A Ekberg-Jansson

Relationship between inflammatory cells and structural changes in the lungs of asymptomatic and never smokers: a biopsy study.

Background: A study was undertaken to investigate the relationship between inflammatory cells and structural changes in the mucosa of the airways in an epidemiological sample of a group of asymptomatic smokers (smokers who had never sought medical attention for respiratory problems) and in non-smoking subjects. Methods: Bronchial biopsy specimens were taken from 29 smokers and 16 never smokers and stained with monoclonal antibodies HNL, EPO, AA1, CD68 in order to identify neutrophils, eosinophils, mast cells, and macrophages, respectively. The biopsy specimens were also stained with monoclonal antibodies to the cytokines interleukin (IL)-1β and IL-8. Structural changes were identified by staining the biopsy specimens with antibodies to tenascin and laminin and by evaluating the condition of the epithelial layer. Results: The numbers of all inflammatory cells and of cytokine staining cells were significantly increased in smokers. The thickness of the tenascin and laminin layers was increased in the smoking group and the integrity of the epithelial layer was significantly reduced. In smokers the epithelial integrity was negatively correlated with the number of eosinophils and macrophages. The thickness of the tenascin and laminin layers was positively correlated with AA1 and EPO positive cells only. Conclusion: High numbers of inflammatory cells are present in the bronchial mucosa of asymptomatic smokers which have a clear relationship with the impaired epithelial integrity. The increased thickness of the laminin and tenascin layers in these subjects was strongly related to the presence of eosinophils and mast cells, suggesting a role for these cells in tissue remodelling of the airways of smokers.

High-resolution computed tomography in healthy smokers and never-smokers: a 6-year follow-up study of men born in 1933.

Purpose: To elucidate whether emphysematous lesions and other high‐resolution computed tomography (HRCT) findings considered associated with smoking are part of a progressive process, and to measure the extent to which similar changes are found in never‐smokers. Material and Methods: Healthy smokers and never‐smokers were recruited from a randomized epidemiological study and investigated with a 6‐year interval. Emphysema, parenchymal and subpleural nodules, ground‐glass opacities, bronchial alterations, and septal lines were evaluated in 66 subjects (40 smokers, 11 of whom had stopped smoking in the interval, and 26 never‐smokers). Lung function was tested. Results: All except emphysematous lesions were present to some extent in never‐smokers. Emphysema, parenchymal nodules, and septal lines occurred significantly more in current smokers, and a progression in extent of emphysema, ground‐glass opacities, bronchial alterations and septal lines was seen. There was no significant change among those who stopped and never‐smokers except for bronchial alterations, which progressed in never‐smokers. Conclusion: In healthy, elderly never‐smokers a low extent of various HRCT findings has to be considered normal. Emphysema, parenchymal nodules, and ground‐glass opacities are indicative of smoking‐induced disease. Further progress may cease if smoking is stopped.

A comparison of the expression of lymphocyte activation markers in blood, bronchial biopsies and bronchoalveolar lavage: evidence for an enrichment of activated T lymphocytes in the bronchoalveolar space

In this study healthy never-smoking subjects (n = 18) were recruited from a population study. Bronchoalveolar lavage (BAL), blood lymphocytes and bronchial biopsies, analysed both in the epithelium and lamina propria, were stained for T and B lymphocytes, natural killer (NK) cells and different subpopulations of T lymphocytes. In BAL, significantly higher proportions of T lymphocytes (CD3), T lymphocyte activation markers; HLA-DR, CD26+, CD49a+, CD54+ and CD69+, helper T (CD3+4+) and memory helper T lymphocytes (CD4+45RO+29+) and memory T lymphocytes (CD3+45RO+) were found, compared to blood. However, the proportion of IL-2 receptor-positive T lymphocytes (CD25+) was lower in BAL than in blood. A previously described higher ratio of CD3+4+/CD3+8+ in BAL than in blood (3.4 vs 1.7; P = 0.001) was confirmed. In bronchial biopsies, we found significantly higher numbers of CD8+ cell profiles per mm2 in the epithelial compared to the lamina propria compartment. We conclude that healthy never-smoking men have higher levels of activated memory T lymphocytes in BAL than in blood, and that the T-cell subpopulations differ in the epithelial compared to the lamina propria compartment in the bronchial mucosa and these compartments should be analysed separately. It is reasonable to think that there is a gradient from blood to the airway lumen where T cells are recruited from blood to take part in the defense towards damaging agents.

Detection of mild emphysema by computed tomography density measurements

Purpose: To assess the ability of a conventional density mask method to detect mild emphysema by high‐resolution computed tomography (HRCT); to analyze factors influencing quantification of mild emphysema; and to validate a new algorithm for detection of mild emphysema. Material and Methods: Fifty‐five healthy male smokers and 34 never‐smokers, 61–62 years of age, were examined. Emphysema was evaluated visually, by the conventional density mask method, and by a new algorithm compensating for the effects of gravity and artifacts due to motion and the reconstruction algorithm. Effects of the reconstruction algorithm, slice thickness, and various threshold levels on the outcome of the density mask area were evaluated. Results: Forty‐nine percent of the smokers had mild emphysema. The density mask area was higher the thinner the slice irrespective of the reconstruction algorithm and threshold level. The sharp algorithm resulted in increased density mask area. The new reconstruction algorithm could discriminate between smokers with and those without mild emphysema, whereas the density mask method could not. The diagnostic ability of the new algorithm was dependent on lung level. At about 90% specificity, sensitivity was 65–100% in the apical levels, but low in the rest of the lung. Conclusion: The conventional density mask method is inadequate for detecting mild emphysema, while the new algorithm improves the diagnostic ability but is nevertheless still imperfect.