Bradley Winston Richmond, M.D.

While most patients with chronic obstructive pulmonary disease (COPD) are current or former smokers, only some smokers develop severe COPD. Differences in frequency or response to recurrent infection may explain why only some smokers develop COPD. Our preliminary data shows that the small airways of COPD patients frequently lack secretory immunoglobulin A (SIgA), a protein whose main role is to prevent bacteria from penetrating into the lung. Using mice engineered to lack SIgA, we will examine whether the lack of this protein results in COPD-like lung injury after exposure to bacteria, and whether restoring SIgA in the small airways will prevent these changes from taking place.