Epithelial Neutrophil-Activating Peptide-78 Recruits Neutrophils into Pleural Effusion

¹ Institute of Respiratory Diseases, First Affiliated Hospital, Guangxi Medical University, Nanning 530021, Guangxi, People's Republic of China
² Dept of Respiratory Disease, Second Hospital of Medical School of Zhejiang University, Hangzhou 310009, Zhejiang, People's Republic of China

^* To whom correspondence should be addressed. E-mail: shihuanzhong{at}sina.com.

	Abstract

The aim of this study was to investigate the presence of epithelial neutrophil-activating peptide (ENA)-78 in pleural effusions, as well as the chemoattractant activity of pleural ENA-78 on neutrophils.

Pleural effusion and serum samples were collected from 75 patients who presented to the respiratory institute (19 with malignant pleural effusion, 21 with tuberculous pleural effusion, 18 with infectious pleural effusion, and 17 with transudative pleural effusion). The concentrations of ENA-78, myeloperoxidase and neutrophil elastase were determined, and the chemoattractant activity of ENA-78 for neutrophils both in vitro and in vivo was also observed.

The concentrations of ENA-78, myeloperoxidase and neutrophil elastase in infectious pleural effusion were significantly higher than those in malignant, tuberculous, and transudative groups, respectively (all p<0.01). Infectious pleural fluid was chemotactic for neutrophils in vitro, and anti-ENA-78 antibody could inhibited partly this chemotactic effects. Intrapleural administration of ENA-78 produced a marked progressive influx of neutrophils into pleural space.

Compared to non-infectious pleural effusion, ENA-78 appeared to be increased in infectious pleural effusion. Our data suggested that ENA-78 was able to induce neutrophil infiltration into pleural space, and might be responsible for pleural neutrophil degranulation.