Smoker's lung transplanted to a nonsmoker - Long-term detection of smoker's macrophages

Alveolar macrophages (AM) from smokers contain characteristic smoker's inclusion bodies within the cytoplasm as a result of ingestion of substances in the inhaled smoke. How long these smoking-related changes in the AM population can be seen after smoking cessation is largely unknown. We had the unique opportunity to investigate a 51-yr-old never-smoker after single lung transplantation (TX) for alpha 1-antitrypsin deficiency emphysema who received a donor's lung from a heavy cigarette smoker. Serial bronchoalveolar lavage (BAL) was performed in the donor's lung for transplant surveillance at defined time intervals, and the percentage of AM with characteristic smoker's inclusions was counted on slides stained with May-Grunwald-Giemsa stain. The patient had an uneventful course after TX with no major infectious complications or episodes of rejection. One month after TX the percentage of smoker's AM was 98%. BAL after 2, 5, 7, and 12 mo showed a similar high percentage. After 18 mo a first a decrease was seen, down to 78%, and after 2 yr a decrease to 59% was seen. After 3 yr, the smoker's AM had mostly disappeared, only 3% were still present. In conclusion, smoker's inclusions in AM may be detected for at least 2 yr after smoking has ceased, which is considerably longer than the estimated life span of the AM.