The most common aeroallergens in a tropical region in Southwestern Iran

Evaluation of The Safety and Efficacy of Newly Developed Domestic Allergenic Extracts for Skin Prick Testing

Background

Allergic disorders are common health problems worldwide with significant socio-economic impacts. The best diagnostic method using allergenic extract is the skin prick test. Regarding the effects of geo-climatic factors and allergenic extract source material quality, the aim of study was to determine the safety and efficacy of some in-house-developed allergenic extracts.

Methods

Forty-five different allergenic extracts, including common regional pollen, foods, and dog and cat hair, as well as positive and negative extracts, were prepared from domestic sources using optimum extraction methods. All extracts passed stability and sterility testing, and sterile final products containing 50% glycerin in 10 and 20 w/v concentrations were used. Skin prick testing was performed on volunteers and immediate or late side effects were recorded.

Results

In total, 56 students (mean age: 21.2±2.3y, M/F ratio: 1.07) participated in this study. For inhalant allergens, all extracts except dog hair extract caused positive responses. Salsola kali (Russian thistle) and Fraxinus velutina (ash tree) were the most common grass and tree pollen extracts, respectively. Of 18 different food extracts, five, including egg white, tomato, fig, melon, and green pepper caused skin reactivity in only one person. No participant reported any immediate or late side effects, including large local reaction or systemic response.

Conclusion

The result of the current study confirmed the safety of all our in-house-developed allergenic extracts. Regarding efficacy, almost all inhalant and five food allergens caused positive skin responses.

The Influence of Indoor Environmental Factors on the Prevalence of House Dust Mites as Aeroallergens in Bandar Abbas Student Dormitories, South of Iran, 2019

This study was conducted to determine the influence of environmental factors on the prevalence of house dust mites in student dormitories of Bandar Abbas city. In this study, 64 dust samples were collected from seven randomly selected dormitories located in various areas of the Bandar Abbas. The collected mites were isolated and mounted in Hoyer's medium and identified using a morphological key. The associations between the environmental factors and the density of house dust mites were investigated. In total, 1,093 adult mites were collected and identified. They consisted of four species including Dermatophagoides pteronyssinus Trouessart (57.6%), Dermatophagoides farinae Hughes (24.3%) and Dermatophagoides evansi Fain (14.9%) (Acari: Pyroglyphidae), and Cheyletus malaccensis Oudemans (3.2%) (Acari: Cheyletidae). All of the dormitories were contaminated by more than one house dust mites species and the mean density of house dust mites in dormitories was 8.3 ± 0.2 mites/g of dust. There was a significant relationship between average house dust mites density and some of environmental factors such as relative humidity, temperature, floor covering type, and number of occupants (P < 0.05). Results of this study revealed that two major allergenic dust mites, D. pteronyssinus and D. farinae, were the most prevalent and collected from all of dormitories and some of indoor environmental factors found to influence mites' population.

Sensitization to Inhaled Allergens in Atopic Children in Jordan Capital, Amman: A Cross-sectional Study

Background:

As the prevalence of allergic diseases is increasing all over the world, it is vital to identify the specific allergens, which contribute to the development and persistence of such conditions.

Objectives:

This study aims to assess the prevalence of aeroallergen sensitization and, to evaluate the profile of skin prick test among atopic Jordanian children who are visiting Jordan University Hospital (JUH).

Methods:

A retrospective analysis of all Skin Prick Test (SPT) and results of atopic children and adolescents aged (1.5-18 years) who visited the pediatrics clinics at JUH from January 2018 until December 2019.

Results:

Over two years, a total of 171 children (male: female ratio of 1.9) with a median age of 6.2 years (1.5-18) were subjected to SPT. One hundred and seven children (62.5%) were found to be sensitized to at least one of the ten aeroallergen extracts tested. The most common sensitizations were to olive pollen (45.6%), Mites Dermatophagoides Petronyssinus (42.0%), and Dog Dander (38.6%). The highest sensitization rate was among the age group 2-4 years (28.1%). The sensitization rates increased in conjunction with an increase in age in the first age groups (preschool and school-age groups).

Conclusion:

The study’s findings provide an understanding of the locally prevalent aeroallergens, yet a multi-center review would be more useful for creating an optimized SPT panel specific to the Jordanian pediatric population.

Aeroallergen sensitisation patterns of children aged 5 years and younger with asthma and/or allergic rhinitis in Istanbul

AIM OF THE STUDY

The purpose of the study was to determine the aeroallergen sensitisation patterns of children aged 5 years and younger with asthma (AS) and/or allergic rhinitis (AR) in Istanbul, Turkey.

METHODS

This cross-sectional observational study was conducted between January and December 2018 in the outpatient clinic of a hospital department of pediatric allergy. Patients, who had regular outpatient controls, full clinical and laboratory records, positive skin prick test results, and were willing to participate in the study, were included.

RESULTS

In total, 148 children aged 5 years or younger who had positive skin prick test results were included in the study. The male/female ratio and the mean age at onset of symptoms were 87/61 and 2.13±1.33 (0.4-4.5) years, respectively. Of the 148 patients, 63 (42.6%) had AS, 11 (7.4%) AR, and 74 (50.0%) had both AS and AR. The age of the patients, age at symptom onset, male/female ratio, number of allergen sensitivities, total IgE levels, total eosinophil levels, and skin prick test results for aeroallergens did not differ between the patients with AS, AR, and AS+AR. House dust mite (HDM) was the most common aeroallergen in patients, while the cockroach was the least common aeroallergen. The severity of asthma and control levels were not found to be associated with aeroallergen sensitisation in children.

CONCLUSION

One out of every four atopic children aged 5 years or younger is sensitised to aeroallergens. The most common sensitisation is to house dust mites. Weed aeroallergen may be related to severity of asthma in children aged 5 years or younger in Istanbul. We speculate that HDM and weed allergens could be used in the diagnostic or treatment strategies for the management of asthmatic children aged 5 years or younger.

Allergic rhinitis: Disease characteristics and coping measures in Saudi Arabia

BACKGROUND

Despite allergic rhinitis (AR) being a highly prevalent disease, according to literature, it is often underdiagnosed or undertreated.

AIM

This study explored the disease characteristics of AR in the Saudi community and the non-conventional coping measures used to alleviate symptoms.

METHODS

The study was a nationwide cross-sectional study, using a self-report electronic survey distributed via social media networks in 2018. The survey included an explanatory letter and consent. The sample size comprised 3,458 participants and 2,849 adults had at least one of the four signs of AR, i.e. watery-nose, sneezing, nasal obstruction, itchy nose, watery eyes, in the past year, not related to cold/flu. The outcomes of the study were the triggers, pattern, severity and the classification of AR (2016 ARIA guidelines) and coping measures. Descriptive statistics, univariate analytic statistics and binary logistic regression analyses were conducted. The P-value was considered statistically significant at <0.05.

RESULTS

The leading reported trigger of AR was dust (74%, n = 2118), followed by pollen (17%, n = 477), mold (5%, n = 140) and fur (4%, n = 114). The prevalence of intermittent AR was (54%, n = 1,635), while that of persistent AR was (46%, n = 1,314). Almost one-third (34%, n = 959) complained of mild forms of AR, while others complained of moderate to severe forms (66%, n = 1890). The coping measures were mainly shower/humidification 368(12.9%) and herbal hot drinks 266(9.3%). Older participants (adj.OR = 1.3[1.1-1.5]) and overweight participants, (adj.OR = 1.2[1.1-1.4]) reported more persistent forms of rhinitis compared to their counter groups, (adj.P<0.001 and adj.P = 0.032) respectively. Female participants (adj.OR = 0.8[0.7-0.9]) had significantly milder forms of AR, in comparison to males, adj.P = 0.006.

CONCLUSION

This study presented the disease characteristics of self-reported AR and its associated factors in Saudi Arabia. Special attention should be paid to older age groups and overweight patients who reported persistent forms of AR. Males reported more severe and persistent forms of AR.

The Most Common Allergenic Tree Pollen Grains in the Middle East: A Narrative Review

Allergy is becoming a major disease burden globally. Pollens are considered as the main component of aeroallergens that lead to rhinitis and asthma. Due to the lack of a comprehensive investigation on most allergic pollens of trees in the Middle East, the present study aimed to conduct a comprehensive literature review on this topic. The main goal of the study was to provide a checklist for allergists and patients to easily identify the commonest allergic pollens in their locality. The present review provides a broad range of information on the types and geographic locations of the most common allergic pollens of trees in each studied country. In general, among the 23 studied countries, palm and mesquite trees were the common producers of pollen allergen in the Persian Gulf region. Olive tree is common in Turkey, Palestine, and Israel, whereas sycamore tree is the common allergen pollen in Iran. Considering the uneven geographical distribution of these trees in the world, allergists are unable to accurately select the appropriate extracts for the skin prick test based on the information from the neighboring countries. This scenario becomes more complicated if one adds the imported ornamental trees in the picture.

A review on hypersensitivity reactions to fungal aeroallergens in patients with allergic disorders in Iran

Fungal agents account for the clinical manifestation of allergic disorders. The aim of the present study was to review the prevalence of hypersensitivity reactions to fungal aeroallergens in patients with allergic disorders, including allergic rhinitis, asthma, urticaria, and eczema, in Iran. The initial literature search resulted in the identification of 50 records, 26 cases of which met the inclusion criteria. Regarding the methods adopted for the detection of fungal allergens, serum-specific IgE and skin prick tests were used in 6 and 20 studies, respectively. Aspergillus fumigatus and Alternaria alternata sensitization was the most common allergic sensitization among the patients with allergic disorders. According to the reviewed studies, despite the humid climate of the north of Iran, fungal sensitization has a prevalence range of 5-70% in this region. In other regions, such as central and southern Iran, which have a dry and warm climate, fungal sensitization reportedly has a prevalence range of 5-65%. The prevalence of fungal sensitizations varies in different allergic disorders due to the factors related to geographic and genetic issues, gender, sample size, test operator, and assessment method.

Allergens Prevalence among Patients with Respiratory Allergies in Mashhad, Iran

BACKGROUND

Respiratory allergies are among the most common allergies in the world with an increasing number of people affected in recent decades. Determination of allergens prevalence in each area is considered as the first step in prevention of allergic diseases and developing novel and more effective immunotherapies. The aim of this study was to determine the prevalence of the most common allergens among patients with respiratory allergies in Mashhad, Iran.

MATERIALS AND METHODS

This cross sectional study included 1246 people who were referred to Allergy Clinic of Mashhad University of Medical Sciences with respiratory allergic symptoms from 2012 to 2017 in which a questionnaire containing demographic information was completed and Skin Prick Test was performed for each patient.

RESULTS

Among 1246 patients with respiratory symptoms, there were 1084 patients with allergic rhinitis (87%), 69 patients with allergic asthma (5.5%), 14 patients with allergic rhinoconjunctivitis (1.1%) and 79 patients with both allergic rhinitis and asthma (6.3%) with an overall male to female ratio of 1.18. Rhinorrhea (86.3%), sneezing (81.1%) and itchy eyes (68.4%) were the most common symptoms in patients with respiratory allergic disorders in this study and the highest rate of sensitivity was to pollens including Salsola kali (82.3%), pigweed mix (65.1%), tree mix (51.7%) and ash (49.8%), respectively.

CONCLUSION

Generally, Salsola kali seems to be the main allergen in different respiratory allergies including allergic rhinitis, asthma and rhinoconjunctivitis in semi-arid climate of Mashhad, Iran.

House dust mites among allergic patients at the Allergy and Immunology Unit, Zagazig University: an immunologic and serologic study

In the twenty-first century, the occurrence of allergic diseases has increased. Prevention and control of house dust mites (HDMs) are required as they play a major role in allergic conditions. The present work aimed to detect HDM allergy (Dermatophagoides pteronyssinus and Dermatophagoides farinae) among allergic patients attending the Allergy and Immunology Unit, Zagazig University. Ninety-six patients with a history of allergic diseases were included in this study. They were examined for allergy to D. pteronyssinus and D. farinae using different diagnostic tools: the skin prick test (SPT) and measurement of specific IgE antibodies to HDM allergen extracts. Ninety-six allergic patients were recruited in this study [60 females (62.5%) and 36 males (37.5%) aged between 5-60 years]. SPT (81.2 and 79.2%) and IgE (70.9 and 75%) gave positive results for both D. pteronyssinus and D. pteronyssinus, respectively. The common risk factors were use of cotton bedding > 10 years old, older homes > 20 years, crowded homes, family history, home dampness and homes at the ground floor. It was concluded that allergies to D. pteronyssinus and D. farinae contribute to allergic diseases in Zagazig City. Use of the SPT and IgE level is a promising diagnostic tool in the diagnosis of D. pteronyssinus and D. farinae.

Sensitization patterns and minimum screening panels for aeroallergens in self-reported allergic rhinitis in China

Optimization of skin prick test (SPT) panels, especially in view of significant differences in sensitizations patterns within different geographical areas, is an unmet need within China. Our aim was to assess the patterns and clinical relevance of aeroallergen sensitizations in allergic rhinitis (AR) and define the minimal battery of SPT allergens, classified according to the Köppen-Geiger climate map. Overall, 7148 subjects with self-reported AR completed a standard questionnaire and were assessed for sensitization to relevant allergens by SPT. 6340 (88.7%) patients had at least one positive skin prick reaction, and demonstrated unique sensitization patterns by stratification with age, gender, and geographic region. Sensitization to house dust mites (HDM) was highest in south China, whereas the three most prevalent aeroallergens were mugwort, ragweed and dandelion pollen in north-west China. Higher sensitization rates and multiple sensitizations were associated with AR comorbidities. Eight allergens (Der f, mugwort, Blatella, hazel, goosefoot, Penicillium notatum, animal dander and Der p) allowed identification >96% of sensitized subjects in central China. Differences in optimal panels were observed between regions, with five to six allergens being sufficient for north-east, north-west and south China. These SPT panels may provide a cost-effective tool for screening sensitized patients in China.

Air- and Dust-Borne Fungi in Indoor and Outdoor Home of Allergic Patients in a Dust-Storm-Affected Area

Despite the recent increases in fungi-induced allergic diseases, there is no report yet in the region of the Persian Gulf on concentration levels of fungi in relationship with health state. Therefore, our aim was to measure fungi prevalence as well as to evaluate the relationships between air- and dust-borne fungal genera and allergic diseases. A matched case-control study was carried out including 45 allergic cases and 45 age- and gender-matched controls for each individual. Indoor and outdoor dust and indoor air samples were collected from participant homes during May to October 2015. A Quick Take 30 Pump and sterile wet swab were used to determine fungal types and their amounts in the air (CFU/m³) and dust (CFU/100 cm²) samples, respectively. A significant reverse association was found between indoor dust-borne Alternaria and asthma (Odds ratio (OR) = 0.14, 95% CI = 0.02-0.86). Contrarily, increased levels of indoor air-borne Aspegillus fumigatus (OR = 2.00, 95% CI = 0.37-10.55) and Alternaria (OR = 3.00, 95% CI = 0.34-25.83) were correlated with asthma development. Also, correlation analysis showed a significant relation between indoor air-borne Penicillium levels and reactivity to skin prick test in asthmatic patients (p = 0.04). Our findings support the notion that fungal exposures can either cause or prevent the development of allergic diseases. Accordingly, appropriate measures should be taken for a better management of fungi-induced allergic diseases.

Report of Common Aeroallergens among Allergic Patients in Northeastern Iran

INTRODUCTION

The prevalence of atopic diseases has increased in recent decades dramatically. The most common aeroallergens in Northeastern Iran have not been fully defined. Determining the most common aeroallergens in allergic patients based on the skin prick test (SPT) was aimed in this investigation.

MATERIALS AND METHODS

This cross-sectional study enrolled 1,006 allergic patients (aged 1-86 years) from October 2010 to February 2014 referred to the Allergy clinics of Mashhad University of Medical Science. After completing a checklist including demographic information, the SPT was performed according to the patients' history of aeroallergen sensitivity.

RESULTS

Patients with symptoms of asthma, allergic rhinitis, atopic dermatitis, and urticaria were enrolled. Ninety seven percent of patients had a positive skin test to at least one aeroallergen. The most prevalent allergens were Russian thistle (Salsola kali) (50.2%), ash (Fraxinus excelsior) (36.7%), grass mix (29.1%), tree mix (21.6%), and pigweed mix (19.5%). Common allergens in patients with different symptoms of allergic disorders were as follows: asthma (Russian thistle, grass mix, ash, tree mix, and Dermatophagoides pteronyssinus); allergic rhinitis (Russian thistle, ash, grass mix, tree mix, and pigweed mix); urticaria (Russian thistle, ash, grass mix, pigweed mix, and tree mix) and atopic dermatitis (Russian thistle, grass mix, ash, tree mix, and pigweed mix). In the spring, the most prevalent allergens were Russian thistle, ash, grass mix, tree mix, and pigweed mix. In the summer, Russian thistle, ash, grass mix, tree mix, and pigweed mix accounted for the most prevalent allergens. During the autumn, Russian thistle, ash, grass mix, pigweed mix and lamb's quarter were the most common aeroallergens, while in the winter, Russian thistle, ash, grass mix, pigweed mix, and tree mix were shown to be the most common aeroallergens.

CONCLUSION

Determination of the most common aeroallergens in this area is unavoidable in the diagnosis and management of allergic disorders. Understanding the prevalence of the most common aeroallergens such as Russian thistle in 50.2% of people or other common aeroallergens can help patients and specialists to more easily identify suspected allergens, reduce costs, and support immunotherapy of allergic patients in this area. Moreover, it is helpful in avoiding pollens or cross-reactions.

Sensitization to common allergens among patients with allergies in major Iranian cities: a systematic review and meta-analysis

Various allergens are implicated in the pathogenesis of allergic diseases in different regions. This study attempted to identify the most common allergens among patients with allergies based on the results of skin prick tests in different parts of Iran. Relevant studies conducted from 2000 to 2016 were identified from the MEDLINE database. Six common groups of allergen types, including animal, cockroach, food, fungus, house dust mite, and pollen were considered. Subgroup analysis was performed to determine the prevalence of each type of allergen. The Egger test was used to assess publication bias. We included 44 studies in this meta-analysis. The overall prevalence of positive skin test results for at least one allergen was estimated to be 59% in patients with allergies in various parts of Iran. The number of patients was 11,646 (56% male and 44% female), with a mean age of 17.46±11.12 years. The most common allergen sources were pollen (47.0%), mites (35.2%), and food (15.3%). The prevalence of sensitization to food and cockroach allergens among children was greater than among adults. Pollen is the most common allergen sensitization in cities of Iran with a warm and dry climate; however, sensitization to house dust mites is predominant in northern and southern coastal areas of Iran.

Cloning and expression of Aca f 1: a new allergen of Acacia farnesiana pollen

Acacia farnesiana is the main source of allergenic pollen and one of the most important causes of respiratory allergic disease in tropical and subtropical regions of the world. The purpose of this study was to produce a recombinant variety of allergenic Ole e 1-like protein from the pollen of this tree. To predict its allergenic cross-reactivity with other members of the Ole e 1-like protein family of common allergenic plants, the nucleotide sequence homology of the Acacia Ole e 1-like protein was evaluated. Amplification of cDNA strands encoding Acacia Ole e 1-like protein was performed by polymerase chain reaction (PCR) and sequenced. Following expression in Escherichia coli using the pET-21b(+) vector, the recombinant protein was purified using metal-affinity chromatography. IgE-binding competence of purified recombinant Ole e 1- like protein (rAca f 1) was analysed by immunoassay using 25 sera collected from Acacia pollen-sensitised patients. Nucleotide sequencing revealed an open reading frame of 453 bp encoding 150 amino acid residues that belonged to the Ole e 1-like protein family, and 11 patients (44%) had considerable specific IgE levels for the rAca f 1. Immunodetection and inhibition assays indicated that the purified rAca f 1 may be the same as that in the crude extract. Aca f 1, the second allergen from Acacia pollen, was identified as a member of the family of Ole e 1-like protein. A high degree of homology was found among amino acid sequences of Aca f 1 and several allergenic members of Ole e 1-like protein family.

Particularities of allergy in the Tropics

Allergic diseases are distributed worldwide and their risk factors and triggers vary according to geographical and socioeconomic conditions. Allergies are frequent in the Tropics but aspects of their prevalence, natural history, risk factors, sensitizers and triggers are not well defined and some are expected to be different from those in temperate zone countries. The aim of this review is to investigate if allergic diseases in the Tropics have particularities that deserve special attention for research and clinical practice. Such information will help to form a better understanding of the pathogenesis, diagnosis and management of allergic diseases in the Tropics. As expected, we found particularities in the Tropics that merit further study because they strongly affect the natural history of common allergic diseases; most of them related to climate conditions that favor permanent exposure to mite allergens, helminth infections and stinging insects. In addition, we detected several unmet needs in important areas which should be investigated and solved by collaborative efforts led by the emergent research groups on allergy from tropical countries.

Cloning and Expression of Ama r 1, as a Novel Allergen of Amaranthus retroflexus Pollen

Sensitisation to Amaranthus retroflexus pollen is very common in tropical and subtropical countries. In this study we aimed to produce a recombinant allergenic Ole e 1-like protein from the pollen of this weed. To predict cross-reactivity of this allergen (Ama r 1) with other members of the Ole e 1-like protein family, the nucleotide sequence homology of the Ama r 1 was investigated. The expression of Ama r 1 in Escherichia coli was performed by using a pET-21b(+) vector. The IgE-binding potential of recombinant Ama r 1 (rAma r 1) was evaluated by immunodetection and inhibition assays using 26 patients' sera sensitised to A. retroflexus pollen. The coding sequence of the Ama r 1 cDNA indicated an open reading frame of 507 bp encoding for 168 amino acid residues which belonged to the Ole e 1-like protein family. Of the 26 serum samples, 10 (38.46%) had significant specific IgE levels for rAma r 1. Immunodetection and inhibition assays revealed that the purified rAma r 1 might be the same as that in the crude extract. Ama r 1, the second allergen from the A. retroflexus pollen, was identified as a member of the family of Ole e 1-like protein.

Lung-derived innate cytokines: new epigenetic targets of allergen-specific sublingual immunotherapy

OBJECTIVES

Sublingual allergen-specific immunotherapy is a safe and effective method for treatment of IgE-mediated respiratory allergies; however, the underlying mechanisms are not fully understood. This study was planned to test whether sublingual immunotherapy (SLIT) can exert epigenetic mechanisms through which the airway allergic responses can be extinguished.

MATERIALS AND METHODS

BALB/c mice were sensitized intraperitoneally and challenged intranasally. Then, they received sublingual treatment with recombinant Che a 2 (rChe a 2), a major allergen of Chenopodium album. After SLIT, allergen-specific antibodies in sera, cytokine profiles of spleen cell cultures, mRNA and protein expression of lung-derived IL-33, IL-25, and TSLP (thymic stromal lymphopoietin), and histone modifications of these three genes were assessed.

RESULTS

Following Immunotherapy, systemic immune responses shifted from Th2 to Th1 profile as demonstrated by significant decrease in IgE and IL-4 and substantial increase in IgG2a and IFN-γ. At local site, mRNA and protein levels of lung-derived pro-inflammatory cytokines IL-33 and TSLP were markedly down-regulated following SLIT that was associated with marked enrichment of trimethylated lysine 27 of histone H3 at promoter regions of these two cytokines.

CONCLUSION

In our study, sublingual immunotherapy with recombinant allergen effectively attenuated allergic immune responses, at least partly, by induction of distinct histone modifications at specific loci. Additionally, the lung-derived pro-allergic cytokines IL-33 and TSLP could be promising mucosal candidates for either monitoring allergic conditions or therapeutic approaches.

Identification of the main allergen sensitizers in an Iran asthmatic population by molecular diagnosis

Background

There has been a significant growth in the prevalence of allergy, mainly associated to IgE-mediated disorders such as asthma and rhinitis. The identification of atopy in asthmatic patients through the measurement of specific IgE can help to identify risk factors that cause asthmatic symptoms in patients. The development and use of individualized allergen-based tests by the Component Resolved Diagnosis has been a crucial advance in the accurate diagnosis and control of allergic patients. The objective of this work was to assess the usefulness of molecular diagnosis to identify environmental allergens as possible factors influencing the development and manifestation of asthma in a group of asthmatic patients from Iran.

Methods

Studied population: 202 adult asthmatic patients treated at the Loghman Hakim Hospital and Pasteur Institute of Teheran (Iran) from 2011 to 2012. Specific IgE determined by the ImmunoCAP system were used to both evaluate the patients’ atopic condition and the molecules involved in the allergic sensitization. SDS-PAGE IgE-immunoblotting associated with mass spectrometry was carried out to study the cockroach IgE-binding sensitizing proteins.

Results

Forty-five percent of all patients could be considered atopic individuals. Eighty-two percent of atopic patients were sensitized to pollen allergens. The Salsola kali (Sal k 1) and the Phleum pratense (rPhl p 1 and/or rPhl p 5) major allergens were the most common sensitizers among pollens (71% and 18%, respectively). Thirty-five percent of the atopic population was sensitized to cockroach. Four different allergens, including a previously unknown alpha-amylase, were identified in the cockroach extract. No significant associations could be demonstrated between the severity of asthma and the specific IgE levels in the atopic population. Statistical analysis identified the Sal k 1 as the main protein allergen influencing the development and expression of asthma in the studied population.

Conclusions

Pollen and cockroach were the most relevant allergen sources in the asthmatic population. The Salsola kali major allergen was the main cause for sensitization in the atopic patients suffering asthma. Using the Component Resolved Diagnosis, it was possible to identify a new Blattella germanica cockroach allergen (Blattella alpha amylase 53 kDa) that could sensitize a relevant percentage of this population.

Immunochemical characterization of acacia pollen allergens and evaluation of cross-reactivity pattern with the common allergenic pollens

Pollen from the Acacia has been reported as an important source of pollinosis in tropical and subtropical regions of the world. The aim of this study was to characterize the IgE binding protein of Acacia farnesiana pollen extract and evaluate cross-reactivity with the most allergenic pollens. In this study, pollen extract was fractionated by SDS-PAGE and the allergenic profile was determined by IgE-immunoblotting and specific ELISA using forty-two Acacia allergic patients. Potential cross-reactivity among Acacia and selected allergenic plants was evaluated with ELISA and immunoblotting inhibition experiments. There were several resolved protein fractions on SDS-PAGE which ranged from 12 to 85 kDa. Several allergenic protein bands with molecular weights approximately between 12 and 85 kDa were recognized by IgE-specific antibodies from Acacia allergic patients in the immunoblot assay. The inhibition by the Prosopis juliflora pollen extract was more than those by other pollen extracts. Moreover, the wheal diameters generated by the Acacia pollen extract were highly correlated with those of P. juliflora pollen extracts. The findings suggest that several proteins such as 15, 23, 45, and 50 kDa proteins could be used as diagnostic and therapeutic reagents for patients allergic to A. farnesiana and P. juliflora.