Nishimaki K, Okuyama K, Okada S, Hattori T, Takayanagi M, Ohno I. Prolongation of neutrophil survival by the culture supernatant of Pseudomonas aeruginosa.
Respirology 2007;
12:664-9. [PMID:
17875053 DOI:
10.1111/j.1440-1843.2007.01131.x]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVES
The pathogenesis of airway inflammation in diffuse panbronchiolitis (DPB) is unknown. Neutrophil survival-enhancing activity, partially mediated by granulocyte-macrophage colony-stimulating factor (GM-CSF), has been shown in the sputum from DPB patients. This study investigated the mechanisms of GM-CSF expression in the airways of DPB patients. This involved examining the effects of mucoid Pseudomonas aeruginosa strains derived from chronically colonized patients with DPB on neutrophil survival and GM-CSF expression.
METHODS
Neutrophils from healthy subjects were cultured with the culture supernatants of P. aeruginosa isolated from sputum of DPB patients in the presence or absence of anti-GM-CSF and anti-GM-CSF receptor (alpha chain) antibodies, and viable neutrophils were counted daily. GM-CSF gene expression in neutrophils was evaluated by RT-PCR.
RESULTS
Neutrophils cultured with the culture supernatants showed significantly prolonged survival, compared with neutrophils cultured with the control broth. The neutrophil survival-enhancing activity in the culture supernatants was lost by heating. The enhanced survival of neutrophils was abolished in the presence of anti-GM-CSF and anti-GM-CSF receptor (alpha chain) antibodies. GM-CSF mRNA was detected in neutrophils cultured with the bacterial supernatants, but not in those with the control broth.
CONCLUSION
P. aeruginosa-derived factors (rich in proteins) stimulated neutrophils to synthesize GM-CSF, which enhanced neutrophil survival in an autocrine/paracrine fashion.
Collapse