IL-18 full-length promoter. While sodium butyrate or TSA stimulated the 108-bp IL-18 minimal promoter, valproate failed to activate it, indicating that valproate may use a distinct mechanism from sodium butyrate and TSA to activate IL-18 gene expression.
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Affiliation(s)
- Noriko Koyama
- Department of Hematology, Johann Wolfgang Goethe University, Frankfurt, 60590, Germany.
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41
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Uchimura T, Motomiya Y, Okamura H, Hashiguchi T, Miura M, Uji Y, Iwamoto H, Maruyama I. Marked increases in macrophage colony-stimulating factor and interleukin-18 in maintenance hemodialysis patients: comparative study of advanced glycation end products, carboxymethyllysine and pentosidine. Nephron Clin Pract 2002; 90:401-7. [PMID: 11961398 DOI: 10.1159/000054727] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Recent studies have demonstrated the crucial involvement of advanced glycation end products (AGEs) in major complications of long-term hemodialysis (HD) patients. HD, in a clinical setting, is characterized by increased production of proinflammatory cytokines. AGEs and cytokines are presumed to be responsible for the development of major complications in long-term HD. We therefore investigate here the relationship between a newly identified cytokine, interleukin-18 (IL-18), and two AGEs, carboxymethyllysine-hemoglobin (CML-Hb) and pentosidine. METHODS CML-Hb, pentosidine macrophage colony-stimulating factor (M-CSF), and IL-18 were evaluated in 35 patients undergoing stable maintenance HD. CML-Hb and pentosidine were measured by a dot blot and competitive ELISA. Cytokines were measured with a cytokine-specific ELISA. RESULTS Circulating levels of CML-Hb and pentosidine were elevated in HD patients as compared to controls. The serum values of M-CSF and IL-18 were significantly increased in the HD patients in comparison to controls. Moreover, these two AGEs and serum values of M-CSF, M-CSF and IL-18 showed significant correlation by simple and multiple regression analysis. CONCLUSION Elevation of circulating IL-18 levels was demonstrated in maintenance HD patients relative to controls. A correlative increase in M-CSF and IL-18 suggests the presence of a primed state of monocytes/macrophages in HD patients.
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Affiliation(s)
- Tomonori Uchimura
- Department of Laboratory Medicine, Kagoshima University School of Medicine, Japan
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Im SH, Kim SH, Azam T, Venkatesh N, Dinarello CA, Fuchs S, Souroujon MC. Rat interleukin-18 binding protein: cloning, expression, and characterization. J Interferon Cytokine Res 2002; 22:321-8. [PMID: 12034039 DOI: 10.1089/107999002753675749] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Interleukin-18 binding protein (IL-18BP) is a constitutively expressed and secreted protein that lacks a transmembrane domain. IL-18BP binds specifically to mature IL-18 and inhibits its activity. To study the immunomodulating role of IL-18BP in models of autoimmune diseases in rats, we cloned and characterized rat IL-18BP. Rat IL-18BP has 193 amino acid residues and is highly homologous to human and mouse IL-18BP. Recombinant rat IL-18BP binds to rat IL-18, reacts with antibodies to human or mouse IL-18BP, and inhibits IL-18-dependent interferon-gamma (IFN-gamma) production in vitro. Thus, rat IL-18BP can be employed to antagonize the proinflammatory responses induced by endogenous IL-18 in rat models of autoimmune diseases.
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Affiliation(s)
- Sin-Hyeog Im
- Department of Immunology, The Weizmann Institute of Science, Rehovot, 76100, Israel
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43
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Futani H, Okayama A, Matsui K, Kashiwamura S, Sasaki T, Hada T, Nakanishi K, Tateishi H, Maruo S, Okamura H. Relation between interleukin-18 and PGE2 in synovial fluid of osteoarthritis: a potential therapeutic target of cartilage degradation. J Immunother 2002; 25 Suppl 1:S61-4. [PMID: 12048352 DOI: 10.1097/00002371-200203001-00009] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Osteoarthritis (OA) is characterized by articular cartilage degradation and hypertrophic joint changes. Interleukin (IL)-18 is a potent inducer of prostaglandin (PG) E2 in vitro. We determined the relation between IL-18 and PGE2 in synovial fluid (SF) of human OA, and discussed the role of IL-18 in the pathogenesis of OA and also its therapeutic consequences. SF was collected from 30 patients with knee OA. The concentrations of IL-18 and other cytokines including IL-1beta, tumor necrosis factor (TNF)-alpha, IL-6, and IL-8 were measured by enzyme-linked immunosorbent assay (ELISA). The concentration of PGE2 was also assessed by inhibitory ELISA. The average value of IL-18 was 248 +/- 310 pg/mL. The average value of PGE2 was 93 +/- 103 pg/mL. There was a relatively strong correlation between IL-18 and PGE2 (r = 0.78, p = 0.0001). In contrast, IL-1beta was undetectable (cutoff point of 20 pg/mL), except for one case. TNF-alpha was also undetectable (cutoff point of 20 pg/mL), except for two cases. The average value of IL-6 was 1,310 +/- 2,623 pg/mL (n = 17), whereas IL-8 was 5,208 +/- 6,031 pg/mL (n = 5). Furthermore, IL-6 and IL-8 correlated with IL-18 (r = 0.69, p = 0.0024 and r = 0.87, p = 0.0527, respectively). Our results suggest that IL-18 could play a major role in vivo in inducing the production of PGE2, which in turn can cause cartilage degradation in OA pathogenesis. Thus, targeting this cytokine appears to be an important therapeutic approach in OA.
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Affiliation(s)
- Hiroyuki Futani
- Department of Orthopedic Surgery, Hyogo College of Medicine, Hyogo, Japan.
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Furuya D, Yagihashi A, Komatsu M, Masashi N, Tsuji N, Kobayashi D, Watanabe N. Serum interleukin-18 concentrations in patients with inflammatory bowel disease. J Immunother 2002; 25 Suppl 1:S65-7. [PMID: 12048353 DOI: 10.1097/00002371-200203001-00010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Elevated expression of interleukin (IL)-18 mRNA and protein in intestinal mucosa, attributable to activated monocytes and macrophages in that site, has been reported in patients with inflammatory bowel disease (IBD). However, changes in serum IL-18 concentrations in patients with IBD have not been reported. We measured bioactive IL-18 in serum from patients with IBD, using an enzyme-linked immunosorbent assay (ELISA). Mean serum IL-18 concentrations in 5 patients with Crohn disease (CD) were 400 pg/mL, approximately 1.7 times higher than concentrations in 21 control subjects (p < 0.01). However, serum IL-18 was not increased in patients with ulcerative colitis (UC). These results suggest that like other T-helper type 1 (Th1) cytokines IL-18 may play a key pathogenetic role in Th1-mediated disorders, such as CD. Regulation and expression of IL-18 appears to differ between CD and UC, and serum IL-18 may be a useful clinical marker for CD.
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Affiliation(s)
- Daisuke Furuya
- Division of Laboratory Diagnosis, Sapporo Medical University School of Medicine, Sapporo, Japan
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45
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Curran B, O'Connor JJ. The pro-inflammatory cytokine interleukin-18 impairs long-term potentiation and NMDA receptor-mediated transmission in the rat hippocampus in vitro. Neuroscience 2002; 108:83-90. [PMID: 11738133 DOI: 10.1016/s0306-4522(01)00405-5] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The effects of the pro-inflammatory cytokine interleukin-18 (IL-18) were investigated on both normal and isolated N-methyl-D-aspartate (NMDA) receptor-mediated field excitatory post synaptic potentials (fEPSP) and on the induction of long-term potentiation (LTP) in the rat dentate gyrus in vitro. Bath perfusion with IL-18 (100 ng/ml) for 20 min prior to high-frequency stimulation had no significant effect on baseline synaptic transmission or paired pulse depression, but did impair the induction of LTP (115.7+/-8.8% versus 150.8+/-8.1% in vehicle control slices, n=6, P<0.05 at 60 min). Further analysis demonstrated that IL-18 significantly depressed the amplitude of pharmacologically isolated NMDA receptor-mediated fEPSP (NMDA-fEPSP; 77.4+/-4.3% of baseline compared to controls at 1 h; P<0.05, n=7), an effect that may underlie the impairment of LTP by IL-18. This action of IL-18 on LTP and NMDA-fEPSPs was attenuated in full by pretreatment of slices with exogenously applied IL-1 receptor antagonist (IL-1ra, 100 ng/ml), the naturally occurring antagonist of IL-1 type 1 receptors. This ability of IL-1ra to block the inhibitory effects of IL-18 is likely to be receptor-specific as no reversal of the tumour necrosis factor-alpha-induced inhibition of LTP was seen with IL-1ra administration (110.7+/-5.4% versus tumour necrosis factor-alpha-treated slices; 107.4+/-8.7%, P=0.6, n=6). These are the first experiments providing evidence of a direct neuromodulatory role for IL-18 in synaptic plasticity.
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Affiliation(s)
- B Curran
- Department of Human Anatomy and Physiology, Conway Institute of Biomolecular and Biomedical Research, National University of Ireland, Dublin
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El-Mezzein RE, Matsumoto T, Nomiyama H, Miike T. Increased secretion of IL-18 in vitro by peripheral blood mononuclear cells of patients with bronchial asthma and atopic dermatitis. Clin Exp Immunol 2001; 126:193-8. [PMID: 11703360 PMCID: PMC1906188 DOI: 10.1046/j.1365-2249.2001.01664.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/13/2001] [Indexed: 11/20/2022] Open
Abstract
This study was performed to determine whether or not IL-18, formerly called IFN-gamma-inducing factor, is involved in the pathogeneses of allergic disorders. Peripheral blood mononuclear cells (PBMC) were obtained from patients with allergic bronchial asthma (BA), patients with atopic dermatitis (AD) and controls who did not have any allergic disease, and then cultured with lipopolysaccharide (LPS) or phytohaemagglutinin (PHA). The concentrations of IL-18, IFN-gamma and IL-13 in supernatant fluids were determined by enzymatic immunoassaying, and the expression of IFN-gamma messenger (m) RNA in the cells was measured by colorimetric microplate assaying. IL-18 secretion in the BA patients (geometric mean (gm) = 189 pg/ml) and AD patients (gm = 172 pg/ml) was significantly higher than that in non-allergic controls (gm = 118 pg/ml). In contrast, IFN-gamma secretion in the BA patients (gm = 7.3 IU/ml) and AD patients (gm = 6.8 IU/ml) was significantly lower than that in non-allergic controls (gm = 20.7 IU/ml). The amounts of IL-13 in supernatant fluids and IFN-gamma mRNA in cells were not statistically different among the BA patients, AD patients and non-allergic controls. The possible involvement of IL-18 in allergic disorders is discussed.
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Affiliation(s)
- R E El-Mezzein
- Department of Child Development, Kumamoto University School of Medicine, Kumamoto, Japan
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47
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Siegmund B, Fantuzzi G, Rieder F, Gamboni-Robertson F, Lehr HA, Hartmann G, Dinarello CA, Endres S, Eigler A. Neutralization of interleukin-18 reduces severity in murine colitis and intestinal IFN-gamma and TNF-alpha production. Am J Physiol Regul Integr Comp Physiol 2001; 281:R1264-73. [PMID: 11557635 DOI: 10.1152/ajpregu.2001.281.4.r1264] [Citation(s) in RCA: 209] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Interleukin (IL)-18, initially described as interferon (IFN)-gamma-inducing factor, is expressed in the inflamed mucosa of patients with Crohn's disease. To investigate the role of IL-18 in intestinal inflammation, the effect of neutralizing antimurine IL-18 antiserum in dextran sulfate sodium (DSS)-induced colitis in BALB/c and C57BL/6 mice was examined. During a dose response of DSS, levels of colonic IL-18 increased parallel with clinical worsening. With the use of confocal laser microscopy, the increased IL-18 was localized to the intestinal epithelial layer. Anti-IL-18 treatment resulted in a dose-dependent reduction of the severity of colitis in both BALB/c and C57BL/6 mice. Colon shortening following DSS-induced colitis was partially prevented in the treatment groups. In the colon tissue homogenates, IFN-gamma concentrations were lower in the anti-IL-18-treated DSS-fed mice compared with untreated DSS-fed mice. This suppressive effect of anti-IL-18 administered in vivo was also observed on spontaneous tumor necrosis factor-alpha, IL-18, and IFN-gamma production from ex vivo colon organ cultures. The stimulation of lamina propria mononuclear cells by IL-18 and IL-12 resulted in a synergistic increase in IFN-gamma synthesis. These findings suggest that IL-18 is a pivotal mediator in experimental colitis.
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Affiliation(s)
- B Siegmund
- Department of Medicine, University of Colorado Health Sciences Center, Denver, Colorado 80206, USA.
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48
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Im SH, Barchan D, Maiti PK, Raveh L, Souroujon MC, Fuchs S. Suppression of experimental myasthenia gravis, a B cell-mediated autoimmune disease, by blockade of IL-18. FASEB J 2001; 15:2140-8. [PMID: 11641240 DOI: 10.1096/fj.01-0072com] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Interleukin-18 (IL-18) is a pleiotropic proinflammatory cytokine that plays an important role in interferon gamma (IFN-gamma) production and IL-12-driven Th1 phenotype polarization. Increased expression of IL-18 has been observed in several autoimmune diseases. In this study we have analyzed the role of IL-18 in an antibody-mediated autoimmune disease and elucidated the mechanisms involved in disease suppression mediated by blockade of IL-18, using experimental autoimmune myasthenia gravis (EAMG) as a model. EAMG is a T cell-regulated, antibody-mediated autoimmune disease in which the nicotinic acetylcholine receptor (AChR) is the major autoantigen. Th1- and Th2-type responses are both implicated in EAMG development. We show that treatment by anti-IL-18 during ongoing EAMG suppresses disease progression. The protective effect can be adoptively transferred to naive recipients and is mediated by increased levels of the immunosuppressive Th3-type cytokine TGF-beta and decreased AChR-specific Th1-type cellular responses. Suppression of EAMG is accompanied by down-regulation of the costimulatory factor CD40L and up-regulation of CTLA-4, a key negative immunomodulator. Our results suggest that IL-18 blockade may potentially be applied for immunointervention in myasthenia gravis.
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MESH Headings
- Abatacept
- Animals
- Antibodies/therapeutic use
- Antigens, CD
- Antigens, Differentiation/biosynthesis
- B-Lymphocytes/immunology
- CD40 Ligand/metabolism
- CTLA-4 Antigen
- Cells, Cultured
- Cytokines/biosynthesis
- Disease Progression
- Female
- Hypersensitivity, Delayed/therapy
- Immunoconjugates
- Immunoglobulin G/biosynthesis
- Interleukin-18/antagonists & inhibitors
- Interleukin-18/immunology
- Kinetics
- Lymphocyte Activation
- Myasthenia Gravis, Autoimmune, Experimental/immunology
- Myasthenia Gravis, Autoimmune, Experimental/therapy
- Rats
- Rats, Inbred Lew
- Receptors, Nicotinic/immunology
- T-Lymphocytes/immunology
- Th1 Cells/immunology
- Transforming Growth Factor beta/biosynthesis
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Affiliation(s)
- S H Im
- Department of Immunology, The Weizmann Institute of Science, Rehovot 76100, Israel
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Amo Y, Ohta Y, Hamada Y, Katsuoka K. Serum levels of interleukin-18 are increased in patients with cutaneous T-cell lymphoma and cutaneous natural killer-cell lymphoma. Br J Dermatol 2001; 145:674-6. [PMID: 11703305 DOI: 10.1046/j.1365-2133.2001.04420.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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50
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Novick D, Schwartsburd B, Pinkus R, Suissa D, Belzer I, Sthoeger Z, Keane WF, Chvatchko Y, Kim SH, Fantuzzi G, Dinarello CA, Rubinstein M. A novel IL-18BP ELISA shows elevated serum IL-18BP in sepsis and extensive decrease of free IL-18. Cytokine 2001; 14:334-42. [PMID: 11497494 DOI: 10.1006/cyto.2001.0914] [Citation(s) in RCA: 210] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
IL-18 binding protein (IL-18BP) is a circulating antagonist of the proinflammatory Th1 cytokine IL-18. It effectively blocks IL-18 by forming a 1:1 high affinity (Kd=400 pM) complex, exhibiting a very low dissociation rate. We have developed a sandwich ELISA for IL-18BPa and determined its limit of detection (62 pg/ml). Interference by IL-18 and related cytokines, as well as cross reactivity with other IL-18BP isoforms (b, c, and d) were determined. Using this ELISA, we measured serum IL-18BPa in large cohorts of healthy individuals and in septic patients. Serum IL-18BPa in healthy individuals was 2.15+/-0.15 ng/ml (range 0.5-7 ng/ml). In sepsis, the level rose to 21.9+/-1.44 ng/ml (range 4-132 ng/ml). Total IL-18 was measured in the same sera by an electrochemiluminescence assay and free IL-18 was calculated based on the mass action law. Total IL-18 was low in healthy individuals (64+/-17 pg/ml) and most of it ( approximately 85%) was in its free form. Total IL-18 and IL-18BPa were both elevated in sepsis patients upon admission (1.5+/-0.4 ng/ml and 28.6+/-4.5 ng/ml, respectively). At these levels, most of the IL-18 is bound to IL-18BPa, however the remaining free IL-18 is still higher than in healthy individuals. We conclude that IL-18BPa considerably inhibits circulating IL-18 in sepsis. Yet, exogenous administration of IL-18BPa may further reduce circulating IL-18 activity.
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Affiliation(s)
- D Novick
- Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, 76100, Israel
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