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Abstract Although inflammation is emerging as a candidate risk factor in tumorigenesis of nasopharyngeal carcinoma (NPC). In particular, Interleukin (IL) 13 involved inflammatory diseases and cancers. Single nucleotide polymorphisms in IL-13 have been associated with multiple cancers. The study analyzed genetic polymorphisms in IL-13 aiming to investigate its' potential susceptibility with the NPC. The genotyping of polymorphisms (rs20541, rs1295687 and rs2069744) was examined by Snapshot SNP and DNA sequencing. All SNPs were within Hardy-Weinberg equilibrium and each appeared in three genotypes in NPC and controls. Adjusted logistic regression showed that the TT genotype of rs20541 increased the risk of lymph node metastasis (TT vs. CC: OR = 2.87, 95%CI, 1.33–6.18, P = 0.007). CT/CC genotypes were associated with the decreased the risk of lymph node metastasis in NPC (CT/CC vs. TT: OR = 0.32, 95%CI, 0.16–0.65, P = 0.002). The concentration of IL-13 was significantly elevated in NPC patients compared with controls (P = 0.012). Moreover, significant differences were detected in the T-C-T haplotype distribution between NPC patients and controls (OR = 2.47, 95%CI, 1.06–5.78, P = 0.031). Our results, the first report, provide evidence that rs20541 polymorphisms may affect the lymph node metastasis of NPC patients in Chinese population. [ABSTRACT FROM AUTHOR]

Interleukin (IL) 13 plays a critical role in inflammatory diseases, including systemic lupus erythematosus (SLE). This study aims to explore the potential association of IL-13 polymorphisms with the risk of SLE. We genotyped IL-13 rs20541, rs848 and rs1295686 using Snapshot SNP genotyping assays. Plasma IL-13 level was determined by enzyme-linked immunosorbent assay (ELISA). We found that rs20541 was associated with increased risk of SLE (CT vs. CC: adjusted OR = 1.43, 95%CI, 1.04–1.99, P = .030; TT vs. CC: adjusted OR = 1.73, 95%CI, 1.10–2.73, P = .018; CT/TT vs. CC: adjusted OR = 1.50, 95%CI, 1.10–2.04, P = .010; T vs. C adjusted OR = 1.34, 95%CI, 1.08–1.93, P = .031). CT and TT genotypes in rs20541 were associated with increased risk of renal disorder in SLE (CT vs. CC: adjusted OR = 1.97, 95%CI, 1.18–3.28, P = .009; TT vs. CC: adjusted OR=2.42, 95%CI, 1.22–4.77, P = .011). Moreover, The concentration of IL-13 was significantly elevated in rs20541 CT/TT genotypes compared with CC genotype ( P < .001). These results suggest that rs20541 CT/TT genotypes may be a risk factor for SLE, probably by increasing the level of IL-13. [ABSTRACT FROM AUTHOR]

We investigated whether IL-33 is involved in mucus overproduction and goblet cell hyperplasia in eosinophilic chronic rhinosinusitis (ECRS). IL-33 mRNA was significantly higher in the eosinophilic CRS group than in the non-eosinophilic CRS group from human nasal polyps. IL-33 induced MUC5AC mRNA and MUC5AC protein, and also goblet cell hyperplasia at air liquid interface culture in human nasal epithelial cells. In addition to that, IL-33 induced MUC5B and FOXA3 , and reduces FOXJ mRNA. In conclusion, our present study demonstrated that the direct evidence of IL-33 which lead to increase mucin gene and protein expression, as well as goblet cell hyperplasia. This study provides novel insights into the role of IL-33 on mucus overproduction in eosinophilic inflammation of human airways. [ABSTRACT FROM AUTHOR]

• In neutrophils, IL-4 is more potent inducer of Stat6 activation than IL-13. • IFN-γ and IL-4/IL-13 regulate distinct gene expression in neutrophils. • IL-4/IL-13 induced genes are linked to MHCII biosynthesis oxygen or LPS responses. • IFN-γ-induced genes are related to intracellular infections. • Subjecting neutrophils to IL-4 decreases their anaerobic glycolysis. Interleukin (IL)-4 and IL-13 are related cytokines with well-known specific roles in type 2 immune response. However, their effects on neutrophils are not completely understood. For this, we studied human primary neutrophil responses to IL-4 and IL-13. Neutrophils are dose-dependently responsive to both IL-4 and IL-13 as indicated by signal transducer and activator of transcription 6 (STAT6) phosphorylation upon stimulation, with IL-4 being more potent inducer of STAT6. IL-4-, IL-13- and Interferon (IFN)-γ-stimulated gene expression in highly purified human neutrophils induced both overlapping and unique gene expression in highly purified human neutrophils. IL-4 and IL-13 specifically regulate several immune-related genes, including IL-10, tumor necrosis factor (TNF) and leukemia inhibitory factor (LIF), while type1 immune response-related IFN-γ induced gene expression related for example, to intracellular infections. In analysis of neutrophil metabolic responses, oxygen independent glycolysis was specifically regulated by IL-4, but not by IL-13 or IFN-γ, suggesting specific role for type I IL-4 receptor in this process. Our results provide a comprehensive analysis of IL-4, IL-13 and IFN-γ -induced gene expression in neutrophils while also addressing cytokine-mediated metabolic changes in neutrophils. [ABSTRACT FROM AUTHOR]

Type 2 (T2) asthma is characterized by airflow limitations and elevated levels of blood and sputum eosinophils, fractional exhaled nitric oxide, IgE, and periostin. While eosinophils are associated with exacerbations, the contribution of eosinophils to lung inflammation, remodeling and function remains largely hypothetical. To determine the effect of T2 cytokines IL-4, IL-13 and IL-5 on eosinophil biology and compare the impact of depleting just eosinophils versus inhibiting all aspects of T2 inflammation on airway inflammation. Human eosinophils or endothelial cells stimulated with IL-4, IL-13 or IL-5 were assessed for gene changes or chemokine release. Mice exposed to house dust mite extract received anti-IL-4Rα (dupilumab), anti-IL-5 or control antibodies and were assessed for changes in lung histological and inflammatory endpoints. IL-4 or IL-13 stimulation of human eosinophils and endothelial cells induced gene expression changes related to granulocyte migration; whereas, IL-5 induced changes reflecting granulocyte differentiation. In a mouse model, blocking IL-4Rα improved lung function by impacting multiple effectors of inflammation and remodeling, except peripheral eosinophil counts, thereby disconnecting blood eosinophils from airway inflammation, remodeling and function. Blocking IL-5 globally reduced eosinophil counts but did not impact inflammatory or functional measures of lung pathology. Whole lung transcriptome analysis revealed that IL-5 or IL-4Rα blockade impacted eosinophil associated genes, whereas IL-4Rα blockade also impacted genes associated with multiple cells, cytokines and chemokines, mucus production, cell:cell adhesion and vascular permeability. Eosinophils are not the sole contributor to asthma pathophysiology or lung function decline and emphasizes the need to block additional mediators to modify lung inflammation and impact lung function. [ABSTRACT FROM AUTHOR]

Background There is need for prognostic markers for symptomatic food allergy since current diagnostic methods are insufficient and/or time and labor consuming. Objective To estimate the cytokine mRNA profiles in peripheral blood mononuclear cells (PBMC) before and after a double-blind placebo-controlled food challenge series in schoolchildren with suspected allergy to milk, egg or cod and in healthy controls. Analyses of fecal inflammatory biomarkers before and after the challenge were included. Methods Twelve-year-old children from a population-based cohort reporting complete avoidance of milk, egg, cod or wheat due to perceived hypersensitivity were clinically examined and those with suspected food allergy were evaluated with a 3-session double-blind placebo-controlled food challenge (n = 18). Seven healthy controls participated in a double-blind challenge with egg. Before and after the challenge series, the cytokine mRNA expression was quantified for 13 cytokines discriminating between humoral Th2-, cytotoxic Th1-, regulatory Th3/Tr1- and inflammatory responses. Fecal calprotectin and eosinophil-derived neurotoxin (EDN) were also analyzed in children with suspected food allergy before and after the challenge series. Results Pre challenge, children with suspected food allergy had higher IL-13 and TNF-α expression and lower IFN-γ and IL-15 expression compared to healthy controls (all p < 0.05). Children with challenge-proven food allergy had increased IL13 and IL-10 expression compared to the levels seen in negative challenges (p < 0.05). Post challenge, IL-1β and IL-6 mRNA levels were elevated in the food allergic children compared to controls (p < 0.05). Fecal calprotectin and EDN levels were higher in challenge-proven food allergy compared to a negative challenge although not statistically significantly. Conclusion & clinical relevance Increased baseline mRNA levels of the Th2-related cytokine IL-13 and the regulatory cytokine IL-10 predicted a positive food challenge outcome. These cytokines in combination with fecal calprotectin and EDN might serve as future prognostic markers for symptomatic, IgE-mediated food allergy but need further validation in a larger patient cohort. [ABSTRACT FROM AUTHOR]

IL-4 was identified as the first cytokine to be produced by mast cells and is responsible for promoting mast cell IL-13 production. IL-4 and IL-13 play a prominent role in stimulating and maintaining the allergic response. As closely related genes, IL-4 and IL-13 share a common receptor subunit, IL-4Rα, necessary for signaling. Here we summarize the literature on mast cell activation associated with IL-4 and IL-13 production, including downstream signaling. We also describe the positive and negative roles each cytokine plays in mast cell immunity and detail the differences that exist between mouse and human mast cell responses to IL-4 and IL-13. [ABSTRACT FROM AUTHOR]

Aberrant production of the prototypical type 2 cytokines, interleukin (IL)-4 and IL-13 has long been associated with the pathogenesis of allergic disorders. Despite tremendous scientific inquiry, the similarities in their structure, and receptor usage have made it difficult to ascertain the distinct role that these two look-alike cytokines play in the onset and perpetuation of allergic inflammation. However, recent discoveries of differences in receptor distribution, utilization/assembly and affinity between IL-4 and IL-13, along with the discovery of unique innate lymphoid 2 cells (ILC2) which preferentially produce IL-13, not IL-4, are beginning to shed light on these mysteries. The purpose of this chapter is to review our current understanding of the distinct roles that IL-4 and IL-13 play in allergic inflammatory states and the utility of their modulation as potential therapeutic strategies for the treatment of allergic disorders. [ABSTRACT FROM AUTHOR]

Protective immunity against enteric parasitic nematodes is dependent on IL-4, IL-13 activation of their exclusive transcription factor STAT6. The precise pathways by which enteric parasitic nematodes are recognized by the host is unclear, but elimination of this important interaction in developed nations is thought to contribute to the dysregulated immune responses that are a characteristic of autoimmune diseases. Nematode-derived products are involved in evading host defenses to promote their life cycle leading to modulation of host immune responses. Host protective immunity has adapted to enteric parasitic nematode infection by elaboration of mucins, increasing intraluminal fluid to control access to the surface epithelium, increasing cell turnover to maintain an effective barrier to their invasion, initiating immune responses through activation of resident immune cells, and recruitment of additional immune cells to release immune mediators that help orchestrate these responses. Both the immune and functional outcomes depend largely on IL-4/IL-13 signaling through STAT6, with a dominant role for IL-13 working through the type 2 IL-4 receptor (IL-4R). The recent observation that enteric nematode infection prevents the onset of a number of experimental models of IBD, diabetes, and several extraintestinal autoimmune diseases including multiple sclerosis has generated considerable interest in the identification of worm/egg products involved in the generation and maintenance of Th2 cytokines that may mediate the beneficial effects of nematode infection in autoimmune and inflammatory pathologies. [ABSTRACT FROM AUTHOR]

Elevated levels of the cytokine IL-13 has been found to be associated with autoimmune diseases, including Sjögren's Syndrome. However, whether IL-13 plays a causative role in disease development is not known and cannot be easily studied in humans. Our previous work has shown that levels of IL-13 are elevated in Id3 knockout mice, which has been established as a model for primary Sjögren's Syndrome. Here, we utilized an IL-13 reporter to determine the source of the elevated IL-13 levels observed in Id3 knockout mice and assess its contribution to SS pathology. Our results indicate that T cells, notably CD4 and γδ T cells, in Id3 knockout mice acquire IL-13 competency at an elevated rate well before disease symptoms become apparent. We also show that T cells developing early in life are more predisposed to produce IL-13. Finally, analysis of Id3 and IL-13 double deficient mice demonstrated that IL-13 plays an essential role in the deterioration of gland function. Our study provides crucial genetic evidence that enhanced IL-13 production by T cells can play a causative role in the exocrinopathy observed in Id3 knockout mice. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Type 1 diabetes and latent autoimmune diabetes in adults (LADA) are thought to result from immune-mediated β-cell destruction. It remains unclear why LADA is clinically less severe compared to type 1 diabetes. This study aimed to compare the pro-inflammatory (interferon-γ, IFN-γ) and anti-inflammatory (interleukin-13, IL-13) T-cell responses in humans with LADA and type 1 diabetes. Research design and methods: IFN-γ and IL-13 T-cell responses to a panel of 16 (auto)-antigens were tested using an enzyme linked immune-spot technique and peripheral T-cells from 35 patients with type 1 diabetes, 59 patients with type 2 diabetes, 23 LADA patients, and 42 control subjects. Results: LADA and type 1 diabetes patients did not display any statistically significant differences in the frequency of IFN-γ or IL-13 responses to auto-antigenic stimuli, positive control or mitogen. Overall very low T cell reactivity to autoantigens was detected in all groups. IL-13 responses but not IFN-γ responses to recall antigen tetanus toxoid were higher in healthy control subjects compared to patients with type 1 or type 2 diabetes or LADA (P <0.05). Diabetes, independent of type, was associated with weaker response to recall antigen tetanus toxoid. Conclusions: LADA patients are indistinguishable from type 1 diabetes patients for cellular IFN-γ and IL-13 responses upon mitogen and recall antigen stimulation. These results extend previous findings showing that systemic cytokine/chemokine and humoral responses in type 1 diabetes and LADA are similar. [Copyright &y& Elsevier]

Abstract: Systemic sclerosis (SSc) has the highest fatality rate among connective tissue diseases and is characterized by vascular damage, inflammation and fibrosis. Currently, no therapy has proven effective in modifying the course of SSc, a reflection of its complex pathogenesis. T cell-derived cytokines have been implicated in the induction of fibrosis. The role of the pro-fibrotic type 2 cytokine IL-13 and its regulation appear to be important in the pathogenesis of SSc and other fibrotic disorders. Recent work has shown that dysregulated production of IL-13 by effector CD8+ T cells is critical for predisposing patients to more severe forms of cutaneous disease and that this dysregulation is associated with defects in the molecular control of IL-13 production, such as increased expression of the transcription factor GATA-3. Silencing of GATA-3 with siRNA significantly reduces IL-13 production by CD8+ T cells from patients. We review these new insights into SSc pathogenesis that will enable establishment of highly relevant biomarkers of immune dysfunction in patients predisposed to develop SSc and open new possibilities for development of more specific diagnosis and treatment. [Copyright &y& Elsevier]

Abstract: RANTES is a potent chemoattractant for various important inflammatory cells such as eosinophils, memory T cells and mast cells. It has been long recognized as a crucial player in the pathogenesis of allergy. However, little is known of its effects on cytokine secretion and protease activated receptor (PAR) expression in mast cells. In the present study, we examined potential influence of RANTES on IL-13 and IL-12 release from P815 cells and PAR expression on P815 cells by using flow cytometry analysis, quantitative real-time PCR, ELISA and cellular activation of signaling ELISA (CASE) techniques. The results showed that RANTES induced up to 2.2-fold increase in IL-13, but not IL-12 release from P815 cells. Blocking antibodies against RANTES and CCR5 diminished RANTES induced IL-13 release. Furthermore, RANTES upregulated expression of PAR-1, PAR-2 and PAR-3 mRNAs, but enhanced only PAR-1 protein expression. At 1ng/ml, RANTES can abolish tryptase induced IL-13 release, but enhance trypsin, tryptase and thrombin induced PAR-1, -2 and -4 expression. LY204002 abolished RANTES induced IL-13 release, indicating an Akt cell signaling pathway may be involved in the event. In conclusion, RANTES can stimulate IL-13 release from mast cells through a CCR5 and Akt cell signaling pathway dependent mechanism. It can also enhance trypsin, tryptase and thrombin-induced expression of PARs in mast cells. RANTES may contribute to modulation of IL-13 production and PAR expression in mast cells, through which participates in the mast cell related inflammation. [ABSTRACT FROM AUTHOR]

Abstract: Interleukin (IL)-6 is a multifunctional cytokine which has been showed to induce up-regulated expression of Fc epsilon RI receptor and histamine production in mast cells. However, little is known of its effects on Th2 cytokine secretion and protease activated receptor (PAR) expression in mast cells. In the present study, we examined potential influence of IL-6 on IL-13, IL-4 and IL-10 release from P815 cells and PAR expression on P815 cells by using flow cytometry analysis, quantitative real-time PCR, ELISA and cellular activation of signaling ELISA (CASE) techniques. The results showed that IL-6 induced up to 1.8-fold increase in IL-13, but not IL-4 or IL-10 release from P815 cells, and FSLLRY-NH2 did not affect IL-6 induced IL-13 release. Tryptase elicited 2.0-fold increase in IL-13 release from P815 cells, which can be inhibited by IL-6. IL-6 elicited the up-regulated expression of PAR-1, PAR-2, PAR-3 and PAR-4 mRNAs, but had little effects on expression of PAR proteins. U0126, PD98059 and LY204002 abolished IL-6 induced IL-13 release when they were preincubated with P815 cells, indicating ERK and Akt cell signaling pathways may be involved in the event. In conclusion, IL-6 can stimulate IL-13 release from mast cells through an ERK and Akt cell signaling pathway dependent, but PAR independent mechanism. [Copyright &y& Elsevier]

Abstract: Smoking is a strong risk factor for periodontitis. Treated patients who smoke show increased risk for further periodontal breakdown, despite receiving maintenance care. Previous work indicated that such patients have a monocytic cytokine response favoring Th2 activity. The purpose of this study was to investigate the T lymphocytic cytokine production representing Th1 and Th2 subpopulations in smokers and non-smokers. Venous blood was collected from 30 treated periodontitis patients (12 smokers) and 24 healthy subjects (12 smokers). Whole blood cell cultures were stimulated and interferon (IFN)-γ and interleukin (IL)-13 were measured in the culture supernatants, representing types 1 and 2 Th subpopulations, respectively. Unadjusted data showed that smokers had more lymphocytes, and higher levels of IFN-γ and IL-13, irrespective of being periodontal patient. However in a multivariate analysis, increased IFN-γ production was not significantly explained by smoking, while higher IL-13 was strongly explained by smoking (21%, p <0.001). We suggest that the increased Th activity and specifically an elevated Th2 profile in smokers may constitute a risk for smoking patients which may induce conversion of periodontal stability into progressive disease. This phenomenon may be equally important in other conditions, where connective tissue and bone loss are hallmarks of disease pathophysiology. [Copyright &y& Elsevier]

Abstract: IL-13 is known to affect many processes that contribute to an asthmatic phenotype, including inflammation, fibrosis, and mucus production. Members of the aquaporin (AQP) family of transmembrane water channels are targets of regulation in models of lung injury and inflammation. Therefore, we examined AQP mRNA and protein expression in allergen and IL-13-induced mouse models of asthma. Lungs from ovalbumin sensitized and ovalbumin challenged (OVA/OVA) and IL-13 treated mice showed airway thickening, increased mucus production, and pulmonary eosinophilia. Pulmonary function tests showed a significant increase in methacholine-induced airway hyperreactivity in OVA/OVA and IL-13-treated mice as compared with controls. Quantitative PCR analysis revealed differential regulation of AQPs in these two models. AQP1 and AQP4 mRNA expression was downregulated in the OVA/OVA model, but not in the IL-13 model. AQP5 mRNA was reduced in both models, whereas AQP3 was upregulated only in the IL-13 model. Western analysis showed that diminished expression of an apically localized aquaporin, (AQP5), and concomitant upregulation of a basolateral aquaporin (AQP3 or AQP4) are characteristic features of both inducible asthma models. These results demonstrate that aquaporins are common targets of gene expression in both allergen and IL-13 induced mouse models of asthma. [Copyright &y& Elsevier]

Abstract: Background and purpose: Interleukin-13 (IL-13), a major Th2 cytokine, plays an important role in bronchial asthma, including mucus production, inflammation and airway hyperresponsiveness. Although IL-13 through its binding to IL-4 receptor α (IL-4Rα/IL-13Rα1 uses the canonical signal transducer and activator of transcription 6 (STAT6)-signaling pathway to mediate these tissue responses, recent studies have demonstrated that other signaling pathways may also be involved in. In the present study, whether IL-13 induces an activation of nuclear factor (NF)-κB, inflammatory transcription factor, was investigated in human bronchial smooth muscle cells (hBSMCs). Methods: Nuclear proteins were extracted from cultured hBSMCs treated with tumor necrosis factor (TNF)-α (10ng/mL) or IL-13 (100ng/mL), and assayed for activated NF-κB and STAT6 by Western blotting. Result: Treatments with TNF-α and IL-13 induced a translocation of NF-κB to nuclei in hBSMCs. In addition, coincubation with BMS-345541 (0.3μM), an inhibitor of NF-κB (IκB) kinase (IKK) inhibitor, markedly inhibited the translocation of NF-κB. Conclusion: Our results suggest for the first time that IL-13 activates NF-κB in hBSMCs. [Copyright &y& Elsevier]

Abstract: Treatment of Nylon wool-passed cells (NWC) prepared from the spleen of C57BL/6 mice with IL-18 and IL-12, but not with IL-18 alone, resulted in induction of IFN-γ, a Th1 cytokine, and GM-CSF at 24h, and IL-13, a Th2 cytokine at 72h. The induction of IL-13 was suppressed by anti-GM-CSF antibody, indicating involvement of GM-CSF in IL-13 production. When NWC incubated with IL-18 and IL-12 for 72h (“primary treatment”) were treated again with the same cytokines (“secondary treatment”), IL-13 was induced much more quickly than observed in the primary treatment. Flow cytometric analysis of NWC after the primary treatment showed marked increases in the CD4(−)CD8(−) non-T cell population bearing CD25(+), CD45RB(super high) and CD122(+). These cells were positive for CD49b but negative for NK1.1, indicating that they were not typical but NK-like cells. The NK-like cells produced IL-13 in response to the treatment with IL-18 alone, indicating that the generation of these cells in the primary treatment likely accounts for the quick production of IL-13 in the secondary treatment. These results show that IL-18 and IL-12 generates the NK-like cells in NWC by a process mediated by GM-CSF that are ready for producing IL-13. [Copyright &y& Elsevier]

Abstract: 4-1BB, one of co-stimulatory molecules, is a member of TNF receptor superfamily and expressed on T cells upon TCR ligation. We have shown that 4-1BB is a co-stimulatory molecule enhancing cell cycle progression and inhibiting activation-induced cell death of CD8+ T cells by enhancing TCR signaling pathways. Here, we first report that the cross-linking of 4-1BB increased the expression of IL-13 mRNA and protein, and its secretion apparently via calcineurin, a Ca2+/calmodulin-dependent phosphatase. Ligation of 4-1BB with p815-m-4-1BBL evoked intracellular Ca2+ level in CD8+ T cells. CD8+ T cells express IL-13 receptor α1 mRNA. Incubation with anti-IL-13 blocking mAb reduced proliferation of CD8+ T cells enhanced by 4-1BB, and the treatment of CD3/4-1BB-ligated CD8+ T cells with recombinant IL-13 enhances cell proliferation, indicating that 4-1BB-induced IL-13 expression is partially responsible for the CD8+ T cell expansion in an autocrine or paracrine manner. [Copyright &y& Elsevier]

Abstract: Although routinely used in clinical practice, skin prick tests and serum specific IgE often fail to distinguish between IgE-sensitization and symptomatic IgE-mediated allergy. There is therefore a need for new laboratory tests relating allergic symptoms to the offending agent. In this way, we evaluated the diagnostic reliability of a new whole blood quantitative real-time PCR assay for IL-4 and IL-13 mRNAs. We compared the response of cat allergic patients and non-cat allergic controls upon anti-IgE and cat allergen (Fel d1) stimulation of whole blood. Allergen addition led to a significant increase of IL-4 and IL-13 mRNAs in allergic patients compared to non-allergic controls (p &#60;0.0001). Both cytokine mRNA levels were strongly correlated and peaked within 2h after Fel d1 or anti-IgE addition. This rapid increase as well as purification experiments led us to the conclusion that basophils represent an important if not the main source of both transcripts in this setting. The effect was allergen-specific since not observed when stimulating blood from cat allergic patients with birch pollen. Interestingly, we found that IFN-γ mRNA, contrary to IL-4 mRNA, reached higher levels in response to Fel d1 with control individuals than with patients allergic to cat. This study shows that whole blood real-time PCR is a valuable method for IL-4 and IL-13 mRNA measurement after in vitro allergen challenge. We suggest that it might be useful, complementing conventional markers, for the diagnosis and the follow-up of allergic diseases. Further assessments are required to evaluate the clinical potential of this technique. [Copyright &y& Elsevier]

Abstract: We investigated the effects of the Th2-like cytokines IL-4 and IL-13 and of IL-10 on the induction of iNOS and NO production in rat eosinophils. Addition of mIL-4 to the eosinophil culture increased iNOS activity and nitrite production but did not improve the stimulatory effect of IFN-γ and LPS. In contrast to eosinophils, addition of mIL-4 to macrophage cultures inhibited the iNOS expression and nitrite production induced by IFN-γ plus LPS. Addition of mIL-13 to the eosinophil cultures did not significantly change iNOS activity and nitrite production in cells stimulated or not with IFN-γ plus LPS. On the other hand, IL-13 inhibited iNOS activity in IFN-γ plus LPS-stimulated macrophages. In the presence of IL-10, iNOS activity in non-stimulated eosinophil or macrophage cultures was not significantly altered, but the enzyme expression was inhibited in IFN-γ plus LPS-stimulated eosinophils or macrophages. The production of nitrite by eosinophils stimulated by IFN-γ plus LPS was inhibited by the presence of IL-10 in the medium. In conclusion, eosinophils might exhibit differential modulation of the l-arginine/iNOS pathway depending on the profile of Th2 cytokines produced during allergic diseases. IL-4 appears to be an important Th2 cytokine involved in the induction of the l-arginine/iNOS pathway in eosinophils. [Copyright &y& Elsevier]

Abstract: Asthma is a chronic inflammatory disease characterized by reversible bronchial constriction, pulmonary inflammation and airway remodeling. Current standard therapies for asthma provide symptomatic control but fail to target the underlying disease pathology. Furthermore, no therapeutic agent is effective in preventing airway remodeling. Interleukin 13 (IL-13) is a pleiotropic cytokine produced mainly by T cells. A substantial amount of evidence suggests that IL-13 plays a critical role in the pathogenesis of asthma. Therefore, a neutralizing anti-IL-13 monoclonal antibody could provide therapeutic benefits to asthmatic patients. To test the concept we have generated a neutralizing rat anti-mouse IL-13 monoclonal antibody, and evaluated its effects in a chronic mouse model of asthma. Chronic asthma-like response was induced in ovalbumin (OVA) sensitized mice by repeated intranasal OVA challenges. After weeks of challenge, mice developed airway hyperresponsiveness (AHR) to methacholine stimulation, severe airway inflammation, hyper mucus production, and subepithelial fibrosis. When given at the time of each intranasal OVA challenge, anti-IL-13 antibody significantly suppressed AHR, eosinophil infiltration, proinflammatory cytokine/chemokine production, serum IgE, and most interestingly, airway remodeling. Taken together, these results strongly suggest that a neutralizing anti-human IL-13 monoclonal antibody could be an effective therapeutic agent for asthma. [Copyright &y& Elsevier]

: BackgroundIL-18 is a pleiotropic cytokine involved in the polarisation of T-cell response. This study was performed to determine whether or not IL-18 is detectable in phytohemagglutinin (PHA) or betalactoglobulin (BLG) stimulated supernatants of cord blood mononuclear cells (CBMC) and to study the in vitro effect of IL-18 on the interferon (IFN)-γ and IL-13 release of CBMC of healthy neonates.: MethodsCBMC of neonates were isolated by Ficoll density centrifugation. The cytokines IFN-γ, IL-13 and IL-18 in the cell culture supernatants were measured using the ELISA technique following stimulation with a unspecific (PHA 20 μg/ml) and an allergen-specific stimulus (BLG 25 μg/ml). In order to study the in vitro effect of IL-18, CBMC were stimulated either with medium alone or with IL-18, IL-18 + PHA and IL-18 + BLG.: ResultsIL-18 levels in supernatants of CBMC were low and did not vary significantly between unstimulated and PHA or BLG stimulated cell cultures (median 21.4; 23.5 and 15.5 pg/ml, respectively). IFN-γ and IL-13 levels were significantly higher in response to PHA and BLG (PHA: IFN-γ, 6154; IL-13, 4357; BLG: IFN-γ, 801; IL-13, 249 pg/ml) compared to unstimulated cell cultures. The addition of IL-18 to PHA or BLG stimulated CBMC significantly enhanced the IFN-γ release (PHA: 6154; PHA + IL-18: 13474, p=0.0001; BLG: 801; BLG + IL-18: 1077, p=0.008). In comparison to incubation without IL-18, the release of IL-13 was invariable or even reduced, when CBMC were stimulated with PHA + IL-18 (4026, p=0.16) or BLG + IL-18 (124, p=0.0001) compared to stimulation of CBMC with PHA (4357 pg/ml) or BLG (249 pg/ml) alone.: ConclusionsIL-18 is detectable in supernatants of CBMC. We observed a significant effect of IL-18 + PHA as well as IL-18 + BLG on IFN-γ release in vitro. Based on our findings we conclude that IL-18 could act as a strong TH1-inducing factor on stimulated CBMC also in vivo. [Copyright &y& Elsevier]

• IL-3 induced 323 genes encoding surface proteins on human basophils. • GITR was preferentially induced on basophils by IL-3. • GITR promoted secretion of histamine, IL-4 and IL-13 by IL-3-activated basophils. Human basophils regulate allergic reactions by secreting histamine, interleukin 4 (IL-4) and IL-13 through key surface receptors FcεRI as well as IL-3R, which are constitutively expressed on basophils. IL-3/IL-3R signaling axis plays key roles in regulating the development and activation of basophils. We and others have shown that IL-3-induced surface receptors e.g. ST2, IL-17RB and IL-2 receptors regulate the biology of basophils. However, the expression and function of IL-3-induced surface proteins on human basophils remain to be elucidated. We in this study aimed to identify new basophil activation regulators by transcriptomic analysis of IL-3-stimulated basophils. Gene expression microarray analysis of IL-3-treated basophils revealed 2050 differentially expressed genes, of which 323 genes encoded surface proteins including GITR. We identified that GITR was preferentially induced by IL-3 rather than anti-IgE, IL-33, fMLP and C5a. IL-3-induced GITR was suppressed by inhibitors targeting JAK2, PI3K and MEK1/2. Stimulation of IL-3-treated basophils by GITR enhanced the expression of IL-4 and IL-13. Moreover, IgE-mediated degranulation was enhanced by GITRL in the presence of IL-3. This transcriptomic analysis of IL-3-activated basophils helps to identify novel activation regulator. IL-3-induced GITR promoted the activation of basophils, adding new evidence supporting GITR as an important player in Th2-associated immune responses. [ABSTRACT FROM AUTHOR]

• A type-2 immune response contributes to the pathogenesis of systemic sclerosis. • IL-4 and IL-13 contribute to inflammation and fibrosis in systemic sclerosis. • IL-4 and IL-13 may be therapeutic targets for the treatment of systemic sclerosis. Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of skin and internal organs. Its pathogenesis, which is still poorly understood, features three main pathogenic moments: an initial diffuse vasculopathy followed by low-grade inflammation and a subsequent tissue fibrosis. Numerous evidences support the role of a Th2-oriented immune response during both the inflammatory and the fibrotic phase of SSc. Levels of IL-4, IL-13 and CXCL4 are higher in the serum of SSc patients compared to healthy controls. Fibrotic tissue in SSc displays a Th2 polarized CD4+ cell infiltration, influencing fibroblast phenotype and inducing collagen and extra cellular matrix protein synthesis. In tight skin mice the administration of neutralizing anti-IL-4 antibodies prevents the development of dermal fibrosis. Back-crossing these mice onto a genetic background that cannot respond to IL-4 prevents skin sclerosis. In SSc, CD8+ T lymphocytes secrete IL-13 and mediate dermal fibrosis and have skin-homing receptors. Incubation with healthy dermal fibroblasts results in elevation of extracellular matrix, which can be reduced with anti-IL13 antibodies. Specifically, IL-4 and IL-13 take part in the inflammatory phase, contribute to the transition from the inflammatory to the fibrotic phase and maintain a profibrotic state in affected organs, mediating the interaction between T cells and fibroblasts. Blocking the cross-talk between these cell types by acting on the soluble cytokines, on their receptors on cell surfaces or on intracellular signaling pathways could constitute a new therapeutic approach. [ABSTRACT FROM AUTHOR]