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Notes: Carpet and floor dust samples were collected in four different seasons, from 39 Swedish homes of babies with a family history of allergy. House-dust mite (Der p 1, Der f 1) and cat (Fel d 1) allergen contents were determined by mab ELISA, and the levels were related to various environmental factors. Both mite and cat antigens were detected in 94% of the samples and in all homes, but the levels were low (Der p 1, range 15 ng–1944 ng/g fine dust; Der f 1, range 14 ng–264 ng/g of fine dust; Fel d 1, range 16 ng–3120 ng/g fine dust). Mite-allergen levels were significantly higher (P〈0.001) in floor dust than in carpets, and D. pteronyssinus predominated. In contrast, the levels of cat antigen were significantly (P〈0.05) higher in carpets than in floor dust. There was no clear relation between mite-allergen levels and type of house, except that the higher values were found in homes with dampness problems. Cat-allergen levels were higher than total mite-allergen content, and the highest levels were found in homes with a cat (P〈0.05). Rather high concentrations of cat allergen were also found in homes without a cat, which may explain why cat sensitization is so common in Sweden. As the prevalence of house-dust mite sensitivity is increasing in Swedish children, and as the individual patient threshold for eliciting symptoms varies, we suggest that sensitization may possibly occur at a lower exposure level than generally accepted as risk level for sensitization (2 μg/g dust).

Notes: Cord blood IgE was assayed in 164 newborn babies from the United Arab Emirates. The serum IgE levels ranged between ≤0.1–13.5 kU/1 with a geometric mean of 0.28 kU/1. The cord blood IgE in the 89 babies without immediate family history of allergy was ≤0.1–3.2 kU/1 with a geometric mean of 0.25 kUA and 1.13 kU/1 as the 90th percentile. An influence of prenatal sensitization to helminth antigens on cord blood IgE level was not likely. The data are similar to cord blood IgE values reported in other populations. This indicates that ethnic differences do not influence cord blood IgE levels and that previously published studies on the predictive value of cord blood IgE determination in Caucasians are relevant also for other populations.

Notes: The role of aluminium for IgG and IgE responses to pertussis toxin (PT), as well as for side effects, was investigated in 49 children with known atopy status. Primary immunization had been given with an adsorbed monocomponent or an adsorbed two-component acellular pertussis vaccine. The children were then randomized to receive a booster immunization with either aluminiumadsorbed or non-adsorbed, whole cell, pertussis vaccine. Both vaccines induced good IgG responses with the adsorbed vaccine giving higher post-booster levels (p 〈 0.05). The adsorbed vaccine was, however, associated with more local side effects (p 〈 0.05) and tended to induce higher PT-IgE responses than the non-adsorbed vaccine. Furthermore, individuals who had received the two-component vaccine as primary immunization had higher PT-IgE responses after the booster, compared with individuals initially receiving the monocomponent vaccine (p = 0.041). No correlation between PT-IgE and PT-IgG levels was seen in any of the groups. Total serum IgE levels correlated to PT IgE levels, particularly in children with atopy (r = 0.950, p 〈 0.001). The addition of aluminium to the pertussis vaccine, was, thus, associated with a stronger IgG antibody response, but tended also to induce a stronger IgE antibody response. The correlation between total IgE and PT-IgE, which was most prominent in children with atopy, indicates that the role of immunization for the development of allergy merits further studies.

Notes: The appearance and course of serum immunoglobulin E-antibodies (IgE-ab) to egg-white (EW). cow's milk (CM) and inhalants (pollen, danders and mite) were followed from birth to 12 years of age in 84 children unselected for family history of atopy. During the follow-up 36 children developed atopic symptoms and 48 children did not. IgE-ab to EW and CM reached a peak prevalence at 8 months of age — with high concentrations almost exclusively in atopies and disappeared successively during childhood. IgE-ab to inhalants appeared from 2 years of age and then in increasing frequency during childhood. Similar to the pattern of IgE-ab to EW and CM, transient low levels of IgE-ab to inhalants were commonly encountered in non-atopic children while high concentrations without tendency to decline were almost exclusively seen in atopies. High responders to EW-antigen during infancy were usually also high responders to inhalants during childhood. Clinical allergy to EW and CM and subsequent tolerance appeared early in childhood, whereas allergy to inhalants appeared later and did not disappear. The temporary low-grade IgE antibody response in non-atopic individuals to eaten and inhaled allergens is similar to the results of animal studies demonstrating a transient IgE production followed by tolerance.

Notes: The priming effect of a bacterial lipopolysaccharide (LPS) on subsequent respiratory burst activity induced by either the chemoattractant formylmethionyl-leucyi-phenylalaninc (fMLP) or phorbol myristate acetate (PMA; a protein kinase C activator) was studied in human ncutrophils isolated from cord blood and adult peripheral blood. Cells from adults, but not from newborn babies, were primed by LPS pretreatment. The content and release of β-glucuronidase and vitamin-B12 binding protein, or marker for the azurophilic and specific granules, respectively, was similar for cells from infants and adult controls. In contrast, alkaline phosphatase activity was significantly increased in the cord blood neutrophils compared to neutrophils from adult peripheral blood. The latency of the alkaline phosphatase activity was, however, similar. Thus, the primed response of cord blood neutrophils could not be explained by an increased release of azurophilic or specific granule content. If the increased alkaline phosphatase activity of curd cells represents an increased number of secretory vesicles, however, then this would indicate a rapid turnover leading to delivery of new receptors and oxidase components to the cell membrane.

Notes: Forty–three specimens of human milk were obtained from allergic and non–allergic women 3–6 days post–partum and analyzed for their eventual content of eosinophils and metachromatically staining cells. Eosinophils and metachromatically staining cells were identified in all milk samples; however, in lower numbers than in peripheral blood (0.082 to 4. 44% and 0.002 to 0.098% resp. of total cell numbers). Possible contamination of milk fluid with peripheral blood was ruled out. As no mast cells were detected with monoclonal anti–tryptase antibodies, the metachromatically staining cells were basophils. The numbers of basophils and eosinophils in milk were positively correlated to each other (p 〈 0.05) and to blood eosinophil counts (p0 〈 0.001 and p1= 0.01, respectively), suggesting migration of these cells from blood to the mammary glands. Significantly higher numbers of eosinophils, but not of basophils were encountered in milk of allergic women compared to milk of non–allergic mothers (p0 〈 0.01 and p1 〉 0.05, respectively). As histamine release in the gut increases gut permeability and thereby probably the risk for sensitization to food allergens, basophils in milk might represent an allergy risk factor for the suckling neonate.

Notes: Allergenicity and antigenicity of various commercially available cow milk hydrolysates intended for infant feeding were analysed in 45 children with cow milk allergy. The hydrolysates included the whey hydrolysates Beba HA® (Good Start HA®) and Profylac®, and the casein hydrolysates Alimentum® and Nutramigen®. Positive skin prick tests were recorded against Beba HA in 10 of 41 tested children (24%), against Profylac® in 5/34 (15%) and in one each (2.5%) against Alimentum and Nutramigen. Double-blind placebo-controlled oral challenge tests were performed in 11 children with cow milk allergy using Alimentum, cow milk (positive control) and their regular well-tolerated formula (Nutramigen or soy) used as negative control. One child reacted to Alimentum. This patient was the only one with circulating antibodies against the product, as indicated by a positive RAST. High density SDS-PAGE electrophoresis showed that Beba HA contained a number of unresolved proteins, and non-degraded or partially degraded whey proteins in the range of 5–20 kD. Profylac contained strongly stained protein material in the low molecular weight region 1–10 kD. No protein bands could be identified in the casein-based hydrolysates. Residual antigenicity was tested by measuring the content of betalactoglobulin in the hydrolysates. Three of the hydrolysates contained 〈 0.06 μg/g dry weight, while the concentration in Beba HA was 200 μg/g dry weight. Positive RAST against Beba HA was detected in 11/45 sera (24%) compared to 7–13% against the other hydrolysates. RAST inhibition with the hydrolysates using cow milk discs was very low for all of them. Using dot immuno-binding assay a weak IgE binding with Alimentum was detected in 4 sera, Beba HA and Profylac in each 2 sera and with Nutramigen in one. The data taken together show that all 4 tested hydrolysates retain some allergenicity. There were differences between the products, one of the whey hydrolysates being substantially more allergenic and antigenic than the other tested formulas. The casein hydrolysate Alimentum showed few reactions in vivo and in vitro in this selected group of children but one child reacted when challenged with Alimentum, indicating that there is a risk for general reactions when using any hydrolysed product in subjects allergic to cow milk.

Notes: The appearance of metachromatic cells in nasal scrapings was studied prospectively in 67 children from birth to 18 months of age. The findings were related to family history of atopy and development of allergic disease in the infants. Allergic disease was diagnosed during the 18-month follow-up period in 54% of the infants with heredity for atopic disease. The corresponding figure for children with no heredity was 11%. Using a gentle scraping-cytocentrifugation method for collection of mucosal specimens, metachromatic cells were identified in the nasal scrapings in 20 of 30 children who developed definite allergic disease (67%) and in 6 of 9 with probable allergy. The cells appeared before or at the time of diagnosis in 19 of the infants with definite allergic disease. Metachromatic cells were also found in 7 of 25 healthy children who did not develop allergic disease during the follow-up period. Six of them had definite and one possible heredity for allergic disease. No metachromatic cells were found in any of the 8 infants who lacked heredity for atopy and did not develop atopic disease. In conclusion, the appearance of metachromatic cells in the nasal mucosa during the first 18 months of life of infants was associated with atopic propensity, as defined by development of atopic disease and/or a strong family history of allergy.

Notes: Allergic sensitization and symptoms from the airways in relation to air pollution were compared in 10–12-year-old school children (n= 1113) from urban Konin in central Poland and both urban and rural parts of Sundsvall in northern Sweden. The measurements included parental questionnaires, skin-prick tests and serial peak flow measurements during 2 weeks with simultaneous monitoring of outdoor air pollutants. The skin-prick test technique was validated by IgE antibody determinations. The levels of common industrial pollutants, SO2 and smoke particles were much higher in Konin than in urban Sundsvall and the levels of NO2 were similar. Various respiratory symptoms were more often reported among school children in Konin (except for wheezing and diagnosed asthma). Multiple logistic regression analyses yielded the following increased odds ratios for children in Konin as compared with the reference group (rural Sundsvall): chest tightness and breathlessness 348 (95% confidence interval 2.08–5.82), exercise-induced coughing attacks 3.69 (95% confidence interval 1.68–8.10), recurrent episodes of common cold 2.79 (95% confidence interval 1.53–5.09) and prolonged cough 4–89 (95% confidence interval 2.59–9.23). In contrast, as compared with rural Sundsvall, the adjusted odds ratio for a positive skin-prick test was decreased in Konin, but increased in urban Sundsvall, 0.58 (95% confidence interval 0.37–0.91) and 1.67 (95% confidence interval 1.15–2.42) respectively. The study confirms that living in urban, as compared with rural areas, is associated with an increased prevalence of respiratory symptoms and sensitization to allergens. These differences could be explained by air pollution. Respiratory symptoms were more common in a similar urban group of Polish children who were exposed to even higher levels of air pollution. These children, however, had a much lower prevalence of sensitization to allergens, as compared with the Swedish children. This indicates that differences in lifestyle and standard of living between western Europe and a former socialist country influences the prevalence of atopy.