Cigarette smoke inhibits the growth of lung fibroblasts from patients with pulmonary emphysema

Objective: To investigate the proliferative characteristics of fibroblasts cultured from emphysematous lungs. Methods: Fibroblasts were isolated and cultured from emphysematous lungs surgically resected as a consequence of lung volume reduction surgery and from non-cancerous areas of lungs obtained following resection for lung cancer as a non-emphysematous control. Their proliferative activities were compared, as was the effect of cigarette smoke extract (CSE) on fibroblast proliferation. After incubation with various concentrations of CSE, cells were harvested and cell numbers were counted. Growth curves were constructed and doubling time was calculated to compare the proliferative activity of fibroblasts from emphysematous and non-emphysematous lungs. Results: The proliferation of fibroblasts from emphysematous lungs cultured with normal medium appeared suppressed compared with non-emphysematous lungs. The addition of CSE to the medium induced more obvious growth inhibition in emphysematous lung fibroblasts. The growth of both fibroblast cultures was inhibited by CSE and this appeared to be concentration dependent. Conclusions: Fibroblasts from emphysematous lungs had lower proliferative activity and were more susceptible to cigarette smoke than those from non-emphysematous lungs. Cigarette smoke may play a critical role in the development and deterioration of pulmonary emphysema by suppressing the growth of lung fibroblasts.