Issue 3-The occupational burden of respiratory diseases, an update

INTRODUCTION AND AIMS

Workplace exposures are widely known to cause specific occupational diseases such as silicosis and asbestosis, but they also can contribute substantially to causation of common respiratory diseases. In 2019, the American Thoracic Society (ATS) and the European Respiratory Society (ERS) published a joint statement on the occupational burden of respiratory diseases. Our aim on this narrative review is to summarise the most recent evidence published after the ATS/ERS statement as well as to provide information on traditional occupational lung diseases that can be useful for clinicians and researchers.

RESULTS

Newer publications confirm the findings of the ATS/ERS statement on the role of workplace exposure in contributing to the aetiology of the respiratory diseases considered in this review (asthma, COPD, chronic bronchitis, idiopathic pulmonary fibrosis, hypersensitivity pneumonitis, infectious pneumonia). Except for COPD, chronic bronchitis and infectious pneumonia, the number of publications in the last 5 years for the other diseases is limited. For traditional occupational lung diseases such as silicosis and asbestosis, there are old as well as novel sources of exposure and their burden continues to be relevant, especially in developing countries.

CONCLUSIONS

Occupational exposure remains an important risk factor for airways and interstitial lung diseases, causing occupational lung diseases and contributing substantially in the aetiology of common respiratory diseases. This information is critical for public health professionals formulating effective preventive strategies but also for clinicians in patient care. Effective action requires shared knowledge among clinicians, researchers, public health professionals, and policy makers.

Influence of light at night on allergic diseases: a systematic review and meta-analysis

BACKGROUND

Allergic diseases impose a significant global disease burden, however, the influence of light at night exposure on these diseases in humans has not been comprehensively assessed. We aimed to summarize available evidence considering the association between light at night exposure and major allergic diseases through a systematic review and meta-analysis.

METHODS

We completed a search of six databases, two registries, and Google Scholar from inception until December 15, 2023, and included studies that investigated the influence of artificial light at night (ALAN, high vs. low exposure), chronotype (evening vs. morning chronotype), or shift work (night vs. day shift work) on allergic disease outcomes (asthma, allergic rhinitis, and skin allergies). We performed inverse-variance random-effects meta-analyses to examine the association between the exposures (ALAN exposure, chronotype, or shiftwork) and these allergic outcomes. Stratification analyses were conducted by exposure type, disease type, participant age, and geographical location along with sensitivity analyses to assess publication bias.

RESULTS

We included 12 publications in our review. We found that exposure to light at night was associated with higher odds of allergic diseases, with the strongest association observed for ALAN exposure (OR: 1.88; 95% CI: 1.04 to 3.39), followed by evening chronotype (OR: 1.35; 95% CI: 0.98 to 1.87) and exposure to night shift work (OR: 1.33; 95% CI: 1.06 to 1.67). When analyses were stratified by disease types, light at night exposure was significantly associated with asthma (OR: 1.62; 95% CI: 1.19 to 2.20), allergic rhinitis (OR: 1.89; 95% CI: 1.60 to 2.24), and skin allergies (OR: 1.11; 95% CI: 1.09 to 1.91). We also found that the association between light at night exposure and allergic diseases was more profound in youth (OR: 1.63; 95% CI: 1.07 to 2.48) than adults (OR: 1.30; 95% CI: 1.03 to 1.63). Additionally, we observed significant geographical variations in the association between light at night exposure and allergic diseases.

CONCLUSIONS

Light at night exposure was associated with a higher prevalence of allergic diseases, both in youth and adults. More long-term epidemiological and mechanistic research is required to understand the possible interactions between light at night and allergic diseases.

COVID-19 infodemic and health-related quality of life in patients with chronic respiratory diseases: A multicentre, observational study

Background

The explosion of information, misinformation and disinformation (the "infodemic") related to the coronavirus disease 2019 (COVID-19) pandemic on digital and social media is reported to affect mental health and quality of life. However, reports assessing the COVID-19 infodemic on health-related quality of life (HRQL) in patients with chronic diseases are scarce. In this study, we investigated the associations between the infodemic and HRQL in uninfected individuals with pre-existing chronic respiratory diseases (CRDs) such as asthma, chronic obstructive pulmonary disease (COPD) and other CRDs.

Methods

We conducted a multi-national, cross-sectional, observational study in Canada, India, New Zealand and the United Kingdom where we distributed a set of digitised questionnaires among 1018 participants with chronic respiratory diseases who were not infected with the SARS-CoV-2 virus at least three months prior to the study. We collected information about the infodemic such as news watching or social media use more than usual during the pandemic. HRQL was assessed using the short form of the chronic respiratory questionnaire (SF-CRQ). Demographic information, comorbidities, compliance, mental health, behavioural function, and social support were also recorded. We analysed the direct and indirect relationships between infodemic and HRQL using structural equation models (SEM).

Results

Of all participants, 54% were females and had a mean (standard deviation (SD)) age of 53 (17) years. We found that higher infodemic was associated with worse emotional function (regression coefficient β = -0.08; 95% confidence interval (CI) = -0.14 to -0.01), which means a one SD change of the higher infodemic latent variable was associated with a 0.08 SD change of emotional function level. The association between higher infodemic and worse emotional function was mediated by worse mental health and behavioural functions but is marginally ameliorated by improved social support. In stratification analysis, we found significant disease and country-wise variations in the associations between infodemic and SF-CRQ domain scores.

Conclusions

These results provide new evidence that the COVID-19 infodemic significantly influences the HRQL in patients with CRDs through a complex interplay between mental health, behavioural function, and social support. This new dimension of research also opens avenues for further research on infodemic-related health effects in other chronic diseases.

Polymorphism in ADAM33 gene associated with asthmatics in West Bengal, India - An investigation by in-silico analysis

Introduction

Asthma is one of the common chronic polygenic inflammatory diseases. Genome wide association studies have identified ADAM33 as an asthma candidate gene. The present study investigated possible association of rs2280090 (T1), rs2280091 (T2) and rs3918396 (S1) single nucleotide polymorphisms (SNPs) of ADAM33 with aeroallergen induced asthma in West Bengal population, India. In addition, in-silico analysis was performed to find out changes in protein function.

Methods

Forced expiratory volume in 1 second (FEV1)/Forced vital capacity (FVC), peak expiratory flow rate (PEFR) were assessed using spirometry in 1039 participants. Allergic sensitivity of 619 spirometry positive asthma patients was assessed by skin prick test (SPT) against 22 aeroallergens. For genotyping of T1, T2, and S1 SNPs in 540 allergic asthma patient and 420 control subjects, polymerase chain reaction-based restriction fragment length polymorphism was performed. Total Immunoglobulin-E (IgE) level was measured in both patients and controls. ADAM333 haplotype blocks were constructed using Haploview software v.4.2. Structural model of transmembrane and cytoplasmic domains of ADAM33 was generated using RaptorX. Protein-protein interaction was analysed using the STRING server.

Results

Highest number of patient sensitivity was observed towards Cocos nusifera (n = 215) and Dermatophagoides farinae (n = 229). Significant difference in sensitivity was observed between child and late adult (P = 0.03), child and early adult (P = 0.02), adolescent and late adult (P = 0.02) and adolescent and early adult (P = 0.01). Genotypic frequencies differed significantly between patients and controls (P < 0.05). rs2280090 GG, rs2280091GG and AG genotype, and rs3918396 AA carried significant risk for asthma (P = 0.02, P = 0.008, P = 0.04, P = 0.01 respectively). ADAM33 T1, T2, and S1 polymorphisms were in high Linkage Disequilibrium (D = 0.98). Haplotype consisting of rs2280090G, rs2280091G and rs3918396A alleles were found significantly higher in patient population in comparison with controls (OR = 2.03). IgE level differed significantly among different genotypes for T1, T2, and S1 SNPs analysed in pair (P < 0.0001). FEV1/FVC ratio differed significantly among different genotypes for T1, T2 and S1 SNPs analysed in pair (P < 0.0001). Significant difference of FEV1/FVC was also found between GGA and AAG haplotype (P < 0.0001). In-silico analysis revealed T1 and T2 polymorphisms are located in cytoplasmic domain of ADAM33 may cause bronchial smooth muscle cell mobility and cellular hyperplasia as well as cytoskeletal remodelling by altered interaction with different cytoplasmic proteins found by string analysis.

Conclusion

Present study showed significant association of T1, T2, and S1 polymorphisms of ADAM33 with aeroallergen-induced asthma in West Bengal, India. These polymorphisms may be used as prognostic markers and possible targets for therapeutics in future.

Less Social Deprivation Is Associated With Better Health-Related Quality of Life in Asthma and Is Mediated by Less Anxiety and Better Sleep Quality

BACKGROUND

Previous studies on health-related quality of life (HRQoL) in asthma have mainly focused on clinical and environmental determinants. Little is known about the role of social determinants on HRQoL in asthma.

OBJECTIVES

We aimed to investigate the association between social deprivation and HRQoL in asthma.

METHODS

A total of 691 adult asthmatics from Canada, India, New Zealand, and the United Kingdom were administered a digital questionnaire containing demographic information and questions about social and psychological attributes, sleep disturbances, and alcohol abuse. HRQoL was measured using the Short Form of the Chronic Respiratory Questionnaire (SF-CRQ). We analyzed the direct and indirect relationships between social deprivation and HRQoL using structural equation models with social deprivation as a latent variable. We tested for mediation via anxiety, depression, sleep disturbances, and alcohol abuse.

RESULTS

We found that less social deprivation (latent variable) was directly associated with better SF-CRQ domain scores such as dyspnea (regression coefficient β: 0.33; 95% confidence interval [CI]: 0.07 to 0.58), fatigue (β: 0.39; 95% CI: 0.14 to 0.64), and emotional function (β: 0.37; 95% CI: 0.11 to 0.62), but with the worse mastery score (β: -0.29; 95% CI: -0.55 to -0.03); however, those associations varied across participating countries. We also observed that among all individual social deprivation indicators, education, companionship, emotional support, instrumental support, and social isolation were directly associated with HRQoL, and the relationship between social deprivation and HRQoL was mediated through anxiety and sleep disturbances.

CONCLUSIONS

Our results demonstrated that less social deprivation was directly, and indirectly through less anxiety and better sleep quality, associated with better HRQoL in asthma.

Kinetics of Covid-19 antibodies in terms of titre and duration among healthcare workers: A longitudinal study

Background Most individuals with Covid-19 infection develop antibodies specific to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the dynamics of these antibodies is variable and not well-studied. We aimed to determine the titres of naturally acquired antibodies over a 12-week follow-up. Methods We recruited healthcare workers who had tested positive on a specific quantitative reverse transcription-polymerase chain reaction (qRT-PCR) for SARS-CoV-2, and then tested for the presence of immunoglobulin G (IgG) antibody against the same virus at baseline and again at 6 and 12 weeks. The antibody titre was determined by a semi-quantitative assay based on signal/cut-off ratio. Healthcare workers with antibody positivity were divided into those with high titre (ratio ≥12) and low titre (<12). Their demographic details and risk factors were surveyed through a Google form and analysed in relation to the antibody titres at three time-points. Results Of the 286 healthcare workers, 10.48% had high antibody titres. Healthcare workers who had tested positive by qRT-PCR and those who had received the Bacille Calmette-Guérin (BCG) vaccination or other immune-boosters had a higher frequency of high antibody titres. While there was a significant decline in antibody titres at 6 and 12 weeks, 87.46% of individuals positive for IgG antibody persisted to have the antibody even at 12 weeks. Conclusion Healthcare workers who tested positive for SARS-CoV-2 on qRT-PCR had a high positivity for the specific antibody, which continued to express in them even at 12 weeks. Further follow-up is likely to enhance our understanding of antibody kinetics following SARS-CoV-2 infection.

Effectiveness of budesonide formoterol fixed-dose combination MDI in reducing cough symptoms in COVID-19 patients: A real-world evidence study

Background

Cough is a wearisome and exasperating symptom affecting the daily life of the infected patient. Cough due to coronavirus disease 2019 (COVID-19) causes excessive morbidity in human populations globally. Apart from the morbidity associated with cough, it also enhances the transmission of this viral infection through droplets. Therefore, curbing cough is crucial to limit its spread. Patients often administer over-the-counter products and antitussive agents, which have no proven benefit. The present study was undertaken to find out if cough associated with COVID-19 and other indicative clinical outcomes is alleviated with a budesonide/formoterol fixed-dose combination (FDC) metered-dose inhaler (MDI).

Materials and Methods

A prospective observational study was conducted in mild COVID-19 patients who presented with a cough score ≥8 at presentation. Patients who were initiated on ICS-LABA MDI were observed as group A and those who were not initiated on MDI were observed as Group B. Cough symptom score (at baseline and on day 3 and day 7), the incidence of hospital admission and/or death, and need for mechanical ventilation were documented. Prescribing patterns of anti-cough medications were also noted and analysed.

Results

Compared to group B, a higher mean cough score reduction was noted for group A patients at day 3 and day 7 when compared to the baseline, and this was significant at P < 0.001. A significant negative correlation was also observed between mean latency of MDI initiation from the symptom onset and mean cough score reduction. Analysis of the proportion of patients prescribed medications to treat cough showed that overall, 10.78% did not require these, with a greater proportion in group A compared to group B.

Conclusion

Patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) COVID-19 who were treated with ICS-LABA MDI along with usual care benefitted significantly in terms of symptom reduction compared to usual care.

Allergic rhinitis in India

India is the home of nearly 20% of the global population with 1.35 billion people. Of all non-communicable diseases, allergic diseases such as allergic rhinitis (AR) and asthma appear to have increased in India over the past decades. Approximately 22% of adolescents currently suffer from AR in India. However, owing to the lack of adequate epidemiological studies in India, particularly in rural and suburban areas, this number may misrepresent the true burden of this disease. While the risk factors for AR are mainly environmental exposures or genetic factors, several new environmental, social, and behavioural risk factors such as the presence of dumpsters near residences, movement of vehicles near homes, and exposure to artificial light at night have been found to be associated with AR. However, despite international guidelines, the diagnosis and management of AR in India are often suboptimal, for multiple reasons such as the lack of specialized training in allergy and immunology among Indian clinicians, the lack of diagnostic facilities, and the high cost of medications. This review aims at highlighting the current scenario of AR in India and how it differs from the rest of the world. It also highlights the need for developing a strategic approach to enhance the quality of care for allergic diseases by upgrading education and training for healthcare professionals, creating awareness among clinicians and patients, and involving stakeholders and policymakers in making treatments accessible and affordable to patients.

Allergic diseases in India - Prevalence, risk factors and current challenges

Epidemiological studies have shown a rise in the prevalence of allergic diseases in India during the last two decades. However, recent evidence from the Global Asthma Network study has observed a decrease in allergic rhinitis, asthma and atopic dermatitis in children. Still, with a population over 1.3 billion, there is a huge burden of allergic rhinitis, asthma and atopic dermatitis, and this is compounded by an unmet demand for trained allergy specialists and poor health service framework. There is wide variation in the prevalence of allergic diseases between different geographical locations in India, and the reasons are unclear at present. This may at least in part be attributable to considerable heterogeneity in aero-biology, weather, air pollution levels, cultural and religious factors, diet, socioeconomic strata and literacy. At present, factors enhancing risks and those protecting from development of atopy and allergic diseases have not been well delineated, although there is some evidence for the influence of genetic factors alongside cultural and environmental variables such as diet, exposure to tobacco smoke and air pollution and residence in urban areas. This narrative review provides an overview of data from India regarding epidemiology, risk factors and genetics and highlights gaps in evidence as well as areas for future research.

A review on aero-allergen induced allergy in India

Allergic diseases such as bronchial asthma, rhinitis and eczema are an important public health issue globally in 21st century. Their prevalence and impact in India is high, in terms of total numbers of people affected. Due to diverse climate and lifestyle, the Indian population is exposed to a rich and varied range of aerobiological particles. In the last two decades in India, 83 pollens, 34 fungi, six dust mite and 19 insect species were reported as allergenic, often contributing to heavy allergenic exposure in indoor and outdoor environments. There are currently few practitioners who offer allergy diagnosis and treatment in India, but there is active basic and molecular research aiming to improve the health of allergic patients. This review explores the field of aero-allergy in India during the last two decades, with special emphasis on prevalence across various centres and relevant scientific advances such as genetic associations and new therapeutics. This review will be helpful for clinicians to select aero-allergens for sensitisation testing in patients suffering from symptoms in different regions of India, and to support patients undertaking prophylaxis of allergic symptoms in India according to local environmental conditions. This study also helps to define patient selection for allergy testing and the role of test results in guiding allergic disease management in the Indian context. Finally, we summarize genetic findings relevant to aero-allergy in India and discuss the development of novel therapeutics for investigation and management of aero-allergy in India.

Assessment of Co-Sensitization between Pollen and Food Allergen Sources among Bengali Population, West Bengal, India

INTRODUCTION

Secondary food allergies due to cross-reactivity between pollen and food allergens are a significant health burden in India. Prevalence of cross-reactivity varies by region, and particularly in West Bengal, it remains unexplored. The present study investigated sensitivities of pollen-related food allergy (PFA) patients of West Bengal by empirically determining co-sensitization patterns.

METHODS

The present study retrospectively analysed 1,310 pollen-allergic (PA) patients from the Allergy and Asthma Research Centre, West Bengal. A questionnaire survey was performed to record patients' demographic and clinical features and categorized into seasonal and perennial ones. All patients were subjected to the skin prick test and specific IgE for evaluation of sensitivity against 16 pollen and 16 food allergens. Co-relation and principal component analysis (PCA) was performed to determine co-sensitivity.

RESULTS

Seasonal allergic patients were comparatively higher than perennial ones. PFA patients were mostly sensitive to eggplant (n = 387), while Azadirachta indica (n = 341) was predominant sensitizer among pollen allergen sources. Cynodon dactylon showed maximum significant positive correlation with banana, orange, peanut, pineapple, cucumber, eggplant, potato, tomato, and wheat. In the seasonal group, Cynodon dactylon-specific IgE in PFA patients (median = 4.60 kU/L) was significantly higher from that of PA ones (median = 3.44 kU/L). Among 32 allergens tested, 27 were placed in first two dimensions of the PCA biplot.

CONCLUSION

The present study established that co-sensitivity between pollen and food allergen sources were predominant in allergic patients of West Bengal. The co-sensitization patterns among unrelated allergen sources may be due to possible expression of biologic cross-reactivity to similar allergens.

In silico analysis of single nucleotide polymorphism (rs34377097) of TBXA2R gene and pollen induced bronchial asthma susceptibility in West Bengal population, India

Introduction

Prevalence of asthma is increasing steadily among general population in developing countries over past two decades. One of the causative agents of broncho-constriction in asthma is thromboxane A2 receptor (TBXA2R). However few studies of TBXA2R polymorphism were performed so far. The present study aimed to assess potential association of TBXA2R rs34377097 polymorphism causing missense substitution of Arginine to Leucine (R60L) among 482 patients diagnosed with pollen-induced asthma and 122 control participants from West Bengal, India. Also we performed in-silico analysis of mutated TBXA2R protein (R60L) using homology modeling.

Methods

Clinical parameters like Forced expiratory volume in 1 second (FEV₁), FEV₁/Forced vital capacity (FVC) and Peak expiratory flow rate (PEFR) were assessed using spirometry. Patients' sensitivity was measured by skin prick test (SPT) against 16 pollen allergens. Polymerase chain reaction-based Restriction fragment length polymorphism was done for genotyping. Structural model of wild type and homology model of polymorphic TBXA2R was generated using AlphaFold2 and MODELLER respectively. Electrostatic surface potential was calculated using APBS plugin in PyMol.

Results

Genotype frequencies differed significantly between the study groups (P=0.03). There was no significant deviation from Hardy-Weinberg equilibrium in control population (χ2=1.56). Asthmatic patients have significantly higher frequency of rs34377097TT genotype than control subjects (P=0.03). SPT of patients showed maximum sensitivity in A. indica (87.68%) followed by C. nusifera (83.29%) and C. pulcherima (74.94%). Significant difference existed for pollen sensitivity in adolescent and young adult (P=0.01) and between young and old adult (P=0.0003). Significant negative correlation was found between FEV1/FVC ratio and intensity of SPT reactions (P<0.0001). Significant association of FEV₁, FEV₁/FVC and PEFR was observed with pollen-induced asthma. Furthermore, risk allele T was found to be clinically correlated with lower FEV₁/FVC ratio (P=0.015) in patients. Our data showed R60L polymorphism, which was conserved across mammals, significantly reduced positive electrostatic charge of polymorphic protein in cytoplasmic domain thus altered downstream pathway and induced asthma response.

Discussion

The present in-silico study is the first one to report association of TBXA2R rs34377097 polymorphism in an Indian population. It may be used as prognostic marker of clinical response to asthma in West Bengal and possible target of therapeutics in future.

Association of Interleukin 6 and Interleukin 8 genes polymorphisms with house dust mite-induced nasal-bronchial allergy in a sample of Indian patients

Background

Genetic background of nasal-bronchial allergy (NBA) is well documented. House Dust Mites (HDMs) are reported to elicit NBA symptoms. Susceptibility to HDM sensitization varies considerably from person to person. Interleukin 6 (IL 6) and Interleukin 8 (IL 8) are studied previously for genetic association with several diseases. To the best of our knowledge, the genetic association of HDM-induced NBA has not been largely reported from India. The aim of our present study was to evaluate any possible association of IL 6 and IL 8 gene polymorphisms with HDM-induced NBA in an Indian population.

Methods

IL 6 (− 572G/C, − 597G/A) and IL 8 polymorphisms (− 251A/T, + 781C/T) were analyzed in a HDM-sensitized group (N = 372) and a control group (N = 110). Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR–RFLP) based genotyping was done. Chi-square test and Fisher’s exact tests were applied for statistical analysis.

Results

IL 6 − 597G/A and IL 8 + 781C/T were not associated with HDM-sensitization, while IL 6 − 72G/C and IL 8 − 51A/T showed significant associations in terms of both genotype and allele frequencies. For both the SNPs, minor allele frequencies were significantly higher in the patients compared to the control. Moreover, IL 6 -572G/C and IL 8 -251A/T were found to be strongly linked with HDM sensitization and severity.

Conclusion

This is probably the pioneer study to describe the association of IL 6 and IL 8 polymorphisms with HDM sensitization in any Indian population. The results suggested that IL 6 -572G/C and IL 8 -251A/T may exert a risk of HDM sensitization leading to NBA.

COVID ‐19 vaccine‐associated myositis – a case report

Myositis is one of the uncommon adverse events following COVID‐19 vaccination, and its mechanism is still unclear. A strong clinical suspicion and further evaluation are important not only for early diagnosis and management but also for better understanding of the unprecedented effects of this novel vaccine. We present a case of myositis following the first dose of the ChAdOx1 nCoV‐19 Corona Virus Vaccine, evidenced by serology and MRI.

The Influence of Artificial Light at Night on Asthma and Allergy, Mental Health, and Cancer Outcomes: A Systematic Scoping Review Protocol

Artificial light at night (ALAN) exposure is associated with the disruption of human circadian processes. Through numerous pathophysiological mechanisms such as melatonin dysregulation, it is hypothesised that ALAN exposure is involved in asthma and allergy, mental illness, and cancer outcomes. There are numerous existing studies considering these relationships; however, a critical appraisal of available evidence on health outcomes has not been completed. Due to the prevalence of ALAN exposure and these outcomes in society, it is critical that current evidence of their association is understood. Therefore, this systematic scoping review will aim to assess the association between ALAN exposure and asthma and allergy, mental health, and cancer outcomes. This systematic scoping review will be conducted in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses statement. We will search bibliographic databases, registries, and references. We will include studies that have described potential sources of ALAN exposure (such as shift work or indoor and outdoor exposure to artificial light); have demonstrated associations with either allergic conditions (including asthma), mental health, or cancer-related outcomes; and are published in English in peer-reviewed journals. We will conduct a comprehensive literature search, title and abstract screening, full-text review, and data collection and analysis for each outcome separately.

Association of HLA-DQ and IL13 gene variants with challenge-proven shrimp allergy in West Bengal, India

Little is known about genetic factors and mechanisms underlying shrimp allergy. Genome-wide association studies identified HLA class-II and IL13 genes as highly plausible candidates for shrimp allergy. The present study was designed to investigate potential associations of HLA-DQ rs9275596, IL13 rs20541, and IL13 rs1800925 polymorphisms with challenge-proven shrimp allergy using the data from 532 people of West Bengal, India; selected on basis of positive skin prick test, elevated specific IgE and medical history. Risk genotypes, i.e., HLA-DQ rs9275596 CC, IL13 rs20541 AA, and IL13 rs1800925 TT, were found to be significantly associated with challenge positive shrimp allergy (P = 0.04, 0.01, and 0.03, respectively). Distribution of genotypes for HLA-DQ and IL13 polymorphisms in allergic and control subjects showed significant difference between younger (20-40 years) and older (> 40 years) age group (P = 0.006). Risk genotypes significantly associated with elevated shrimp-specific IgE. IL13 TA haplotype significantly associated with shrimp allergy and elevated specific IgE (P = 0.02). Synergistic effect of IL13 TA haplotype-HLA-DQ rs9275596 CC genotype interaction significantly elevated specific IgE (P = 0.03). The present study suggests that HLA-DQ and IL13 polymorphisms pose major risk for shrimp allergic patients in West Bengal, India and thus could be helpful for early target-specific therapeutic intervention in near future.

Pediatric allergic diseases in the Indian subcontinent-Epidemiology, risk factors and current challenges

INTRODUCTION

India is low-middle-income country (LMIC) with a population of 1.3bn, comprising about 20% of the global population. While the high-income Western countries faced an "allergy epidemic" during the last three decades, there has been a gradual rise in prevalence of allergic diseases in India.

METHODS

Narrative review.

RESULTS AND DISCUSSION

Allergic diseases occur as a consequence of a complex interplay between genetic and environmental factors. There are multiple contrasting determinants that are important to consider in India including high levels of air pollution, in particular PM_2.5 due to burning of fossil fuels and biomass fuels, diverse aero-biology, tropical climate, cultural and social diversity, religious beliefs/myths, linguistic diversity, literacy level, breastfeeding and weaning, diet (large proportion vegetarian), and high incidence rates of TB, HIV, malaria, filariasis, parasitic infestations, and others, that not only shape the immune system early in life, but also impact on biomarkers relevant to allergic diseases. India has a relatively weak and heterogeneous healthcare framework, and allergology has not yet been recognized as an independent specialty. There are very few post-graduate training programs, and allergic diseases are managed by primary care physicians, organ-based specialists, and general pediatricians. Adrenaline auto-injectors are not available, there is patient unaffordability for inhalers, nasal sprays, and biologics, and this is compounded by poor compliance leading to 40%-50% of asthmatic children having uncontrolled disease and high rates of oral corticosteroid use. Standardized allergen extracts are not available for skin tests and desensitization. This article provides a critical analysis of pediatric allergic diseases in India.

Risk Benefit Analysis in Reference to use of LMWH in COVID-19

Venous thromboembolism (VTE) and disseminated intravascular coagulation (DIC) are frequent cardiovascular and/or respiratory complications among hospitalized patients of COVID-19 infection. A relatively high mortality of severe coronavirus disease 2019 (COVID-19) is worrying, and the application of heparin in COVID-19 has been assessed and recommended with some expert consensus because of the risk of DIC and venous thromboembolism. However, "Risk Benefit Analysis" on the aspect of safety in using low molecular weight heparin (LMWH) in COVID-19 patients for thrombosis prophylaxis has been explained below with a few case studies and detailed information from various clinical evidence. COVID-19 infection has been associated with inflammation and a prothrombotic state, with increase in fibrin, fibrin degradation products, fibrinogen, and D-dimers. Heparin treatment including unfractionated and low molecular weight heparin appears to be associated with better prognosis in severe COVID-19 patients with coagulopathy. Major studies since the onset of this pandemic, found better prognosis in severe COVID-19 patients meeting SIC criteria or with markedly elevated D-dimer, by approaching thrombosis prophylaxis with LMWH.

An appraisal of allergic disorders in India and an urgent call for action

India is the second most populous country in the world with a population of nearly 1.3 billion, comprising 20% of the global population. There are an estimated 37.5 million cases of asthma in India, and recent studies have reported a rise in prevalence of allergic rhinitis and asthma. Overall, 40-50% of paediatric asthma cases in India are uncontrolled or severe. Treatment of allergic rhinitis and asthma is sub-optimal in a significant proportion of cases due to multiple factors relating to unaffordability to buy medications, low national gross domestic product, religious beliefs, myths and stigma regarding chronic ailment, illiteracy, lack of allergy specialists, and lack of access to allergen-specific immunotherapy for allergic rhinitis and biologics for severe asthma. High quality allergen extracts for skin tests and adrenaline auto-injectors are currently not available in India. Higher postgraduate specialist training programmes in Allergy and Immunology are also not available. Another major challenge for the vast majority of the Indian population is an unacceptably high level of exposure to particulate matter (PM)_2.5 generated from traffic pollution and use of fossil fuel and biomass fuel and burning of incense sticks and mosquito coils. This review provides an overview of the burden of allergic disorders in India. It appraises current evidence and justifies an urgent need for a strategic multipronged approach to enhance quality of care for allergic disorders. This may include creating an infrastructure for education and training of healthcare professionals and patients and involving regulatory authorities for making essential treatments accessible at subsidised prices. It calls for research into better phenotypic characterisation of allergic disorders, as evidence generated from high income western countries are not directly applicable to India, due to important confounders such as ethnicity, air pollution, high rates of parasitic infestation, and other infections.

Individual circadian preference (chronotype) is associated with asthma and allergic symptoms among adolescents

Circadian rhythm is an endogenously driven cyclical process that regulates most of our bodily functions, such as sleep–wakefulness cycle, metabolism, and a wide range of cellular, molecular and behavioural processes. Chronotype, or an individual's preferred time of sleep and activity, is one of the major internal cues that helps to harmonise one's biological events according to its circadian timing [1]. Three major variations of chronotype exist among humans, those who prefer to wake up early and sleep early at night (known as morning types or “larks”), those who prefer late sleep at night and late waking up in the morning (referred to as evening type or “owls”) and those who remain in between (intermediate type) [1].

Individual preference of sleep and activity (chronotype) might play an important role on asthma and allergic diseases in adolescents: this link underscores a potential plausible behavioural intervention for asthma and allergic diseases in young populationhttps://bit.ly/2THta9I

Regulation of key molecules of immunological synapse by T11TS immunotherapy abrogates Cryptococcus neoformans infection in rats

Cryptococcus neoformans infects and disseminates in hosts with diminished T cell responses. The immunomodulator T11TS (T11 target structure) had profound potential in glioma as well as C. neoformans infected model for disease amelioration. It is been established by our group that T11TS potentiates Calcineurin-NFAT pathway in T cells of C. neoformans infected rats. We investigated the upstream Immunological Synapse (IS) molecules that are vital for the foundation of initial signals for downstream signaling, differentiation and proliferation in T cells. Improved RANTES level in the T11TS treated groups suggests potential recruitment of T cells. Down-regulation of TCRαβ, CD3ζ, CD2, CD45 and CD28 molecules by cryptococcus were boosted after T11TS therapy. Heightened expression of inhibitory molecule CTLA-4 in cryptococcosis was dampened by T11TS. The decline of MHC I, MHC II and CD80 expression on macrophages by C. neoformans were enhanced by T11TS. The dampening of positive regulators and upsurge of negative regulators of the IS during cryptococcosis was reversed with T11TS therapy resulting in enhanced clearance of fungus from the lungs as envisaged by our histological studies. This preclinical study with T11TS opens a new prospect for potential immunotherapeutic intervention against the devastating C. neoformans infection with positive aspect for the long-term solution and a safer immunotherapeutic regimen.

T11TS immunotherapy potentiates the repressed calcineurin-NFAT signalling pathway of T cells in Cryptococcus neoformans infected rats: a cue towards T-cell activation for antifungal immunity

AIMS

To examine the modulation of the interacting partners of the calcineurin (CaN)-NFAT pathway in T cells during Cryptococcus neoformans fungal infection and post-T11TS immunotherapy.

METHODS AND RESULTS

Wistar rats were infected with C. neoformans and followed by immunotherapy with immune-potentiator T11TS. T cells were analysed by flow cytometry, immunoblotting and nuclear translocation study. The signalling proteins LCK, FYN, LAT, PLCγ1 and CaN in T cells were regulated by C. neoformans infection resulting in reduced nuclear translocation of NFAT and IL-2 expression. Following T11TS immunotherapy, the expressions of the above-mentioned proteins were boosted and thus resulting in the clearance of C. neoformans from lung and spleen.

CONCLUSIONS

The precise mechanism of suppression of the T-cell function by C. neoformans is still unknown. Previously, we have shown that T11TS positively regulates the function of T cells to abrogate glioma and other immunosuppressive conditions. T11TS immunotherapy increased the expression of the above signalling partners of the CaN-NFAT pathway in T cells and improved nuclear retention of NFAT. As a result, an increased IL-2 expression leads to activation and proliferation of T cells.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results demonstrate the role of T11TS in restoring the CaN-NFAT signalling pathway in T cells. It identifies T11TS as an immunotherapeutic agent with potential clinical outcomes to counteract C. neoformans infection.

Assessment of Hymenoptera and Non-Hymenoptera Insect Bite and Sting Allergy Among Patients of Tropical Region of West Bengal, India

West Bengal, India, is inhabited by abundance and variety of insects that triggers sensitization in some humans to inhalant allergens and/or insect stings/venoms. Lack of research on this topic prevented accurate diagnosis and proper follow-up treatments to patients suffering from insect-induced allergies. The aim of our study was to identify the allergy-causing insects and evaluate resulting sensitization among a study population in West Bengal, India. The skin prick test (SPT) evaluated sensitivity of 450 patients who sought treatment at the Allergy and Asthma Research Center from July 2017 to June 2018. Eight insect allergens were tested: Common Black Ant (Lasius niger, Linnaeus 1758), Fire Ant (Solenopsis invicta, Buren 1972), Honey Bee (Apis cerana indica, Fabricius 1798), Common Wasp (Vespula vulgaris, Linnaeus 1758), Mosquito (Aedes aegypti, Linnaeus in Hasselquist 1762), American Cockroach (Periplaneta americana, Linnaeus 1758), House Fly (Musca domestica, Linnaeus 1758), and Grasshopper (Gesonula punctifrons, Stal 1861). From a total of 450 patients evaluated, 370 patients had positive SPT reaction from at least one of the 8 insect allergens tested. Sensitivity to some Hymenoptera insects (common black ant, 87.62%; fire ant, 84.59%; and honey bee, 67.02%) was found in higher proportion than non-Hymenoptera group (mosquito, 66.67%; American cockroach, 33.33%; house fly, 10.41%; and grasshopper, 5.14%). There was significant difference in sensitivity among child, adolescent, and adult (P < 0.001). While female patients showed more sensitivity than males to SPT, the difference was statistically insignificant. In regards to occupation, farmers and bee keepers were most sensitive of field workers sensitive to Hymenoptera-derived allergens.

Association of the STAT6 rs3024974 (C/T) Polymorphism with IgE-Mediated Food Sensitization among West Bengal Population in India

INTRODUCTION

Genetic polymorphisms associated with IgE-mediated food sensitization have been a robust area of research for decades. A genome-wide search for susceptible loci regulating the IgE response (atopy) identified the candidate gene STAT6, which is important in the context of food allergic manifestations.

OBJECTIVE

The present study was designed to investigate the sensitization of West Bengal population against some common allergenic food items and to study the role of the STAT6 gene polymorphism in elevating food-specific IgE levels among sensitized individuals.

METHODS

Skin prick test was performed for 6 food items among 501 patients (126 children, 85 adolescents, and 290 adults)from West Bengal, India. Among them, 165 patients were selected for measurement of total IgE and food-specific IgE levels along with 165 controls. Finally, the STAT6 (rs3024974 (C/T) polymorphism was genotyped in 139 cases and control subjects.

RESULTS

Shrimp was identified as a dominant food allergen in adolescents and adults, whereas milk sensitization was highest in children. Food-sensitized patients with onset during childhood had significantly higher total IgE levels compared to patients with onset during adulthood (p < 0.00001). The frequency of the rs3024974 CC genotype in both cases and control subjects (55.40 and 46.76%, respectively) was higher than that of CT or TT. Patients with childhood onset bearing the CC genotype had significantly higher specific IgE levels in comparison to those with adult onset (p = 0.001).

CONCLUSION

Food sensitization has a genetic background and the rs3024974 polymorphism is associated with susceptibility and reaction severity in food-sensitized patients in West Bengal population in India.

Investigation of house dust mite induced allergy using logistic regression in West Bengal, India

BACKGROUND

The diagnosis of house dust mite (HDM) allergy based on Skin prick test (SPT) is not accurate, especially in lower risk cases. Our aim is to develop and validate a predictive model to diagnose the HDM allergic symptoms (urticaria, allergic rhinitis, asthma).

METHODS

A forward-step logistic regression model was developed using a data set of 537 patients of West Bengal, India consisting of clinical variables (SPT based on 6 allergens of house dust and house dust mites, total IgE) and demographic characteristics (age, sex, house conditions). The output probability was estimated from the allergic symptoms shown by the patients. We finally prospectively validated a data set of 600 patients.

RESULTS

The gradual inclusion of the variables increased the correlation between observed and predicted probabilities (correlation coefficient (r2) = 0.97). The model development using group-1 showed an accuracy rate of 99%, sensitivity and specificity of 99.7% and 88.6% respectively and the area under the receiver operating characteristics (ROC) curve (AUC) of 99%. The corresponding numbers for the validation of our model with group-2 were 87%, 95.6% and 66% and 86% respectively. The model predicted the probability of symptoms better than SPTs in combination (accuracy rate 0.76-0.80), especially in lower risk cases (probability< 0.8) that are highly difficult to diagnose.

CONCLUSION

This is perhaps the first attempt to model the outcome of HDM allergy in terms of symptoms, which could open up an alternative but highly efficient way for accurate diagnosis of HDM allergy enhancing the efficiency of immunotherapy.

Evaluation of Sensitivity Toward Storage Mites and House Dust Mites Among Nasobronchial Allergic Patients of Kolkata, India

House dust mites (HDMs) are the major constituents of house dust (HD). HD and HDM sensitization is well documented worldwide. Storage mite (SM) sensitization is presently lacking from India. The present study evaluated the sensitization of both HDM and SM among 372 allergic rhinitis patients reported to the Allergy and Asthma Research Center of Kolkata metropolitan, India. HD samples were collected from the patients' home and analyzed for the major constituent mites. HD and six constituent mites Dermatophagoides pteronyssinus (DP), Dermatophagoides farina Hughes (Acari: Pyroglyphidae) (DF), Blomia tropicalis (BT), Acarus siro Linnaeus (Acari: Acaridae) (AS), Lepidoglyphus destructor (LD), and Tyrophagus putrescentiae (Schrank) (Acari: Acaridae) (TP) are tested for the allergenic potential through Skin Prick Test (SPT). Three SMs, namely AS, LD, and TP, were newly included in the mite SPT extract for the first time in Kolkata. In total, 330 patients showed significant positive SPT toward any one allergen tested. HD was the major elicitor exhibiting 92.42% response. Individuals of age group 15-40 were the worst sufferers. DF showed the highest sensitization (87.87%) among the dust mites. The SMs also contributed significantly to prove their sensitizing potential. SPT rates for AS, LD, and TP were 33, 25, and 18%, respectively. SPT grades and total Immunoglobulin E (IgE) were positively correlated for each of the allergens. Most of the patients were multi-sensitized (95%) and represented markedly high total IgE levels (>500 IU/ml). Three SMs proved to be significant allergens for the studied population. The sensitization toward these SMs is first time reported from India and can be recommended for inclusion of routine SPT for better outcome in the future.

T11TS immunotherapy augments microglial and lymphocyte protective immune responses against Cryptococcus neoformans in the brain

Cryptococcus neoformans, the encapsulated yeast acquired through inhalation, remains localized in lungs, but harbours the CNS in immunocompromised individuals. Several treatment regimes have failed combating this disease totally, but long-term usage of drugs leads to organ damage. As T11-target structure (T11TS) has documented profound immune potentiation, we aimed to investigate the role of microglia, pivotal immune cells of brain in ameliorating cryptococcosis, with T11TS immunotherapy. Murine model with C neoformans infection was prepared by intraperitoneal injection and the brains of rats examined 7 days post-infections for histopathology by PAS and Alcian blue staining corroborated with organ fungal burden evidencing restorative T11TS action on Cryptococcal meningitis. Immunotherapy with three doses of T11TS, a CD2 ligand, in C neoformans infected rats, upregulates toll-like receptors 2, -4 and -9 of microglia, indicating increased phagocytosis of the fungus. Flowcytometric analysis revealed increased numbers of T11TS treated brain infiltrating CD4⁺ and CD8⁺ T-lymphocytes along with increased MHC I and MHC II on microglia, activating the infiltrating lymphocytes aiding the killing mechanism. Present study also indicated that T11TS increased production of Th1 inflammatory cytokines conducive to fungal elimination while the inhibitory Th2 cytokines were dampened. This preclinical study is first of its kind to show that T11TS effected profound immune stimulation of microglial activity of C neoformans infected rats eradicating residual fungal burden from the brain and can be a useful therapeutic strategy in fighting against this deadly disease.

Unravelling the apoptotic mechanisms in T-lymphocytes in an animal model for pollen induced airway allergy and studying the impact of specific immunotherapy

Asthma is a chronic inflammatory disorder of the airways, increasing in prevalence worldwide. Reduced T cell apoptosis may interfere with the down-regulation of an immune response resulting in T cell accumulation contributing to the chronic inflammation of asthma. Most studies focused so far on apoptosis of eosinophils but the detailed role of T lymphocytes apoptosis in allergic diseases is unclear yet. The present experimental study was designed to discern the modulation of various apoptotic proteins of splenic T lymphocytes in a previously established rat model of Alstonia scholaris pollen induced airway allergy. Flowcytometry, immunoblotting, and immunofluorescence imaging techniques were employed for the present investigation. Annexin-V studies registered early apoptotic rate of lymphocytes with allergen sensitization and challenge which was corrected following mucosal immunotherapy. The study demonstrates that allergen sensitization and challenge reduced apoptosis of splenic T-lymphocytes via Fas mediated extrinsic pathway, Bax/Bcl2 regulated intrinsic pathway and also perforin/granzyme mediated pathway which were normalized following allergen specific intranasal immunotherapy. Inadequate T cell apoptosis in asthma appears to interfere with normal T cell elimination, resulting in T cell accumulation, which contributes to chronic inflammation and may be the major underlying cause for tissue damage which can be modulated by intranasal immunotherapy. Thus the apoptosis inducing effect of allergen immunotherapy necessitates more studies to elaborate on its effects on various effector cells of airway inflammation.

Exposure to heavy metals alters the surface topology of alveolar macrophages and induces respiratory dysfunction among Indian metal arc-welders

BACKGROUND

Despite the available clinico-epidemiological evidence of heavy metal-associated respiratory health hazards among metal arc-welders, experimental confirmation of such an association is lacking.

METHODS

In this study, we recruited 15 metal arc-welders and 10 referent workers without direct exposure. We assessed respiratory health through a questionnaire and spirometry; estimated manganese, nickel and cadmium levels in blood, urine and induced sputum; performed differential counts of sputum leucocytes and measured plasma malondialdehyde (MDA). We used atomic force and scanning electron microscopy to assess the physical property of the alveolar macrophages (AMs) obtained from induced sputum and analysed cell surface deposition of heavy metals using energy dispersion X-ray analysis (EDX). Sputum cellular DNA damage was assessed by DNA-laddering assay.

RESULTS

There was a higher body burden of manganese and nickel in the metal arc-welders than the referents. Among major spirometric indices, only the forced mid-expiratory flow rates (FEF_25-75) were reduced in the welders compared with the referents (63.4 ± 14.7 vs. 89.2 ± 26.7, p < 0.01); this reduction was associated with both heavy metal levels (β: -41.8, 95% CI: -78.5% to -5.1%) and plasma MDA (-0.37; -0.68 to -0.06). In metal arc-welders, significant physical and morphological changes were observed in AMs through microscopic evaluation while EDX analyses demonstrated higher deposition of heavy metals on the AM cell surface than the referents. We also observed a higher degree of DNA damage in the sputum cells of the exposed workers than the referents.

CONCLUSION

Heavy metal exposure-induced adverse respiratory effects among metal arc-welders are mediated through haematological and cytological interactions.

Sensitization to Common Aeroallergens in the Atopic Population of West Bengal, India: An Investigation by Skin Prick Test

BACKGROUND

Aeroallergen sensitization is increasing worldwide. The optimal management of allergic disease requires the identification of the allergic sensitivities of the patient. Complete data of offending aeroallergens are scant from West Bengal, India. Hence, we employed a retrospective analysis of an atopic population of West Bengal to investigate the rate of sensitivity toward common aeroallergens including pollens, molds and house dust mites.

OBJECTIVES

The aim of the present study was to evaluate the profile of skin prick test (SPT) reactivity of an atopic population of eastern India.

METHODS

The prevalence aeroallergen sensitization was investigated by SPT along with a questionnaire survey of patients who visited the Allergy and Asthma Research Center of West Bengal, India, from June 2016 to May 2018. Patients were categorized according to the demographic (age, gender) and clinical aspects. Statistical tests were applied to differentiate between age and gender of the sufferers.

RESULTS

524 out of 605 patients exhibited a positive SPT response toward one or more aeroallergens tested. One-way ANOVA following Tukey's post hoc test reveals the age group of 15-40 years was more sensitized than that of < 15 years and no male-female discrimination was found using the paired t test. House dust mites, namely Dermatophagoides pteronyssinus and Dermatophagoides farinae, elicited most significant SPT results (80.34 and 84.92%, respectively) followed by Cocos (73.28%) and Azaridacta (57.25%) pollen. The most sensitive mold was Alternaria alternata (26.9%). Allergic rhinitis, bronchial asthma and atopic dermatitis were recorded as the common symptoms. Other influencing factors were family history, nature and season/time of onset and house conditions.

CONCLUSION

Following the increasing trend, house dust mite sensitization still held the dominance like in any other Indian population reported earlier. This study would pave the way to construct a standard and minimal SPT panel for the atopic patients of eastern India.

Prevalence and Risk Factors of Asthma and Allergy-Related Diseases among Adolescents (PERFORMANCE) study: rationale and methods

Despite a considerable number of international reports on allergic diseases among children, information about the prevalence and risk factors of asthma and allergy-related diseases among Indian adolescents is relatively sparse. The Prevalence and Risk Factors of Asthma and Allergy-Related Diseases among Adolescents (PERFORMANCE) study has been conceived to study the aetiology of asthma and allergic diseases including rhinoconjunctivitis, atopic eczema and food allergies among adolescents in West Bengal, India, using standardised methods and collaborations. The aims of the study are: 1) to estimate the prevalence and risk factors of asthma and allergic diseases among the adolescents residing in rural, suburban and urban areas of West Bengal; 2) to obtain information about the possible role of lifestyle factors (smoking, diet and physical activity) on the disease prevalence; and 3) to create a network for further investigation on social, environmental and genetic factors affecting the diseases. The PERFORMANCE study comprises two phases. The phase I study will investigate the prevalence and possible contributing factors of asthma and allergic diseases in a defined population. The phase II study will be performed as a follow-up of phase I to assess the incidence of asthma and allergic diseases.

The PERFORMANCE study: investigating the prevalence and risk factors of allergy and asthma among Indian adolescentshttp://ow.ly/jP2v30kmt8u

Allergen immunotherapy modulates sensitivity of Treg cells to apoptosis in a rat model of allergic asthma

AIM

To study the apoptosis of Foxp3⁺ Treg cells following Alstonia scholaris pollen sensitization-challenge and following allergen immunotherapy.

MATERIALS & METHODS

Wistar rats were sensitized-challenged with Alstonia scholaris pollen and were further given intranasal immunotherapy. For the analysis of the apoptotic proteins on Treg cells by flow cytometry, multiple gating procedures were followed.

RESULTS

Allergen sensitization-challenge increases Annexin-V, Fas, FasL, caspases-8, 9, 3 cytochrome-C, APAF-1, Bax, perforin-1 and granzyme-B on Treg cells which is decreased following intranasal immunotherapy. On the other hand, Bcl-2 expression is decreased in allergy and increased by immunotherapy.

CONCLUSION

Apoptosis of Treg cells is increased following allergen sensitization-challenge via extrinsic, intrinsic and perforin/granzyme pathways and allergen immunotherapy decreased the sensitivity to apoptosis of Treg cells.

Sensitivity to House Dust Mites Allergens with Atopic Asthma and Its Relationship with CD14 C(-159T) Polymorphism in Patients of West Bengal, India

India is the home to around 15-20 million asthmatics, and asthma prevalence is increasing in Indian metropolitan area, including Kolkata, West Bengal. Complex interactions of genetic and environmental factors are involved in asthma. Genome-wide search for susceptible loci regulating IgE response (atopy) have identified a candidate gene CD14 which is most important in the context of allergic responses of respiratory system. This study was aimed to investigate the role of house dust and house dust mites in development of bronchial asthma and to explore the possible association of candidate gene CD14 with disease manifestation among Kolkata patient population. Skin-prick test was done among 950 asthmatic patients against 8 aeroallergens, including house dust and house dust mites and total serum IgE and allergen-specific IgE were measured. Polymerase chain reaction-restriction fragment length polymorphism was done in patients and nonasthmatic control (n = 255 in each) to characterize a functional polymorphism, C(-159)T, of CD14, a positional candidate gene for allergy. We identified house dust as the most common aeroallergen sensitizer among atopic patients in Kolkata followed by Dermatophagoides pteronyssinus and Dermatophagoides farinae Hughes (Acari: Pyroglyphidae) mites. Patient's sera contain significantly higher IgE level than that of control. Allergen-specific IgE antibody test revealed that 76.36% patients had specific IgE antibody against D. pteronyssinus mite. There was a significant difference in the distribution of alleles and genotypes for CD14 polymorphism with an increase in disease severity. So, in Kolkata, house dust mite is a common aeroallergen and D. pteronyssinus is predominant among mites. The present study revealed that bronchial asthma has a genetic background.

Role of offending out-door aero-allergen and CD14 C(-159)T polymorphism in development and severity of asthma in a Kolkata patient population

Objective

Present study involved identification of offending out-door aero-allergens and associated genetic pathway in nasso-bronchial asthma among Kolkata population.

Methods

Skin-prick test was done among 950 asthmatic patients against 11 common aero-allergens and total serum IgE concentration was measured. PCR-RFLP was done in patients and non-asthmatic control (n=220 in each) to characterize functional polymorphism, C(-159)T, of CD14, a positional candidate gene for allergy. Association of genetic polymorphisms was made with clinico-pathological conditions.

Results

We identified Cocos nucifera as the most common aero-allergen sensitizer among atopic patients in Kolkata. Patients with childhood-onset asthma were significantly more sensitive towards aero-allergens and had significantly higher serum IgE level than those of adult-onset (p< 0.0001). No significant difference was found in distribution of SNP genotypes of CD14 among case and control (p=0.178). However among patients, frequency of C allele is significantly higher in childhood-onset group than that of adult-onset and concordantly in former CC genotype was associated with significant higher level of serum IgE than CT and TT.

Conclusion

In Kolkata, pollen is a common out-door aero-allergen and Cocos nucifera is predominant among pollens. Childhood-onset and adult-onset of asthma showed significant difference in allergen sensitivity as well as genetic background with respect to CD14 polymorphism.

Respiratory Morbidity among Indian Tea Industry Workers

Background:

Indian tea industry workers are exposed to various exposures at their workplace.

Objective:

To investigate the respiratory health of Indian tea industry workers.

Methods:

We administered a respiratory questionnaire to and measured lung function in workers of 34 tea gardens and 46 tea factories. We used correlation matrices to test the association between their respiratory symptoms and lung functions.

Results:

The garden workers complained of shortness of breath 3 times higher than the factory workers. However, nasal allergy was more predominant among the factory workers compared to garden workers (69.6% vs 41.2%, p=0.02). The factory workers had higher total (median 107.3% vs 92.9%, p=0.05, as measured by R at 5 Hz) and peripheral airway resistance (143.8% vs 61.1%, p=0.005, as measured by R at 5–20 Hz) than the garden workers. Respiratory symptoms were inversely associated with airway obstruction as measured by the ratio between forced expiratory volume in 1 second (FEV₁) and forced vital capacity (FVC) and positively correlated with increased overall airway reactance among the workers.

Conclusion:

Respiratory symptoms and increased allergen susceptibility of Indian tea industry workers due to occupational exposures warrant routine systematic surveillance of their workplace air quality and health monitoring.

Modulation of regulatory T cells by intranasal allergen immunotherapy in an experimental rat model of airway allergy

Allergic airway diseases such as asthma and allergic rhinitis are increasing in prevalence worldwide. The theory of an altered Th1/Th2 balance in allergic diathesis has recently been termed a "procrustean paradigm" as it failed to explain many preclinical findings. Regulatory T cells (Treg) have now been shown to be critical in T-cell homeostasis and in the maintenance of peripheral tolerance to allergens. Allergen specific immunotherapy (SIT) has been shown to induce regulatory T cells in allergic patients. Among various types of SIT, intranasal immunotherapy had not been studied in detail for the treatment of allergic airway diseases. So, there was a need to study the contribution of regulatory T cells and their mechanistic pathways following intranasal immunotherapy in-vivo. It had been previously shown that intranasal allergen immunotherapy using Alstonia scholaris pollen extract abrogates allergic airway inflammation with decline in IgE and Th2 cytokine levels. The present study for the first time offers a multi-targeted approach towards attenuation of airway allergy by the generation of CD4+CD25+Foxp3+T cells and other subsets of Treg cells like Tr1 cells, Th3 cells, CTLA4+Treg cells, and also modulation of various Treg cell surface molecules like GITR, OX40, CD39 and CD73 by intranasal immunotherapy in the same animal model. This animal experiment will thus help to chart out newer molecular targets for treating allergic asthma or rhinitis.