Peptide-mediated immune responses in specific immunotherapy

Conventional immunotherapy using whole allergen extracts has been shown to be an effective, disease-modifying treatment in carefully selected patients with allergic conjunctivo-rhinitis, asthma and bee and wasp venom hypersen sitivity. However, this form of therapy is associated with the risk of syst emic anaphylaxis, which, when severe, can be life threatening. A potentiall y significant reduction in the incidence of IgE-mediated events during immu notherapy may be achieved by the use of short peptides corresponding to T c ell epitopes which, by virtue of their size, are incapable of cross-linking allergen-specific IgE bound to the surface of mast cells and basophils, In itial clinical studies have demonstrated degrees of efficacy which have, in some cases, been associated with adverse events occurring immediately or s everal hours after peptide administration. Preliminary data from studies em ploying shorter peptides (20 amino acids or less) suggest that improved eff icacy may be achieved by using peptides of defined major histocompatibility complex-binding specificity administered in an incremental dose fashion co mparable to conventional immunotherapy. This review will discuss the concep t of peptide immunotherapy and the implications of recent studies, Copyrigh t (C) 2000 S. Karger AG, Basel.