A novel maternal diet index (MDI), characterizing offspring asthma- and allergy-associated maternal intake during pregnancy was constructed and validated in Healthy Start, USA. This study aims to (1) externally validate the asthma findings from Healthy Start in the NorthPop Birth Cohort Study (NorthPop) in Sweden; and (2) characterize the diet and demographics of the two cohorts. The MDI was computed as a weighted combination of seven components associated with offspring allergies and asthma, including vegetables and yogurt (associated with decreased odds) and cold cereals, fried potatoes, juice, red meat, and rice (associated with increased odds). Doctor diagnoses provided childhood asthma incidence and timing. Parametric Weibull time-to-event analysis evaluated associations between the MDI, dichotomized at the median (72.2) for Healthy Start, and offspring asthma. The NorthPop and Healthy Start mean MDI values differed significantly (p < 0.001) and in NorthPop, only 6.1% had MDI < 72.2. Data from 6446 mother-child dyads in NorthPop yielded a crude hazard ratio (HR) for asthma of 0.70 (95% confidence interval [CI] 0.50-0.98, p = 0.037) and a fully adjusted HR of 0.84 (0.55-1.29; p = 0.428) for MDI > 72.2 versus < 72.2 (n = 4655). The fully adjusted HR for 945 Healthy Start dyads was significant at HR 0.41 (0.29-0.57; p < 0.0001). Results show that in a population with different maternal dietary patterns and demographics compared to the source population, MDI > 72.2 was not an independent predictor of offspring asthma. Further proof of the utility and generalizability of the MDI needs to be tested in other populations.
Wilson JM, Keshavarz B, Retterer M, Workman LJ, Schuyler AJ, et al.
The Journal of allergy and clinical immunology •
A syndrome of mammalian meat allergy relating to IgE specific for galactose-α-1,3-galactose (α-Gal) was first reported 10 years ago in the southeastern United States and has been related to bites of the lone star tick (Amblyomma americanum). Here we investigated the epidemiology of the "α-Gal syndrome" in the United States and sought additional evidence for the connection to tick bites. A survey of allergists was conducted by using a snowball approach. A second tier of the survey included questions about anaphylaxis to imported fire ants (IFAs). History of tick bites and tick-related febrile illness were assessed as part of a case-control study in Virginia. Antibody assays were conducted on sera from subjects reporting allergic reactions to mammalian meat or IFA. In North America the α-Gal syndrome is recognized across the Southeast, Midwest, and Atlantic Coast, with many providers in this area managing more than 100 patients each. The distribution of cases generally conformed to the reported range of A americanum, although within this range there was an inverse relationship between α-Gal cases and cases of IFA anaphylaxis that were closely related to the territory of IFA. The connection between tick bites and α-Gal sensitization was further supported by patients' responses to a questionnaire and the results of serologic tests. The α-Gal syndrome is commonly acquired in adulthood as a consequence of tick bites and has a regional distribution that largely conforms to the territory of the lone star tick. The epidemiology of the syndrome is expected to be dynamic and shifting north because of climate change and ecologic competition from IFA.
Wilson JM, Keshavarz B, James HR, Retterer MKC, Schuyler AJ, et al.
The Journal of allergy and clinical immunology •
IgE to α-Gal is a cause of mammalian meat allergy and has been linked to tick bites in North America, Australia, and Eurasia. Reports from the developing world indicate that α-Gal sensitization is prevalent but has been little investigated. We sought evidence for the cause(s) of α-Gal sensitization and lack of reported meat allergy among children in less developed settings in Ecuador and Kenya. IgE to α-Gal and total IgE were assessed in children from Ecuador (n = 599) and Kenya (n = 254) and compared with children with (n = 42) and without known (n = 63) mammalian meat allergy from the southeastern United States. Information on diet, potential risk factors, and helminth infections was available for children from Ecuador. IgG to α-Gal and antibodies to regionally representative parasites were assessed in a subset of children. In Ecuador (32%) and Kenya (54%), α-Gal specific IgE was prevalent, but levels were lower than in children with meat allergy from the United States. Sensitization was associated with rural living, antibody markers of Ascaris exposure, and total IgE, but not active infections with Ascaris or Trichuris species. In Ecuador, 87.5% reported consuming beef at least once per week, including 83.9% of those who had α-Gal specific IgE. Levels of α-Gal specific IgG were not high in Ecuador, but were greater than in children from the United States. These results suggest that in areas of the developing world with endemic parasitism, α-Gal sensitization is (1) common, (2) associated with Ascaris exposure, and (3) distinguished by a low percentage of specific/total IgE compared with individuals with meat allergy in the United States.
We aimed to explore the roles of glycoproteins in the pathogenesis of chronic and latent Keshan disease (CKD and LKD), and screen the lectins as indicators of significant differences in glycoproteins of KD saliva and serum. Blood and saliva were collected from 50 CKD, 50 LKD patients and 54 normal individuals. Saliva and serum lectin microarrays and saliva and serum microarrays were used to screen and verify the differences in the levels of lectin among the three groups. In the male saliva lectin microarray, (potato) lectin (STL) and other 9 lectins showed differences between CKD and normal; STL and other 9 lectins showed differences between LKD and normal; (AAL) and other 15 lectins showed differences between CKD and LKD. In the female saliva microarray, (GSL-I) and other 9 lectins showed differences between CKD and normal; STL and other 7 lectins showed differences between LKD and normal; (MAL-I) and (WGA) showed difference between CKD and LKD. In the male serum lectin microarray, (PTL-I) and other 16 lectins showed differences between CKD and normal; Ulexeuropaeus agglutinin I (UEA-I) and other 9 lectins showed differences between LKD and normal; AAL and other 13 lectins showed differences between CKD and LKD. In the female serum lectin microarray, WGA and other 13 lectins showed differences between CKD and normal; (EEL) and other 6 lectins showed differences between LKD and normal; MAL-I and other 14 lectins showed differences between CKD and LKD. Carbohydrate chain GlcNAc and α-Gal may play crucial roles in the pathogenesis of KD. STL may be considered the diagnostic biomarker for male CKD and LKD, while WGA may be useful in distinguishing between the two stages. STL may be considered the diagnostic biomarker for female LKD.
Konradsen JR, Fujisawa T, van Hage M, Hedlin G, Hilger C, et al.
The Journal of allergy and clinical immunology •
The prevalence of allergy to furry animals has been increasing, and allergy to cats, dogs, or both is considered a major risk factor for the development of asthma and rhinitis. An important step forward in the diagnosis of allergy to furry animals has been made with the introduction of molecular-based allergy diagnostics. A workshop on furry animals was convened to provide an up-to-date assessment of our understanding of (1) the exposure and immune response to the major mammalian allergens, (2) the relationship of these responses (particularly those to specific proteins or components) to symptoms, and (3) the relevance of these specific antibody responses to current or future investigation of patients presenting with allergic diseases. In this review research results discussed at the workshop are presented, including the effect of concomitant exposures from other allergens or microorganisms, the significance of the community prevalence of furry animals, molecular-based allergy diagnostics, and a detailed discussion of cat and dog components.
Commins SP, Kelly LA, Rönmark E, James HR, Pochan SL, et al.
American journal of respiratory and critical care medicine •
IgE antibodies to the mammalian oligosaccharide galactose-α-1,3-galactose (α-gal) are common in the southeastern United States. These antibodies, which are induced by ectoparasitic ticks, can give rise to positive skin tests or serum assays with cat extract. To evaluate the relationship between IgE antibodies to α-gal and asthma, and compare this with the relationship between asthma and IgE antibodies to Fel d 1 and other protein allergens. Patients being investigated for recurrent anaphylaxis, angioedema, or acute urticaria underwent spirometry, exhaled nitric oxide, questionnaires, and serum IgE antibody assays. The results were compared with control subjects and cohorts from the emergency department in Virginia (n = 130), northern Sweden (n = 963), and rural Kenya (n = 131). Patients in Virginia with high-titer IgE antibodies to α-gal had normal lung function, low levels of exhaled nitric oxide, and low prevalence of asthma symptoms. Among patients in the emergency department and children in Kenya, there was no association between IgE antibodies to α-gal and asthma (odds ratios, 1.04 and 0.75, respectively). In Sweden, IgE antibodies to cat were closely correlated with IgE antibodies to Fel d 1 (r = 0.83) and to asthma (P < 0.001). These results provide a model of an ectoparasite-induced specific IgE response that can increase total serum IgE without creating a risk for asthma, and further evidence that the main allergens that are causally related to asthma are those that are inhaled.
Commins SP, James HR, Kelly LA, Pochan SL, Workman LJ, et al.
The Journal of allergy and clinical immunology •
In 2009, we reported a novel form of delayed anaphylaxis to red meat that is related to serum IgE antibodies to the oligosaccharide galactose-α-1,3-galactose (alpha-gal). Most of these patients had tolerated meat for many years previously. The implication is that some exposure in adult life had stimulated the production of these IgE antibodies. We sought to investigate possible causes of this IgE antibody response, focusing on evidence related to tick bites, which are common in the region where these reactions occur. Serum assays were carried out with biotinylated proteins and extracts bound to a streptavidin ImmunoCAP. Prospective studies on IgE antibodies in 3 subjects after tick bites showed an increase in levels of IgE to alpha-gal of 20-fold or greater. Other evidence included (1) a strong correlation between histories of tick bites and levels of IgE to alpha-gal (χ(2) = 26.8, P < .001), (2) evidence that these IgE antibodies are common in areas where the tick Amblyomma americanum is common, and (3) a significant correlation between IgE antibodies to alpha-gal and IgE antibodies to proteins derived from A americanum (r(s) = 0.75, P < .001). The results presented here provide evidence that tick bites are a cause, possibly the only cause, of IgE specific for alpha-gal in this area of the United States. Both the number of subjects becoming sensitized and the titer of IgE antibodies to alpha-gal are striking. Here we report the first example of a response to an ectoparasite giving rise to an important form of food allergy.