Chemokines and their receptors in chronic pulmonary disease.

The incidence of asthma has continued to rise worldwide with the number of severe asthmatic episodes dramatically increasing especially in children. Over the past several years researchers have realized that by controlling the influx of inflammatory cells that damage the airway and perpetuate the chronic responses, asthmatic disease can be attenuated. The modulation of the immune/inflammatory response has been primarily managed by use of inhaled and/or oral steroids. However, more specific therapy focused on inflammatory cell influx is desired to target the appropriate cell populations and alleviate specific aspects of disease without non-specific side effects. The chemokine family of cytokines control recruitment of leukocyte populations through specific receptors that are differentially expressed by certain cellular populations in various immune environments. Defining the type of receptors that are displayed by key cell populations involved in asthmatic responses has been the focus of many academic and pharmaceutic programs. This review will highlight the various areas that have been identified and those that appear to provide a future for therapeutic intervention.