High concentrations of alpha-defensins in plasma and bronchoalveolar lavage fluid of patients with acute respiratory distress syndrome.

Abstract

alpha-Defensins, antimicrobial peptides localized in neutrophils, participate in tissue damage through their cytotoxic effects in neutrophil-mediated pulmonary diseases. Neutrophils play an important role in the pathogenesis of acute respiratory distress syndrome (ARDS). We measured alpha-defensins levels in plasma and bronchoalveolar lavage fluid (BALF) of ARDS patients to assess the kinetics of alpha-defensins in ARDS. Plasma alpha-defensins levels were higher in ARDS patients than in control subjects, and BALF levels were also higher in ARDS patients than in control subjects. In ARDS, BALF alpha-defensins levels correlated with those of interleukin (IL)-8, and plasma alpha-defensins levels also correlated with Lung Injury Score. Peripheral neutrophil alpha-defensins contents were higher in ARDS than the control. IL-8 dose-dependently stimulated alpha-defensins release from cultured neutrophils and these levels were higher in ARDS than the control. Reverse-phase high performance liquid chromatography showed high plasma levels of pro-defensins, precursors of alpha-defensins from the bone marrow in ARDS, although alpha-defensins in peripheral and BALF neutrophils were mature type. In conclusion, high plasma alpha-defensins in ARDS patients result from the release of pro-defensins from bone marrow, rather than mature alpha-defensins from neutrophils that accumulate in the alveolar space. The alpha-defensins contents of peripheral neutrophils in ARDS are higher and easier to release than control.

• Authors: Jun-Ichi Ashitani, Hiroshi Mukae, Yasuji Arimura, Arisa Sano, Masatoshi Tokojima, Masamitsu Nakazato
• Journal: Life sciences (Life Sci) Vol. 75 Issue 9 Pg. 1123-34 (Jul 16 2004) ISSN: 0024-3205 [Print] Netherlands
• PMID: 15207659 (Publication Type: Comparative Study, Journal Article)
• Copyright: Copyright 2004 Elsevier Inc.

Chemical References

• Interleukin-8
• alpha-Defensins
• Granulocyte Colony-Stimulating Factor

Topics

• Aged
• Bone Marrow (metabolism)
• Bronchoalveolar Lavage Fluid (chemistry)
• Chromatography, High Pressure Liquid
• Enzyme-Linked Immunosorbent Assay
• Female
• Granulocyte Colony-Stimulating Factor (metabolism)
• Humans
• Interleukin-8 (blood)
• Kinetics
• Lung Injury
• Male
• Middle Aged
• Neutrophils (metabolism)
• Respiratory Distress Syndrome (blood, metabolism)
• alpha-Defensins (blood)