Cell-surface expression of CD25, CD26, and CD30 by allergen-specific T cells is intrinsically different in cow's milk allergy.

Background: The release of T(H)2 cytokines by food-specific T cells is thought to be important in the etiology of food allergy. It has been suggested that the activation state of food-specific T cells also plays a significant role, but this has not yet been studied at the single-cell level.

Objective: Differences in the expression of cell-surface markers by cow's milk protein (CMP)-specific T cells between infants with and without cow's milk allergy (CMA) were evaluated at the clonal level.

Quantification of major peanut allergens Ara h 1 and Ara h 2 in the peanut varieties Runner, Spanish, Virginia, and Valencia, bred in different parts of the world.

Background: The serology of peanut allergy seems to be different in various parts of the world. We analyzed the composition of 13 samples of three varieties of peanut in order to compare their allergenic nature.

Methods: Peanut cultivars that are commonly processed in the West were analyzed for protein content, protein composition, and Ara h 1 and Ara h 2 content by biochemical methods.

Differences in antigen-specific T-cell responses between infants with atopic dermatitis with and without cow's milk allergy: relevance of TH2 cytokines.

Background: Cow's milk is the most important food antigen in infancy and may lead to acute cutaneous symptoms and atopic dermatitis (AD). The role of circulating allergen-specific T cells in the pathogenesis of food-allergic skin symptoms is still under investigation.

Objective: This study was designed to analyze the cow's milk protein (CMP)-specific T-cell response at the clonal level in infants with AD and cow's milk allergy (CMA) in comparison with infants with AD without CMA.

IgE production after antigen-specific and cognate activation of HLA-DPw4-restricted T-cell clones, by 78% of randomly selected B-cell donors.

The frequency of expression of the MHC class II antigen, HLA-DPw4, in the caucasoid population is approximately 78%, and is unmatched by phenotypic frequencies of other HLA class II molecules. Here we describe three human Der-P1-specific T-cell clones (TCC), restricted by the HLA-DPw4-variant HLA-DPB1*0401, of which two TCC also responded to antigen, presented on HLA-DPB1*0402. Thus, randomly selected caucasoid donors present a 78% chance for a correct match with these HLA-DPw4-restricted TCC.

Clinical and immunologic variables in skin of patients with atopic eczema and either positive or negative atopy patch test reactions.

Background: Epicutaneous application of aeroallergens induces a positive atopy patch test (APT) response in about 50% of patients with atopic eczema (AE) and sensitization for these allergens.

Objective: To elucidate the mechanisms determining the outcome of the APT, the following questions were addressed. Are there differences in clinical features between patients with AE who have positive versus negative APT responses? Is a macroscopically negative APT response also histologically negative, and if so, are there differences in clinically noninvolved skin between the two groups regarding (1) the sensitivity toward an irritant, (2) the composition of cellular infiltrate, (3) the presence of aeroallergen-specific T cells, and (4) the number of IgE(+) cells?

Methods: Punch biopsy specimens from both house dust mite patch tested and the clinically noninvolved skin of patients with AE who have positive APT responses (n = 10) and negative APT responses (n = 10) and those from the normal skin of atopic individuals without AE (n = 10) and nonatopic volunteers (n = 10) were analyzed by using immunohistochemistry with mAbs against eosinophil cationic protein, IgE, the high-affinity receptor for IgE, and CD3 and CD25 mAbs.