Human IL-1 Beta Research Articles

The Role of ETO and CtBP1 in CBFA2T3-GLIS2 Mediated Transcriptional Regulation and Leukemogenesis

CBFA2T3-GLIS2 is the most prevalent fusion oncogene in pediatric acute megakaryoblastic leukemia patients without Down syndrome and is associated with an event free survival of only 8%. A cryptic inversion event on chromosome 16 joins the three nervy homology regions (NHR) of CBFA2T3 to the five zinc fingers of GLIS2. This configuration enables the encoded chimeric transcription factor to bind GLIS2 consensus sequences throughout the genome and recruit transcriptional activators and repressors to alter gene expression and enhance self-renewal capability. Few cooperating mutations have been identified in patients harboring this fusion which suggests it is the sole oncogenic driver. The molecular mechanism by which CBFA2T3-GLIS2 drives leukemogenesis is not fully understood. Identification of components critical to the transcriptional complex and their role in gene regulation may reveal novel therapeutic targets to improve patient outcomes. Studies on the wild type CBFA2T3 and GLIS2 proteins have demonstrated interactions with the transcriptional regulators ETO and CtBP1 respectively. Further p300 has been shown to play a role in transcriptional regulation imparted by both transcription factors. We therefore hypothesize the fusion promotes transcriptional activation when the histone acetyltransferase p300 and the transcription factor ETO are recruited through NHR1 and NHR2, respectively. When the co-repressor CtBP1 is recruited through the PXDLS motif, located in the GLIS2 portion of the fusion, transcriptional repression predominates. Association of these co-factors with the fusion was confirmed through co-immunoprecipitations. Site-directed mutagenesis was then used to systematically delete NHR1 and NHR2 and mutate the PXDLS motif to evaluate the resultant effects on transcriptional regulation, self-renewal, and leukemogenesis imparted by the fusion. A luciferase reporter assay was used to assess transcriptional activation of the BMP2 promoter, a gene which is known to be upregulated by the CBFA2T3-GLIS2 fusion. Loss of NHR1, NHR2, or NHR3 did not alter the ability of the fusion to activate transcription. In contrast, loss of NHR1 and NHR2 in combination (NHR1-2Δ) and mutation of the PXDLS domain decreased transcriptional activation compared to the wild type fusion. The effect of the mutations on self-renewal capability was then evaluated through colony formation assays. Consistent with the luciferase reporter assay, NHR1-2Δ and PXDLS mutants decreased the number of colonies at week six compared to the unmanipulated fusion. Next, we investigated the effect of these mutations on leukemogenesis. Murine models harboring the CBFA2T3-GLIS2 fusion without cooperating mutations have been unsuccessful and patient-derived xenograft models are limited and difficult to manipulate. Therefore, we developed a novel in vivo model of CBFA2T3-GLIS2 driven leukemia. CD34+ stem cells were isolated from human cord blood and transduced with a lentivirus construct encoding the fusion and a GFP reporter. The cells were then differentiated to megakaryoblasts using human TPO and IL1-beta and sorted for purity prior to injection into immunodeficient NSG-SGM3 recipient mice. The fusion positive human primary megakaryoblasts induced a serially transplantable leukemia within 180 days that recapitulates CBFA2T3-GLIS2 positive patient specimens on a transcriptional and protein level. In contrast to our in vitro studies where NHR2 deletion alone did not alter transcriptional activation and self-renewal, the loss of this domain abrogated leukemogenesis in vivo, suggesting a dependency on the association of ETO with the fusion. Mice that received PXDLS mutant cells, however, developed leukemia at a normal latency suggesting that CtBP1 is not required. This study confirms the CBFA2T3-GLIS2 fusion is sufficient for oncogenic transformation of human CD34+ stem cells. We demonstrate that disruption of ETO, p300, and CtBP1 recruitment to the transcriptional complex decreases transcriptional regulation and self-renewal imparted by the fusion. The loss of ETO was the most detrimental to leukemogenesis in our murine model, uncovering a potential new pathway for the development of targeted therapies. Ongoing studies include CUT&RUN sequencing for the fusion, ETO, and CtBP1 to determine co-occupancy of target genes to further understand those that are critical in transformation. DisclosuresGruber: Kura Oncology: Consultancy.

CRISPR gene-engineered CYBBko THP-1 cell lines highlight the crucial role of NADPH-induced reactive oxygen species for regulating inflammasome activation

Summary CRISPR-Cas9 engineered CYBBko THP-1 cell lines display an inflammatory profile with increased IL-1β, IL-6 and TNF-α secretion as consequence of NADPH-induced ROS deficiency. This phenotype is reminiscent of the one observed in phagocytes from CGD patients.

Interleukin-1 Beta Promotes the Expression of Prox-1 and Vascular Endothelial Growth Factor Receptor Type-3 in Adult Human Dermal Fibroblasts

Abstract 4738 Background and Aims:We recently reported that human interleukin 1 beta (IL-1 beta) stimulates bone-marrow stromal myofibroblasts to express a hematopoietic stem cell marker, CD34 (16th EHA, and 53rdASH meeting). To characterize precisely the effects of IL-1 beta to the stromal cells, adult human dermal fibroblasts (HDF) were cultured with IL-1 beta, and the morphological changes and molecular expressions were observed. Materials and Methods:HDF were purchased, and cultured in knockout DMEM medium with 15% KSR with or without recombinant human IL-1 beta for 3 weeks. The morphological changes and the expression of specific hematopoiesis-related genes were analyzed time-dependently. The concentration of hematopoietic growth factors in the culturing supernatants was also measured. Results:When HDF were cultured with human IL-1 beta for 3 weeks, the cellular morphology changed to the filamentous appearance. RT-PCR analyses revealed that cells expressed Prox-1, a master molecule for lymphatic duct neogenesis, and also vascular endothelial growth factor receptor (VEGFR) type-3. Smad7 and PAI1 were also expressed; however, LYVE1, a marker for lymphatic vascular endothelial cell, was not induced. VEGF-C production was also demonstrated at RNA and protein levels, and VEGF-C and VEGFR type-3 system played an important role in morphological changes and cell-proliferation. Discussion:We previously reported that when HDF were cultured in DMEM/F12 medium with IL-1 beta and EPO, hematopoietic markers were induced. When HDF were cultured in knockout DMEM, a condition for immature cell-growth at ES cell levels, and IL-1 beta, lymphatic duct neogenesis-related genes were activated, and HDF converted their morphology without an introduction of any genes externally. We are now making clear the precise action of IL-1 beta to HDF using microarray analysis. Disclosures:No relevant conflicts of interest to declare.

Efficacy and safety of the human anti-IL-1beta monoclonal antibody canakinumab in rheumatoid arthritis: results of a 12-week, phase II, dose-finding study

BackgroundCanakinumab is a fully human anti-interleukin IL-1beta monoclonal antibody, being investigated for the treatment of rheumatoid arthritis (RA). This multicenter, phase II, randomized, double-blind, placebo-controlled, parallel-group, dose-finding study investigated the efficacy and safety of canakinumab in patients with active RA despite ongoing therapy at stable doses of methotrexate.MethodsPatients were randomized to receive one of four regimens, in addition to methotrexate, for 12 weeks: canakinumab 150 mg subcutaneously (SC) every 4 weeks (q4wk), canakinumab 300 mg SC (2 injections of 150 mg SC) every 2 weeks, a 600 mg intravenous loading dose of canakinumab followed by 300 mg SC every 2 weeks', or placebo SC every 2 weeks.ResultsAmong 274 patients with evaluable efficacy data, the percentage of responders according to American College of Rheumatology 50 criteria (the primary endpoint, based on a 28-joint count) was significantly higher with canakinumab 150 mg SC q4wk than with placebo (26.5% vs. 11.4%, respectively; p = 0.028). Compared to placebo, this dosage of canakinumab was also associated with significantly more favorable responses at week 12 with respect to secondary endpoints including the Disease Activity Score 28, scores on the Health Assessment Questionnaire and Functional Assessment of Chronic Illness Therapy-Fatigue, swollen 28-joint count, and patient's and physician's global assessments of disease activity. No safety concerns were raised with canakinumab therapy, particularly with regard to infections. Few injection-site reactions occurred.ConclusionThe addition of canakinumab 150 mg SC q4wk improves therapeutic responses among patients who have active RA despite stable treatment with methotrexate.Trial Registration(ClinicalTrials.gov identifier: NCT00784628)

IL-1-Antagonisten

Interleukin (IL)-1 plays an important role not only in the mediation of inflammation but also in the destruction of cartilage and bone. Together with TNF-alpha it is one of the most important cytokines in the pathogenesis of rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA). The first IL-1 antagonist to be approved for RA was Anakinra, an IL-1 receptor antagonist. Anakinra appears to be less effective for RA than TNF blockers. Hence, Anakinra is rarely used for the treatment of RA, but more for the treatment of IL-1-mediated diseases such as autoinflammatory syndromes, adult-onset Still's disease and systemic onset JIA. Two newer IL-1 antagonists have recently been approved for the treatment of CAPS (cryopyrin-associated periodic syndromes): Canakinumab, a fully human IL-1beta antibody, and rilonacept, a fusion protein consisting of the ligand-binding domain of the IL-1 receptor and the IL-1-receptor accessory protein, bound to human IgG1. For RA, there is only one proof-of-concept study to date with canakinumab. There are no prospective data for the treatment of patients with RA who did not respond to or tolerate TNF antagonists; in a retrospective analysis, only 8% of anti-TNF pretreated patients achieved an ACR 20 response.

Cyclooxygenase‐1 mediates prostaglandin E2 elevation and contextual memory impairment in a model of sustained hippocampal interleukin‐1β expression

Interleukin (IL)-1beta is a proinflammatory cytokine implicated in several neurodegenerative disorders. Downstream actions of IL-1beta include production of prostaglandin (PG) E(2) by increasing expression of cyclooxygenase (COX) enzymes and prostaglandin E synthase (PGES) isoforms. We recently developed a transgenic mouse carrying a dormant human IL-1beta eXcisional Activation Transgene (XAT) for conditional and chronic up-regulation of IL-1beta in selected brain regions. This model is characterized by regionally specific glial activation, immune cell recruitment, and induction of cytokines and chemokines. Here, we aimed to elucidate the effects of long-term IL-1beta expression on the PGE(2) synthetic pathway and to determine the effects of PGs on inflammation and memory in our model. As expected, PGE(2) levels were significantly elevated after IL-1beta up-regulation. Quantitative real-time PCR analysis indicated significant induction of mRNAs for COX-1 and membranous PGES-1, but not COX-2 or other PGES isoforms. Immunohistochemistry revealed elevation of COX-1 but no change in COX-2 following sustained IL-1beta production. Furthermore, pharmacological inhibition of COX-1 and use of COX-1 knockout mice abrogated IL-1beta-mediated PGE(2) increases. Although COX-1 deficient mice did not present a dramatically altered neuroinflammatory phenotype, they did exhibit improved contextual fear memory. This data suggests a unique role for COX-1 in mediating chronic neuroinflammatory effects through PGE(2) production.

β6 Integrin Subunit Deficiency Alleviates Lung Injury in a Mouse Model of Bronchopulmonary Dysplasia

Pulmonary inflammation is associated with the development of bronchopulmonary dysplasia in premature infants. We have previously shown that perinatal pulmonary expression of human IL-1beta is sufficient to cause a lung disease similar to bronchopulmonary dysplasia, characterized by inflammation, impaired alveolarization, poor postnatal growth, and increased mortality in infant mice. The alphavbeta6 integrin plays a critical role in regulating inflammation in the adult lung. To study the role of the beta6 integrin subunit in neonatal inflammatory lung disease, we compared the pulmonary development in IL-1beta-expressing infant mice with wild-type or null beta6 integrin loci. Absence of the beta6 integrin subunit decreased the mortality and improved the postnatal growth of IL-1beta-expressing pups. The disrupted alveolar development of IL-1beta-expressing mice was improved by beta6 integrin deficiency. IL-1beta-expressing beta6(-/-) pups had shorter alveolar chord length and thinner alveolar walls than IL-1beta-expressing beta6(+/+) pups. In addition, the absence of the beta6 integrin subunit reduced IL-1beta-induced neutrophil and macrophage infiltration into the alveolar spaces. beta6 integrin subunit deficiency suppressed inflammation and goblet cell hyperplasia in the airways and alleviated airway remodeling in IL-1beta-expressing mice. The expression of the chemoattractant proteins, keratinocyte-derived chemokine, macrophage-inflammatory protein-2, calgranulin A, and calgranulin B, of osteopontin, and of the chitinase-like lectins, Ym1 and Ym2, was lower in IL-1beta-expressing beta6(-/-) than in IL-1beta-expressing beta6(+/+) mice. We conclude that absence of the beta6 integrin subunit protects the infant murine lung against IL-1beta-induced inflammation and injury.

Maternal IL-1β Production Prevents Lung Injury in a Mouse Model of Bronchopulmonary Dysplasia

Little is known about the influence of maternal inflammation on neonatal outcome. Production of IL-1beta in the lungs of newborn infants is associated with bronchopulmonary dysplasia. Using bitransgenic (bi-TG) mice in which human (h) IL-1beta is expressed with a doxycycline-inducible system controlled by the Clara cell secretory protein promoter, we have shown that hIL-1beta expression causes a bronchopulmonary dysplasia-like illness in infant mice. To study the hypothesis that maternal hIL-1beta production modifies the response of the newborn to hIL-1beta, doxycycline was administered to bi-TG and control dams from Embryonic Day 0, inducing production of hIL-1beta by the bi-TG dams before hIL-1beta production started in their bi-TG fetuses, or from Embryonic Day 15, inducing simultaneous production of hIL-1beta by both the bi-TG dams and their bi-TG fetuses. In addition to the lungs, hIL-1beta was expressed at low levels in the uteri of bi-TG dams. Maternal inflammation preceding fetal inflammation increased the survival and growth of hIL-1beta-expressing pups, enhanced alveolarization, and protected the airways against remodeling and goblet cell hyperplasia. Maternal hIL-1beta production preceding fetal hIL-1beta production caused silencing of several inflammatory genes, including CXC and CC chemokines, murine IL-1beta, serum amyloid A3, and Toll-like receptors 2 and 4, and suppressed the expression of chitinase-like lectins Ym1 and Ym2 in the lungs of infant mice. Maternal inflammation protects the newborn against subsequent hIL-1beta-induced lung inflammation and injury. In contrast, induction of hIL-1beta production simultaneously in bi-TG dams and their fetuses offered no protection against inflammatory lung disease in the neonate.

Screening and identification of novel B cell epitopes in human heparanase and their anti-invasion property for hepatocellular carcinoma.

The aim of this study was to screen and identify novel B cell epitopes within the human heparanase protein and to investigate the impact of self-developed anti-heparanase polypeptide antibodies on growth and invasion of HCCLM6 human hepatocellular carcinoma cells in vitro. The flexible regions of secondary structure and the B cell epitopes of the human heparanase amino acid sequence were predicted by DNAStar and Bcepred software.The multiple antigenic peptides (MAP) of the epitopes were synthesized in eight-branched form. Rabbits were immunized with the eight-branched MAPs mixed with the universal T-helper epitope human IL-1beta peptide (VQGEESNDK, amino acid 163-171). The immunogenicity of the synthesized peptides was evaluated by ELISA, western blot and immunohistochemistry. The impact of the self-developed rabbit anti-heparanase polyclonal antibodies on growth and invasion ability of HCCMLM6 cells were analyzed in a cell culture model. The cells were first treated with one of the three antibodies, respectively, and then measured by using MTT, flow cytometry, plate clone formation, invasion assay and heparan sulfate degrading enzyme assay. The three amino acid sequences 1-15 (MAP1), 279-293 (MAP2), and 175-189 (MAP3) in the large subunit of the human heparanase protein were predicted as its most potential epitopes. ELISA, western blot and immunohistochemistry analysis showed that all three MAPs were capable to induce high titer of serum antibodies. Antibodies induced by MAP1 and MAP2 were high specific. Furthermore, anti-MAP2 antibodies showed the strongest avidity towards liver cancer tissues. Under the treatment with the three anti-heparanase antibodies, respectively, the growth, cell cycle and clone formation of the cells remained unchanged when compared with a treatment with normal rabbit IgG. However, an inhibition of cell invasiveness and heparanase activity could be detected under the treatment with anti-MAP1- or anti-MAP2-antibody (with a terminal concentration of 100 mug/ml). The cell invasiveness was decreased by 54 and 38%, respectively, the heparanase activity by 43 and 39%, respectively. The multiple antigenic peptides MAP1 (AC 1-15) and MAP2 (AC 279-293) may be the dominant B cell epitopes in the human heparanase protein. The induced polypeptide antibodies can effectively inhibit the heparanase activity of HCCLM6 liver cancer cells and therefore influence their invasion ability, which provides a theoretic basis for the development of anti-heparanase antibodies and their clinical use as vaccine.

Determination of the contributions of individual aromatic residues to the CD spectrum of IL-1 beta using site directed mutagenesis.

Circular dichroism (CD) spectra have been measured in the aromatic region for recombinant human interleukin IL-1 beta and for site specific mutants in which each of the four tyrosines and the single tryptophan residue have been replaced one at a time by phenylalanine. These mutant proteins have been shown to have conformations that are closely similar to that of the wild type protein. By comparing the spectrum of each mutant with that of the wild type human protein it has been possible to assess the contribution of each aromatic residue to the CD spectrum of the latter. It has been shown that the spectrum is largely a result of contributions from Trp 120 and from Tyr 68.

Matrix Metalloproteinase-9 Deficiency Worsens Lung Injury in a Model of Bronchopulmonary Dysplasia

Increased activity of matrix metalloproteinase (MMP)-9 is associated with the development of bronchopulmonary dysplasia (BPD) in newborn infants, but the role of MMP-9 in the pathophysiology of BPD is unclear. We have shown that perinatal expression of interleukin-1 beta (IL-1 beta) in the lung is sufficient to cause a BPD-like illness in infant mice. To study the hypothesis that MMP-9 is an important downstream mediator in IL-1 beta-induced lung injury in the newborn, we compared the effects of IL-1 beta on fetal and postnatal lung inflammation and development in transgenic mice with regulatable pulmonary overexpression of human mature IL-1 beta with wild-type (IL-1 beta/MMP-9(+/+)) or null (IL-1 beta/MMP-9(-/-)) MMP-9 loci. IL-1 beta increased the expression of MMP-9 mRNA and amount of MMP-9 protein in the lungs of MMP-9(+/+) mice. IL-1 beta/MMP-9(-/-) mice had fewer neutrophils but more macrophages in the lungs than did IL-1 beta/MMP-9(+/+) mice. MMP-9 deficiency increased pulmonary cell death and macrophage clearance of dying cells in IL-1 beta-expressing mice. IL-1 beta/MMP-9(-/-) mice had more severe alveolar hypoplasia than IL-1 beta/MMP-9(+/+) mice, implying that IL-1 beta-induced lung disease was worsened in the absence of MMP-9. These results suggest that MMP-9 activity in the inflamed neonatal lung protects the lung against injury.

Patients with Chronic Mucocutaneous Candidiasis Exhibit Reduced Production of Th17-Associated Cytokines IL-17 and IL-22

Chronic mucocutaneous candidiasis (CMC) constitutes a selective inability to clear infection with the yeast Candida, resulting in persistent debilitating inflammation of skin, nails, and mucous membranes. The underlying defect is unknown. Only recently, IL-17-producing T cells have been reported to be involved in clearing Candida infections. In order to characterize T cellular immune response to Candida, we analyzed T-cell cytokine secretion to Candida antigen and mitogenic stimuli in CMC patients, immunocompetent patients suffering from acute Candida infection, and healthy volunteers. Peripheral blood mononuclear cells (PBMCs) from CMC patients produced significantly lower amounts of IL-17 and IL-22 mRNA and protein when stimulated with Candida albicans or mitogen in vitro compared with that in matched healthy individuals. Additionally, PBMCs from immunocompetent Candida-infected patients secreted more IL-17 and IL-22 than those of both CMC patients and healthy, non-infected controls. Flow cytometry revealed a decreased number of CCR6+ IL-17-producing T cells in CMC patients, whereas the amount of CCR6+/CCR4+ cells was not altered. Levels of differentiating cytokines for human Th17 cells, IL-1beta and IL-6, tended to be higher in CMC patients. The inability to clear C. albicans in CMC patients could be due to a defect in the immune response of IL-17-producing T cells.

Overexpression of Interleukin-1β Induces Gastric Inflammation and Cancer and Mobilizes Myeloid-Derived Suppressor Cells in Mice

Polymorphisms of interleukin-1beta (IL-1beta) are associated with an increased risk of solid malignancies. Here, we show that stomach-specific expression of human IL-1beta in transgenic mice leads to spontaneous gastric inflammation and cancer that correlate with early recruitment of myeloid-derived suppressor cells (MDSCs) to the stomach. IL-1beta activates MDSCs in vitro and in vivo through an IL-1RI/NF-kappaB pathway. IL-1beta transgenic mice deficient in T and B lymphocytes develop gastric dysplasia accompanied by a marked increase in MDSCs in the stomach. Antagonism of IL-1 receptor signaling inhibits the development of gastric preneoplasia and suppresses MDSC mobilization. These results demonstrate that pathologic elevation of a single proinflammatory cytokine may be sufficient to induce neoplasia and provide a direct link between IL-1beta, MDSCs, and carcinogenesis.

Lipopolysaccharide (LPS) down-regulates CD4 expression in primary human macrophages through induction of endogenous tumour necrosis factor (TNF) and IL-1 beta.

The regulation of CD4 expression on macrophages and its role in immune cell interactions remain obscure. In contrast with primary lymphocytes, primary macrophages express only low amounts of surface CD4, which is regulated differentially for example by adherence in vitro. We report that addition of LPS for 1-5 days to human blood monocyte tissue culture-derived macrophages (TCDM) down-regulates both surface CD4 expression and total cellular CD4 antigen content as measured by flow cytometry and Western blot analysis. TNF-alpha and IL-1 beta, proinflammatory cytokines which are both induced by LPS, also down-regulate surface and total CD4 expression in TCDM. This down-regulation of CD4 expression by LPS, TNF-alpha, and IL-1 beta occurs at the level of transcription. The decreased macrophage CD4 expression induced by LPS was blocked by MoAbs directed against human TNF-alpha and IL-1 beta, demonstrating that LPS acts on CD4 expression through induction of endogenous TNF-alpha and IL-1 beta. Conversely, neither LPS nor TNF-alpha and IL-1 beta were able to modulate surface CD4 expression on quiescent or phytohaemagglutinin (PHA)-activated lymphocytes. Of other cytokines and growth factors tested, Th2 cytokines (IL-4, IL-10, IL-13), chemokines (MCP-1, MIP-1 alpha, RANTES), and macrophage colony-stimulating factor did not alter CD4 expression in primary macrophages; granulocyte-monocyte colony-stimulating factor and the prototypal Th1 cytokine interferon-gamma (IFN-gamma) modulated surface CD4 expression only after prolonged treatment (5 days). Our results show that LPS, TNF-alpha and IL-1 beta selectively down-regulate CD4 expression in primary human macrophages, and that decreased CD4 expression induced by LPS results from endogenous secretion of TNF-alpha and IL-1 beta by the macrophages.

The human anti-IL-1β monoclonal antibody ACZ885 is effective in joint inflammation models in mice and in a proof-of-concept study in patients with rheumatoid arthritis

IntroductionIL-1β is a proinflammatory cytokine driving joint inflammation as well as systemic signs of inflammation, such as fever and acute phase protein production.MethodsACZ885, a fully human monoclonal antibody that neutralizes the bioactivity of human IL-1β, was generated to study the potent and long-lasting neutralization of IL-1β in mechanistic animal models as well as in a proof-of-concept study in patients with rheumatoid arthritis (RA).ResultsThe mouse IL-1 receptor cross-reacts with human IL-1β, and it was demonstrated that ACZ885 can completely suppress IL-1β-mediated joint inflammation and cartilage destruction in mice. This observation prompted us to study the safety, tolerability and pharmacodynamic activity of ACZ885 in RA patients in a small proof-of-concept study – the first to be conducted in humans. Patients with active RA despite treatment with stable doses of methotrexate were enrolled in this dose escalation study. The first 32 patients were split into four cohorts of eight patients each (six were randomly assigned to active treatment and two to placebo). ACZ885 doses were 0.3, 1, 3 and 10 mg/kg, administered intravenously on days 1 and 15. To explore efficacy within 6 weeks of treatment, an additional 21 patients were randomly assigned to the 10 mg/kg cohort, resulting in a total of 20 patients dosed with 10 mg/kg and 15 patients treated with placebo. There was clinical improvement (American College of Rheumatology 20% improvement criteria) at week 6 in the 10 mg/kg treatment group; however, this did not reach statistical significance (P = 0.085). A statistically significant reduction in disease activity score was observed after 4 weeks in the 10 mg/kg group. Onset of action was rapid, because most responders exhibited improvement in their symptoms within the first 3 weeks. C-reactive protein levels decreased in patients treated with ACZ885 within 1 week. ACZ885 was well tolerated. Three patients receiving ACZ885 developed infectious episodes that required treatment. No anti-ACZ885 antibodies were detected during the study.ConclusionACZ885 administration to methotrexate-refractory patients resulted in clinical improvement in a subset of patients. Additional studies to characterize efficacy in RA and to determine the optimal dose regimen appear warranted.Trial RegistrationClinicalTrials.gov identifier NCT00619905.

Body Distributioin of RGD-mediated Liposome in Brain-targeting Drug Delivery

RGD conjugation liposomes (RGD-liposomes) were evaluated for brain-targeting drug delivery. The flow cytometric in vitro study demonstrated that RGD-liposomes could bind to monocytes and neutrophils effectively. Ferulic acid (4-hydroxy-3-methoxycinnamic, FA) was loaded into liposomes. Rats were subjected to intrastriatal microinjections of 100 units of human recombinant IL-1beta to produce brain inflammation and caudal vein injection of three formulations (FA solution, FA liposome and RGD-coated FA liposome). Animals were sacrificed 15, 30, 60 and 120 min after administration to study the body distribution of the FA in the three formulations. HPLC was used to determine the concentration of FA in vivo with salicylic acid as internal standard. The results of body distribution indicated that RGD-coated liposomes could be mediated into the brain with a 6-fold FA concentration compared to FA solution and 3-fold in comparison to uncoated liposome. Brain targeted delivery was achieved and a reduction in dosage might be allowed.

Cytokine and Chemokine Gene Expression of IL‐1β Stimulated Equine Articular Chondrocytes

To evaluate mRNA expression of several proinflammatory and anti-inflammatory cytokines and chemokines in equine unstimulated and interleukin-1beta (IL-1beta)-stimulated chondrocytes. In vitro experiment using equine chondrocyte cultures. Whole articular cartilage from metacarpophalangeal joints (n=5 horses; 10 fetlocks). Chondrocyte monolayer cultures were established from digested adult equine articular cartilage and stimulated with 5 ng/mL of recombinant human IL-1beta. RNA was extracted from the cells 24 hours after stimulation. IL-1beta, IL-4, IL-6, IL-8, tumor necrosis factor-alpha (TNF-alpha), and ubiquitin (house keeping gene) mRNA expression were investigated by real-time RT-PCR. IL-1beta, IL-6, and IL-8 mRNA were expressed in unstimulated chondrocytes from macroscopically normal joints and were significantly up-regulated after stimulation (5/5 horses). IL-4 mRNA was not detected in any samples (0/5 horses). TNF-alpha mRNA, by comparison, was expressed in 2/5 unstimulated samples and in all stimulated samples but a considerable sample variation in response to IL-1beta stimulation was observed. Equine chondrocytes express mRNA for several proinflammatory cytokines and chemokines and IL-1beta modulates their expression. Chondrocytes express proinflammatory cytokines and chemokines capable of modulating a local inflammatory cascade in articular cartilage, which could potentially lead to focal degradation and osteoarthritis.

Microsomal prostaglandin E synthase-1, which is not coupled to a particular cyclooxygenase isoenzyme, is essential for prostaglandin E(2) biosynthesis in vascular smooth muscle cells.

Prostaglandin (PG) E(2) induces expression of matrix metalloproteinases and angiogenic factors, thereby contributing to plaque instability. To study the influence of cyclooxygenase (COX) and PGE synthase (PGES) isoenzyme expression on PGE(2) and PGI(2) biosynthesis in vascular smooth muscle cells (VSMC) in culture. Cells were treated with human recombinant IL-1beta over different periods of time. Expression of PGI synthase, and COX and PGES isoenzymes was determined by real-time reverse transcriptase polymerase chain reaction and immunoblotting. Biosynthesis of prostanoids from exogenous or endogenous substrate was analyzed by high-performance liquid chromatography or enzyme-immunoassay after incubation of cells with labeled arachidonic acid or thrombin, respectively. Cytosolic PGES and microsomal PGES (mPGES) -1 and -2 were expressed in VSMC. PGES activity was mainly linked to mPGES-1. IL-1beta induced COX-2 and mPGES-1 with a different time course. VSMC ability to synthesize PGE(2) and PGI(2) fitted mPGES-1 and COX-2 expression, respectively. The ability of VSMC to produce PGI(2) was downregulated by mPGES-1 expression and was restored when mPGES-1 expression was silenced. Results from COX-1 and COX-2 silencing and selective inhibition showed that both COX-1 and COX-2 were involved in the biosynthesis of PGE(2) and their relative contribution depended on the time of incubation with IL-1beta. mPGES-1 is the main PGES responsible for PGE(2) biosynthesis by VSMC and its induction downregulates VSMC ability to produce PGI(2.) These results support the concept that under inflammatory conditions VSMC could significantly contribute to plaque instability and that mPGES-1 may be a target for therapeutic intervention in patients with cardiovascular risk.

Structural differences between the putative carbohydrate-recognition domains of human IL-1 alpha, IL-1 beta and IL-1 receptor antagonist obtained by in silico modeling

In a previous report (Cebo et al. J Biol Chem 276 (2001) 5685-5691), it was established that biologically active recombinant human IL-1alpha and IL-1beta had different carbohydrate-binding properties. IL-1alpha recognized a di-antennary N-glycan with two alpha2-3-linked sialic acid residues, whereas IL-1beta recognized the GM(4), a alpha2-3-linked sialylated glycosphingolipid. These different carbohydrate-binding properties of two interleukins binding to the same receptor (IL-1R) could explain why these molecules had different biological effects and cell specificities. Molecular modeling of the ligands and in silico docking experiments defined putative carbohydrate-recognition domains localized in the same area of the two molecules, a domain different from that defined as the type I IL-1R binding domain. The calculated pattern of hydrogen bonding and of van der Waals interactions fulfilled the essential features observed for calcium-independent lectins (mammalian, viral or bacterial). The analysis of the same domain of the third members of this family of molecules, the IL-1R-antagonist, indicated it did not fulfill the criteria for carbohydrate-recognition domains. It is proposed that its role as a pure antagonist is due to the absence of lectin activity and consequently explained its inability to associate IL-1R with other surface molecular complexes necessary for signaling.

A new inducible adenoviral expression system that responds to inflammatory stimuli in vivo

Gene transfer using inducible promoters, which control expression of transgenic proteins in response to physiological conditions, may have significant advantages. In this study, we tried to achieve an inducible adenoviral expression system for physiologically responsive gene therapy of autoimmune or inflammatory diseases. A luciferase reporter vector with a hybrid promoter containing the human IL-1beta enhancer region (-3690 to - 2720) and the human CIITA promoter IV (-399 to + 2) was constructed. A replication-deficient adenovirus was engineered with luciferase controlled by the IL1beta/CIITApIV promoter (Ad-IL1beta/CIITApIV-Luc). The reporter vector or adenovirus was transfected to C57Bl/6 myeloid dendritic cells (DCs), RAW264.7, and Hep G2 to study the in vitro characteristics of this hybrid promoter. An inflammation model was prepared by injecting lipopolysaccharide (LPS) into Balb/c mice intraperitoneally (i.p.), and infected with Ad-IL1beta/CIITApIV-Luc or Ad-CMV-Luc to study the in vivo characteristics of the IL1beta/CIITApIV promoter. The IL1beta/CIITApIV hybrid promoter has pronounced promoter activity, broad-range responsiveness to cytokines or LPS, and can be rechallenged after first induction. In the inflammation model, IL1beta/CIITApIV could drive hepatic luciferase expression increasedly rapidly after LPS challenge and in a LPS dose-dependent manner. Using the IL1beta/CIITApIV hybrid promoter in gene transfer vectors may make it possible to produce transgenic proteins in vivo in direct relationship with the intensity and duration of an individual's status. By providing endogenously controlled production of transgenic proteins, this approach might limit the severity of autoimmune or inflammatory response without interfering with the beneficial components of host defense and immunity.