%0 Journal Article %T Update on Allergy Immunotherapy %A William Davidson %A Sean Lucas %A Larry Borish %J Allergy, Asthma & Clinical Immunology %D 2005 %I BioMed Central %R 10.1186/1710-1492-1-4-161 %X This article summarizes and provides commentary regarding current guidelines on the administration of immunotherapy (IT) for allergic airway disease. Details on currently accepted practices in the preparation and administration of IT are published elsewhere [1-5], and allergy practitioners are advised to use these references as the standard of care. This article draws primarily on recent studies regarding the current understanding of the mechanism and proper administration of IT (with emphasis on the importance of properly dosing major allergen content) and on current insights into the selection of patients and allergens for IT. Finally, several recent studies have reported on issues of morbidity and mortality associated with IT and emphasize particularly the importance of postponing administration of IT at times when asthma is poorly controlled.Several mechanisms of IT have emerged over recent decades, reflecting an increased understanding of immunology. Early studies concentrated on increases in allergen-specific immunoglobulin (Ig) G, specifically that of the IgG4 isotype. These immunoglobulins were proposed as "blocking" immunoglobulins that competed with IgE for allergen binding to IgE receptor-expressing cells. However, the correlation between IgG concentrations and clinical response to treatment is weak, and even when correlated to nasal IgG (or IgA) concentrations in the allergic inflammatory milieu, no improvements in these relationships were observed.More recently, immunodeviation has been cited, with reductions in T-cell proliferative responses to allergens and a shift from a T-helper 2 (Th2)-like response toward a Th1-like response following immunotherapy [6]. Unfortunately, this model also comes under scrutiny because (1) T cells that produce interferon (INF)-¦Ã (Th1-like cells) are a characteristic feature of allergic inflammation, (2) IFN-¦Ã is a potent proinflammatory compound that contributes to both the presence and severity of allergic disease [7], %U http://www.aacijournal.com/content/1/4/161