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Immunoglobulin E (immunoglobulin + e)
Kinds of Immunoglobulin E Terms modified by Immunoglobulin E Selected AbstractsIgE in the human placenta: why there?ALLERGY, Issue 5 2010E. Rindsjö To cite this article: Rindsjö E, Joerink M, Papadogiannakis N, Scheynius A. IgE in the human placenta: why there? Allergy 2010; 65: 554,560. Abstract Immunoglobulin E (IgE) antibodies are key effector molecules in the allergic inflammatory response and are also involved in the protection against extracellular parasites. Allergic symptoms often develop early in life, and the intrauterine environment has been proposed to play an important role in affecting the risk of later allergy development. The placenta constitutes a selective barrier between the maternal and foetal circulation. Recently, we reported that maternal IgE antibodies are present on foetal macrophages in the villous tissue of the human placenta irrespective of maternal allergy status. This review discusses the presence of IgE antibodies in the human placenta and its possible roles in normal and pathologic pregnancy. It also deals with the relationship between placental IgE and development of allergy during childhood. A better understanding of the role of IgE in placenta could give us clues on how to prevent allergy development in the future generations. [source] Histamine H4 receptor antagonist ameliorates chronic allergic contact dermatitis induced by repeated challengeALLERGY, Issue 3 2010M. Seike To cite this article: Seike M, Furuya K, Omura M, Hamada-Watanabe K, Matsushita A, Ohtsu H. Histamine H4 receptor antagonist ameliorates chronic allergic contact dermatitis induced by repeated challenge. Allergy 2010; 65: 319,326. Abstract Background:, The present study observed effects of the histamine H4 receptor on chronic allergic contact dermatitis induced by repeated challenge in mice. Methods:, Acute contact dermatitis was induced by single epicutaneous challenge of 2,4,6-trinitro-1-chlorobenzene (TNCB) to the ear. Chronic allergic contact dermatitis was developed by repeated epicutaneous challenge using TNCB on the dorsal back skin. H4 receptor antagonist JNJ7777120 was administered to wild-type mice, while H4 receptor agonist 4-methylhistamine was administered to histidine decarboxylase (HDC) (,/,) mice that synthesized no histamine. Results:, HDC (,/,) mice did not differ phenotypically from HDC (+/+) mice, and H4 receptor antagonist/agonist did not have clinical effects in terms of acute contact dermatitis reactions. H4 receptor antagonist ameliorated skin eczematous lesions induced by repeated TNCB challenge in HDC (+/+) mice. On the contrary, H4 receptor agonist exacerbated skin lesions exclusively in HDC (,/,) mice. Application of H4 receptor agonist induced migration of mast cells and eosinophils in skin lesions, and H4 receptor antagonist suppressed these changes. H4 receptor was immunohistochemically detected on mast cells in eczematous lesions. Levels of interleukin (IL)-4, -5, and -6 in lesions were decreased, whereas levels of interferon-, and IL-12 were increased by H4 receptor antagonistic activity. Serum Immunoglobulin E levels rapidly increased with repeated challenge, but decreased with H4 receptor antagonist. Conclusion:, Because chronic allergic contact dermatitis is developed by H4 receptor stimulation, H4 receptor antagonists might represent new candidate drugs for treating chronic allergic contact dermatitis. [source] Counter regulation of the high affinity IgE receptor, Fc,RI, on human airway dendritic cells by IL-4 and IL-10ALLERGY, Issue 11 2009A. Faith Background:, Immunoglobulin E is a signalling molecule within the environment of the respiratory tract, the high affinity receptor for which, Fc,RI, is expressed by dendritic cells (DC). Little is known, however, of the expression and function of Fc,RI on DC in the human respiratory tract. Methods:, CD1c+ DC were purified from surgically resected nasal turbinates of 11 atopic and 12 nonatopic patients with chronic rhinosinusitis. Expression of Fc,RI was determined by flow cytometry. Cytokine production by DC was determined by cytometric bead array. Results:, Expression of Fc,RI was significantly elevated on respiratory tract dendritic cells (RTDC) from atopic as compared to nonatopic patients. Activation of RTDC through Fc,RI induced production of the pro-inflammatory cytokines IL-6 and TNF-,, and the anti-inflammatory cytokine IL-10. The production of IL-6 and TNF-, was elevated in atopic compared to nonatopic patients studied. Conversely IL-10 production was elevated in nonatopic patients. Concomitant activation of Fc,RI and stimulation of RTDC with IL-4 inhibited production of IL-10 by RTDC. Neutralization experiments with anti-IL-10 Ab enhanced whereas addition of exogenous IL-10 to RTDC inhibited Fc,RI-mediated inflammatory cytokine production. Conclusion:, The function of Fc,RI on RTDC from patients with rhinosinusitis is susceptible to counter regulation by IL-4 and IL-10. [source] Evidence for allergen-specific IgE of maternal origin in human placentaALLERGY, Issue 6 2009M. Joerink Background:, Immunoglobulin E (IgE) has been identified on macrophage-like cells in the villi of human placenta, irrespective of the serum IgE levels or allergy status of the mother. The origin of placental IgE is debated and it is not known if it is spontaneously produced, so-called ,natural IgE', or if it has any specificity for certain allergens. The aim of this study was to investigate if placental IgE originates from mother or child and to analyse its specificity. Methods:, Immunoglobulin E was eluted from placenta by lowering the pH. Total and allergen-specific IgEs were measured in placenta eluate, maternal and cord blood plasma by means of ImmunoCAP (Phadia AB). The levels of natural antibodies were determined with an anti-phosphorylcholine (PC) enzyme-linked immunosorbent assay, as natural IgE has been shown in one previous publication with this assay. Results:, Detectable amounts of IgE were eluted from 11/12 full-term placentas. Natural (anti-PC) IgE antibodies were detected in low amounts in maternal plasma but not in the placental eluate or in cord blood plasma. There was a significant correlation between the amount of total IgE eluted from placenta and the levels of total IgE in maternal plasma; however, not between maternal and cord blood plasma. Allergen-specific IgE was only found in placental eluates from mothers with specific IgE towards these allergens. Furthermore, there was a significant correlation between the amount of allergen-specific IgE eluted from placenta and the levels of allergen-specific IgE in maternal plasma. Allergen-specific IgE could not be detected in cord blood. Conclusion:, These results suggest a maternal origin of placental IgE, which can be allergen-specific. [source] Tomato profilin Lyc e 1: IgE cross-reactivity and allergenic potencyALLERGY, Issue 5 2004S. Westphal Background:, To date, very little data are available about the nature of tomato allergens. Immunoglobulin E (IgE) cross-reactive profilins have been suggested to account for allergic symptoms in patients suffering from tomato allergy. Methods:, The cDNA of tomato profilin was amplified by reversely transcribed polymerase chain reaction (RT-PCR) from total RNA extracted from ripe tomato fruit. The gene was cloned into the pET101D expression plasmid and the protein was produced in Escherichia coli BL21. Purification was performed via poly- l -proline (PLP) affinity chromatography. IgE reactivity of recombinant tomato profilin was investigated by immunoblot and enzyme-linked immunosorbent assay. IgE-inhibition studies were performed to analyse cross-reactivity with other profilins. To determine the allergenic activity of the recombinant protein, basophil histamine release assays using sera of patients with adverse reactions to tomato were performed. Results:, Profilin was identified as a new minor allergen in tomato fruits. The recombinant tomato profilin comprises 131 amino acids and high sequence identity to other allergenic food and pollen profilins. It was shown to be IgE-reactive with a prevalence of 22% (11/50) in tomato-allergic patients. In patients with tomato allergy and multiple sensitization to other foods and birch pollen, IgE directed against tomato profilin showed a strong cross-reactivity with profilins from plant food sources and birch pollen. The tomato profilin was able to induce mediator release from human basophils. Conclusion:, The tomato profilin is a minor allergen in tomato fruit. Thus, it shows biological activity, as confirmed by in vitro histamine release assays with human basophils and thereby has the potential to account for clinical symptoms in tomato-allergic patients. [source] Glucocorticoids enhance interleukin-4 production to neo-antigen (hyaluronidase) in children immunocompromised with cytostatic drugsPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 5 2002Monika Edelbauer Immunoglobulin E (IgE)-mediated immediate-type allergic reactions to hyaluronidase have been observed in children with central nervous system (CNS) tumors. Glucocorticoids, used as therapy for brain edema, are discussed controversially as T helper 2 (Th2) stimulatory factors. In this study we investigated the role of glucocorticoids on a Th2 cytokine-promoting effect in children with CNS tumors. Peripheral blood mononuclear cells (PBMCs) from: 29 children suffering from malignant brain tumors, of whom 23 received short-term glucocorticoid treatment (for 3,4 days) during the course of chemotherapy; 18 children with nephrotic syndrome or renal transplantation receiving long-term glucocorticoid treatment; and 13 healthy children, were incubated with phytohemagglutinin (PHA) and/or anti-CD28 monoclonal antibody (mAb) and, in a second approach, with hyaluronidase. The concentrations of Th cell-mediated cytokines , interleukin (IL)-4, IL-10, and interferon-, (IFN-,) , were measured in supernatants. The IL-4 production of PBMCs incubated with PHA/anti-CD28 mAb from children with repeated co-administration of glucocorticoids, hyaluronidase, and cytostatic drugs (median: 249.9 pg/ml; range: 234.4,261.7) was significantly higher (p < 0.0001) than IL-4 production of PBMC from children of all the other groups (median: 86.18; range: 16.0,212.5). There was no significant difference in the levels of IL-10 and IFN-, within the groups. PBMCs stimulated only with hyaluronidase failed to produce detectable levels of cytokines. The results of this study indicate that repeated co-administration of glucocorticoids and hyaluronidase (a neo-antigen) enhance IL-4 production in vitro and thus may induce the production of specific IgE antibodies in children immunocompromised with cytostatic drugs. Hyaluronidase itself does not stimulate in vitro IL-4 synthesis in PBMCs of children receiving cytostatic drugs. [source] ,Eosinophilic Fungal Rhinosinusitis': A Common Disorder in Europe?THE LARYNGOSCOPE, Issue 2 2003Hannes Braun MD Abstract Objectives/Hypothesis The traditional criteria for the diagnosis of allergic fungal sinusitis include chronic rhinosinusitis, "allergic mucin" (mucus containing clusters of eosinophils), and detection of fungi by means of histological examination or culture. In 1999, a group of Mayo Clinic researchers, with a novel method of mucus collection and fungal culturing technique, were able to find fungi in 96% of patients with chronic rhinosinusitis. Immunoglobulin E,mediated hypersensitivity to fungal allergens was not evident in the majority of their patients. Because the presence of eosinophils in the allergic mucin, not a type I hypersensitivity, is probably the common denominator in the pathophysiology of allergic fungal sinusitis, the Mayo Clinic group proposed a change in terminology from allergic fungal sinusitis to eosinophilic fungal rhinosinusitis. Using new techniques of culturing fungi from nasal secretion, as well as preservation and histological examination of mucus, we investigated the incidence of "eosinophilic fungal rhinosinusitis" in our patient population. Study Design Methods In an open prospective study nasal mucus from patients with chronic rhinosinusitis as well as from healthy volunteers was cultured for fungi. In patients, who underwent functional endoscopic sinus surgery, nasal mucus was investigated histologically to detect fungi and eosinophils within the mucus. Results Fungal cultures were positive in 84 of 92 patients with chronic rhinosinusitis (91.3%). In all, 290 positive cultures grew 33 different genera, with 3.2 species per patient, on average. Fungal cultures from a control group of healthy volunteers yielded positive results in 21 of 23 (91.3%). Histologically, fungal elements were found in 28 of 37 patients (75.5%) and eosinophilic mucin in 35 of 37 patients (94.6%). Neither fungi nor eosinophils were present in 2 of 37 patients (5.4%). Conclusions Our data show that the postulated criteria of allergic fungal sinusitis are present in the majority of patients with chronic rhinosinusitis. Either those criteria will be found to be invalid and need to be changed or, indeed, "eosinophilic fungal rhinosinusitis" exists in the majority of patients with chronic rhinosinusitis. Based on our results, fungi and eosinophilic mucin appear to be a standard component of nasal mucus in patients with chronic rhinosinusitis. [source] Nasal Interleukin-5, Immunoglobulin E, Eosinophilic Cationic Protein, and Soluble Intercellular Adhesion Molecule-1 in Chronic Sinusitis, Allergic Rhinitis, and Nasal PolyposisTHE LARYNGOSCOPE, Issue 6 2000Matthias F. Kramer MD Abstract Objective To compare concentrations of interleukin-5 (IL-5), immunoglobulin E (IgE), eosinophilic cationic protein (ECP), and soluble intercellular adhesion molecule-1 (sICAM-1) in nasal secretion and serum of patients with chronic nonallergic sinusitis, allergic rhinitis, and nonallergic nasal polyposis to obtain information about the pathogenesis of these diseases. Methods Nasal secretion and serum were analyzed by routine enzyme-linked immunosorbent assay techniques. Nineteen patients with chronic nonallergic sinusitis, 24 patients with seasonal allergic rhinitis, and 18 patients with nonallergic nasal polyposis were included in the study. Eight healthy, nonallergic probands served as control subjects. Results Significantly elevated concentrations of IL-5 (5-fold, P < .05) and IgE (15-fold, P < .01) were detected in nasal secretion of patients with allergic rhinitis (IL-5, 51.8 ± 13.2 pg/mL; IgE, 41.9 ± 20.9 kU/L) or nonallergic nasal polyposis (IL-5, 57.9 ± 36.9 pg/mL; IgE, 40.5 ± 20.2 kU/L) compared with controls (IL-5, 10.6 ± 7.8 pg/mL; IgE, 2.8 ± 0.5 kU/L) or with patients with chronic nonallergic sinusitis (IL-5, 16.5 ± 13.2 pg/mL; IgE, 5.4 ± 3.1 kU/L). There were no significant differences between patients with allergic rhinitis and those with nonallergic nasal polyposis. Concentrations of ECP were significantly elevated (sixfold, P < .01) in patients with allergic rhinitis (297.8 ng/mL ± 173.1) compared with controls (52.4 ± 28.0 ng/mL) or patients with chronic nonallergic sinusitis (44.8 ± 40.1 ng/mL), whereas twofold higher concentrations (not significant) of ECP were observed in patients with nonallergic nasal polyposis (107.1 ± 26.6 ng/mL). Significantly elevated concentrations of sICAM-1 in nasal secretion (threefold, P < .05) were detected only in patients with chronic nonallergic sinusitis (79.4 ± 45.6 ng/mL). The elevated sICAM-1 nasal secretion values in this group correlated significantly (P < .05) to the serum values. Conclusions Equally elevated concentrations of IL-5 and IgE in patients with allergic rhinitis and nonallergic nasal polyposis implicated similar pathogenic processes in both diseases. Whereas the pathogenesis of allergic rhinitis is IgE-specific, the pathogenesis of nasal polyps is not as clear. IL-5 was suggested to play a pivotal role in tissue eosinophilia, which was confirmed by data in the present study. Elevated concentrations of ECP were suggested to result from tissue eosinophilia,a characteristic of both diseases. Elevated concentrations of sICAM-1 in patients with chronic nonallergic sinusitis pointed to its key role in the recruitment of neutrophils into the inflamed tissue, whereas an important role in eosinophil recruitment was ruled out. [source] The 21st century renaissance of the basophil?EXPERIMENTAL DERMATOLOGY, Issue 11 2006Current insights into its role in allergic responses, innate immunity Abstract:, Basophils and mast cells express all the three subchains of the high-affinity immunoglobulin E (IgE) receptor Fc,RI and contain preformed histamine in the cytoplasmic granules. However, it is increasingly clear that these cells play distinct roles in allergic inflammatory disease. Despite their presence throughout much of the animal kingdom, the physiological function of basophils remains obscure. As rodent mast cells are more numerous than basophils, and generate an assortment of inflammatory cytokines, basophils have often been regarded as minor players in allergic inflammation. In humans, however, basophils are the prime early producers of interleukin (IL)-4 and IL-13, T helper (Th)2-type cytokines crucial for initiating and maintaining allergic responses. Basophils also express CD40 ligand which, in combination with IL-4 and IL-13, facilitates IgE class switching in B cells. They are the main cellular source for early IL-4 production, which is vital for the development of Th2 responses. The localization of basophils in various tissues affected by allergic inflammation has now been clearly demonstrated by using specific staining techniques and the new research is shedding light on their selective recruitment to the tissues. Finally, recent studies have shown that basophil activation is not restricted to antigen-specific IgE crosslinking, but can be caused in non-sensitized individuals by a growing list of parasitic antigens, lectins and viral superantigens, binding to non-specific IgE antibodies. This, together with novel IgE-independent routes of activation, imparts important new insights into the potential role of basophils in both adaptive and innate immunity. [source] The role of reactive oxygen species and nitric oxide in mast cell-dependent inflammatory processesIMMUNOLOGICAL REVIEWS, Issue 1 2007Emily J. Swindle Summary:, Reactive oxygen species (ROS) and reactive nitrogen oxide species (RNOS), including nitric oxide, are produced in cells by a variety of enzymatic and non-enzymatic mechanisms. At high levels, both types of oxidants are used to kill ingested organisms within phagocytes. At low levels, RNOS may diffuse outside cells where they impact the vasculature and nervous system. Recent evidence suggests that low levels of ROS produced within cells are involved in cell signaling. Along with these physiological roles, many pathological conditions exist where detrimental high-level ROS and RNOS are produced. Many situations in which ROS/RNOS are associated also involve mast cell activation. In innate immunity, such mast cells are involved in the immune response toward pathogens. In acquired immunity, activation of mast cells by cross-linking of receptor-bound immunoglobulin E causes the release of mediators involved in the allergic inflammatory response. In this review, we describe the principle pathways for ROS and RNOS generation by cells and discuss the existence of such pathways in mast cells. In addition, we examine the evidence for a functional role for ROS and RNOS in mast cell secretory responses and discuss evidence for a direct relationship between ROS, RNOS, and mast cells in mast cell-dependent inflammatory conditions. [source] Control of IL-4 expression in T helper 1 and 2 cellsIMMUNOLOGY, Issue 4 2008Jane Gilmour Summary The mechanism of differentiation of naïve T cells to a variety of effector lineages, but particularly to T helper type 1 (Th1) and Th2 cells, has been the subject of intense scrutiny over the past two decades. Studies have revealed that the expression of cytokines, receptors, signalling molecules, transcription factors, DNA methylating enzymes and histone-modifying enzymes is altered during the process and has been shown to play a co-ordinated role to facilitate expression of the cytokines interleukin-4 (IL-4), IL-5 and IL-13 in Th2 cells, or interferon-, in Th1 cells. Regulation of IL-4 expression has been of particular interest for two main reasons: first because IL-4 acts as a growth factor for Th2 cells, and second because of its role in the induction of immunoglobulin class switching to immunoglobulin E, which plays a critical role in mediating allergic responses. Study of the pathways that promote this tissue-restricted expression of IL-4 may highlight potential areas for therapeutic intervention. [source] Human dendritic cells transfected with allergen-DNA stimulate specific immunoglobulin G4 but not specific immunoglobulin E production of autologous B cells from atopic individuals in vitroIMMUNOLOGY, Issue 2 2007Bettina König Summary Atopic/allergic diseases are characterized by T helper 2 (Th2)-dominated immune responses resulting in immunoglobulin E (IgE) production. DNA-based immunotherapies have been shown to shift the immune response towards Th1 in animal models. In further studies we showed that human dendritic cells (DC) transfected with allergen-DNA are able to stimulate autologous CD4+ T cells from atopic individuals to produce Th1 instead of Th2 cytokines and to activate interferon-, (IFN-,)-producing CD8+ T cells. The aim of this study was to analyse whether DC transfected with allergen-DNA are also able to influence immunoglobulin production of B cells from atopic donors. For this purpose, human monocyte-derived DC from grass-pollen allergic donors were transfected with an adenovirus encoding the allergen Phleum pratense 1 and cocultured with B cells, autologous CD4+ T cells, and CD40 ligand-transfected L-cells. B cells receiving help from CD4+ T cells stimulated with allergen-transfected dendritic cells produced more allergen-specific IgG4 compared to stimulation with allergen protein pulsed DC or medium, while total IgG4 production was not affected. In contrast, specific IgE production was not enhanced by stimulation with allergen-DNA transfected DC compared to medium and inhibited compared to allergen protein-pulsed DC with similar effects on total IgE production in vitro. Allergen-DNA transfected dendritic cells are able to direct the human allergic immune response from Th2-dominance towards Th1 and Tc1 also resulting in decreased IgE and increased IgG4 production. [source] Pregnancy, but not the allergic status, influences spontaneous and induced interleukin-1, (IL-1,), IL-6, IL-10 and IL-12 responsesIMMUNOLOGY, Issue 1 2006Petra Amoudruz Summary In this study, we investigated how pregnancy influences cytokine production in response to stimulation of the innate and the adaptive immune system, respectively. Peripheral blood mononuclear cells (PBMCs) from allergic (n = 44) and non-allergic (n = 36) women were collected at three time-points: during the third trimester, at delivery and at a non-pregnant state 2 years after delivery. The production of interleukin-1, (IL-1,), IL-6, IL-10 and IL-12 was measured by enzyme-linked immunosorbent assay (ELISA) or enzyme-linked immunospot assay (ELISPOT). The spontaneous cytokine production, and the response following stimulation with agents that primarily activate the adaptive part of the immune system [phytohaemagglutinin (PHA), allergen extracts from cat and birch], or lipopolysaccharide (LPS) that activate innate immunity was measured in vitro. There was a significantly higher spontaneous in vitro production of IL-1,, IL-6 and IL-10 by PBMCs during pregnancy than 2 years after pregnancy, and this was not affected by the allergic status of the women. Conversely, in PHA-stimulated cell cultures there was a lower production of IL-10 and IL-12 during pregnancy than 2 years after pregnancy. LPS-induced IL-6 levels were significantly lower in PBMCs obtained during pregnancy than at 2 years after pregnancy. In addition, we made the interesting observation that in allergic women total immunoglobulin E (IgE) levels were significantly lower 2 years after pregnancy compared to the levels during pregnancy. Taken together, our results indicate that while atopic allergy in women does not have a substantial effect on cytokine production, pregnancy has an obvious effect on the immune system in terms of cytokine production as well as on the total IgE levels. [source] A T2 cytokine environment may not limit T1 responses in human immunodeficiency virus patients with a favourable response to antiretroviral therapyIMMUNOLOGY, Issue 1 2006Patricia Price Summary Low-level production of interferon-, (IFN-,) marks human immunodeficiency virus (HIV)-induced immunodeficiency and has been ascribed to a bias towards T2 cytokines. This was investigated in two cross-sectional studies of HIV patients who were immunodeficient when they began antiretroviral therapy (ART) and had stable increases in CD4 T-cell counts. Blood leucocytes were assessed unstimulated or after stimulation with cytomegalovirus (CMV), anti-CD3 or mitogen. IFN-, and interleukin (IL)-5 responses were initially assessed by enzyme-linked immunosorbent spot-forming cell assay (ELISPOT) and enzyme-linked immunosorbent assay (ELISA). We then adopted a sensitive reverse transcription,polymerase chain reaction (RT,PCR) system to assess IFN-,, IL-5, IL-4 and IL-4,2 (an inhibitory splice variant of IL-4) mRNA. The results were correlated with putative serological markers of a T1 [lymphocyte activation gene-3 (LAG-3), CD26] or a T2 [CD30, immunoglobulin E (IgE)] cytokine environment. IL-5 production and IgE levels were elevated in patients. IgE levels did not correlate with IFN-,, but showed an inverse correlation with IL-5 released in culture (P = 0·05). The levels of IL-4, IFN-,, IL-5 and IL-4,2 mRNA were correlated after anti-CD3 stimulation, where IL-5 was the best predictor of IFN-, mRNA (P = 0·006). Weak positive correlations were evident between CD30 and cytokine mRNA levels, whilst IgE correlated inversely with IL-4, IL-4,2, IL-5 and IFN-, mRNA levels. These analyses provide no evidence for an inverse relationship between T1 and T2 cytokine responses in HIV patients, but suggest that the elevation of IgE marks low cytokine responses. [source] Mechanisms of immune suppression by interleukin-10 and transforming growth factor-,: the role of T regulatory cellsIMMUNOLOGY, Issue 4 2006Alison Taylor Summary Specific immune suppression and induction of tolerance are essential processes in the regulation and circumvention of immune defence. The balance between allergen-specific type 1 regulatory (Tr1) cells and T helper (Th) 2 cells appears to be decisive in the development of allergy. Tr1 cells consistently represent the dominant subset specific for common environmental allergens in healthy individuals. In contrast, there is a high frequency of allergen-specific interleukin-4 (IL-4)-secreting T cells in allergic individuals. Allergen-specific immunotherapy can induce specific Tr1 cells that abolish allergen-induced proliferation of Th1 and Th2 cells, as well as their cytokine production. Tr1 cells utilize multiple suppressor mechanisms, such as IL-10 and transforming growth factor-, (TGF-,) as secreted cytokines and various surface molecules, such as cytotoxic T-lymphocyte antigen 4 and programmed death-1. IL-10 only inhibits T cells stimulated by low numbers of triggered T-cell receptors, which depend on CD28 costimulation. IL-10 inhibits CD28 tyrosine phosphorylation, preventing the binding of phosphatidylinositol 3-kinase p85 and consequently inhibiting the CD28 signalling pathway. In addition, IL-10 and TGF-, secreted by Tr1 cells skew the antibody production from immunoglobulin E (IgE) towards the non-inflammatory isotypes IgG4 and IgA, respectively. Induction of antigen-specific Tr1 cells can thus re-direct an inappropriate immune response against allergens or auto-antigens using a broad range of suppressor mechanisms. [source] A novel model of sensitization and oral tolerance to peanut proteinIMMUNOLOGY, Issue 3 2004Jessica Strid Summary The prevalence of food allergic diseases is rising and poses an increasing clinical problem. Peanut allergy affects around 1% of the population and is a common food allergy associated with severe clinical manifestations. The exact route of primary sensitization is unknown although the gastrointestinal immune system is likely to play an important role. Exposure of the gastrointestinal tract to soluble antigens normally leads to a state of antigen-specific systemic hyporesponsiveness (oral tolerance). A deviation from this process is thought to be responsible for food-allergic diseases. In this study, we have developed a murine model to investigate immunoregulatory processes after ingestion of peanut protein and compared this to a model of oral tolerance to chicken egg ovalbumin (OVA). We demonstrate that oral tolerance induction is highly dose dependent and differs for the allergenic proteins peanut and OVA. Tolerance to peanut requires a significantly higher oral dose than tolerance to OVA. Low doses of peanut are more likely to induce oral sensitization and increased production of interleukin-4 and specific immunoglobulin E upon challenge. When tolerance is induced both T helper 1 and 2 responses are suppressed. These results show that oral tolerance to peanut can be induced experimentally but that peanut proteins have a potent sensitizing effect. This model can now be used to define regulatory mechanisms following oral exposure to allergenic proteins on local, mucosal and systemic immunity and to investigate the immunomodulating effects of non-oral routes of allergen exposure on the development of allergic sensitization to peanut and other food allergens. [source] Enhanced interleukin-4 production in CD4+ T cells and elevated immunoglobulin E levels in antigen-primed mice by bisphenol A and nonylphenol, endocrine disruptors: involvement of nuclear factor-AT and Ca2+IMMUNOLOGY, Issue 1 2003Mee H. Lee Summary Bisphenol A (BPA) and p -nonylphenol (NP) are representative endocrine disruptors (EDs) that may have adverse effects on human health. The influence of these compounds on allergic immune responses remains unclear. In this study, we have examined the effects of BPA and NP on production of interleukin-4 (IL-4), a pro-inflammatory cytokine closely associated with allergic immune responses. Both BPA and NP significantly enhanced IL-4 production in keyhole limpet haemocyanin (KLH)-primed CD4+ T cells in a concentration-dependent manner. Treatment with BPA or NP in vivo resulted in significant increase of IL-4 production in CD4+ T cells and of antigen-specific immunoglobulin E (IgE) levels in the sera of KLH-primed mice. Furthermore, BPA and NP enhanced the activation of IL-4 gene promoter in EL4 T cells transiently transfected with IL-4 promoter/reporter constructs, and the enhancing effect mapped to a region in the IL-4 promoter containing binding sites for nuclear factor (NF)-AT. Activation of T lymphocytes by phorbol 12-myristate 13-acetate/ionomycin resulted in markedly enhanced binding activities to the NF-AT site, which significantly increased upon addition of BPA or NP, as demonstrated by the electrophoretic mobility shift assay, indicating that the transcription factor NF-AT was involved in the enhancing effect of BPA and NP on IL-4 production. The enhancement of IL-4 production by BPA or NP was significantly reduced by nitrendipine, a blocker of Ca2+ influx, and by FK506, a calcineurin inhibitor. FK506 inhibited the NF-AT,DNA binding activity and IL-4 gene promoter activity enhanced by BPA or NP. These results represent the first report describing possible enhancement of allergic response by EDs through increasing IL-4 production in CD4+ T cells and antigen-specific IgE levels in the sera via the stimulation of Ca2+/calcineurin-dependent NF-AT activation. [source] Studies on the association between immunoglobulin E autoreactivity and immunoglobulin E-dependent histamine-releasing factorsIMMUNOLOGY, Issue 2 2002Ilona Kleine Budde Summary It has been reported that serum immunoglobulin E (IgE) from certain atopic patients can sensitize basophils to release histamine in response to IgE-dependent histamine-releasing factors (HRFs). It has also been shown that patients suffering from severe forms of atopy may contain IgE autoantibodies. It was investigated whether HRF-responsive sera contained IgE autoantibodies and if there was an association between IgE autoreactivity and IgE-dependent responsiveness to HRF. The presence of HRF-responsive IgE (IgE+) in serum of patients with respiratory atopy was determined by stimulating stripped human basophils sensitized by serum with peripheral blood mononuclear cell (PBMC)-derived HRF, and measuring the release of histamine. In parallel, these sera were screened for the presence of IgE autoantibodies to nitrocellulose-blotted human cellular extracts. The capacity of IgE autoantigen-containing preparations to induce histamine release was tested in the stripped basophil assay. Eleven out of 52 sera contained IgE autoantibodies to blotted cellular extracts of human PBMCs or of the human epithelial cell line A431. No significant association was found between IgE autoreactivity and IgE-dependent responsiveness to HRF: 7/26 IgE+ sera contained IgE to human cellular extracts, and 4/26 of the sera without IgE+ did also. IgE autoantigen-containing extracts did not induce histamine release of appropriately sensitized basophils. By size-exclusion chromatography it was shown that a 32,000 MW autoantigen eluted in the >55,000 MW fraction, which indicates that this protein forms polymers or complexes with other macromolecules. This might explain the discrepancy between binding and histamine-releasing activity. A 20,000 MW IgE-defined autoantigen cross-reacted with a shrimp allergen. Our results indicate that IgE-reactivity to immunoblotted human protein and IgE-dependent HRF activity are distinct entities that may co-occur in atopic patients. [source] Rat mast cell protease-I enhances immunoglobulin E production by mouse B cells stimulated with interleukin-4IMMUNOLOGY, Issue 3 2001Tsutomu Yoshikawa Summary Mast cell chymase plays important roles in inflammation and tissue remodeling. Here we show that mast cell chymase also functions as an enhancer of immunoglobulin production. In the culture of murine spleen cells stimulated with lipopolysaccharide and interleukin-4, purified rat chymase (rat mast cell protease-I; RMCP-I), at physiological concentrations, enhanced immunoglobulin E (IgE) and IgG1 syntheses but not IgG3 synthesis. The enhancement was also evident when spleen cells depleted of T cells and macrophages were employed as responding cells. Enzymatic activity of RMCP-I was required to enhance IgE and IgG1, because two inhibitors for chymotryptic enzymes, chymostatin and Y-40613, a novel chymase inhibitor, suppressed the enhanced immunoglobulin production, and phenylmethylsulphonyl fluoride, an irreversible inhibitor for serine proteases, totally abolished the enhancing effect. Furthermore, a specific inhibitor for Zn2+ -dependent metalloproteases, GI 129471, could also completely inhibit the production of IgE and IgG1 that was enhanced by RMCP-I, suggesting that a metalloprotease also played an essential role in the immunoglobulin production. Our results together with others show that proteases from mast cell granules have important function not only in the efferent phase but also in the afferent phase of immune responses. [source] Naturally occurring polyphenolic antioxidants modulate IgE-mediated mast cell activationIMMUNOLOGY, Issue 4 2000S.-S. Chen Summary Reactive oxygen species (ROS) are known to modulate activities of a host of kinases, phosphatases and transcription factors. Rutin and chlorogenic acid (CGA) are the major polyphenolic antioxidants present in the small molecular fraction of smokeless tobacco leaf extracts, as ascertained by reverse-phase high-pressure liquid chromatography (HPLC) and mass spectrometry. Levels of intracellular ROS in resting versus antigen,immunoglobulin E (IgE)-challenged murine mast cells were measured at 510 nm by fluorescence-activated cell sorting (FACS) using carboxy-dichlorofluorescein (DCFH-DA). Enhanced ROS production was observed in IgE-sensitized mast cells following antigenic challenge. Rutin and CGA reduced ROS levels in antigen,IgE-activated mast cells. Concomitantly, they also profoundly inhibited histamine release by these activated mast cells. In contrast, rutin and CGA augmented the inducible cytokine messages, i.e. interleukin (IL)-10, IL-13, interferon-, (IFN-,), IL-6 and tumour necrosis factor-, (TNF-,) in IgE-sensitized mast cells following antigen challenge. This study indicates that tobacco polyphenolic antioxidants that quench intracellular ROS, differentially affect two effector functions of antigen,IgE-activated mast cells. This model system may be employed to determine the molecular target of polyphenols. The potential role of these polyphenolic antioxidants on IgE-mediated allergy in vivo depends on a balance of their differential effects on mast cell activation. [source] An Outbreak of Respiratory Diseases among Workers at a Water-Damaged Building , A Case ReportINDOOR AIR, Issue 3 2000MARKKU SEURI Abstract We describe a military hospital building with severe, repeated and enduring water and mold damage, and the symptoms and diseases found among 14 persons who were employed at the building. The exposure of the employees was evaluated by measuring the serum immunoglobulin G (IgG)-antibodies against eight spieces of mold and yeast common in Finnish water and mold damaged buildings and by sampling airborne viable microbes within the hospital. The most abundant spieces was Sporobolomyces salmonicolor. All but one of the employees reported some building-related symptoms, the most common being a cough which was reported by nine subjects. Four new cases of asthma, confirmed by S. salmonicolor inhalation provocation tests, one of whom was also found to have alveolitis, were found among the hospital personnel. In addition, seven other workers with newly diagnosed rhinitis reacted positively in nasal S. salmonicolor provocation tests. Skin prick tests by Sporobolomyces were negative among all 14 workers. Exposure of the workers to mold and yeast in the indoor air caused an outbreak of occupational diseases, including asthma, rhinitis and alveolitis. The diseases were not immunoglobulin E (IgE)-mediated but might have been borne by some other, as yet unexplained, mechanism. [source] IgE, allergy, and risk of glioma: Update from the San Francisco Bay Area Adult Glioma Study in the Temozolomide eraINTERNATIONAL JOURNAL OF CANCER, Issue 3 2009Joseph L. Wiemels Abstract The consistently observed inverse relationship of allergic conditions with glioma risk and our previous demonstration that immunoglobulin E (IgE) levels also were lower in glioma patients than controls suggest that atopic allergy may be related to a mechanism that inhibits or prevents glioma. We sought to extend these results with a new and larger series of patients (n = 535 with questionnaire data; 393 with IgE measures) and controls (n = 532 with questionnaire data; 470 with IgE measures). As expected, glioma cases were less likely than controls to report history of allergies [among self-reported cases, Odds ratios (OR) = 0.59, 95% confidence interval (CI): 0.41,0.85]. IgE levels also were lower in glioma cases versus controls (OR per unit log IgE = 0.89, 95% CI (0.82,0.98). However, this inverse relationship was only apparent among cases receiving temozolomide, a treatment which became part of the "standard of care" for glioblastoma patients during the study period. Among patients receiving temozolomide, IgE levels in cases whose blood samples were obtained within 30 days of diagnosis were slightly higher than controls, whereas IgE levels in cases whose blood sample was obtained >60 days after diagnosis were significantly lower than controls (OR = 0.80; 95% CI: 0.71,0.89). Thus, although our results robustly confirm the inverse association between allergy and glioma, the results for IgE are affected by temozolomide treatments which may have influenced IgE levels. These results have implications for the study of immunologic factors in glioma as well as for immunotherapy protocols for treating glioma. © 2009 UICC [source] Extensive xanthelasma associated with anaplastic large cell lymphoma and hyperimmunoglobulin E syndromeINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2003Mi-Woo Lee MD A 57-year-old woman presented with a 6-month history of an extensively spreading, yellowish patch on the periorbital areas and cheeks. A diagnosis of hyperimmunoglobulin E syndrome had been made at the age of 22 years on the basis of an eczematous eruption, recurrent furunculosis, and a persistently elevated immunoglobulin E (IgE) level. Her past medical history revealed that she had suffered from numerous recurrent bouts of chronic sinusitis, otitis media, oral candidiasis, orbital cellulitis, acne rosacea, and pneumonia caused by cytomegalovirus since her twenties. In addition, 1 year ago, anaplastic large cell lymphoma of the cervical lymph node (stage IIIb) developed, and she received six cycles of cyclophosphamide,doxorubicin,vincristine,prednisolone (CHOP) chemotherapy with partial remission. None of her family had any of these problems. Cutaneous examination showed extensive, symmetric, noninfiltrated macular areas of distinct yellow discoloration around the eyes and on both cheeks (Fig. 1). There were also erythematous papulonodular eruptions on the nose and both cheeks, which were thought to be acne rosacea. Laboratory findings were normal, except for an elevated IgE level (8157 IU/mL). Serum concentrations of IgG, IgA, and IgM were normal. Serum complement levels were normal, as evidenced by normal C3, C4, and CH50. Although she had a previous history of a decreased level (12%) of nitroblue tetrazolium (NBT) test (control, 53%), NBT test at our institute was normal. Neutrophil function tests, including neutrophil chemotaxis, neutrophil phagocytosis, neutrophil respiratory burst, and neutrophil microbial killing test, by flow cytometry, showed normal results. The serum lipid levels, including total cholesterol, triglyceride, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol, were normal. Serum lipoprotein electrophoresis was normal. A biopsy specimen revealed scattered foamy cells throughout the dermis. The larger clusters of foamy cells tended to group around the blood vessels of the dermis (Fig. 2). Figure 1. Extensively distributed, yellowish, flat xanthelasma on the face Figure 2. Clusters of foamy cells around the blood vessels of the dermis (hematoxylin and eosin, ×400) [source] Antiallergic Activities of Pigmented Rice Bran Extracts in Cell AssaysJOURNAL OF FOOD SCIENCE, Issue 9 2007Sun Phil Choi ABSTRACT:, Using a panel of chemical, biochemical, and cell assays, we determined inhibitory effects of extracts of the pigmented black rice brans on in vitro allergic reactions. Ethanol-water (70% v/v) extracts from 5 pigmented brans were found to be more effective than an extract from a nonpigmented rice cultivar in suppressing the release of histamine and ,-hexosaminidase from basophilic RBL-2H3 cells stimulated with both Ionophore A23187 and immunoglobulin E (IgE)-antigen complexes. Suppression was also obtained with A23187-stimulated rat peritoneal mast cells. The extent of inhibition of these 2 markers of the immune response was accompanied by an influx of calcium ions. The inhibition of the immune process by the pigmented brans was confirmed by the observed modulation of the proinflammatory cytokine gene expressions and cytokine release, as indicated by the reduction in tumor necrosis factor (TNF)-,, interleukin (IL)-1,, IL-4, and IL-6 mRNA expressions determined with the reverse transcription-polymerase chain reaction (RT-PCR). Reduction of TNF-,, IL-1,, and IL-6 protein release from both the cultured cell line and peritoneal cells was further confirmed by enzyme-linked immunoadsorbent assays. Rice bran from the LK1-3-6-12-1-1 cultivar was the most effective inhibitor in all assays. This particular rice variety merits further evaluation as part of a human diet to ascertain its potential to protect against allergic diseases such as hay fever and asthma. [source] Hypotensive shock and angio-oedema from angiotensin II receptor blocker: a class effect in spite of tripled tryptase valuesJOURNAL OF INTERNAL MEDICINE, Issue 4 2005E. W. NIELSEN Abstract. In adverse reactions with shock, tripled tryptase values can support a diagnosis of anaphylaxis. A 51-year old physically fit woman experienced angio-oedema and hypotensive shock after irbesartan ingestion requiring noradrenaline infusion. Serum tryptase rose to three times the normal value. Total immunoglobulin E and skin prick tests were normal, however. As nonallergic increases in tryptase have been observed, e.g. during angio-oedema from angiotensin-converting enzyme inhibitors, and bradykinin itself can degranulate mast cells acutely, we interpret the reaction as a class effect. To our knowledge, our report is one of the first on shock and angio-oedema from irbesartan. [source] Association of IL-4 589 C/T promoter and IL-4R,I50V receptor polymorphism with susceptibility to HIV-1 infection in North IndiansJOURNAL OF MEDICAL VIROLOGY, Issue 6 2009Animesh Chatterjee Abstract The clinical course and outcome of HIV-1 infection are highly variable among individuals. Interleukin 4 (IL-4) is a key T helper 2 cytokine with various immune-modulating functions including induction of immunoglobulin E (IgE) production in B cells, downregulation of CCR5 and upregulation of CXCR4, the main co-receptors for HIV. Our objective is to investigate whether single-nucleotide polymorphisms (SNPs) in the IL-4 promoter 589 C/T and IL-4 R, I50V affect the susceptibility to HIV infection and its progression to AIDS in North Indian individuals. The study population consisted of 180 HIV-1 seropositive (HSP) stratified on the basis of disease severity (stage I, II, III), 50 HIV-1 exposed seronegative (HES), and 305 HIV-1 seronegative (HSN) individuals. The subjects were genotyped for IL-4 589 C/T promoter polymorphism and IL-4 R, I50V by polymerase chain reaction restriction fragment length polymorphism. The results showed that IL-4 589 C/T was not associated with the risk of HIV infection and disease progression. However, the IL-4R, I50 allele and genotype was significantly increased in HSP compared to HSN and HSP and was associated with risk of HIV infection. The frequency of IL-4R, I50 allele in the HSP group was higher than in HSN (76.11 vs. 64.75%; P,=,0.000; OR,=,1.734) and HES (76.11% vs. 62.00%; P,=,0.007; OR,=,1.953). Homozygous IL-4R, I50I genotype was significantly increased in HSP group compared with HSN (58.88% vs. 44.26%; P,=,0.002; OR,=,1.804) and HES (58.88% vs. 42.00%; P,=,0.038; OR,=,1.978). The present study for the first time suggests an association of IL-4R, I50 allele with increased likelihood of HIV-1 infection in North Indian population. Further studies are required to confirm these findings and understand the effect of IL-4R, polymorphism on the outcome of HIV-1 infection. J. Med. Virol. 81:959,965, 2009. © 2009 Wiley-Liss, Inc. [source] Links Between Anxiety and Allergies: Psychobiological Reality or Possible Methodological Bias?JOURNAL OF PERSONALITY, Issue 2 2009Alice M. Gregory ABSTRACT The objective of the study was to examine the link between anxiety and allergies to establish whether it reflects a psychobiological reality or a possible methodological bias. A cohort of 1,037 children enrolled in the study. Anxiety disorders were assessed between 11 and 21 years. Anxious personality was assessed at 18 years. Allergies were examined at 21 years by (a) self reports, (b) skin pricks, and (c) serum total immunoglobulin E (IgE). Self-reported allergies were predicted by recurrent anxiety disorders (OR [95% CI]=1.56 [1.06,2.30], p=.023) and self-reports of anxious personality (OR [95% CI]=1.67 [1.17,2.37], p=.004): Objectively verified allergies were not. These results suggest that the link between anxiety and allergies may reflect a methodological artifact rather than a psychobiological reality. [source] Piperine inhibits eosinophil infiltration and airway hyperresponsiveness by suppressing T cell activity and Th2 cytokine production in the ovalbumin-induced asthma modelJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 3 2009Seung-Hyung Kim Abstract Objectives This study aimed to investigate the effect of piperine on airway hyper-responsiveness, pulmonary eosinophilic infiltration, various immune cell phenotypes, Th2 cytokine production, immunoglobulin E and histamine production in a murine model of asthma. Methods Asthma was induced in Balb/c mice by ovalbumin sensitization and inhalation. Piperine (4.5 and 2.25 mg/kg) was orally administered 5 times a week for 8 weeks. At 1 day after the last ovalbumin exposure, airway hyperresponsiveness was determined and samples of bronchoalveolar lavage fluid, lung cells and serum were collected for further analysis. Key findings Piperine-treated groups had suppressed eosinophil infiltration, allergic airway inflammation and airway hyperresponsiveness, and these occurred by suppression of the production of interleukin-4, interleukin-5, immunoglobulin E and histamine. Moreover, polymerase chain reaction products for thymus and activation regulated chemokine from lung cell RNA preparations were decreased in the piperine-treated group compared with control groups, although transforming growth factor-, products were increased in the piperine-treated group. Conclusions The results suggest that the therapeutic mechanism by which piperine effectively treats asthma is based on a reduction of Th2 cytokines (interleukin-4, interleukin-5), eosinophil infiltration, and by marked reduction of thymus and activation regulated chemokine, eotaxin-2 and interleukin-13 mRNA expression (especially transcription of nuclear factor-, dependent genes) in lung tissue, as well as reduced interleukin-4, interleukin-5 and eotaxin levels in bronchoalveolar lavage fluid, and histamine and ovalbumin-specific immunoglobulin E production in serum. [source] Interstitial Cystitis and the Therapeutic Effect of Suplatast TosilateLUTS, Issue 2009Yukio HAYASHI Painful bladder syndrome (PBS)/interstitial cystitis (IC) can be a chronic and debilitating disease characterized by urinary urgency, frequency, and bladder pain, which are often very difficult to treat, regardless of currently-proposed treatments. Suplatast tosilate (IPD-1151T) is an immunoregulator that suppresses Th2 cytokine production, immunoglobulin E (IgE) synthesis, chemical mediator release from mast cells, and eosinophilic recruitment. In a preliminary, open-label clinical study of IPD-1151T in 14 women with IC, treatment with IPD-1151T significantly increased bladder capacity and decreased urinary urgency, urinary frequency, and lower abdominal pain, as measured by the IC symptom index, in patients with non-ulcerative IC. A concomitant reduction in immunological parameters (eosinophils, IgE, and urine T cells) was observed. Also, in basic experimental studies using hydrochloric acid-induced chronic cystitis rats, the oral administration of IPD-1151T (0.1,100 mg/kg/day) for 7 days after the induction of cystitis dose dependently increased the intercontraction intervals and micturition volume. In addition, the infiltration of mast cells and eosinophils into the bladder was suppressed by IPD-1151T. These findings suggest that IPD-1151T could be a new medicine for treating debilitating symptoms, such as bladder pain and urinary frequency in PBS/IC. [source] Birth-related factors and doctor-diagnosed wheezing and allergic sensitization in early childhoodALLERGY, Issue 9 2010L. Keski-Nisula To cite this article: Keski-Nisula L, Karvonen A, Pfefferle PI, Renz H, Büchele G, Pekkanen J. Birth-related factors and doctor-diagnosed wheezing and allergic sensitization in early childhood. Allergy 2010; 65: 1116,1125. Abstract Background:, To investigate the associations between clinical obstetric factors during birth and doctor-diagnosed wheezing and allergic sensitization during early childhood. Methods:, We followed 410 Finnish women from late pregnancy until 18 months age of their children. All children were delivered at term. Doctor-diagnosed wheezing among children was established by questionnaires, while specific immunoglobulin E antibodies to inhalant and food allergens were measured in 388 children at 1 year of age. Data on maternal obstetric variables were recorded at the time of delivery. Results:, Children of mothers with longer duration of ruptured fetal membranes before birth had significantly higher risk of doctor-diagnosed wheezing during early childhood compared to those children with shorter period of ruptured fetal membranes (III vs I quartile; aOR 6.65, 95% CI 1.99,22.18; P < 0.002 and IV vs I quartile; aOR 3.88, 95% CI 1.05,14.36, P < 0.043). Children who were born by Cesarean delivery had significantly less allergic sensitization at the age of 1 year compared to those who were born by vaginal route (16.0%vs 32.2%; aOR 0.34, 95% CI 0.14,0.80; P < 0.013). Furthermore, allergic sensitization tended to be more common in children with longer duration of labor before birth. No other birth-related obstetric factors, such as induction, the type of fetal membrane rupture during birth or quality of amniotic fluid were associated significantly with the examined outcomes. Conclusion:, The longer duration of the ruptured fetal membranes possibly reflected the higher risk of intrapartum infection at birth, and further increased the risk of doctor-diagnosed wheezing among offspring. [source] |