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PubMed2004

The effect of environmental tobacco smoke on eczema and allergic sensitization in children.

BACKGROUND: The negative impact of environmental tobacco smoke (ETS) on airway diseases in children is well known. Whether there is an effect on atopic eczema is not clear. OBJECTIVES: To determine the impact of ETS on atopic eczema, allergic sensitization and allergic airway diseases in 1669 school beginners. METHODS: The prevalence of atopy-related health outcomes was assessed by questionnaire, dermatological examination, skin prick testing and specific immunoglobulin E measurement. Exposure assessments were based on measurement of cotinine [expressed as cotinine to creatine ratio (CCR)] in spot urine samples (n = 1220) together with questionnaire and interview data on smoking behaviour of the parents. RESULTS: In the total study group, prevalence of atopic eczema diagnosed on examination was significantly associated with urinary CCR values. The odds ratio (OR) and 95% confidence interval (CI), calculated for an increase of 100 ng mg-1 CCR was 1.97 (95% CI 1.23-3.16). The prevalence of skin manifestations according to questionnaire data as well as a history of asthma, wheezing, and hay fever were positively although not significantly associated with ETS exposure. When genetically predisposed children (defined by the presence of parental atopy) were compared with children whose parents had no atopy, the ORs of allergic outcome variables were generally higher in the first group. In the group of predisposed children, significant associations with urinary CCR were found for allergic sensitization against house dust mites as measured by skin prick test (OR 3.10, 95% CI 1.63-5.90). CONCLUSIONS: Children are at a higher risk of developing an atopic eczema when exposed to ETS and genetically predisposed children are at higher risk of developing a sensitization against house dust mites.

Child↗

PubMed2003

Does exposure to dogs and cats in the first year of life influence the development of allergic sensitization?

PURPOSE OF REVIEW: The goal of the review is to place studies published after 1 June 2002, concerning the relationship between early life exposure to cats and dogs and the later development of allergy, within the context of the effects of other environmental exposures on allergic disease. RECENT FINDINGS: Most of the recent studies have shown that exposure to cats and dogs early in infancy reduces the prevalence of allergic sensitization or allergic disease later in childhood. While this general trend is relatively consistent, there are differences in specific findings between studies, such as the effect of parental allergies. Other studies suggest that the association between cat and dog exposure and a lower risk of allergy is due to either differences in other environmental exposures or to genetic differences between exposed and non-exposed children. It is impossible to directly compare the results from all of these studies since there are often important differences in racial/ethnic backgrounds of the children, climate, housing conditions, and the family and social customs of those enrolled in different studies. SUMMARY: The risk of a child developing any form of allergy appears to depend upon many factors including a child's genetic constitution, early environmental exposure to allergens and to other agents which interact with the immune system, and to allergen exposure later in life. It appears that exposure to something that is increased in homes with cats or dogs reduces the risk of allergic sensitization.

Allergy and Immunology↗

PubMed2005

Effects of early intake of fruit or vegetables in relation to later asthma and allergic sensitization in school-age children.

AIM: To assess the associations between nutrition supplements in infancy and later asthma and allergy in school-age children, and to explore the impact of environmental factors in early life. METHODS: Five hundred and two children underwent clinical examination, skin prick test and a second parentally completed questionnaire within 2 y of a cross-sectional questionnairebased study, including 4585 primary school children (6-16 y old) in 1994 from urban Oslo (37%), the mountainous area of Hallingdal (42%), and the industrial, coastal area of Odda (21%). The children were selected from the 1994 survey on the basis of reported diagnosed asthma (n=166), wheeze in the last 12 mo (n=155) and no asthma/no wheeze (n=181). Questions were related to nutrition and environmental exposure in early life. Possible associations between allergic sensitization or asthma at school age and exposures were estimated by logistic regression analysis, adjusting for potential confounders. RESULTS: Daily intake of fresh fruit or vegetables, but not extra vitamins or cod liver oil supplements, in infancy decreased the risk of asthma (adjusted odds ratio (aOR) 0.57 (95% confidence interval (CI): 0.37-0.88). Early supplements of cod liver oil and extra vitamins were associated with increased allergic sensitization (aOR 1.78 (95% CI: 1.03-3.07) and 1.71 (95% CI: 1.01-2.88), respectively). A significantly higher prevalence of allergic sensitization was found in children living in Hallingdal compared to Odda, while the latter children, on the other hand, had the highest prevalence of house dust mite allergy (p = 0.001 vs Hallingdal and p = 0.04 vs Oslo). CONCLUSION: The present study suggests that the early introduction of daily fresh fruit or vegetables may decrease the risk of asthma after 1 y of life, whereas allergic sensitization at school age seemed to increase with extra vitamin and cod liver oil supplements during infancy. Living area influenced allergic sensitization, with differences between coastal and inland areas.

Adolescent↗

PubMed2006

Rabbit allergens: a significant risk for allergic sensitization in subjects without occupational exposure.

BACKGROUND: Although rabbits are becoming popular as pets, data about the characteristics of allergic sensitization to rabbit allergens in patients without professional exposure are scarce. AIMS OF THE STUDY: To determine the characteristics of allergic sensitization to pet rabbits, and the role of direct and indirect exposure to rabbits and rabbit allergens in non-professionally exposed patients. METHODS: From among 1124 consecutive outpatients, we selected all subjects with an immediate skin reaction to rabbit dander. A clinical history including a careful evaluation of the modality of rabbit exposure, the results of skin-prick tests (SPTs) and total/specific IgE antibodies were recorded. The prevalence of rabbit ownership in the Naples area was also calculated. RESULTS: Among 753 SPT-positive patients, 20 (2.65%) were sensitized to rabbit dander (5 patients were mono-sensitized). Fifteen patients reported direct rabbit contact (7 were rabbit owners and 8 had occasional contact outside the home); 3 patients had indirect exposure through contact with rabbit owners and 2 patients denied any direct or indirect exposure. Rabbit mono-sensitized owners of pet rabbits had persistent (moderate-severe) symptoms. The prevalence of rabbit ownership is 1.56%. CONCLUSIONS: In susceptible not professionally exposed individuals, direct rabbit contact and, in some cases, indirect or no apparent exposure, may induce allergic sensitization to rabbit allergens. A progressive increase in rabbit sensitization (also by indirect exposure) may be expected as a consequence of the increase in rabbit ownership.

Adolescent↗

PubMed1999

Bronchial allergen challenge in subjects with low levels of allergic sensitization to indoor allergens.

BACKGROUND: Low skin reactivity to common inhalant allergens is frequently found in asymptomatic individuals as well as in patients with respiratory complaints. However, most studies on bronchial allergen challenge concern patients with high levels of allergic sensitization. The present study was directed to bronchial reactions after allergen challenge in subjects with low skin reactivity to Dermatophagoides pteronyssinus or cat dander. METHODS: Titrated intracutaneous skin tests, skin prick tests, specific IgE assays, histamine release on washed leukocytes, and bronchial histamine and allergen-challenge tests were performed in 20 subjects with an intracutaneous skin test threshold for cat dander (Felis domesticus) or D. pteronyssinus above 0.1 BU/ml (mean wheal diameter in skin prick test with 10000 BU/ml: 4.4mm). Ten of the 20 patients had specific IgE below the detection limit in at least one of the three IgE assays which were done. Fifteen patients had a specific IgE level below 2 kU/I in all three tests. As a positive control group, the same parameters were studied in seven moderately sensitized patients with an intracutaneous skin test threshold below 0.1 BU/ml (mean wheal diameter with 10000 BU/ml: 7.2mm). RESULTS: The 20 subjects with low levels of allergic sensitization had an early decrease in FEV1 of 8.6% (P<0.01) and a mean late decrease of 6.3% (P<0.05). There was a trend for decrease in PC20 histamine 24h after allergen challenge (-0.4 doubling doses, P=0.09). CONCLUSIONS: In this group of subjects with low levels of allergic sensitization, a statistically significant early and late decrease in FEV1 was found. However, the decrease in lung function was small and unnoticed by most patients. The increase in nonspecific bronchial hyperresponsiveness after bronchial allergen challenge did not reach statistical significance in the study group. The results indicate that allergen exposure in patients with low levels of allergic sensitization may lead to airways changes in the absence of acute symptoms.

Adult↗

PubMed2003

Association of alcohol consumption with total serum immunoglobulin E levels and allergic sensitization in an adult population-based survey.

BACKGROUND: Chronic alcoholism is associated with increased total serum IgE levels. OBJECTIVE: The study aimed to investigate the relationship between alcohol intake and both total serum IgE levels and allergic sensitization in a general adult population. MATERIALS AND METHODS: A total of 720 subjects was randomly selected (stratified by age) from the population older than 18 years of A-Estrada (Spain) and invited to participate in the study. From 697 eligible subjects, 469 (67%, median age 54 years, range 18 to 92 years, 44% males, 75% of cases from a rural environment) agreed to participate. A battery of 13 skin prick tests to common aeroallergens was performed in all subjects. Cases with at least one positive test (n = 121, 26%) were considered to have allergic sensitization. The most frequent sensitisers were mites and pollens (24% and 10% of subjects, respectively). Total serum IgE was measured in 465 subjects (99%). Alcohol consumption was registered as the number of standard (approximately 10 g) drinking units habitually consumed per week. A total of 244 subjects (52%) were alcohol consumers (median intake, 14 units/week, range 1 to 147 units/week). Abstainers (n = 225, 48%) constituted the reference category. RESULTS: Alcohol consumption of more than 14 units/week was associated with an increase in serum IgE levels after adjusting for age, gender, allergic sensitization and smoking (P = 0.02). Alcohol consumption was not significantly associated with either overall allergic sensitization or mite sensitization after adjusting for age, gender and smoking. However, alcohol consumption of more than 14 units/week was associated with an increased prevalence of pollen sensitization (adjusted OR 3.15, 95% CI 1.19 to 8.34, P = 0.02). CONCLUSION: Alcohol consumption above a certain threshold is associated with an increase in total serum IgE levels. Alcohol consumption may also be associated with an increased prevalence of pollen sensitization.

Adolescent↗

PubMed2002

Non-allergenic antigen in allergic sensitization: responses to the mite ferritin heavy chain antigen by allergic and non-allergic subjects.

BACKGROUND: The majority of house dust mite proteins are non-allergenic. There is, however, no information on the type of immune responses produced to these proteins and if the responses are affected by allergic sensitization. OBJECTIVE: To identify and produce a non-allergenic antigen of the house dust mite and compare antibody and T cell responses with the responses to allergens in sensitized and non-sensitized individuals. RESULTS: Ferritin heavy chain was cloned from a cDNA library as a candidate non-allergen of the house dust mite. It bound IgG but not IgE in the sera of allergic and non-allergic subjects and induced high T cell proliferative responses that correlated highly with the responses to the major allergen Der p 2. The cytokine response to the non-allergen was characterized by the release of high levels of both Th1 and Th2 cytokines from the PBMC of both allergic and non-allergic subjects. In contrast, the response to Der p 2 showed the expected high level of Th2 cytokine release from the PBMC of allergic subjects, while the Th2 cytokine production from PBMC of non-allergic subjects was low and even lower than that induced by ferritin heavy chain. The levels of IFN-gamma release were similar for all groups. Der p 2 induced significantly more IL-10 than ferritin in the non-allergic group. CONCLUSION: The T cell responses to a non-allergenic protein of the house dust mite were high and strongly correlated with the response to the major allergen. The non-allergenic protein induced high levels of Th1 and Th2 cytokine in both allergic and non-allergic subjects, while the allergen induced high levels of Th2 cytokine in allergic subjects and low levels in non-allergic subjects. The responses to the allergen were thus independently up- and down-regulated with no evidence of bystander regulation.

Adult↗

PubMed2003

Relationships of allergic sensitization, total immunoglobulin E and blood eosinophils to asthma severity in children of the EGEA Study.

BACKGROUND: Although allergy is highly associated with childhood asthma, it is not well known if there is a relationship between the intensity of allergic sensitization and asthma severity. OBJECTIVE: The objectives of the study were to examine the relationships between several markers of allergy and asthma severity in asthmatic children included in the Epidemiological study on the Genetics and Environment of Asthma, bronchial hyper-responsiveness and atopy (EGEA). METHODS: The population comprised 216 asthmatic children below 16 years of age. Total IgE and blood eosinophil counts were measured and skin prick tests to 11 aeroallergens were performed. The intensity of the allergic sensitization was assessed by the number of positive skin prick tests and by skin weal sizes. Asthma severity was measured with four criteria: a clinical severity score, history of hospitalization for asthma, FEV1% predicted and inhaled steroid use in the last 12 months. RESULTS: Most of the children were sensitized to at least one aeroallergen (88.2%). Atopy was not related to the severity of asthma, except for a tendency for a more severe clinical score in non-atopic children. The type and intensity of the allergic sensitization were not associated with any criteria of asthma severity. Total IgE was significantly increased in children treated with inhaled corticosteroids and in children ever hospitalized for asthma (P-values 0.009 and 0.04, respectively). Eosinophil counts were not related to asthma severity. CONCLUSION: Our results suggest that severe childhood asthma may be related to a high level of total IgE but not to blood eosinophil counts. The lack of positive relationships between both atopy and the intensity of allergic sensitization with asthma severity supports the hypothesis of different risk factors being associated with asthma and with the severity of asthma.

Adolescent↗

PubMed2003

Parental allergic status influences the risk of developing allergic sensitization and an asthmatic-like phenotype in canine offspring.

Increasing evidence suggests that parental allergic status, especially that of the mother, may play a unique and important role in influencing the development of fetal infant immune responses to inhaled allergens, independently of genetic predisposition. We have developed an experimental model in dogs where the offspring from allergic parents, when exposed to inhaled allergen, develop allergic sensitization and an asthmatic phenotype, whereas the offspring from non-allergic parents do not. Offspring from ragweed-sensitized (two litters, n = 10) or non-sensitized (two litters, n = 11) Beagle dogs were exposed repeatedly, by inhalation, to ragweed or filtered air (negative control) beginning within 1 week after birth. Serum levels of total immunoglobulin (Ig)E, and ragweed-specific IgE and IgG, were measured at specific time-points up to 40 weeks after birth. Cell differentials in the bronchoalveolar lavage were determined on days 1 and 4 following ragweed instillation into the offspring's lungs at 26 weeks of age. Changes in pulmonary resistance following challenge with histamine and ragweed (five breaths) were measured at 40 weeks after birth. Offspring from sensitized parents exposed to ragweed developed elevated serum total IgE and ragweed-specific IgE and IgG, and showed an increased pulmonary resistance to histamine and ragweed, and increased numbers of eosinophils in bronchoalveolar lavage. In contrast, offspring from non-sensitized parents did not exhibit this immune response. These results suggest that parental allergic sensitivity is important in the development of allergic sensitization and an asthmatic phenotype in the offspring.

Administration, Inhalation↗

PubMed2006

Asthma during the primary school ages--prevalence, remission and the impact of allergic sensitization.

BACKGROUND: Childhood is the most important time for asthma development. The aims of this study were to study changes in prevalence of asthma and wheeze, remission of asthma and changes in risk factor pattern from age 7-8 to age 11-12 in a cohort of school children. METHODS: In 1996, 3525 children aged 7-8 years in northern Sweden were invited to participate in a parental expanded ISAAC questionnaire survey. The cohort has been followed prospectively with yearly follow-ups to age 11-12, with a 97% yearly response rate. Skin prick tests were conducted at age 7-8 and 11-12. RESULTS: The prevalence of physician-diagnosed asthma increased from 5.7% at age 7-8 to 7.7% at age 11-12. Life-time prevalence of wheeze was 34.7% at age 11-12. The remission of asthma was 10% yearly and inversely related to allergic sensitization. Relapses were common, and remission persisting throughout the observation period was 5% yearly. Allergic sensitization was associated with current asthma at age 7-8 [adjusted odds ratio (OR) 4.9 (95% confidence interval (CI) 3.3-7.3)] and when the children were 4 years older [OR 5.6 (3.9-8.2)]. A family history of asthma was associated with current asthma at age 7-8 [OR 3.0 (2.1-4.5)] and 11-12 (OR 2.8 [2.0-3.9]). Ever having lived with a cat was significantly negatively associated with current asthma. CONCLUSIONS: The prevalence of asthma increased continuously during the primary school ages. Among several significant risk factors, allergic sensitization and a family history of asthma were the most important. With increasing age many known risk factors lost significance. Remission was inversely related to allergic sensitization.

Age Distribution↗

PubMed1990

Allergic sensitization in elderly patients with chronic obstructive pulmonary disease.

To study whether allergic sensitization occurs in elderly patients with chronic pulmonary obstructive disease (COPD), we examined serum IgE and skin test reactivity to allergens in three age-matched groups of normal subjects, and in patients with COPD and bronchial asthma (BA). Serum IgE was significantly higher in patients with COPD and BA than in normal subjects (p less than 0.05), and patients with COPD showed serum IgE levels as high as those of patients with BA. However, the skin test scores were significantly higher in patients with BA than in normal subjects and patients with COPD (p less than 0.05). Neither serum IgE nor skin test score significantly correlated with FEV1%, PaO2, PaCO2 or Brinkman's Index in any group (p greater than 0.20). These results suggest that allergic sensitization occurs in elderly patients with COPD and that symptoms associated with COPD may be partly due to allergic inflammation.

Asthma↗

PubMed2006

Domestic allergen and endotoxin exposure and allergic sensitization in Cyprus.

We investigated the relationship between domestic allergen and endotoxin exposure and allergic sensitization among children in Cyprus. We skin prick tested 128 children aged 15-16 yr (random samples of 85 children with self-reported asthma and 43 healthy controls) and measured their domestic exposure to endotoxin and allergens (mite, cat, and dog). We analyzed the data using multivariate logistic regression (adjusting for gender, area of residence and parental history) and presented the outcomes as odds ratios (OR) and 95% confidence intervals (CI). Among this selected population, 19% of children were sensitized to mite, 15% to cat and 7% to dog. Male gender (OR 2.74, 95% CI 1.18-6.38, p = 0.02), maternal history of allergic disease (OR 3.53, 95% CI 1.13-11.00, p = 0.03), increasing endotoxin (OR 1.58, 95% CI 1.00-2.49, p = 0.05) and residence in the district of Nicosia (OR 2.48, 95% CI 1.01-6.08, p = 0.05) were independent associates of allergic sensitization. Factors associated with mite sensitization were increasing Der p 1 and endotoxin exposure (OR 1.28, 95% CI 1.01-1.62, p = 0.04 and OR 1.76, 95% CI 1.01-3.08, p = 0.05, respectively) and living in an urban area (OR 6.80, 95% CI 1.37-33.67, p = 0.02). Sensitization to domestic pets was associated only with paternal allergic disease (cat: OR 5.68, 95% CI 1.57-23.56, p = 0.02; dog: OR 13.5, 95% CI 1.79-101.73, p = 0.01), but not with pet ownership or specific allergen or endotoxin exposure. In conclusion, mite allergen exposure was associated with sensitization to mite, but there was no association between cat and dog allergen exposure and specific sensitizations. Surprisingly, in this area, increasing endotoxin exposure was associated with an increased risk of sensitization.

Adolescent↗

PubMed1979

Contact allergic sensitivity to plants and the photosensitivity dermatitis and actinic reticuloid syndrome.

Contact allergic sensitivity to oleoresin extracts from Compositae plants was found to be usually present in individuals suffering from the photosensitivity dermatitis and actinic reticuloid syndrome. It was demonstrated in forty-seven out of fifty-five examples of this syndrome. These results provide support for the view that contact allergic sensitivity is an important aspect of the state of chronic photosensitivity in the middle-aged and elderly male.

Adult↗

PubMed2001

School education and allergic sensitization in adults.

BACKGROUND: There is evidence of an association between socioeconomic status (SES) and atopy mainly from studies in children which investigated atopic diseases and parental SES. We determined the association of allergic sensitization, as measured by skin prick test (SPT) and allergen-specific IgE (RAST), and SES in a population-based study in adults. METHODS: Within a population-based, nested, case-control study, a standardized interview was performed and allergic sensitization to common aeroallergens was determined by SPT and RAST. RESULTS: A total of 1537 adults (50.4% female, age: median 50.0, range 28-78 years) were investigated, half of whom (50.2%) exhibited at least one positive RAST result according to the study design. SPT reactivity was 37.3% in this group and was estimated to be 26.1% in the representative study base of 4178 adults. Within increasing categories of school graduation (none; after 8, 10, 13, and >13 years), the prevalence of SPT (20.5%, 31.3%, 44.0%, 44.2%, 48.1%; P trend <0.0001) and RAST reactivity (35.0%, 48.0%, 52.3%, 48.4%, 58.4%; P trend=0.004) increased continuously. Similar results were obtained when testing this association on the level of single allergens. After control for age, sex, and parental history of atopic diseases, all but the first odds ratios for SPT remained significant (first category=reference, 2.06, 3.21, 3.88, 3.96). The same model for RAST reactivity revealed a similar result with effect estimate for the last category being significant (first category=reference, 1.89, 2.08, 2.10, 2.81). CONCLUSIONS: Allergic sensitization (SPT and RAST) to common aeroallergens in adults follows a significant and linear association with school education.

Adult↗

PubMed2001

Factors related to allergic sensitization to aeroallergens in a cross-sectional study in adults: The Copenhagen Allergy Study.

BACKGROUND: The factors underlying recent increases in the prevalence of respiratory allergy are largely unknown. OBJECTIVE: To assess the association between allergic sensitization and several lifestyle/environmental factors. METHODS: A cross-sectional population-based study of 15-69-year-olds in Copenhagen was carried out in 1990. The participation rate was 77.5% (1112/1435). Different lifestyle/environmental factors (explanatory variables) were defined based on questionnaire data. Dependent (outcome) variables were skin prick test (SPT) positivity or specific IgE positivity to common aeroallergens. Explanatory variables associated with outcome in univariate analysis (P < 0.25) were selected for multivariate analysis. Subsequently, a final model for each dependent variable was obtained by stepwise regression analysis (cut-off for entry/removal of variables: P < 0.1). RESULTS: Male sex, young age, low number of siblings, a positive family history of hay fever and never smoking, were independently associated with both SPT positivity and specific IgE positivity. Furthermore, SPT positivity was positively associated with alcohol consumption (dose-response relationship only), and negatively associated with previous keeping of a dog in the household. The association between alcohol consumption and SPT positivity was mainly due to the consumption of wine and remained after adjustment for educational level. Specific IgE positivity was furthermore associated with body mass index with no apparent dose-response relationship. CONCLUSION: Being male, young age, a positive family history of hayfever, low number of siblings and never smoking, were independently associated with allergic sensitization. In addition, the results indicated a possible relationship of alcohol consumption, body mass index and previous keeping of a dog in the household to allergic sensitization. There is a need for prospective studies of risk factors for respiratory allergy.

Adolescent↗

PubMed2005

Wheeze, allergic sensitization and geohelminth infection in Butajira, Ethiopia.

BACKGROUND: The effect of geohelminth infection on wheeze and allergen sensitization is inconsistent across different epidemiological studies. OBJECTIVE: To investigate the association between self-reported wheeze, self-reported asthma, allergic sensitization and geohelminth infection in urban and rural areas of Butajira, southern Ethiopia. METHODS: Questionnaire data on wheeze, asthma and a range of confounding variables was gathered in a cross-sectional study of 7649 people aged 5 years or more from the Butajira Rural Health Project database. Allergic skin sensitization to Dermatophagoides pteronyssinus and cockroach was measured, and a stool sample collected for qualitative and quantitative geohelminth analysis. RESULTS: Wheeze was weakly associated with allergic sensitization to D. pteronyssinus and cockroach (odds ratios (OR) 1.21, 95% confidence interval (CI) 0.98-1.51, and 1.27, 95% CI 1.00-1.62, respectively). Self-reported asthma was related to sensitization to D. pteronyssinus only (OR 4.09, 95% CI 2.86-5.84). Geohelminths were present in 33.8% of participants, and the median egg load in infested individuals was 6 eggs/g. Overall, presence of any geohelminths was associated with a diminished risk of cockroach sensitization (adjusted OR 0.82, 95% CI 0.68-0.99) but there were no significant protective effects of any geohelminth infection against wheeze or asthma. CONCLUSION: In a developing country community with relatively low geohelminth prevalence and intensity, we found weak association between allergic sensitization and wheeze, but no evidence of a protective effect of geohelminths against wheeze or asthma.

Adolescent↗

PubMed2006

Cigarette smoke exposure facilitates allergic sensitization in mice.

BACKGROUND: Active and passive smoking are considered as risk factors for asthma development. The mechanisms involved are currently unexplained. OBJECTIVE: The aim of this study was to determine if cigarette smoke exposure could facilitate primary allergic sensitization. METHODS: BALB/c mice were exposed to aerosolized ovalbumin (OVA) combined with air or tobacco smoke (4 exposures/day) daily for three weeks. Serology, lung cytopathology, cytokine profiles in bronchoalveolar lavage fluid (BALF) and on mediastinal lymph node cultures as well as lung function tests were performed after the last exposure. The natural history and the immune memory of allergic sensitization were studied with in vivo recall experiments. RESULTS: Exposure to OVA induced a small increase in OVA-specific serum IgE as compared with exposure to PBS (P < 0.05), while no inflammatory reaction was observed in the airways. Exposure to cigarette smoke did not induce IgE, but was characterized by a small but significant neutrophilic inflammatory reaction. Combining OVA with cigarette smoke not only induced a significant increase in OVA-specific IgE but also a distinct eosinophil and goblet cell enriched airway inflammation albeit that airway hyperresponsiveness was not evidenced. FACS analysis showed in these mice increases in dendritic cells (DC) and CD4+ T-lymphocytes along with a marked increase in IL-5 measured in the supernatant of lymph node cell cultures. Immune memory experiments evidenced the transient nature of these phenomena. CONCLUSION: In this study we show that mainstream cigarette smoke temporary disrupts the normal lung homeostatic tolerance to innocuous inhaled allergens, thereby inducing primary allergic sensitization. This is characterized not only by the development of persistent IgE, but also by the emergence of an eosinophil rich pulmonary inflammatory reaction.

Allergens↗

PubMed2000

Exposure and allergic sensitization to cockroach allergen in East Germany.

BACKGROUND: Some studies suggest that the prevalence of sensitization to cockroach allergens may be higher in the United States than in Europe, but there are no comparable data from population-based studies. OBJECTIVES: To determine the prevalence of allergic sensitization to German cockroach (GCR) in German schoolchildren and to assess its clinical relevance; and to determine the exposure to the major GCR allergen Bla g 2 in non-selected homes and nurseries. METHODS: The prevalence of allergic sensitization to GCR and other allergens was determined by measurement of specific IgE and skin-prick tests in a cross-sectional study of 2993 children aged 5-11 years in Dresden, Germany. The prevalence of atopic disease was determined by questionnaire, and pulmonary function and bronchial hyperresponsiveness to hypertonic saline were measured. Bla g 2 exposure was determined on floors of 187 kitchens and 47 nurseries by a commercial sandwich ELISA. RESULTS: One hundred and twenty-seven (4.2%) of the children had specific IgE (> 0.7 kU/L) against GCR. Among children with current wheeze, 8.4% were GCR-sensitized. Compared to data from the United States, the prevalence of sensitization to cockroach was similar in children without asthma (3.9%), but less frequent in asthmatic children from Dresden (6.1%). After adjustment for positive reactions to other allergens (SX1 test) no significant impact of GCR sensitization on wheeze or other symptoms and diagnoses was found. Bla g 2 was detected in 29% of the kitchens and 43% of the nurseries. None of these sites had exposure levels above the proposed threshold for causing disease of 80 ng/g dust. CONCLUSION: The data suggest that allergic sensitization to GCR is less frequent in asthmatics from Dresden, Germany than in US cities. The data indicate that GCR sensitization is not an independent risk factor for asthma and other atopic diseases in 5-11-year-olds from this city.

Allergens↗