[Cytokines and allergic response].

Allergic reactions are under the control of several events that occur sequentially following allergen exposure, recognition by the immune system, IgE production and their interaction with effector cells bearing Fc epsilon receptors. The lymphocyte activation in response to allergens determines the intensity and the nature of the immune response. Cytokines produced by T (and non-T) cells are involved in the polarized development of the specific immune response. In particular, type 1 and type 2 cytokines are responsible for the control of the different steps during allergic reactions. Th2 cytokines and particularly IL4 are responsible for switching the immunoglobulin synthesis by B cells to IgE production. They also play a key role in the activation of effector cells that occurs following allergen interaction with fixed specific IgE and participate to the local inflammatory reaction. Cytokine profile determination appears to represent a helpful laboratory parameter in the understanding of the mechanisms underlying allergic diseases. The development of new technological tools may allow the use of cell activation parameters, and cytokine profiles determination in clinical biology. This review aims to analyze the involvement of the cytokine network in the mechanisms leading to IgE production and the involvement of cytokines in effector mechanisms of allergic reactions. It also analyses the potential use of cytokine profile determination for diagnosis purpose and survey of immune desensitization of allergic diseases.