Airway epithelium of transplanted lungs with and without direct bronchial artery revascularization

Objective: Normal systemic blood flow to the airways and lung parenchyma of transplanted lungs can only be re-established by direct bronchial artery r evascularization. The purpose of the present study was to investigate wheth er such direct bronchial artery revascularization would preserve ciliary fu nction, previously shown to be reduced in lungs transplanted without revasc ularization. Methods: Twenty-five single lung transplanted patients were in cluded in this study. Complete direct bronchial artery revascularization wa s achieved in eight patients. In 16 patients the procedure had either faile d (n = 10) or was not attempted (n = 6). In one patient the result of the r evascularization was unknown. Airway epithelium samples were obtained from the native and the transplanted lungs during bronchoscopic examinations. Ai rway erythema and excessive secretion were registered. The epithelium sampl es underwent histological examination and ciliary beat frequency was measur ed in vitro by video recording. Transbronchial biopsies from the transplant ed lungs were examined for signs of rejection and bronchitis. Results: No d ifferences in ciliary beat frequency nor in the distribution of ciliated/de -ciliated columnar epithelium cells between native lungs and transplanted l ungs with or without successful direct bronchial artery revascularization c ould be demonstrated. In 38% of the transplanted lungs without successful r evascularization metaplastic or squamous epithelium was present, while lung s with successful revascularization had only normal columnar epithelium. On going rejection or airway erythema did not influence ciliary beat frequency . Excessive secretion in the airways was the only finding associated with s ignificantly increased ciliary beat frequency. Conclusions: Ciliary beat fr equency of epithelium cells of transplanted lungs did not differ from that of native lungs and consequently direct bronchial artery revascularization did not have any demonstrable important influence. Excessive secretion in t he airways was associated with increased ciliary beat frequency. The histol ogical findings also showed that the abundance of ciliated cells was preser ved in transplanted bronchi irrespective of bronchial artery revascularizat ion. However, epithelium metaplasia was only seen in transplanted bronchi w ithout revascularization. (C) 1999 Elsevier Science B.V. All rights reserve d.