Interleukins-4, -5, and -13: Emerging therapeutic targets in allergic disease

For the first time, allergic diseases have emerged as major public health concerns. Highly effective therapies for allergic disease now exist, but are plagued by serious side effects and the fact that a significant minority of patients remains unresponsive. Studies from many laboratories have established that T helper type 2 (T_H2) cytokines contribute importantly to diseases such as asthma, and therapeutic strategies that target the key T_H2 cytokines are of potential benefit in allergic disease. In this article, we will review the biology of the T_H2 cytokines interleukin (IL)-4, IL-5, and IL-13 and their receptors, and will consider several novel strategies to neutralize these molecules in human and experimental asthma. While promising, newer therapies face a gauntlet of developmental challenges, but offer the hope of reducing allergic diseases once again to minor public health concerns.