Asia Pacific Association of Allergy Asthma and Clinical Immunology White Paper 2020 on climate change, air pollution, and biodiversity in Asia-Pacific and impact on allergic diseases

Air pollution, climate change, and reduced biodiversity are major threats to human health with detrimental effects on a variety of chronic noncommunicable diseases in particular respiratory and cardiovascular diseases. The extent of air pollution both outdoor and indoor air pollution and climate change including global warming is increasing-to alarming proportions particularly in the developing world especially rapidly industrializing countries worldwide. In recent years, Asia has experienced rapid economic growth and a deteriorating environment and increase in allergic diseases to epidemic proportions. Air pollutant levels in many Asian countries especially in China and India are substantially higher than are those in developed countries. Moreover, industrial, traffic-related, and household biomass combustion, indoor pollutants from chemicals and tobacco are major sources of air pollutants, with increasing burden on respiratory allergies. Here we highlight the major components of outdoor and indoor air pollutants and their impacts on respiratory allergies associated with asthma and allergic rhinitis in the Asia-Pacific region. With Asia-Pacific comprising more than half of the world's population there is an urgent need to increase public awareness, highlight targets for interventions, public advocacy and a call to action to policy makers to implement policy changes towards reducing air pollution with interventions at a population-based level.

Detecting Allergens From Black Tiger Shrimp Penaeus monodon That Can Bind and Cross-link IgE by ELISA, Western Blot, and a Humanized Rat Basophilic Leukemia Reporter Cell Line RS-ATL8

BACKGROUND: Black tiger shrimp Penaeus monodon is one of the common causes of shellfish allergy that is increasing worldwide. One of the important problems in the management of shellfish allergy is the lack of accurate diagnostic assay because the biological and immunological properties of allergens in black tiger shrimp have not been well characterized. This study aims to detect proteins with the ability to bind and cross-link immunoglobulin E (IgE) from black tiger shrimp by enzyme-linked immunosorbent assay (ELISA), Western blot, and a humanized rat basophilic leukemia reporter cell line RS-ATL8. METHODS: Sera from shrimp allergic subjects were subjected to ELISA and Western blots using raw or cooked shrimp extract as antigens. Pooled sera were used to sensitize the RS-ATL8 reporter cell line and cells were activated by shrimp extract. Eluted protein extracts separated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were tested on the RS-ATL8 cell line and subjected to mass spectrometry to identify potential candidate allergens. RESULTS: Allergic sera reacted stronger to raw shrimp extract than cooked shrimp extract (P=0.009). Western blot demonstrated that major IgE reactivity protein bands were at 32–39 kDa and 91–230 kDa in both raw and cooked shrimp extracts. The eluted protein bands at the molecular weight of 38 and 115 kDa from raw shrimp extract induced IgE cross-linking as assayed by the RS-ATL8 cell line. These protein bands were subjected to mass spectrometry for analysis. Ubiquitin-activating enzyme and crustacyanin were identified as potential candidate novel shrimp allergens. CONCLUSIONS: The RS-ATL8 reporter cell line can be used to identify potential new shrimp allergens that can functionally cross-link IgE and induce mast cell degranulation.

The efficacy of partially hydrolyzed formulas for allergy prevention in children under five years

Background: Recommendations for allergy prevention in children include feeding with partially hydrolyzed formulas if breast-feeding is not possible or insufficient. Objective: The primary objective of this study was to investigate the allergy preventive effect of partially hydrolyzed formulas compared with cow's milk formulas and breast-feeding during the first five years of life in a retrospective randomized trial. Methods: A retrospective, large-scale intervention study of 3,502 unselected children aged between one and five years recruited between April 2005 and March 2006 was performed. Main outcome parameters were allergic manifestations including cow's milk allergy, atopic dermatitis (AD), chronic rhinitis, and recurrent wheeze. Results: About 35.2% developed allergic manifestations mostly during the first year of life. More males developed atopic diseases than females (OR=1.5; 95%CI=1.300-1.719). Compared with the breast-feeding group, the occurrence of atopic diseases significantly increased in the cow's milk formula group (OR=1.66; 95%CI=1.396-1.957) while it decreased in the partially hydrolyzed formula (pHF) group (OR=0.23; 95%CI=0.160-0.314) during the first four years of life. Considering the risk for the development of atopic diseases determined by atopic risk score, there was a positive association between the high risk score children compared to the low risk ones in both the breast-feeding group and the cow's milk formula group. However, there was no significant association in the pHF group. Compared with the breast-feeding group, the risk estimate for the development of atopic diseases was significantly increased in children with high risk score in the cow's milk formula group but was reduced in the pHF group. Conclusion: The risk of atopic diseases can be reduced with partially hydrolyzed formula in high-risk infants when breast-feeding is insufficient.

Clinical and molecular characteristics of Thai families with autosomal recessive chronic granulomatous disease

Background: Autosomal recessive chronic granulomatous disease (AR-CGD) is an inherited defect in neutrophil oxidative burst as a result of mutations in one of the three genes, NCF1, NCF2, and CYBA, which respectively encode p47-phox, p67-phox, and p22-phox subunits of the NADPH oxidase complex.Objective: To investigate clinical and molecular characteristics of two unrelated Thai patients with AR-CGD.Methods: A Thai girl who suffered from pulmonary aspergillosis at the age of two months and another unrelated Thai boy presented with recurrent cutaneous abscesses caused by Chromobacterium violaceum since 30 months old, were investigated. The DHR assays revealed abnormalities in both patients but normal results in their mothers, consistent with the diagnosis of AR-CGD. PCR-sequencing of the entire coding regions of NCF1, NCF2, and CYBA was performed.Results: A homozygous c.75_76delGT mutation at the beginning of exon 2 of NCF1 was identified in both individuals. This mutation resulted in a frameshift with premature termination of p47-phox at codon 51 (p.Val25fsX51).Conclusion: The homozygous GT deletion in NCF1 may be a common mutation in Thai patients with AR-CGD. Unlike all other autosomal recessive disorders, AR-CGD caused by NCF1 mutations has a unique mutational pattern, in which there is only one mutation responsible for most patients regardless of their ethnic backgrounds.

Sensitivity and specificity of MAST chemiluminescence assay of allergen-specific immunoglobulin in allergic Thai children: comparison to the skin prick test

Background and objective: The prevalence of allergic diseases is increasing in Thailand. For the diagnosis of allergic disease, in-vivo and in-vitro clinical tests are required. This paper examined the effectiveness of multiple allergosorbent test (MAST) chemiluminescence assay (CLA) technique of serum allergen-specific immunoglobulin (IgE) in allergic Thai children by comparing the sensitivity and specificity to the skin prick test. Methods: One-hundred children with allergic diseases (age: 3-18 years old; 62 male and 38 female) were included. The diagnosis of allergy was based on patient history, physical finding, and skin prick test. Fourteen allergens (6 aeroallergens and 8 food allergens) were tested for this study. Allergen-specific IgE test was performed in patient serum using the MAST CLA technique Optigen Universal Panel 20. The food allergens were mixed-shellfish, shrimp, mixed-fish, cow milk, peanut, egg white, wheat, and soybean. The results by the skin prick test and the MAST CLA were graded into five levels (0-4), where level 3 and 4 were defined positive and levels 0-2 negative. Results: In the skin prick test, the following aeroallergens were positive: Dermatophagoides pteronyssinus, Dermatophagoides farinae, cockroach (German, American or mixed) and cat, as well as some for food allergens such as mixed-shellfish, shrimp, cow milk, and mixed-fish. In the allergen-specific IgE by MAST CLA, the following aeroallergens were positive: Dermatophagoides pteronyssinus, Dermatophagoides farinae, cat, cockroach-mix and dog. Food allergens were positive for cow milk, wheat, egg white, peanut and soybean. The sensitivity and specificity of the MAST CLA against the skin prick test was more than 50%, while the specificity was more than 88%. The result with the 14 allergen commercial panel combination showed that the sensitivity and specificity was highest. Conclusions: The MAST CLA for the in-vitro determination of allergen-specific IgE in patient serum can be used for screening and diagnosis of allergic Thai children.

Atopic risk score for allergy prevention

Background: There have been recommendations for allergy prevention in cases of high risk infants; nevertheless, there has been no definite criterium to identify those at risk. Objective: To develop an atopic risk score to identify infants who are at risk and deserve allergy prevention by noting a history of atopic diseases of their 1st degree related family. The scoring is weighted by genetic correlation to each atopic disease to determine the score that is the most appropriate for predictive screening for the development of atopic diseases. Method: This is a retrospective study designed by a team of family pediatricians. Three-thousands five-hundred two children aged 1-5 years from Bangkok and other provinces of Thailand were included between April 2005 and March 2006. From their clinics, the family pediatricians recorded the patients’ family history of atopic diseases by using the atopic risk score that had been designed, and the health status that had been recorded in the past one-five years. Main outcome parameters were allergic manifestations including cow’s milk allergy, atopic dermatitis (AD), chronic rhinitis, and recurrent wheeze. Results: Study subjects were 3,502 children; female (56.4%) and male (43.6%) attending health care facilities in Bangkok and other provinces. The average age of onset of atopic disease was 14.7 months (2 weeks to 5 years) with the median age 9 months. 35.2% had developed atopic diseases mostly during the first year of life (78.3%) and had either a positive or negative family history of atopy. Male children developed significantly more atopic disease than the female with P value \< 0.001 (OR=1.5; 95%CI=1.300-1.719). The association of the atopic risk score with the development of atopic diseases was determined by using odds ratio as risk estimates. All scores from score one were associated significantly with the development of atopic diseases by OR=2.64-3.22 with p-value \< 0.001 and 95%CI. The score that could be used for screening of the high-risk infant, was more than 2. Conclusion: The atopic risk score is a practical method to identify the infants with high risk who deserve allergy prevention.