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Background: The hypothesis that in atopic diseases the T-helper response is skewed toward a T H 2-type cytokine response was based on studies with mitogen stimulation, T-cell clones, or both. Objective: Using primary cultures, we investigated (1) whether atopic asthmatic patients have a T H 2 response and nonatopic subjects have a T H 1 response to allergen and (2) whether atopic patients have a decreased ability to mount T H 1 immune responses to mycobacterial antigens. Methods: The responses of PBMCs to allergen (house dust mite [HDM]) or purified protein derivative of Mycobacterium tuberculosis (PPD) stimulation from 10 severely and 14 moderately asthmatic patients (all allergic to HDM) were compared with those of 17 nonatopic healthy black (Xhosa) children. Results: HDM-stimulated proliferation, IL-5 release, and the IL-5/IFN-γ ratio were significantly increased in subjects with atopic asthma, whereas IFN-γ release was not significantly different. IL-4 levels were below the level of detection. PPD-stimulated proliferation, IL-5 release, IFN-γ release, and the IL-5/IFN-γ ratio were not significantly different among the groups. Each group had a significantly higher IL-5/IFN-γ ratio in response to HDM than to PPD (a T H 1 stimulus). Conclusion: Our study, which used primary cultures to investigate the hypothesis that nonatopic subjects have a T H 1 response to allergens, indicates that HDM stimulates a T H 2 cytokine response in both atopic and nonatopic subjects but that the response is enhanced in atopic patients. Our results with PPD suggest that normal and atopic asthmatic subjects can have a T H 1 cytokine response to mycobacteria, but there is a subgroup of atopic subjects that have a T H 2 response. (J Allergy Clin Immunol 2000;106:84-91.)

Rationale Allergen sensitization is an important risk factor for allergic disease, including allergic rhinitis. This study reports the sensitization status, and efficacy of fexofenadine (FEX), in a subset of children (aged 6–11 yrs) from the Southern Hemisphere with seasonal allergic rhinitis (SAR) enrolled into a large, placebo-controlled, randomized, parallel-group study. Methods For randomization, children required a positive skin prick test to at least one pollen allergen for the current season and concordance to that specific allergen in in vitro IgE testing. Specific IgEs were determined by the Fluoro Enzyme Immuno Assay; positive IgE was defined as IgE class ≥2 (>0.7 kUA/L). Analysis was performed on the modified intention-to-treat (mITT) population, treated with either FEX HCl 30 mg BID or placebo. Efficacy was evaluated as the overall mean change from baseline in 12-hour reflective total symptom score (TSS). Results A subset of 300 subjects (FEX, n=145; placebo, n=155), from 40 centers in Argentina, Chile, Uruguay and South Africa, was analyzed. Sensitization to pollen allergens assessed by plant category showed that grasses were the most common group of allergens (>93%); sensitization to weeds was 8.9% for FEX and 17.8% for placebo; sensitization to trees was 20.5% for FEX and 20.4% for placebo. FEX significantly improved the mean change from baseline in TSS compared with placebo ( p Conclusions In this subset of children from the Southern Hemisphere, grasses were the most common groups of sensitizing allergens. Furthermore, FEX significantly improved the symptoms of SAR in this population of children.

Raised concentrations of cord blood serum (CBs) IgE have previously been demonstrated to reflect a hereditary predisposition for atopy in First World, predominantly white populations. A cross-sectional study of 53 black, 52 white, and 58 mixed race newborn infants and maternal pairs was performed in a multiethnic, mixed First and Third World society. The CBs IgE concentrations were measured with a modification of the standard IgE PRIST, which could reliably determine IgE concentrations to an accuracy of 0.01 kU/L. The black group had the highest geometric mean and median CBs IgE concentrations (0.21; 0.16 kU/L), followed by the white group (0.12; 0.12 kU/L) and the mixed group (0.10; 0.08 kU/L). If those newborn infants with an atopic family history and maternal ascariasis were excluded, the remainder had geometric mean and median CBs IgE concentrations of 0.20; 0.16 kU/L in the black subgroup, followed by values of 0.06; 0.05 kU/L in the mixed subgroup, and 0.05; 0.07 kU/L in the white subgroup. Statistically significant ethnic differences in the median CBs IgE concentrations of these subgroups were demonstrated between the black-white (p less than 0.05) and the black-mixed (p less than 0.005) ethnic groups. A positive family history of atopy influenced the CBs IgE concentrations in the white and mixed groups but not in the black group. Of those newborn infants with a CBs IgE concentration greater than 0.5 kU/L, a family history of atopy was found in 100% of the white newborn infants, in 58.3% of the mixed newborn infants, and only in 14.3% of the black newborn infants. Many of the black newborn infants without a family history of atopy had extremely high CBs IgE concentrations. The influence of maternal ascariasis was equivocal in the mixed group but of no significance in the black group. The high CBs IgE concentrations in the black newborn infants, independent of an atopic family history and maternal ascariasis, suggest that this atopic marker may therefore be of limited use in identifying the "high allergic-risk" newborn infant in black Third World populations who appear to represent a pool of genetic high IgE-responder phenotypes.

Serum samples from 60 adults and 64 children with atopic dermatitis were tested for antistaphylococcal IgE antibodies with RAST discs coupled to cellular proteins from Wood 46 strain S. aureus. Anti- S. aureus IgE antibodies were detected in 19 (29.6%) of the children and 14 (23.3%) of the adult patients. Anti- S. aureus IgE-positive adults had more severe and prolonged disease than those who were negative. Two groups of children comprising 10 who were anti- S. aureus IgE positive and 10 who were negative were compared. Children with anti- S. aureus IgE antibodies had more severe and more extensive disease ( p S. aureus infections ( p p p p

Forty-two chronic asthmatic children, including 10 with associated eczema, were examined for lenticular complications. The children had received oral corticosteroids for a minimum of 3 years. Twelve were treated with beclomethasone inhalant therapy, and the children with eczema had had topical corticosteroids. Only one child was found to have cataracts commensurate with corticosteroid therapy. Possible reasons for the low incidence of cataracts in this study are discussed.