In this study we evaluated antigen‐specific in vitro responses of peripheral blood lymphocytes to lipopoiysaccharide (LPS)‐depleted food allergens in children who reacted to food challenge (cow's milk or hen's egg) with a deterioration of their atopic dermatitis (AD). Some ofthe children showed immediate symptoms (urticaria, bronchial asthma or gastrointestinal symptoms) as well. The proliferation of casein‐stimulated lymphocytes from children reacting to cow's milk (age (0.7–5.9 years) was significantly higher (P<0.01) than the proliferation of lymphocytes from 15 children with AD without milk allergy (age: 2.1–9.1 years). Twenty‐eight T‐cell clones (TCC) were established from the blood of three children sensitized to cow's milk and hen's egg who reacted to double‐blind, placebo‐controlled oral food challenge both with a deterioration of AD and wilh immediate symptoms. Surprisingly, 16 of 28 casein‐ or ovalhumin‐specific TCC were CD8+. All TCC produced high amounts of IFN‐γ upon stimulation with concanavalin A. In addition. 75%. of the CD4+ TCC and 44% of the CD8+ TCC secreted IL‐4. Our results indicate that: (i) food‐specific proliferation of blood lymphocytes can be detected in patients with clinically relevant food allergy with LPS‐depleted allergens in vitro and (ii) circulating food‐specific lymphocytes are CD4+ and CD8+ T cells with the capacity of producing both type 1 and type 2 cytokines.