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Coronaviruses (CoVs) were first discovered in the 1960s. Severe acute respiratory syndrome CoV-2 (SARS-CoV-2) has been identified as the cause of COVID-19, which spread throughout China and subsequently, across the world. As COVID-19 causes serious public health concerns across the world, investigating the characteristics of SARS-CoV-2 and its interaction with the host immune responses may provide a clearer picture of how the pathogen causes disease in some individuals. Interestingly, SARS-CoV-2 has 80% sequence homology with SARS-CoV-1 and 96–98% homology with CoVs isolated from bats. Therefore, the experience acquired in SARS and Middle East Respiratory Syndrome (MERS) epidemics may improve our understanding of the immune response and immunopathological changes in COVID-19 patients. In the present paper, we have reviewed the immune responses (including the innate and adaptive immunities) to SARS-CoV, MERS-CoV, and SARS-CoV-2, so as to improve our understanding of the concept of the COVID-19 disease, which will be helpful in developing vaccines and medications for treating the COVID-19 patients. [ABSTRACT FROM AUTHOR]

Introduction: Chicken eggs and cow's milk are two of the most common foods that cause allergic reactions in infants and young children, and there is a lack of precise diagnostic methods to identify the allergic state of these patients. The recently developed food allergen component-resolved diagnosis (CRD) may be a more accurate diagnosis method for food allergies. Methods: One hundred children sensitized to egg white and milk crude extracts and diagnosed with or suspected allergic disease were included. The specific immunoglobulin E (sIgE) (s) of animal food allergen crude extracts (egg yolk, milk, shrimp, crab, cod, beef) and the main components of egg white and milk were tested. The sensitization characteristics, cross-reactivity, and clinical relevance were analyzed. Results: The results of egg white-sensitized patients showed that ovalbumin (Gal d 2) had the highest positive rate of 100%. Compared with other pairwise combinations of egg allergens, the combination of egg white and Gal d 2 had higher diagnostic accuracy, with an AUC of 0.876 (95% CI: 0.801–0.951), a sensitivity of 88.9%, and a specificity of 75.9%. The positive rates of beta-lactoglobulin (Bos d 5) and alpha-lactoglobulin (Bos d 4) in the milk-sensitized children were comparable, 92% and 91%, respectively. The combination of crude milk extract and Bos d 4 had the highest diagnostic accuracy, with an AUC of 0.969 (95% CI: 0.938–0.999), a sensitivity of 100%, and a specificity of 82.7%. Conclusion: Among these subjects, our study found the main allergenic component of egg white was Gal d 2, and the main allergenic components of milk were Bos d 4 and Bos d 5. CRD may help identify egg/milk allergies and non-allergies. [ABSTRACT FROM AUTHOR]

Introduction: Chronic rhinosinusitis with nasal polyps (CRSwNPs) in China is characterized by a mixed eosinophilic-neutrophilic inflammation, linking to a more heterogeneous clinical phenotype. However, the relationship between eosinophilic and neutrophilic inflammation in Chinese patients with CRSwNP remains largely unknown. We aimed to further characterize the correlation between neutrophils with eosinophils in relation to clinical characters and disease control status after endoscopic sinus surgery (ESS). Methods: A total of 242 patients were recruited and stratified based on tissue (≥10%) eosinophilia and (≥20/per high-power field) neutrophilia. Clinical characteristics and disease control status were compared between subgroups. Associations between tissue eosinophils and neutrophils were analyzed. Results: The uncontrolled patients accounted for 41.3%, 41.3%, 17.1%, and 22.2% in subjects with concomitant tissue eosinophilia and neutrophilia (EN-high), isolated eosinophilia (E-high), isolated neutrophilia (N-high), and no eosinophilia and neutrophilia (EN-low), respectively. Positive correlations between tissue eosinophils and neutrophils were observed in patients with CRSwNP as well as in EN-high and N-high subgroups but not in E-high and EN-low subgroups. The EN-high subgroup had higher tissue eosinophil numbers than the other three subgroups. Both EN-high and E-high subgroups had higher rates of uncontrolled subjects than the N-high and EN-low subgroups; however, there was no difference in the rate of uncontrolled subjects between EN-high and E-high subgroups and between N-high and EN-low subgroups. Conclusion: Tissue neutrophils might have a potential interaction and mutual promotion effect with eosinophils in CRSwNP. However, tissue neutrophilia would not pose significant risk for poor disease control after ESS. Further larger, prospective studies are needed to confirm our findings. [ABSTRACT FROM AUTHOR]

Introduction: Artemisia is a major kind of grass pollen in Northern China that can cause multiple kinds of common allergic diseases, such as allergic rhinitis (AR), conjunctivitis, or asthma. Recently, Artemisia annua Allergens Sublingual Immunotherapy Drops have been proved effective and safe for treating seasonal AR (SAR) with or without allergic conjunctivitis patients and were available in China. We sought to further investigate the different intervention times of A. annua-sublingual immunotherapy (SLIT) for evaluating efficacy and safety in patients with SAR. Methods: A total of 88 subjects aged 18–52 years with SAR were enrolled and randomized into the SLIT group and control group. Forty-five patients received a course of SLIT with A. annua extracts along with pharmacotherapy as SLIT group and 43 patients only used symptomatic drugs as control group. Furthermore, SLIT group was randomly divided into 12–13 weeks' pre-seasonal treatment group and 8–9 weeks' pre-seasonal treatment group to receive different duration of SLIT before pollen season. Monosensitized and polysensitized groups were also the subgroups of SLIT group according to the sensitization status of patients. The combined symptom and medication score (CSMS), total nasal symptom score (TNSS), total medication score (TMS), visual analog score (VAS) were evaluated during the peak pollen phase in 2020 and 2021, respectively. Safety was assessed according to adverse events (AEs) reported. Results: Compared to control group, CSMS, TNSS, TMS, VAS were significantly improved during the course of SLIT (p < 0.001). Besides, clinical improvement in nasal symptoms and reduction of medication use was also observed in SLIT group, compared to the baseline value (p < 0.001). Meanwhile, we observed that there was no significant difference between monosensitized group (n = 8) and polysensitized group (n = 29), as well as 12–13 weeks' preseasonal treatment group (n = 20) and 8–9 weeks' pre-seasonal treatment group (n = 17) belonging to the SLIT group in clinical efficacy (p > 0.05). No severe systemic AEs were reported. Conclusions: This study proved that A. annua-SLIT can provide equivalent efficacy and safety for SAR patients under the circumstance of accepting the pre-seasonal treatment of 8–9 or 12–13 weeks, regardless of monosensitization or polysensitization. [ABSTRACT FROM AUTHOR]

Introduction: Recent studies have shown that inflammatory patterns of nasal polyps from patients with chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) in East Asia have changed over time. However, to date there is a marked lack of similar data for CRSwNP in Northern China. This study thus aimed to assess the changes in the clinical and histological characteristics of CRSwNP patients from Northern China over the past 2–3 decades. Methods: This was a retrospective study, which examined data from 2 groups of 150 CRSwNP patients each, who had undergone endoscopic sinus surgery in Beijing Tongren Hospital from 1993 to 1995 (group A) and from 2015 to 2019 (group B). All relevant data for demographic, clinical, and histological parameters were collected for each patient from the 2 groups and compared for overall changes between the 2 groups. Results: The comorbidity of CRSwNP and asthma increased over time and the cellular phenotype of CRSwNPchanged significantly; in particular, the proportion of eosinophil-dominant CRSwNP increased, lymphocyte-dominant and plasma-dominant CRSwNP decreased significantly, and the proportions of neutrophil-dominant and mixed CRSwNP were not altered. The rate of polyp recurrence increased in CRSwNP but did not in eosinophilic CRSwNP. Smoking and age did not significantly impact the inflammatory patterns of CRSwNP. Conclusions: The inflammatory patterns of CRSwNP patients have changed and comorbidity of asthma significantly increased in CRSwNP patients in Northern China over the past 2–3 decades. [ABSTRACT FROM AUTHOR]

Background: A hallmark of eosinophilic chronic rhinosinusitis with nasal polyps (eCRSwNP) is mucosal eosinophil-predominant inflammation. Nasal nitric oxide (nNO) is a known biomarker of eosinophilic inflammation in the upper airway. However, the utility of nNO measurement in the upper airway remains controversial. The present study aimed to compare the use of other clinical parameters with nNO to prediagnose patients with eCRSwNP from Central China. Methods: From June 2019 to December 2019, 70 patients with CRSwNP undergoing endoscopic sinus surgery and 30 healthy subjects were enrolled. nNO measurements were performed in all of these subjects. Computed tomography scans, full blood count with differential analysis, and determination of total immunoglobulin E (total IgE) and plasma cytokines were performed before surgery. Receiver operating characteristic curves and logistic regression analysis were used to assess the predictive potential of the clinical parameters. Results: We recruited 24 patients with eCRSwNP and 46 with noneosinophilic CRSwNP (non-eCRSwNP). In patients with eCRSwNP, nNO levels were significantly higher than those in patients with non-eCRSwNP (p < 0.0001). Blood eosinophil percentages and counts, total IgE, and CT-derived ethmoid sinus and maxillary sinus ratio (E/M ratio) were all significantly higher compared with those in patients with non-eCRSwNP (p < 0.05). To diagnose eCRSwNP, the highest area under the curve (0.803) was determined for nNO. At a cutoff of >329 parts per billion (ppb), the sensitivity was 83.30% and the specificity was 71.70%. However, the levels of plasma cytokines Th1/Th2 were not significantly different between the histological types of CRSwNP (p > 0.05). Conclusion: Measurement of nNO is useful for the early diagnosis of eCRSwNP. [ABSTRACT FROM AUTHOR]

Background: Several foreign studies have shown long-term efficacy of sublingual immunotherapy (SLIT), but data on the long-term efficacy of SLIT in China are still lacking. Objective: We aimed to prospectively evaluate the long-term efficacy of a 2-year SLIT with Dermatophagoides farinae(D. farinae) drops in mono- and polysensitized children with allergic rhinitis (AR). Methods: Eighty house dust mite (HDM)-sensitized children (aged 4–11 years) with AR were enrolled in this prospective study. There were 40 children in both the monosensitized (to HDM only) and polysensitized groups. Both groups were treated with standardized SLIT (D. farinae drops) for 2 years, combined with pharmacotherapy according to their individual requirements, and were followed up for 7 years. A combined symptom and medication score (CSMS) was assessed and compared between the 2 groups during and after SLIT. Safety was evaluated based on adverse events (AEs). Results: There were 31 (77.5%) monosensitized and 29 (72.5%) polysensitized children who completed the study. After 2-year SLIT, the CSMS of 2 groups significantly decreased compared to baseline. The improvement persisted during the first 5 years at each visit, with a significant difference (all p < 0.01). In the monosensitized group, the CSMS significantly increased during the 6th and the 7th year compared to year 2 (both p < 0.05). Meanwhile, the polysensitized group showed a significant worsening of CSMS from the 5th to the 7th year (all p < 0.05). Furthermore, there was a statistical difference between the 2 groups in the 5th year of the study (p < 0.05). No severe AEs were reported. Conclusions: The study confirmed the long-term effects which lasted for 7 years after 2-year SLIT in mono- and polysensitized children. Compared with the polysensitized children, the monosensitized children noted a more sustained benefit. [ABSTRACT FROM AUTHOR]

Background: The implementation of allergen immunotherapy (AIT) requires extensive knowledge of allergen distribution in the region to identify high-risk regions for AIT utilization. However, the geographical distribution patterns of the major Dermatophagoides allergens in China remain unclear despite the increasing prevalence of these allergens. Methods: We performed comprehensive database searches of articles demonstrating the distribution patterns of Dermatophagoides-sensitized allergic rhinitis (AR) and allergic asthma (AA) in China, published between 1990 and 2017. Results: We retrieved 163 articles encompassing 114,302 allergen-positive cases to generate the distribution maps. The rate of sensitization to Dermatophagoidespteronyssinus(D. pteronyssinus)and Dermatophagoidesfarinae (D. farinae) was similar in patients with AR (75.1 vs. 75.2%, p > 0.05) but not in those with AA (78.5 vs. 77.7%, p = 0.041). Patients with AR and AA shared similar regional distribution patterns of both D. pteronyssinus and D. farinae sensitization, which were highest in the southern and central parts of China and lowest in the northern regions, especially in the Northwest. The overall rate of sensitization to D. pteronyssinus and D. farinae was significantly higher in patients with AA (p < 0.001). Additionally, the annual mean temperature and humidity were the 2 major determinants of D. pteronyssinus and D. farinae sensitization in AR and of D. pteronyssinus sensitization in AA, whereas the annual mean temperature was the sole determinant for D. farinae sensitization in AA. Conclusion: These findings may inform clinicians of the strategies for the prevention of Dermatophagoides sensitization and may be of benefit to the future clinical management of allergic diseasesassociated with sensitization to Dermatophagoides mites. [ABSTRACT FROM AUTHOR]

Background: Asthma is a common co-morbidity of allergic rhinitis (AR). The prevalence of these two allergic diseases has increased in China and has been shown to cluster in families independently. This study evaluated the association between maternal AR (presenting with or without asthma) and the allergic conditions in offspring. Methods: Women (n = 592) diagnosed with AR were recruited for this study; 379 patients presented with AR and 213 presented with both AR and asthma. Total serum IgE levels and nasal eosinophil counts were analyzed and correlated with disease presentation. Results: The prevalence of allergic conditions in offspring of mothers diagnosed with AR and asthma was significantly higher than the prevalence observed in children born to mothers presenting with AR only. Maternal total serum IgE and eosinophil counts were predictive of atopy in offspring. Children born to mothers presenting with persistent moderate-to-severe AR had the highest risk of developing atopic conditions (OR 6.26, 95% CI 3.26-12.02). Maternal age of 25-30 years at delivery was also associated with a higher risk for the allergic disease in offspring compared to maternal age of 36-40 (OR 2.13, 95% CI 1.31-3.47). Conclusions: The severity of maternal AR, asthma co-morbidity, elevated serum IgE levels and nasal eosinophilia were all associated with an increased risk of offspring developing allergic conditions. Children born to older mothers were protected against developing atopic disease. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Severe and widespread atopic dermatitis often fails to respond adequately to topical steroids and oral antihistamines and requires immunomodulatory drugs which, although effective, have undesirable toxic effects. Methods: In this prospective, randomized, double-blind, placebo-controlled trial, 71 patients with severe intractable atopic dermatitis were given an 8-week treatment with oral Xiao-Feng-San (XFS; 47 patients) or placebo (24 patients). Total lesion score, erythema score, surface damage score, pruritus score and sleep score were measured at 4-week intervals. Results: Fifty-six patients completed both the treatment and follow-up periods. The decrease in the total lesion score in the treatment group at 8 weeks was significantly greater than that of the placebo group (79.7 ± 5.8% vs. 13.5 ± 7.64%; p < 0.001). There was also a statistically significant difference between the treatment and placebo groups with regard to erythema, surface damage, pruritus and sleep scores. The difference between the 2 groups was still significant for all outcome measures except the erythema score at the 12-week follow-up, 4 weeks after the 8-week treatment had ended. Patients reported no side effects from treatment, although some commented on the unpalatability of the medication. Conclusion: Our study results suggest that the traditional Chinese herbal medicine XFS may be an alternative choice of therapy for severe, refractory, extensive and nonexudative atopic dermatitis. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Domestic endotoxin enhances airway inflammation and increases asthma severity in Caucasian children, but little data are published on indoor endotoxin exposure in Asian countries. This study investigated house dust endotoxin and Der p 1 levels in Hong Kong families with asthmatic children, and their effects on asthma severity. Methods: 115 asthmatics from a pediatric clinic underwent fractional exhaled nitric oxide (FeNO) and spirometric measurements. Home visits were then made within 2 weeks, during which parents completed the International Study of Asthma and Allergies in Childhood questionnaire. Settled dust was collected from patients’ mattresses, bedroom floors and living room floors. Endotoxin and Der p 1 were measured by limulus amebocyte lysate and immunoassay, respectively. Results: Endotoxin was detectable in all locations from all families, whereas Der p 1 was detectable in 58–70% of indoor sites. Floors of both bedroom and living rooms had higher endotoxin but lower Der p 1 levels than mattresses (p < 0.001 for both). Mattress endotoxin level correlated inversely with Der p 1 level (r = –0.308, p = 0.001). Household smoker, feather bedding and vacuum cleaning were independent determinants of indoor endotoxin. Timing of last bedding change was associated with Der p 1 levels at all sites. Mattress endotoxin level was associated with frequency of wheezing episodes (p = 0.044), but neither endotoxin nor Der p 1 was associated with FeNO and spirometric parameters. Conclusions: Domestic endotoxin levels are associated with frequency of wheezing episodes in asthmatic children but not their FeNO or spirometric measurements. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Asthma is a complex genetic disease, caused by the interaction of multiple genetic and environmental factors. T cell immunoglobulin domain and mucin domain (Tim) genes are located in chromosome 5q31–33, a region repeatedly linked to asthma or asthma-related phenotypes in several populations. Two members of Tim families, Tim-1 and Tim-3, which are expressed on T cell surface and potentially involved in T cell proliferation and differentiation, are good candidate genes for asthma. We investigated whether genetic variants or haplotypes in Tim-1 and Tim-3 genes confer susceptibility to asthma in a Chinese population. Methods: A total of 9 polymorphisms were selected by using the HapMap Han Chinese population data and a haplotype-tagging single nucleotide polymorphism approach. Polymerase chain reaction fragment length polymorphism was adapted to determine the genotype in 118 complete Chinese trios of asthma. Then, transmission disequilibrium test (TDT), haplotypic relative risk (HRR), linkage disequilibrium and haplotype analysis were performed. Results: The single locus TDT and HRR analysis showed the 9 polymorphisms were not transmitted preferentially to asthma-affected children (all p > 0.05). However, in both the haplotypic TDT and HRR analysis, the haplotype G-A-ins-C-G consisting of 5 Tim-1 polymorphisms was found to be overtransmitted to affected offspring (χ2 = 4.51, p = 0.03) and the haplotype G-G-G consisting of 3 Tim-3 polymorphisms was found to be undertransmitted to asthma children (χ2 = 8.24, p = 0.004). Conclusions: We conclude that it is unlikely that the Tim-1 or Tim-3 polymorphisms influence asthma susceptibility individually, but that the haplotypes of variants may be functional or may be in linkage disequilibrium with other functional single nucleotide polymorphisms. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Despite parallel increases in asthma and obesity prevalence, there is little data on obesity as a risk factor for atopy. The latter is an important phenotype in asthmatic patients. This study investigates the association between asthma traits, atopy and obesity-related markers in Chinese adolescents. Methods: 486 schoolchildren were recruited among participants of our population-based study on the epidemiology of obesity, and their allergy status was ascertained using a standardized questionnaire. Subjects’ anthropometry was recorded on-site, and fasting blood was collected for allergen-specific immunoglobulin E (IgE), lipids and systemic inflammatory biomarkers. Results: 98 (20.2%) subjects were classified as overweight or obese. Obesity status was not associated with asthma, allergic rhinitis or eczema (p > 0.25). Atopy was not associated with age-adjusted body mass index (BMI) or waist circumference. Atopy and presence of allergen-specific IgE did not differ between overweight or obese children and those with normal BMI (p > 0.25), although subgroup analysis suggested that cockroach sensitization was more common among males who were obese or overweight (p = 0.045). White cell count (WCC) was higher among atopic than nonatopic children (mean values 6.5 × 109/l vs. 6.2 × 109/l, p = 0.006). Logistic regression revealed WCC to be the only risk factor for atopy (OR 18.97, p = 0.004). Conclusions: Obesity is not associated with asthma or atopy in Chinese children. High WCC is an important risk factor for atopy in both males and females. Gender does not exert any consistent effect on the association between obesity and allergen sensitization in children. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Allergic rhinitis (AR) is a common disease and its prevalence is increasing worldwide. Data on the current prevalence of AR in China, one of the biggest countries in the world, with a population of around 1.3 billion citizens, are scarce. The aim of this study was to investigate the prevalence of self-reported AR in Chinese citizens. Methods: In a cross-sectional, population-based study, telephone interviews were conducted in 11 major cities in China after sampling target telephone numbers through the approach of random digital dialing. The questions for the telephone interviews were based on validated questionnaires. Results: A total of 38,203 telephone interviews were conducted from September 2004 to May 2005. The response rate was 63.7%. After adjustment for age and gender, the self-reported prevalence of AR was lowest in Beijing (8.7%) and highest in Urumqi (24.1%). Among the subjects with self-reported AR, 25.6% were diagnosed with persistent AR and 74.4% suffered from intermittent AR. Less than half of the subjects with self-reported AR had presented at a health clinic. In 37.3% AR had previously been diagnosed by physicians, and 33.1% of subjects with self-reported AR had been treated. Comorbidities reported were asthma (9.2%), rhinosinusitis (13.3%) and atopic dermatitis (16.4%). Conclusions: This study demonstrates that the self-reported prevalence of AR in 11 cities across Mainland China has wide variations, ranging from <10% to >20%; 26% of the self-reported AR subjects were classified as suffering from persistent AR. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background:Blomia tropicalis is an important domestic dust mite in the tropics and subtropics. This study describes cDNA cloning of the group 4 allergen of B. tropicalis, and the evaluation of the sensitization of this allergen in atopic populations from 2 geographic regions. Methods: cDNA cloning was carried out using the Smart RACE cDNA amplification kit. The full-length Blo t 4 cDNA was isolated by cDNA library screening, 5′ and 3′ rapid amplification of cDNA ends and long-distance PCR. Sequence analysis was performed with a combination of the Clustal W, CGC and Blast program packages. The cDNA was expressed in Pichia pastoris yeast. The skin prick test was used to evaluate the sensitization profile of recombinant Blo t 4, crude dust mite allergen extracts and major B. tropicalis recombinant allergen Blo t 5. Results: The cloned Blo t 4 had a molecular weight of 56 kDa and had 68% amino acid homology with group 4 allergens of Dermatophagoides pteronyssinus and 65% with those of Euroglyphus maynei. A sensitization profile to the expressed recombinant Blo t 4 allergen (28%) showed an unusually higher frequency than to the major allergen Blo t 5 (22%) in allergic subjects from Chengdu, PR China. In comparison, the subjects from Singapore showed very low sensitization to Blo t 4 (4%) compared with Blo t 5 (84%). Conclusions: Group 4 allergens of B. tropicalis may be an important dust mite allergen in certain distinct populations. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The prevalence of allergic sensitization has increased all over the world during last years and allergic sensitization may be related to genetic or environmental factors or to both. The objective of this study was to estimate the prevalence rates of allergic sensitization and assess the familial aggregation of allergic sensitization to aeroallergens in asthma index families. Methods: The skin prick test (SPT) reactivity to 8 aeroallergens and the SPT reactivity-related risk factors were evaluated. The allergic sensitization was based on SPT. Univariate and multivariate logistic regressive models were used to estimate the effect size (odds ratio, OR) of correlation within families with positive SPT. Results: Of 4,213 analyzed subjects in 1,006 asthma index families, 40.9% had at least one positive SPT, 42.3% in parents (father: 43.3%; mother: 42.3%), 43.9% in first offspring, and 36.0% in subsequent offspring. The most common allergens were Dermatophagoides pteronyssinus (DP), cockroach and Dermatophagoides farinae (DF). Allergic sensitization status of both parents and first offspring was related to the risk of allergic sensitization for subsequent offspring. The OR for the positive (father)-positive (first offspring) group was 1.92 (p < 0.01), 3.26 (p < 0.01) for the positive (mother)-positive (first offspring) group, and 2.12 (p < 0.01) for the positive (father)-positive (mother) group, which were adjusted for age, sex, body mass index, history of asthma and smoking status. Conclusions: Our findings supported a significant familial aggregation of allergic sensitization in this Chinese population and highlighted the role of genetic factors in allergic sensitization. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Susceptibility to the development of asthma and other atopic diseases is known to be associated with genetic components. However, association studies with interleukin-4 (IL-4), IL-4 receptor α subunit (IL-4Rα), tumor necrosis factor-α (TNF-α) and lymphotoxin-α (LT-α) genes were inconclusive, as both positive and negative results were obtained in several populations studied. We aimed to investigate the association of the polymorphisms for IL-4 (C–589T), IL-4Rα (Gln576Arg), TNF-α (G–308A) and LT-α (A252G) genes as candidates and asthma in adult Hong Kong Chinese population. Methods: The association study was conducted in an age- and smoking status-matched case-control design in asthma patients (n = 292) and healthy controls (n = 292) using polymerase chain reaction and restriction fragment length polymorphism. Results: No significant differences were found in allele and genotype frequencies of all four genes between patients and controls. After stratification by atopic status, the heterozygous AG genotype of LT-α (A252G) was found to increase risk of asthma in atopic population [odds ratio (OR) = 2.00, 95% CI 1.09–3.67, p = 0.024]. When stratified by smoking status, we found increased risk of asthma with subjects carrying the heterozygous AG and homozygous GG genotypes of LT-α in ever-smokers (OR = 2.73, 95% CI 1.11–6.69, p = 0.028 for heterozygotes; OR = 3.34, 95% CI 1.16–9.62, p = 0.026 for homozygotes). Conclusion: Our results suggest that the variability of LT-α genotypes may have potential implications for individual susceptibility to asthma in atopic or in ever-smoking Chinese adults in Hong Kong. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: The allergenic dust mite species Dermatophagoides pteronyssinus and Dermatophagoides farinae generally inhabit warm moist environments. This study tested the hypothesis that these allergenic species may thrive in air conditioner filters. Methods: A year-long investigation of the dust mite population densities and species identities living in air conditioner filters in Shenzhen City in Southern China was performed. Additional data describing the levels of major dust mite allergen proteins from samples collected in July and August 2004 were analyzed. Genetic polymorphism analysis of Der f 1 and Der f 2 genes in the collected animals was also conducted. Results: Our investigation revealed that larval dust mites started to grow in March, from which time their populations proceeded to steadily increase until reaching their population zenith in July and August. The dust mite populations decreased sharply in October and live dust mites were no longer observed in the winter. Among the mites collected in July and August, 30.1 and 25.8% were of the species D. farinae. The concentration of Der f 1 was 3.04 ± 1.75 and 3.21 ± 1.84 μg/g dust in July and August, respectively, and that of Der f 2 was 2.15 ± 0.82 and 2.04 ± 1.15 μg/g dust. Four types of Der f 1 and 5 types of Der f 2 cDNA sequences were cloned from collected Der f mites. Their sequences were highly homologous with those previously published in GenBank (No. AB034946.1 and No. AB195580.1). Conclusions: This research demonstrated that Der f allergens exist in the dust of air conditioner filters in this area. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]