Molecular mechanisms of asthma: We are studying how substances produced by the immune system contribute to allergic reactions in the lungs and to asthma, a disease that affects more than 10 million Americans annually. Cytokines produced by T cells and other immune cells in during allergy and during infection act on resident airway cells, including epithelial cells, smooth muscle cells, and fibroblasts, to produce many of the important features of asthma. We have used transgenic mouse models and cell culture systems to identify some of the key pathways.

One of the most important Th2 cytokines is interleukin-13 (IL-13). We found that IL-13 acts directly on airway epithelial cells to induce mucus production and airway hyperreactivity, two abnormalities that are important contributors to morbidity and mortality in asthma and other airway diseases. We have identified genes that are activated by IL-13 and are now studying how these genes play a role in pathology.

Functional genomics of lung diseases: The sequencing of the human genome marks the beginning of a new era in biological research. Dr. Erle directs the Sandler Asthma Basic Research (SABRE) Functional Genomics Core, which assists investigators using DNA microarray technology to investigate a wide range of questions relevant to asthma and other diseases. In addition, Dr. Erle's group is investigating how small RNAs (especially micro-RNAs) and other factors that bind to the 3' untranslated regions of messenger RNAs regulate gene expression.