[Airway alveolar macrophages and LFA-1 expression in chronic bronchitis]

To assess the relationship between the expressions of lymphocyte function associated antigen-1 (LFA-1) in macrophages in both BALF and bronchial mucosa and the severity of airway inflammation in patients of chronic bronchitis.

Bronchial alveolar lavage and bronchial mucosa biopsy were performed in 18 patients with stable stage of chronic bronchitis (CB). LFA-1 positive alveolar macrophage (AM) was measured by immunocytochemistry stain. The percentages and number of AM in BALF and bronchial mucosa were also calculated and the thickness of mucosa measured.

(1) The numbers of AM and neutrophils of BALF in CB were significantly higher than those in healthy group (P < 0.01, respectively). So did the percentage of neutrophils of BALF (all P < 0.05). (2) The number [(4.36 +/- 2.11) x 10(4)/ml] and percentage [(24.6 +/- 5.8)%] of positive AM expressing LFA-1 in CB were significantly higher than those [(0.63 +/- 0.25) x 10(4)/ml, (10.6 +/- 2.7)%] in healthy group (all P < 0.01, respectively). The number of AM in BALF was positively correlated with that of positive AM expressing LFA-1 (r = 0.624 7, P < 0.01). The number of CD(68)(+) cells [(21.6 +/- 4.6)/HP] in mucosa and the thickness of mucosa [(0.20 +/- 0.09) micrometer] in CB were significantly greater than those [(10.0 +/- 3.4)/HP, (0.08 +/- 0.04) micrometer] in healthy group (P < 0.01, respectively). They were inversely corrlated with the value of FEV(1)%pre (r = -0.5875, P < 0.01; r = -0.655, P < 0.05).

Increased expression of LFA-1 may be one of important causes leading to the accumulation and migration of AM in the airway of patient with CB. AM infiltration and the thickening of bronchial mucosa are closely related to the decline of FEV(1).