Naren Pandey

Search for Allergens from the Pollen Proteome of Sunflower (Helianthus annuus L.): A Major Sensitizer for Respiratory Allergy Patients

Background Respiratory allergy triggered by pollen allergens is increasing at an alarming rate worldwide. Sunflower pollen is thought to be an important source of inhalant allergens. Present study aims to identify the prevalence of sunflower pollinosis among the Indian allergic population and characterizes the pollen allergens using immuno-proteomic tools. Methodology Clinico-immunological tests were performed to understand the prevalence of sensitivity towards sunflower pollen among the atopic population. Sera from selected sunflower positive patients were used as probe to detect the IgE-reactive proteins from the one and two dimensional electrophoretic separated proteome of sunflower pollen. The antigenic nature of the sugar moiety of the glycoallergens was studied by meta-periodate modification of IgE-immunoblot. Finally, these allergens were identified by mass-spectrometry. Results Prevalence of sunflower pollen sensitization was observed among 21% of the pollen allergic population and associated with elevated level of specific IgE and histamine in the sera of these patients. Immunoscreening of sunflower pollen proteome with patient sera detected seven IgE-reactive proteins with varying molecular weight and pI. Hierarchical clustering of 2D-immunoblot data highlighted three allergens characterized by a more frequent immuno-reactivity and increased levels of IgE antibodies in the sera of susceptible patients. These allergens were considered as the major allergens of sunflower pollen and were found to have their glycan moiety critical for inducing IgE response. Homology driven search of MS/MS data of these IgE-reactive proteins identified seven previously unreported allergens from sunflower pollen. Three major allergenic proteins were identified as two pectate lyases and a cysteine protease. Conclusion Novelty of the present report is the identification of a panel of seven sunflower pollen allergens for the first time at immuno-biochemical and proteomic level, which substantiated the clinical evidence of sunflower allergy. Further purification and recombinant expression of these allergens will improve component-resolved diagnosis and therapy of pollen allergy.

A Hospital-Based Survey on Food Allergy in the Population of Kolkata, India

Background: Food allergy is increasing worldwide, and Asian countries are not the exception. Still, ample data are lacking in India. We conducted a cross-sectional study in a metropolis of Eastern India to record the presence of food allergy among the local population. Methods: The prevalence of food allergy was investigated among patients reporting to The Institute of Child Health and Mediland Diagnostics in Kolkata, India. A total of 5,161 patients were subdivided into 3 age groups and surveyed accordingly. The evaluation was conducted via a questionnaire and a skin prick test. Results: Among the 5,161 patients tested, 4,160 showed a positive response to one or more food items. Banana (32%), brinjal (29%), wheat (22%), and egg (23%) were found to be dominant allergens. Sixty-three percent of patients with a family history of allergy showed either a sudden or an insidious mode of onset, whereas the remaining 37% suffered insidious allergic symptoms with no record of a family history of allergy. Skin rashes, cough, and sneezing were the major symptoms observed. Patients in the age group of 15-40 years were the most susceptible. Conclusion: It has been observed that certain specific foods consumed in specific regions cause allergies that are unique to their respective populations. In the present study, the most commonly consumed foods in the studied area, e.g. banana, brinjal, wheat, and egg, had severe effects on the local population. Complementary studies in other countries as well as in other parts of India will allow us to gain further insight into this fact. Some other influencing factors were found to be genetics, cultural habits, and occupation. Avoidance of the allergy-causing food is the best way to deal with food allergy.

Purification, Cloning and Immuno-Biochemical Characterization of a Fungal Aspartic Protease Allergen Rhi o 1 from the Airborne Mold Rhizopus oryzae.

Background Fungal allergy is considered as serious health problem worldwide and is increasing at an alarming rate in the industrialized areas. Rhizopus oyzae is a ubiquitously present airborne pathogenic mold and an important source of inhalant allergens for the atopic population of India. Here, we report the biochemical and immunological features of its 44 kDa sero-reactive aspartic protease allergen, which is given the official designation ‘Rhi o 1’. Method The natural Rhi o 1 was purified by sequential column chromatography and its amino acid sequence was determined by mass spectrometry and N-terminal sequencing. Based on its amino acid sequence, the cDNA sequence was identified, cloned and expressed to produce recombinant Rhi o 1. The allergenic activity of rRhi o 1 was assessed by means of its IgE reactivity and histamine release ability. The biochemical property of Rhi o 1 was studied by enzyme assay. IgE-inhibition experiments were performed to identify its cross-reactivity with the German cockroach aspartic protease allergen Bla g 2. For precise characterization of the cross-reactive epitope, we used anti-Bla g 2 monoclonal antibodies for their antigenic specificity towards Rhi o 1. A homology based model of Rhi o 1 was built and mapping of the cross-reactive conformational epitope was done using certain in silico structural studies. Results The purified natural nRhi o 1 was identified as an endopeptidase. The full length allergen cDNA was expressed and purified as recombinant rRhi o 1. Purified rRhi o 1 displayed complete allergenicity similar to the native nRhi o 1. It was recognized by the serum IgE of the selected mold allergy patients and efficiently induced histamine release from the sensitized PBMC cells. This allergen was identified as an active aspartic protease functional in low pH. The Rhi o 1 showed cross reactivity with the cockroach allergen Bla g 2, as it can inhibit IgE binding to rBla g 2 up to certain level. The rBla g 2 was also found to cross-stimulate histamine release from the effector cells sensitized with anti-Rhi o 1 serum IgE. This cross-reactivity was found to be mediated by a common mAb4C3 recognizable conformational epitope. Bioinformatic studies revealed high degree of structural resemblances between the 4C3 binding sites of both the allergens. Conclusion/Significance The present study reports for the first time anew fungal aspartic protease allergen designated as Rhi o 1, which triggers IgE-mediated sensitization leading to various allergic diseases. Here we have characterized the recombinant Rhi o 1 and its immunological features including cross-reactive epitope information that will facilitate the component-resolved diagnosis of mold allergy.

Biomonitoring of pollen grains of a river bank suburban city, Konnagar, Calcutta, India, and its link and impact on local people

INTRODUCTION AND OBJECTIVES Pollen grains released by plants are dispersed into the air and can become trapped in human nasal mucosa, causing immediate release of allergens triggering severe Type 1 hypersensitivity reactions in susceptible allergic patients. Recent epidemiologic data show that 11-12% of people suffer from this type of disorders in India. Hence, it is important to examine whether pollen grains have a role in dissipating respiratory problems, including allergy and astma, in a subtropical suburban city. MATERIALS AND METHODS Meteorological data were collected for a period of two years, together with aerobiological sampling with a Burkard sampler. A pollen calendar was prepared for the city. A health survey and the hospitalization rate of local people for the above problems were documented following statistical analysis between pollen counts and the data from the two above-mentioned sources. Skin Prick Test and Indirect ELISA were performer for the identification of allergenic pollen grains. RESULTS Bio-monitoring results showed that a total of 36 species of pollen grains were located in the air of the study area, where their presence is controlled by many important meteorological parameters proved from SPSS statistical analysis and by their blooming periods. Statistical analysis showed that there is a high positive correlation of monthly pollen counts with the data from the survey and hospital. Biochemical tests revealed the allergic nature of pollen grains of many local species found in the sampler. CONCLUSIONS Bio-monitoring, together with statistical and biochemical results, leave no doubt about the role of pollen as a bio-pollutant. General knowledge about pollen allergy and specific allergenic pollen grains of a particular locality could be a good step towards better health for the cosmopolitan suburban city.

Data on mass spectrometry based identification of allergens from sunflower (Helianthus annuus L.) pollen proteome

Allergy is a type of abnormal immune reactions, which is triggered by environmental antigens or allergens and mediated by IgE antibodies. Now-a-days mass spectrometry is the method of choice for allergen identification based on homology searching. Here, we provide the mass spectrometry dataset associated with our previously published research article on identification of sunflower pollen allergens (Ghosh et al., 2015 [1]). In this study allergenicity of sunflower (Helianthus annuus) pollen grains were primarily investigated by clinical studies followed by detailed immunobiochemical and immunoproteomic analyses. The mass spectrometry data for the identification of allergens were deposited to ProteomeXchange Consortium via PRIDE partner repository with the dataset identifier PXD002397.

Burden and Socio-Behavioral Correlates of Uncontrolled Abnormal Glucose Metabolism in an Urban Population of India

Background Progressive burden of diabetes mellitus is a major concern in India. Data on the predictors of poor glycemic control among diabetics are scanty. A population-based cross-sectional study nested in an urban cohort was thus conducted in West Bengal, India to determine the burden and correlates of total and uncontrolled abnormalities in glucose metabolism (AGM) in a representative population. Methods From 9046 adult cohort-members, 269 randomly selected consenting subjects (non-response = 7.24%) were interviewed, examined [blood pressure (BP), anthropometry], tested for fasting plasma glucose (FPG) and glycosylated hemoglobin (HbA1C). Those having pre-diagnosed diabetes or FPG ≥126 or HbA1c≥6.5 were defined as diabetic. Among non-diabetics, subjects with FPG (mg/dl) = 100–125 or HbA1C(%) = 5.7–6.4 were defined as pre-diabetic. Pre-diagnosed cases with current FPG ≥126 were defined as uncontrolled AGM. Descriptive and regression analyses were conducted using SAS-9.3.2. Results Among participants, 28.62% [95% Confidence Interval (95%CI) = 23.19–34.06)] were overweight [body mass index(BMI) = (25–29.99)kg/meter2], 7.81% (4.58–11.03) were obese(BMI≥30kg/meter2), 20.82% (15.93–25.70) were current smokers, 12.64% (8.64–16.64) were current alcohol-drinkers and 46.32% of responders (39.16–53.47) had family history of diabetes. 17.84% (13.24–22.45) had stage-I [140≤average systolic BP (AvSBP in mm of mercury)<160 or 90≤average diastolic BP (AvDBP)<100] and 12.64% (8.64–16.64) had stage-II (AvSBP≥160 or AvDBP≥160) hypertension. Based on FPG and HbA1c, 10.41% (6.74–14.08) were diabetic and 27.88% (22.49–33.27) were pre-diabetic. Overall prevalence of diabetes was 15.61% (11.25–19.98). Among pre-diagnosed cases, 46.43% (26.74–66.12) had uncontrolled AGM. With one year increase in age [Odds Ratio(OR) = 1.05(1.03–1.07)], retired subjects [OR = 9.14(1.72–48.66)], overweight[OR = 2.78(1.37–5.64)], ex-drinkers [OR = 4.66(1.35–16.12)] and hypertensives [ORStage I = 3.75(1.42–9.94); ORStage II = 4.69(1.67–13.17)] had higher odds of diabetes. Relatively older subjects [OR = 1.06(1.02–1.10)], unemployed [OR = 19.68(18.64–20.78)], business-owners [OR = 25.53(24.91–16.18)], retired [OR = 46.53(45.38–47.72)], ex-smokers [OR = 4.75(1.09–20.78)], ex-drinkers [OR = 22.43(4.62–108.81)] and hypertensives [ORStage II = 13.17(1.29–134.03)] were more likely to have uncontrolled AGM. Conclusions Burden of uncontrolled AGM was high among participants. Efforts to curb the diabetes epidemic in urban India should include interventions targeting appropriate diabetic control among relatively older persons, unemployed, business-owners, retired, ex-smokers, ex-drinkers and hypertensives.

Environmental and occupational respiratory diseases – 1046. Lung function among the workers exposed to rubber factory in West Bengal

Methods The study was carried out on the 256 workers exposed to dust at the rubber factory. 16 workers with moderate exposure, 240 Workers with high exposure, spirometry (FVC, FEV1) were performed. Information on occupational history, duration of exposure, smoking habits, alcohol consumption, respiratory symptoms (breathlessness, cough and rhinitis) and self reported symptoms with disease were collected. By employing multiple linear regression modeling the potentially confounding effects of age, sex and body mass index were also incorporated into the analysis. Odds ratio were calculated for FVC<80% predicted in different exposure subgroups.