Abstract

BACKGROUND--Bronchial epithelial function after heart-lung transplantation (HLT) for cystic fibrosis (CF) may be affected by the original disease as well as other factors such as prolonged organ ischaemic time, the interruption of bronchial arterial and lymphatic supply, infection, rejection, and cyclosporin. In vitro measurement of the bioelectric properties of the bronchial mucosal lining may be an effective means of characterising the mucosal function of the lung allografts in response to pharmacological agents. METHODS--Bronchial mucosal tissues from explanted native lungs of CF and non-CF patients at transplantation were used to assess the possible application of a mini-Ussing chamber. With this technique, the bioelectric responses of bronchial mucosal biopsies from six patients with CF, one patient with congenital heart disease, four with primary pulmonary hypertension, and one with emphysema, all after HLT, were studied. The bioelectric and pharmacological responses of biopsies of bronchial mucosa from patients after HLT were compared with biopsies from non-CF non-HLT subjects. RESULTS--The altered bioelectric properties of CF tissues could be detected by the mini-Ussing chamber technique. The basal bioelectric values and the responses to amiloride and isoprenaline in CF patients were not different from those in non-CF patients two years after HLT. No significant difference in the basal bioelectric properties and responses to amiloride and isoprenaline was found between HLT recipients and non-CF non-HLT subjects. CONCLUSIONS--The mini-Ussing chamber is an effective means of characterising the typical CF bioelectric defect which was not found in the transplanted lungs of CF patients up to two years after HLT. Furthermore, values were unaltered in comparison with non-transplanted lungs, suggesting that bronchial epithelial function is maintained after HLT.