[A chance for the prevention of atopic diseases].

The proposed concept links the alterations in cell-mediated and humoral immunity in atopy to impaired prostaglandin E (PGE)-mediated thymic maturation of T-suppressor lymphocytes and diminished activation of T-suppressor lymphocytes of the peripheral atopic immune system. The decreased sensitivity of atopic T lymphocytes to PGE, recently explained by a reduction of PGE2-receptors on atopic lymphocytes, is regarded as the common underlying defect in atopy. A second defect, the delta-6-desaturase deficiency, affects the regular supply of the PGE-precursors dihomo-gamma-linolenic acid and arachidonic acid and predisposes for atopic dermatitis. Furthermore, the composition of omega-6-fatty acids in breast milk of atopic mothers represents a delta-6-desaturase deficiency. Substitution of the delta-6-desaturase product gamma-linolenic acid to the atopic pregnant and nursing woman and her newborn infant at increased risk for atopy offers a chance for the prevention of atopic diseases.