[Elastase activity in bronchoalveolar lavage fluid from patients with diffuse panbronchiolitis].
The clinical and pathological features of diffuse panbronchiolitis (DPB) have been well reported to date though its pathogenesis remains unknown. This study was designed to evaluate the protease antiprotease imbalance in patients with DPB. For this purpose, we performed bronchoalveolar lavage (BAL) in sixteen patients with DPB, twelve patients with chronic bronchitis (CB) and control subjects (nine smokers and eleven non-smokers), and determined elastase activity and alpha 1 antitrypsin (alpha 1 AT) concentration in bronchoalveolar lavage fluid (BALF). Elastase activity was measured using a synthetic substrate, succinyl-tri-L-alanine-p-nitroanilide. BALF from eleven of sixteen patients with DPB showed elastase activity. However, only two of twelve patients with CB showed elastase activity, and control subjects did not show any elastase activity in BALF. Although alpha 1 AT concentration is elevated in BALF from patients with DPB, it is assumed that elastase burden exceeded the elastase inhibitory capacity of alpha 1 AT in BALF. The percentage of neutrophils in BALF correlated significantly with elastase activity which was inhibited by DFP, but not by EDTA. These data revealed that the elastase in BALF was a serine protease of neutrophil origin. In five DPB-patients treated with low-dose long-term erythromycin chemotherapy, elastase activity in BALF decreased significantly. The above mentioned findings suggest that the neutrophil elastase plays an important role in the pathogenesis of DPB, and the mode of action of erythromycin on DPB is to decrease the elastase burden.
First Department of Internal Medicine, Kurume University, Japan.
H
H
Ninomiya
Y
Y
Ichikawa
H
H
Koga
T
T
Yano
K
K
Oizumi
D000293:Adolescent; D000328:Adult; D000368:Aged; D000418:Albumins / Q000032:analysis; D001988:Bronchiolitis / Q000201:enzymology*; D001991:Bronchitis / Q000201:enzymology; D001992:Bronchoalveolar Lavage Fluid / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000201:enzymology; D010196:Pancreatic Elastase / Q000032:analysis*; D012907:Smoking / Q000378:metabolism; D000515:alpha 1-Antitrypsin / Q000032:analysis
D000418:Albumins; D000515:alpha 1-Antitrypsin; D010196:Pancreatic Elastase