T-Lymphocytes - Chronic Obstructive Pulmonary Disease - page 217

clear correlation between the number of CD3 þ T-cells and the extent of
emphysema was found, certainly suggestive of the protagonism of the T-
lymphocytes in the pathogenesis of emphysema in smokers (Fig. 4). Emphy-
sema was also associated with the presence of increased numbers of alveolar
macrophages, which significantly correlated with the numbers of T-cells,
suggesting an interaction between these cells in the inflammatory process
leading to emphysema, possibly mediated by a T-helper type 1 (Th-1) type
of T-cell response (IFN-g, TNF-a, IL-2 cytotoxine profile).
Abundant but variable numbers of T-cells (CD3 þ ) together with other
inflammatory cells are also found in the small airway of smokers (83). We
studied the inflammatory infiltrates in a series of smokers and nonsmokers
who had airway reactivity measured before undergoing lung resection (84).
Smokers were divided according to the type of emphysema in the lung, CLE,
or PLE. Due to the large variability in the numbers of inflammatory cells in
the airways (from 0 to 500,000 = mm 3 ), no statistical difference was found in
the numbers of the different inflammatory cells in nonsmokers' and smo-
kers' airways. However, the degree of airway reactivity correlated with the
load of T-cells in the airways in smokers with CLE, but not in PLE or non-
smokers. Because similar total numbers of CD3 þ T-cells were present in the
three groups, we suggested that the T-cells in CLE were behaving differently
possibly because they were of a different phenotype (Th-2 vs. Th-1). In
support of this possibility is the finding that Th-2 type cytokines IL-4 and
IL-5 mRNA (cytokines found in asthma) are abundantly expressed by
Figure 4 Correlation between the number of neutrophils (PMN), T-cells (CD3 þ ),
and alveolar macrophages (cells = mm 3 ) in the alveolar wall and emphysema (V V1 alv).
V v alv refers to the density of alveolar wall and was obtained by point counting. The
lower the number, the less the alveolar wall density, and the larger the emphysema.
All the correlations were significant with p < 0.05 or lower. (From Ref. 7.)