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Asthma exacerbations are triggered by rhinovirus infections. We employed a systems biology approach to delineate upper-airway gene network patterns underlying asthma exacerbation phenotypes in children. Cluster analysis unveiled distinct IRF7hi versus IRF7lo molecular phenotypes, the former exhibiting robust upregulation of Th1/type I IFN responses and the latter an alternative signature marked by upregulation of cytokine and growth factor signaling and downregulation of IFN-?. The two phenotypes also produced distinct clinical phenotypes. For IRF7lo children, symptom duration prior to hospital presentation was more than twice as long from initial symptoms (p = 0.011) and nearly three times as long for cough (p < 0.001), the odds ratio of admission to hospital was increased more than 4-fold (p = 0.018), and time to recurrence was shorter (p = 0.015). In summary, our findings demonstrate that asthma exacerbations in children can be divided into IRF7hi versus IRF7lo phenotypes with associated differences in clinical phenotypes.

© 2018 Owens et al. Purpose: The aim of this study was to longitudinally assess the prevalence of allergic sensitization, asthma, eczema and hay fever from infancy to adulthood in a single cohort. Participants and methods: This prospective study is based on a longitudinal birth cohort of 253 participants, with respiratory and immunological assessments at 1, 6, 11, 18 and 24 years of age. Subjects were recruited from an urban maternity hospital. Retention rates varied from 45% to 72% at follow-up assessments. Asthma diagnosis was based on physician diagnosis of asthma and symptoms/medications in the previous 12 months. Allergic sensitization was defined by the positive skin prick test. Hay fever and eczema were based on a questionnaire. Results: The prevalence of allergic sensitization rose from 19% (n=33) at 1 year of age to 71% (n=77) at 24 years of age. The rate of asthma halved from 25% at 6 years of age to 12%–15% between 11 and 24 years of age, but the prevalence of allergic sensitization among those with asthma doubled from 50% at 6 years of age to 100% at 24 years of age. Hay fever rates rose throughout childhood from 7% at 6 years of age to 44% at 24 years of age, while the prevalence of eczema reduced from 25% at 6 years of age to 16% at 24 years of age. Parental atopy doubled the odds of asthma in their offspring by 24 years of age (odds ratio [OR]= 2.63, 95% CI 1.1–6.2, p=0.029). In all, 74% of those with asthma at 24 years of age also reported hay fever. The relationship between eczema and asthma was only significant up to 11 years of age, and the relationship between hay fever and asthma was stronger in adolescence and early adulthood than in early childhood. Conclusion: Patterns of atopic disorders vary throughout childhood. Although the prevalence of allergic sensitization and hay fever rose throughout childhood and the prevalence of asthma reduced, the strength of their relationship with asthma increased with age.

Respiratory virus infections account for a significant proportion of acute admissions to the paediatric intensive care unit (PICU). Recent studies have shown that rhinoviruses (RV) are the most frequent virus detected in severe cases of acute respiratory illnesses (ARI) admitted to a PICU. The aim of this study was to determine the prevalence of different viruses, in particular RV species, in children with ARI admitted to a tertiary PICU. Nasopharyngeal aspirates (NPA) from 229 children admitted to PICU with an ARI were analysed. RV was the most common virus detected, being present in 94 (41.0%) of samples examined, followed by respiratory syncytial virus (RSV) which was identified in 50 (21.8%) samples. A subsection analysis of cases with residual sample available of sufficient quality to allow for RV species typing showed that overall, the percentage of PICU admissions for each RV species was 22.3% for RV-C, 17.5% for RV-A and 1.7% for RV-B. This study demonstrated that RV is the most frequent virus identified in children admitted to a tertiary PICU with an ARI and RV-C is the most common RV species detected. Importantly, in the children admitted to PICU with an ARI, RV-C was by itself as common a pathogen as RSV.

© 2018 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd. Background: Significant differences exist in the prevalence, spectrum, and severity of allergic diseases between developing and developed countries and between subpopulations within single countries. These discrepancies likely result from a complex interaction between genetic and environmental factors. However, the precise nature of the contribution of ethnicity to genetic differences in the predisposition to allergic disease is not yet fully understood. In particular, there is a paucity of literature regarding the genetic determinants of allergic disease in people of black African origin with little or no genetic admixture. Objective: We aimed to analyze associations between 27 single nucleotide polymorphisms (SNPs) and allergy phenotypes in the local Xhosa population. Methods: A convenience sample of 213 Xhosa teenagers was enrolled at a local high school. Phenotypic data were collected in the form of a symptom questionnaire, skin prick tests for common food and aeroallergens, total serum IgE, and IgE to Ascaris lumbricoides. In addition, genotyping was performed to establish the prevalence of putative pro-inflammatory alleles. Results: We demonstrated several significant associations between polymorphisms and allergy phenotypes. In particular, 2 polymorphisms in the IL-10 gene (IL10 -592A > C and IL10 -1082A > G) and 1 in the IL-4 gene (IL4 -589C > T) showed multiple associations with allergic sensitization and asthma phenotypes. Other polymorphisms, across a multitude of genes with discrepant fu nctions, showed less consistent associations. Conclusion: This study represents an important first step in genotype/phenotype association in this population. Further research is required to confirm or refute our findings.

© 2018 Wiley Periodicals, Inc. Introduction: Increasing evidence suggests that poor lung function in adulthood is determined very early in life. Our study aims were: (1) identify factors associated with early infant lung function; (2) quantify the link between early infant lung function and early adult lung function; and (3) identify environmental and inherited factors which predict lung function throughout the post-natal growth period. Methods: In this longitudinal study, 253 individuals were recruited antenatally. Lung function and allergy testing occurred at 1, 6, 12 months, 6, 11, 18, and 24 years of age. The relationship between lung function at 1 month (V'maxFRC) and spirometry variables at each follow-up was evaluated. Early life predictors of spirometry were assessed longitudinally using linear mixed models. Results: V'maxFRC correlated positively with FEF25-75% at every assessment from 6 to 24 years and FEV 1 /FVC at 11 and 24 years and inversely with airway responsiveness at 6 and 18 years. Maternal asthma and smoking in pregnancy were associated with lower FEV 1 from 6 to 24 years (-99mL, P=0.03; -77mL, P=0.045 respectively). Lower V'maxFRC at 1 month was associated with asthma and wheeze through to 24 years. Conclusion: Lung airflow measurements track from birth into early adulthood, suggesting a permanent and stable airway framework is laid down in the antenatal period. Lower infant airway function is associated with respiratory symptoms into adulthood, indicating the link is clinically important. Antenatal and early life exposures must be addressed in order to maximize airway growth and reduce lifelong respiratory compromise.

Background: Hundreds of genetic variants are thought to contribute to variation in asthma risk by modulating gene expression. Methods that increase the power of genome-wide association studies (GWASs) to identify risk-associated variants are needed. Objective: We sought to develop a method that aggregates the evidence for association with disease risk across expression quantitative trait loci (eQTLs) of a gene and use this approach to identify asthma risk genes. Methods: We developed a gene-based test and software package called EUGENE that (1) is applicable to GWAS summary statistics; (2) considers both . cis- and . trans-eQTLs; (3) incorporates eQTLs identified in different tissues; and (4) uses simulations to account for multiple testing. We applied this approach to 2 published asthma GWASs (combined n = 46,044) and used mouse studies to provide initial functional insights into 2 genes with novel genetic associations. Results: We tested the association between asthma and 17,190 genes that were found to have . cis- and/or . trans-eQTLs across 16 published eQTL studies. At an empirical FDR of 5%, 48 genes were associated with asthma risk. Of these, for 37, the association was driven by eQTLs located in established risk loci for allergic disease, including 6 genes not previously implicated in disease cause (eg, . LIMS1, . TINF2, and . SAFB). The remaining 11 significant genes represent potential novel genetic associations with asthma. The association with 4 of these replicated in an independent GWAS: . B4GALT3, . USMG5, . P2RY13, and . P2RY14, which are genes involved in nucleotide synthesis or nucleotide-dependent cell activation. In mouse studies, P2ry13 and P2ry14-purinergic receptors activated by adenosine 5-diphosphate and UDP-sugars, respectively-were upregulated after allergen challenge, notably in airway epithelial cells, eosinophils, and neutrophils. Intranasal exposure with receptor agonists induced the release of IL-33 and subsequent eosinophil infiltrati

BACKGROUND: The major trigger of asthma exacerbations is infection with a respiratory virus, most commonly rhinovirus. Type 2 inflammation is known to be associated with an increased risk of exacerbations in general. Whether type 2 inflammation at baseline increases the risk of future virus-induced exacerbations is unknown.OBJECTIVE: To assess whether type 2 inflammation is associated with an increased risk of virus-induced exacerbations of asthma.METHODS: Stable asthmatics had spirometry, skin prick test, measurement of FeNO and sputum induced for differential cell counts. Patients were followed up for 18 months, during which they were assessed at the research unit when they had symptoms of an exacerbation. Nasal swabs collected at these assessments underwent viral detection by PCR.RESULTS: A total of 81 asthma patients were recruited, of which 22 (27%) experienced an exacerbation during the follow-up period. Of these, 15 (68%) had a respiratory virus detected at exacerbation. Sputum eosinophils >1% at baseline increased the risk of having a subsequent virus-induced exacerbation (HR 7.6 95% CI: 1.6-35.2, P=.010) as did having FeNO >25 ppb (HR 3.4 95% CI: 1.1-10.4, P=.033).CONCLUSION AND CLINICAL RELEVANCE: Established type 2 inflammation during stable disease is a risk factor for virus-induced exacerbations in a real-life setting. Measures of type 2 inflammation, such as sputum eosinophils and FeNO, could be included in the risk assessment of patients with asthma in future studies.

Despite effective measles vaccines, measles still causes severe morbidity and mortality worldwide, particularly in developing countries. The Th2 pathway involving interleukin (IL)-4 and IL-13 cytokines, and their receptor IL-4Ra, play important roles in the Th1/Th2 balance and antibody production. A Th2 skewing of the cytokine milieu may affect vaccine responses. We investigated IL-4, IL-13, and IL-4Ra polymorphisms and their impact on measles IgG responses and measles vaccine failure, in two separate cohorts: 12-month-old Australian children immunized with measles-mumps-rubella vaccine (n?=?137) and a case/control cohort of children aged 6 months-14 years from Mozambique, Africa (n?=?89), some of whom were vaccinated, but still contracted measles (vaccine failure). We found that IL-4Ra haplotypes for Val75Ile, Ser503Pro, and Arg576Gln were associated with measles IgG in Mozambican children (p?=?0.016 and p?=?0.032 for Val.Pro.Arg and Val.Ser.Arg, respectively), but not Australian children. IL-4Ra 503Pro was more prevalent in Mozambique vaccine failure cases compared with controls (p?=?0.008). We showed that the impact of Th2 genes on measles vaccine responses differs between ethnicities and IL-4Ra polymorphisms may work in combination to affect measles antibody responses and vaccine failure in Mozambican children. Studies in this area are particularly important in developing countries like Mozambique where measles is still a major health issue.

Human rhinovirus (RV) is commonly associated with severe acute lower respiratory infections (ALRI) in children. We aimed to describe the distribution of RV species and associations between RV species and clinical features in children hospitalized with clinically severe pneumonia (CSP) in Morocco. Nasopharyngeal aspirates (NPAs) were collected from 700 children, 2-59 months of age, admitted with CSP to the Hôpital d'Enfants de Rabat in Morocco. At least one respiratory virus was identified in 92% of children, of which RV was the most common (53%). PCR assays, sequencing, and phylogenetic tree analyses were carried out on 183 RV-positive NPAs to determine RV species and genotypes. Of 157 successfully genotyped NPAs, 60 (38.2%) were RV-A, 8 (5.1%) were RV-B, and 89 (56.7%) were RV-C. Wheezing and cyanosis were more common in RV-C-positive than RV-A-positive children (80.9% vs. 56.7%; P?=?0.001 for wheezing and 10.1% vs. 0%; P?=?0.011 for cyanosis). Physician's discharge diagnosis of pneumonia was more frequent among RV-A-positive (40.0%) than RV-C-positive children (20.2%; P?=?0.009). RV-A and RV-C showed distinct seasonal patterns. Our findings suggest that RV-C is associated with wheezing illness while RV-A is associated with pneumonia. J. Med. Virol. 89:582-588, 2017. © 2016 Wiley Periodicals, Inc.

Background and objective: Asthma in adults is associated with a persistent reduction in lung function from childhood, but this link has not been assessed back to infancy. Reduced infant lung function (ILF), a measure of antenatal and infant lung growth, is associated with asthma into adolescence. Our aim was to assess whether this link persists into adulthood and whether ILF can predict the remission of asthma symptoms in young adults. Methods: The study cohort was an unselected full-term birth cohort of 253 subjects enrolled antenatally with lung function assessments at 1, 6 and 12months (maximum expiratory flow at functional residual capacity, V'maxFRC), and 6, 11, 18 and 24years (spirometry) of age. Results: Infants with V'maxFRC in the lowest quartile at 1month had an OR of 5.1 (95% CI: 2-13, P=0.001) for asthma at 24years. Subjects with asthma at 24years had a mean V'maxFRC at 1 month of 69% predicted (95% CI: 48-90%) versus 110% (95% CI: 101-119%) in non-asthmatic patients (P=0.001). Subjects with current versus resolved asthma symptoms at 24years had a mean V'maxFRC at 1month of 69% predicted (95% CI: 53-84%) versus 105% (88-123%), respectively (P=0.003). Subjects with current asthma at 24years had persistently lower lung function from infancy with a mean reduction of 16.2% (95% CI: 8.1-24.3%, P<0.0001). Conclusion: Reduced lung function in early infancy is predictive of persistent asthma in young adults and a persistent reduction in lung function, suggesting abnormal lung development and growth in utero or very early in life.

© 2016 John Wiley & Sons Ltd. Objectives: To describe the prevalence of human rhinovirus (RV) species in children hospitalised with pneumonia in Manhiça, Mozambique, and the associations between RV species and demographic, clinical and laboratory features. Methods: Nasopharyngeal aspirates were collected from children 0 to 10 years of age (n = 277) presenting to Manhiça District Hospital with clinical pneumonia. Blood samples were collected for HIV and malaria testing, blood culture and full blood counts, and a chest X-ray was performed. A panel of common respiratory viruses was investigated using two independent multiplex RT-PCR assays with primers specific for each virus and viral type. RV species and genotypes were identified by seminested PCR assays, sequencing and phylogenetic tree analyses. Results: At least one respiratory virus was identified in 206 (74.4%) children hospitalised with clinical pneumonia. RV was the most common virus identified in both HIV-infected (17 of 38, 44.7%) and HIV-uninfected (74 of 237, 31.2%; P = 0.100) children. RV-A was the most common RV species identified (47 of 275, 17.0%), followed by RV-C (35/275, 12.6%) and RV-B (8/275, 2.9%). Clinical presentation of the different RV species was similar and overlapping, with no particular species being associated with specific clinical features. Conclusions: RV-A and RV-C were the most common respiratory viruses identified in children hospitalised with clinical pneumonia in Manhiça. Clinical presentation of RV-A and RV-C was similar and overlapping.

© 2016, Springer-Verlag Berlin Heidelberg. The importance of good device technique to maximise delivery of aerosolised medications is widely recognised. Pressurised metered dose inhaler (pMDI)-spacer technique was investigated in 122 children, aged 2–7 years, w ith asthma. Eight individual steps of device technique were evaluated before and after viewing an instructional video for correct device technique. Video measurements were repeated every three months for nine months. Device technique improved directly after video instruction at the baseline study visit (p < 0.001) but had no immediate effect at subsequent visits. Additionally, pMDI-spacer technique improved with successive visits over one year for the group overall as evidenced by increases in the proportion of children scoring maximal (p = 0.02) and near-maximal (p = 0.04) scores. Conclusion: Repeated video instruction over time improves inhaler technique in young children.What is Known:• Correct device technique is considered essential for sufficient delivery of inhaled medication.• Poor inhaler use is common in young asthmatic children using pressurised metered dose inhalers and spacers.What is New:• Video instruction could be used as a strategy to improve device technique in young children.

© 2016 Elsevier B.V..Background: Human rhinovirus (RV) is the most common respiratory virus and has been associated with frequent and severe acute lower respiratory infections (ALRI). The prevalence of RV species among HIV-infected children in South Africa is unknown. Objectives: To describe the prevalence of respiratory viruses, including RV species, associated with HIV status and other clinical symptoms in children less than two years of age with and without ALRI in Pretoria, South Africa. Study design: Nasopharyngeal aspirates were collected from 105 hospitalized ALRI cases and 53 non-ALRI controls less than two years of age. HIV status was determined. Common respiratory viruses were identified by PCR, and RV species and genotypes were identified by semi-nested PCR, sequencing and phylogenetic tree analyses. Results: Respiratory viruses were more common among ALRI cases than controls (83.8% vs. 69.2%; p = 0.041). RV was the most commonly identified virus in cases with pneumonia (45.6%) or bronchiolitis (52.1%), regardless of HIV status, as well as in controls (39.6%). RV-A was identified in 26.7% of cases and 15.1% of controls while RV-C was identified in 21.0% of cases and 18.9% of controls. HIV-infected children were more likely to be diagnosed with pneumonia than bronchiolitis (p < 0.01). RSV was not identified in any HIV-infected cases (n = 15) compared with 30.6% of HIV-uninfected cases (n = 85, p = 0.013), and was identified more frequently in bronchiolitis than in pneumonia cases (43.8% vs. 12.3%; p < 0.01). Conclusions: RV-A and RV-C are endemic in South African children and HIV infection may be protective against RSV and bronchiolitis.

The Perth Infant Asthma Follow-up (PIAF) study involves a birth cohort of unselected subjects who have undergone longitudinal assessments of airway responsiveness at 1, 6 and 12 months and 6, 11 and 18 years of age. The aim of this study was to determine the relationship between increased airway responsiveness throughout childhood and asthma in early adult life. Airway responsiveness to histamine, assessed as a dose–response slope (DRS), and a respiratory questionnaire were completed at 1, 6 and 12 months and 6, 11 and 18 years of age. 253 children were initially recruited and studied. Airway responsiveness was assessed in 203, 174, 147, 103, 176 and 137 children at the above-mentioned time points, respectively (39 participants being assessed on all test occasions). Asthma at 18 years was associated with increased airway responsiveness at 6, 12 and 18 years, but not during infancy (slope 0.24, 95% CI 0.06–0.42; p=0.01; slope 0.25, 95% CI 0.08–0.49; p=0.006; and slope 0.56, 95% CI 0.29–0.83; p<0.001, respectively). Increased airway responsiveness and its association with asthma at age 18 years is established between infancy and 6 years. We propose that airway responsiveness in early life reflects the initial airway geometry and airway responsiveness later in childhood increasingly reflects immunological responses to environmental influences.

Measles virus causes severe morbidity and mortality, despite the availability of measles vaccines. Successful defence against viral pathogens requires early recognition of virus-specific patterns by innate receptors like Toll-like receptor (TLR)3 and the RNA helicase, retinoic acid inducible gene-I (RIG-I). Genetic differences in these receptors may influence the primary immune responses to measles and the efficacy of measles vaccine. In 1-year-old Australian infants after their first measles vaccine dose, we investigated functional effects of TLR3 and RIG-I polymorphisms on intracellular protein expression using flow cytometry, cytokine responses to receptor ligands and measles lysate, and post-vaccination measles IgG levels. We found that TLR3 Leu412Phe was significantly associated with IFN-a/ß response after stimulation with TLR3 ligand, poly(I:C) (P= 0.024). Downregulation of TLR3 protein expression in NK cells after poly(I:C) was also associated with this variant (P= 0.011). In contrast, measles-specific expression, cytokine responses and antibody responses were not associated with TLR3 polymorphisms. No associations were found with RIG-I variants. These results suggest that a TLR3 polymorphism has functional effects on receptor expression and cytokine response. However, this did not translate to an effect on specific responses to measles virus or vaccine. We found no evidence that RIG-I polymorphisms were involved in measles immune responses. © 2012.

Despite an effective vaccine, measles remains a major health problem globally, particularly in developing countries. More than 30% of children show primary vaccine failure and therefore remain vulnerable to measles. Genetic variation in key innate pathogen recognition receptors, such as the measles cell entry receptors CD46 and SLAM, measles attachment receptor DC-SIGN, the antiviral toll-like receptors (TLR)3, TLR7 and TLR8, and the cytosolic antiviral receptor RIG-I, may significantly affect measles IgG antibody responses. Measles is still highly prevalent in developing countries such as those in Africa however there is no previous data on the effect of these innate immune genes in a resident African population. Polymorphisms (n= 29) in the candidate genes were genotyped in a cohort of vaccinated children (n= 238) aged 6 months-14 years from Mozambique, Africa who either had vaccine failure and contracted measles (cases; n= 66) or controls (n= 172). Contrasting previous associations with measles responses in Caucasians and/or strong evidence for candidacy, we found little indication that these key innate immune genes affect measles IgG responses in our cohort of Mozambican children. We did however identify that CD46 and TLR8 variants may be involved in the occurrence of measles vaccine failure. This study highlights the importance of genetic studies in resident, non-Caucasian populations, from areas where determining the factors that may affect measles control is of a high priority. © 2012 Elsevier Ltd.

Despite the availability of measles vaccines, infants continue to die from measles. Measles vaccine responses vary between individuals, and poor immunogenicity is likely to preclude protection against measles. CD46 is a ubiquitously expressed specific receptor for vaccine strains of measles virus. CD46 polymorphisms have not been functionally investigated but may affect CD46 protein expression, which in turn may mediate primary measles antibody responses in infants. In a cohort of children aged 12 to 14 months from Perth, Australia (n=137), after their first dose of measles-mumps-rubella (MMR) vaccine, CD46 polymorphisms were genotyped, and postvaccination measles IgG and CD46 protein expression before and after measles lysate stimulation of cells were measured. Three CD46 variants (rs7144, rs11118580, and rs2724384) were significantly associated with measles virus-specific IgG levels (P=0.008, P=0.026, and P=0.018, respectively). There were significant differences between CD46 rs7144 genotypes and CD46 protein expression on T cells, as well as the downregulation of CD46 and T-cell frequency after measles lysate stimulation. We show that CD46 polymorphisms were associated with primary measles antibody responses in naive infants. We also report the first association of a measles virus receptor polymorphism with functional effects on the receptor, suggesting a possible mechanism through which antibody responses are altered. Elucidating all of the interconnecting genetic factors that alter primary measles vaccine responses may be important for identifying children at risk of poor immunogenicity or vaccine failure and for the future design of vaccine strategies to help these children. Copyright © 2012, American Society for Microbiology.

Background: Adherence to prescribed inhaled medication is often low in young children. Poor adherence to medication may contribute to lack of symptom control. Doctors are not good at predicting the adherence rates of their patients, and parental report of adherence does not correlate with objective measures of adherence. The objective of this study was to investigate whether parental admission of non-adherence and reasons given for non-adherence correlated with objectively measured adherence. Methods: Adherence to prescribed inhaled corticosteroid treatment was monitored electronically in 132 children aged 2-6 years who were participating in a randomised controlled trial comparing different inhaler devices. Follow-up was carried out every 3 months for a year. Parental answers to simple questions about adherence were compared to electronically measured adherence. Results: Mean adherence ranged from zero to 100%. Intraparticipant adherence varied throughout the year-long study period (mean variance for individual children between quarterly periods was 28.5%). Parents who reported missed doses, generally missed at least half of the prescribed doses. Parents who reported that not a single prescribed dose was missed, still missed 20% of doses on average. Adherence was particularly low when parents cited initiating their own trial off medication as a reason for missing doses. Conclusions: By examining parental response to questions enquiring whether any doses were missed, healthcare providers can gain a modest degree of insight into their patients' true adherence to prescribed medication. Adherence to prescribed asthma medication is extremely variable in young children. Trial registration number: Data from this study were derived from a randomised controlled trial (ACTRN12608000294358).

Successful defence against viral pathogens requires the rapid recognition of virus-specific "danger signals" and the activation of both innate and adaptive immunity. Toll-like receptors (TLR) 7 and 8 play a critical role in the elimination of viruses by recognising the common viral component, single stranded (ss)RNA. Measles virus, an ssRNA virus, continues to cause serious morbidity and mortality worldwide despite available measles vaccines. TLR7 and TLR8 genetic variation may cause functional alterations that result in impaired responses to measles. In a population of 12-month-old Australian infants, receptor protein expression was examined to assess the functionality of TLR7 and TLR8 polymorphisms, and the effects of these polymorphisms on cellular and antibody responses after the first measles vaccine dose were investigated. TLR7 Leu11Gln showed associations with TNF-a responses after ligand (imiquimod) stimulation in males only (P = 0.040), and non-responders were more likely to be Gln males (P = 0.044). TNF-a non-responders after imiquimod also had higher percentages of TLR8 -4284TT (69.6%) (P = 0.001) and TLR8 -558CC (69.6%) (P = 0.002) in females. Receptor protein expression after imiquimod or measles stimulation was not significantly altered compared with baseline, nor was it affected by genotype. None of the TLR7 or TLR8 polymorphisms studied were associated with measles-specific cytokine levels or with measles IgG levels. In conclusion, we report gender-specific associations with TLR7 and TLR8 polymorphisms and TNF-a cellular responses to its ligand. However, we found no evidence of any functional effects of TLR7 or TLR8 polymorphisms on receptor expression, measles-specific cellular responses or measles vaccine antibody responses. © 2011 Springer-Verlag.

Objective: To examine the influence of viral respiratory infection (VRI) on treatment response in acute asthma in children. Study design: A total of 218 children (mean age, 6.6 years) with acute asthma were recruited. Symptoms were recorded, an asthma severity score was determined, and whenever possible, a per-nasal aspirate was obtained for detection of viruses. Each child's response to inhaled ß 2-agonists was assessed after 6, 12, and 24 hours. Results: The 168 children with VRI symptoms received more treatment with inhaled ß 2-agonists after 6 hours (P = .010), 12 hours (P =.002), and 24 hours (P =.0005) compared with the 50 children without such symptoms. Asthma severity did not differ between the 2 groups. A per-nasal aspirate was obtained from 77% of the children. The most frequently identified virus was rhinovirus (61.4%). Among children with symptoms of a VRI, those with rhinovirus had an impaired response to ß 2-agonists at 6 hours (P =.032). Conclusion: Children with acute asthma and symptoms of VRI respond less effectively to ß 2-agonists after 6, 12, or 24 hours and thus may benefit from more intense therapy and monitoring. Copyright © 2012 Mosby Inc. All rights reserved.

A new and potentially more pathogenic group of human rhinovirus (HRV), group C (HRVC), has recently been discovered. We hypothesised that HRVC would be present in children with acute asthma and cause more severe attacks than other viruses or HRV groups. Children with acute asthma (n=128; age 2-16 yrs) were recruited on presentation to an emergency department. Asthma exacerbation severity was assessed, and respiratory viruses and HRV strains were identified in a nasal aspirate. The majority of the children studied had moderate-to-severe asthma (85.2%) and 98.9% were admitted to hospital. HRV was detected in 87.5% and other respiratory viruses in 14.8% of children, most of whom also had HRV. HRVC was present in the majority of children with acute asthma (59.4%) and associated with more severe asthma. Children with HRVC (n=76) had higher asthma severity scores than children whose HRV infection was HRVA or HRVB only (n=34; p=0.018), and all other children (n=50; p=0.016). Of the 19 children with a non-HRV virus, 13 had HRV co-infections, seven of these being HRVC. HRVC accounts for the majority of asthma attacks in children presenting to hospital and causes more severe attacks than previously known HRV groups and other viruses. Copyright©ERS 2011.

Despite the use of measles vaccine, measles virus continues to circulate and cause severe disease. Immune responses to the measles vaccine are variable between individuals, with up to 10% failing to produce a sufficient protective response post-vaccination. Signaling lymphocyte activation molecule (SLAM) and dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN; CD209) are specific measles receptors: SLAM binds and permits entry of the virus into the cell, DC-SIGN acts as an attachment receptor, increasing viral binding efficiency and transmission. Genetic variations in these receptor genes may alter measles vaccine antibody and cellular responses. Methods: In 12-month-old infants from Perth, Western Australia after their first measles vaccine dose as part of the combination measles-mumps-rubella (MMR) vaccine, 7 SLAM and DC-SIGN polymorphisms were genotyped and associations were investigated with measles IgG antibody levels and in vitro measles cytokine responses. Results: The DC-SIGN promoter variant -336C/T was associated with overall IFN-? responses after measles stimulation (P= 0.002) and three DC-SIGN polymorphisms (-336C/T, -139C/T and -871C/T) were associated with the proportion of cytokine non-responders to measles (P= 0.001, P= 0.021 and P= 0.036, respectively). However, no associations were found between the DC-SIGN or SLAM polymorphisms and measles IgG antibody levels. Conclusions: The results suggest that DC-SIGN -139C/T, -336C/T and -871C/T polymorphisms may modulate cytokine (but not antibody) responses to the measles component of MMR vaccine. Furthermore, contrasting previous studies, SLAM polymorphisms do not appear to affect measles antibody or cytokine responses in this cohort. © 2011.

Genetic and environmental influences and their interactions are central to asthma pathogenesis. This study aimed to investigate the effects of different macro-environments on asthma genotype-phenotype associations in two geographically separated populations with common ancestry.

OBJECTIVE: The goal was to determine the number of breaths required to inhale salbutamol from different spacers/valved holding chambers (VHCs). METHODS: Breathing patterns were recorded for 2- to 7-year-old children inhaling placebo from 4 different spacers/VHCs and were simulated by a flow generator. Drug delivery with different numbers of tidal breaths and with a single maximal breath was compared. RESULTS: With tidal breathing, mean inhalation volumes were large, ranging from 384 mL to 445 mL. Mean values for drug delivery with an Aerochamber Plus (Trudell, London, Canada) were 40% (95% confidence interval [CI]: 34%-46%) and 41% (95% CI: 36%-47%) of the total dose with 2 and 9 tidal breaths, respectively. Mean drug delivery values with these breath numbers with a Funhaler (Visiomed, Perth, Australia) were 39% (95% CI: 34%-43%) and 38% (95% CI: 35%-42%), respectively. With a Volumatic (GlaxoSmithKline, Melbourne, Australia), mean drug delivery values with 2 and 9 tidal breaths were 37% (95% CI: 33%-41%) and 43% (95% CI: 40%-46%), respectively (P = .02); there was no significant difference in drug delivery with 3 versus 9 tidal breaths. With the modified soft drink bottle, drug delivery. Drug delivery was not improved with a single maximal breath with any device. CONCLUSION: For young children, tidal breaths through a spacer/VHC were much larger than expected. Two tidal breaths were adequate for small-volume VHCs and a 500-mL modified soft drink bottle, and 3 tidal breaths were adequate for the larger Volumatic VHC. Copyright © 2010 by the American Academy of Pediatrics.

Rationale: Xenobiotics in the maternal circulation are capable of crossing the placental barrier so a reduction in the mother and fetus's detoxification ability due to genetic variation in the glutathione S-transferases (GSTs) could expose the fetus to higher levels of toxins. Objectives: To investigate the interactive effects of maternal smoking during pregnancy with maternal and infant GST genotypes on airway responsiveness (AR) and lung function in infancy. Methods: GSTT1, GSTP1 and GSTM1 were genotyped in infants and mothers, in utero smoke exposure was evaluated by questionnaire, AR was assessed by histamine challenge and V?maxFRC was measured using the rapid thoracoabdominal compression technique. We investigated the interactive effects of maternal smoking during pregnancy with maternal and infant GST genes on AR and lung function at 1, 6, and 12 months and longitudinally throughout the first year. Measurements and Main Results: Infant and/or maternal GSTT1 nonnull was associated with reduced AR at 12 months and throughout the first year and increased V?maxFRC at 6 months. Maternal GSTP1 Val/Val or Ile/Val was associated with increased V?maxFRC at 6 months. In infants exposed to in utero smoke, infant and/or maternal GSTT1 nonnull was associated with reduced AR at 1 month and throughout the first year and increased V?maxFRC throughout the first year. Maternal GSTP1 Val/Val or Ile/Val was associated with increased V?maxFRC at 6 months. Conclusions: GST genes may be especially important during fetal development as they may modify, through proficient detoxification, the effects of in utero maternal smoke exposure on AR and lung function in infants.

Background: Output from spacers (or valved holding chambers) is sensitive to changes in breathing pattern. Different spacers have unique characteristics that may influence breathing. A method used for breathing simulation, where the simulated breathing can be recorded on subjects while they are using spacers, may allow for more accurate in vitro estimation of drug delivery in specific populations, using specific spacers. Methods: A flow chamber was used to record breathing while salbutamol was administered to two adult subjects through different spacers. Each subject performed a series of breathing patterns over a range of different inhalation volumes and flows. Salbutamol "inhaled" by subjects was captured on inspiratory filters and quantified by ultraviolet spectrophotometry. Recorded breathing patterns were simulated and ex vivo drug delivery was compared to in vitro drug delivery. Three equipment configurations were used to validate different aspects of the methodology. Configuration 1: breathing recorded by pneumotachometer placed directly between a human subject and the spacer. Breathing simulation performed with an identical setup. Configuration 2: spacer enclosed within a flow-chamber while breathing was recorded. Breathing simulation performed with an identical setup. Configuration 3: spacer enclosed in flow chamber to record breathing, but not when simulating breathing. In each configuration, the ex vivo and in vitro (simulated) filter doses were compared. Results: Configuration 1: the median difference between ex vivo and in vitro filter doses was 0.4% (range: -12.2 to 6.9%). Configuration 2: the median difference was -2.3% (range: -9.0 to 5.0%). Configuration 3: the median difference was 1.7% (range: -11.5 to 3.9%). Conclusion: Our results indicate that in vitro simulated drug delivery using this method of recording using a flow chamber, closely approximates ex vivo total drug delivery. This technique allows for recording of breathing on patients while t

Background: Genetic and environmental influences and their interactions are central to asthma pathogenesis. This study aimed to investigate the effects of different macro-environments on asthma genotype-phenotype associations in two geographically separated populations with common ancestry. Methods: To accomplish this, two unselected populations of Inuit were recruited, one living in Greenland (n = 618) and the other in Denmark (n = 739). Subjects were genotyped for CD14 C-159T, SCGB1A1 A38G, ADRB2 Arg16Gly and Gln27Glu. The resulting genetic data were analysed for relationships with asthma-related parameters including lung function, ever asthma, atopy, rhinitis and dermatitis. Results: The results showed contrasting magnitude and direction of genetic associations between the two geographically separate Inuit populations. In Greenland, the ADRB2 16Arg allele was associated with male-specific lower lung function, but in Denmark the same allele was associated with male-specific higher lung function. This allele was also associated with higher incidence of ever asthma in Denmark but not in Greenland. The SCGB1A1 38A allele was associated with lower rhinitis prevalence in Greenland but not in Denmark. Conclusions: These associations suggest that environment interacts with candidate asthma genes to modulate asthma pathogenesis in the Inuit. © 2009 John Wiley & Sons A/S.

The ST2 gene is a member of the interleukin-1 receptor family and is located on chromosome 2q12, an area of the genome that has been associated with asthma. The soluble product of the ST2 gene, serum ST2 (sST2), has previously been shown to be elevated in adult asthmatic patients. This study investigated the potential role of ST2 in children with acute asthma. Children aged 2-16 years (n = 186) were recruited on presentation with acute asthma in the emergency department. Blood was obtained on presentation and during convalescence. Variables assessed included sST2 levels, a comprehensive assembly of clinical parameters and two polymorphisms in the ST2 gene, -26999G/A, located in the distal promoter region, and ala78glu polymorphism, on exon 3. The A allele of the -26999G/A polymorphism occurred more frequently in asthmatics compared with an unselected control group (P = 0.031). Serum ST2 levels were substantially higher during acute asthma compared with levels after the attack: 0.29 ng/ml (95% confidence interval: 0.23-0.36) and 0.14 ng/ml (0.12-0.17), respectively (P = 0.001) and were inversely related to eosinophil counts during an acute asthma attack (P = 0.002). The -26999AA genotype, as well as the AC haplotype, was associated with asthma severity scores (P = 0.05 and 0.02) compared with the -26999GA and GG genotypes. Serum ST2 levels were not associated with any of the studied genotypes or haplotypes. The observed associations of ST2 genotypes and haplotypes with acute asthma and asthma severity scores as well as the phenotypic differences associated with ST2 polymorphisms suggest that ST2 may play a role in the pathophysiology of asthma. © 2009 John Wiley & Sons A/S.

Background: Finnish Karelians have a higher prevalence of allergic disease than Russian Karelians. As both populations are generally from the same ethnic group, the Karelian population offers a unique opportunity to analyse genetic and allergic disease interactions between 'Western' and 'Eastern' environments. Objectives: We investigated associations between allergic diseases and CD14 and CC16 polymorphisms in Finnish vs Russian Karelian women. Methods: Adult female Karelians (330 Finnish and 274 Russian) were recruited, examined for a range of symptoms and conditions including rhinitis, itchy rash, asthma and atopy and genotyped for CD14 C-159T and CC16 A38G. Results: For both CD14 C-159T and CC16 A38G, the risk allele for atopic phenotypes in Finnish Karelia was the protective allele in Russian Karelia. For CD14 C-159T, an interactive effect on ever itchy rash (Pinteraction = 0.004), itchy rash <12 mo (P interaction = 0.001) and dry cough at night in the past 12 months (<12 months) (Pinteraction = 0.011) was found; the risk allele was C in Russians and T in Finns. For CC16 A38G, an interaction was significant for ever rhinitis (Pinteraction = 0.006), rhinitis <12 mo (P interaction = 0.004), and marginally significant for ever hayfever (Pinteraction = 0.07), allergic eye symptoms <12 mo (P interaction = 0.09); their risk allele was G in Russians and A in Finns. Conclusion: An Eastern vs Western environment appears to exert an effect via opposite alleles on risk of allergic diseases in adult women. © 2009 John Wiley & Sons A/S.

Cysteinyl leukotrienes (cysLTs) are pro-inflammatory mediators with increasing evidence for a role in childhood acute asthma. This study examined the influence of polymorphisms in cysLT pathway genes on urinary leukotriene E4 (uLTE4) levels and clinical status in acute asthmatic children. Children aged 2-16 years were recruited during an asthma attack (n=205). Where possible, asthma severity scores were assigned, ALOX5AP G-336A, ALOX5 G-1708A, LTC4S A-444C and G-1072A, GPX4 C718T, and CYSTLTR1 T927C genotypes were determined and uLTE4 was measured in acute and convalescent samples. uLTE4 levels were higher acutely compared with convalescence (acute GM: 115.7 pg/mg creatinine; 95% CI 88.6-151.1, convalescence GM: 66.4 pg/mg creatinine; 95% CI 51.5-85.6; n=50 paired samples, p=0.003) and paired sample analysis showed genotype-specific effects with significantly increased uLTE4 for LTC4S-444AA (acute GM: 127.9 pg/mg creatinine; 95% CI 91.8-178.3, convalescence GM: 68.2 pg/mg creatinine; 95% CI 50.5-92.0; n=32, p=0.002), LTC4S-1072 GG (acute GM: 126.7 pg/mg creatinine; 95% CI 95.4-168.3, convalescence GM: 78.9 pg/mg creatinine; 95% CI 59.7-104.1; n=39, p=0.019) and CYSLTR1 927 TT/T_ (acute GM: 96.8 pg/mg creatinine; 95% CI 73.8-126.9, convalescence GM: 62.4 pg/mg creatinine; 95% CI 46.8-83.3; n=28, p=0.036) but not AC/CC, GA/AA, or TC/CC/C_, respectively. When we compared the allele frequencies of the CYSLTR1 SNP between asthmatics and non-asthmatics, the 927C allele was found to be a risk allele for asthma (OR=2.13, 95% CI: 1.06-4.26, p=0.033). Genotypes were not associated with acute or convalescent uLTE4 levels alone and neither the SNPs nor uLTE4 correlated with acute asthma severity. Leukotriene pathway gene polymorphisms may influence the magnitude of cysLT production during an attack, yet their influence alone may not be substantial enough to alter the severity of exacerbations. © 2009 Elsevier Ltd. All rights reserved.

Background: A study was undertaken to examine factors that might influence lung function during infancy and to test the hypothesis that change in weight during infancy is negatively associated with change in lung function. Methods: Weight, length and maximal flow at functional residual capacity (V'maxFRC) were measured at ages 1 and 12 months. V'maxFRC was adjusted for length. Asthma symptoms and age at introduction of formula feeds were identified from questionnaires. Groups were dichotomised by V'maxFRC at 1 month and change in V'maxFRC. Results: 154 infants were assessed at ages 1 and 12 months. The change in V'maxFRC was inversely associated with change in weight (r = -0.18, r2 = 0.13, p<0.001). The group with lower V'maxFRC at 1 month and reduced change in V'maxFRC over infancy had the greatest weight gain (p = 0.003) and increased risk for asthma symptoms by 3 years (p = 0.017) but not afterwards. Exclusive breast feeding to 6 months was associated with a mean reduction in weight gain at age 12 months in comparison with earlier introduction of formula milk (mean difference 0.65 kg, p = 0.001), and was also associated with reduced asthma symptoms at 3 years (odds ratio 0.44, p = 0.043) but not at 6 or 11 years of age. Conclusions: Weight gain in infancy is inversely associated with change in lung function during infancy. Postnatal weight gain may be indirectly associated with early transient asthma symptoms via an influence on lung growth during infancy, and this is potentially modifiable by breast feeding. These associations could be relevant to the clinically recognised syndrome of the "fat happy wheezer".

The aim of this study was to determine the influence of single nucleotide polymorphisms in the ß2-adrenoceptor gene, on the response to inhaled ß2-agonists in children with acute asthma. We hypothesised that children with polymorphisms that generate enhanced receptor downregulation in vitro, Gly16 and Gln27, would have a slower response to ß2-agonist therapy during acute asthma. One hundred and forty-eight children with acute asthma were recruited and genotyped for ß2Arg16Gly and ß2Gln27Glu. For Gln27Glu, individuals Gln27Gln took longest to stretch out to 1, 2 and 4 hourly ß2-agonists, followed by heterozygotes who were intermediate and Glu27Glu who responded most rapidly (1hourly: 2.6hr vs. 2.0 vs. 1.4, p = 0.02; 2 hourly: 10.6hr vs. 10.7 vs. 6.8, p = 0.07; 4 hourly: 29.8hr vs. 28.5 vs. 24.3, p = 0.30). The ability to prospectively identify children who respond less effectively to ß 2-agonists during an acute asthma attack has the potential to allow the generation of genotype-specific treatment pathways. Copyright © 2008 Informa Healthcare USA, Inc.

Cytokine gene polymorphisms affect vaccine responses and gender-specific effects are known for many phenotypes. Therefore, this study investigated gender-specific effects of cytokine gene polymorphisms on vaccine responses. In 263 2-year-old subjects selected for parental history of atopy, boys with IL-4 C-589T and IL-4Ra I50V genotypes associated with atopy had increased Diptheria Toxoid (DiphTox) and Tetanus Toxoid (TetTox) responses compared with the remaining alleles (IL-4 C-589T: DipTox p = 0.01, TetTox p = 0.04; IL-4Ra.I50V: DipTox p = 0.04, TetTox p = 0.08). Contrastingly, girls with IL-10 -592C genotypes associated with atopy had lower levels of DiphTox (p = 0.03) and TetTox (p = 0.02) responses compared with the remaining allele. Additionally, interaction effects were found for IL-4 C-589T (p = 0.01) and IL-4Ra I50V (p = 0.04) polymorphisms. In conclusion, these findings support the interaction of primary genetic and modifying factors on vaccine responses and the importance of atopic genetics to these responses. © 2008 Elsevier Ltd. All rights reserved.