The Oettgen laboratory focuses on IgE--the antibody that mediates allergic reactions--and its influence on mast cells, which produce cytokines--chemicals involved in the inflammatory response. The team is currently examining the effects of IgE levels on the types and volume of cytokines in mast cells of the skin. They are also studying how IgE influences mast cell stability and analyzing the how IgE regulates immune sensitization in the skin and lungs.

People with allergies produce large amounts of IgE antibodies, which circulate in the blood and bind to IgE receptors in mast cells in the lungs, gastrointestinal tract, skin and other organs. Some IgE antibodies recognize specific allergens, including foods, insect venoms, drugs and airborne particles such as pollens and animal danders. Allergic reactions are triggered when mast cell-bound IgE encounters specific allergen, leading to receptor aggregation, mast cell activation, and the release of histamine, prostaglandins, leukotrienes and cytokines. This antigen-driven cross-linking of mast cell-bound IgE is what triggers acute asthma attacks or anaphylaxis.

IgE antibodies can also exert antigen-independent effects. For instance, IgE, even in the absence of allergen, increases the number of IgE receptors, mast cell survival, and cytokine production. Thus high levels of IgE, which are invariably present in allergic individuals, may not only drive acute allergic reactions but also regulate many other aspects of the immune response. Oettgen's studies aim to define the precise molecular and cellular pathways through which IgE antibodies regulate immune functions. A better understanding of the allergic process should enable physicians to more effectively use the new anti-IgE therapies.