DISTRIBUTION OF GAMMA-DELTA-T-CELLS IN THE BRONCHIAL TREE OF SMOKERS AND NONSMOKERS

Aims-To assess the distribution of gammadeltaT-cells in the human bron chial tree; and to compare quantitatively the differences between gamm adeltaT-cell numbers in different parts of the airway wall in smokers and non-smokers. Methods-Full thickness bronchial wall sections were t aken from 10 whole lung specimens from both smokers and non-smokers. S erial cryostat sections stained with the monoclonal antibodies CD3 and TCRdelta-1 were examined with the aid of interactive image analysis t o assess gammadeltaT-cell numbers both in absolute terms and as a prop ortion of total T lymphocyte numbers. Results-In all cases gammadeltaT -cells were demonstrable throughout the airway wall. Although in absol ute terms they tend to occur predominantly in the bronchial epithelium , this seems to reflect higher numbers of T lymphocytes in the epithel ium in general compared with the submucosa. No genuine epitheliotropis m is evident. Comparison by smoking status shows a significant increas e in gammadeltaT-cell numbers in the bronchial glands of smokers compa red with non-smokers. Conclusions-gammadeltaT-cells form an integral t hough variable component of the immunocompetent cell population of the human airway in both smokers and non-smokers. Although epitheliotropi sm does not exist in the bronchial tree, gammadeltaT-cells seem to for m a significant part of the bronchial gland inflammation associated wi th smoking.