Interleukin-8 production by human airway epithelial cells in response to Pseudomonas aeruginosa clinical isolates expressing type a or type b flagellins.
Pseudomonas aeruginosa lung infection is a major cause of morbidity and mortality worldwide. P. aeruginosa flagellin, the main structural protein of the flagellar filament, is a virulence factor with proinflammatory activity on respiratory epithelial cells. P. aeruginosa bacteria express one of two isoforms of flagellin (type a or b) that differ in their primary amino acid sequences as well as in posttranslational glycosylation. In this study, the distribution of type a and b flagellins among 3 P. aeruginosa laboratory strains and 14 clinical isolates (1 ulcerative keratitis, 3 cystic fibrosis, and 10 acute pneumonia isolates) was determined, and their abilities to stimulate interleukin-8 (IL-8) production by human airway epithelial cells was compared. By comparison with the PAK (type a) and PAO1 (type b) prototype laboratory strains, 10/14 (71.4%) of clinical isolates expressed type a and 4/14 (28.6%) expressed type b flagellins. Among four cell lines surveyed, BEAS-2B cells were found to give the greatest difference between constitutive and flagellin-stimulated IL-8 production. All 17 flagellins stimulated IL-8 production by BEAS-2B cells (range, 700 to 4,000 pg/ml). However, no discernible differences in IL-8 production were evident when comparing type a versus type b flagellins or flagellins from laboratory versus clinical strains or among the clinical strains.
Shanks
Kathleen K
KK
Division of Pulmonology/Allergy, Department of Pediatrics, University of Maryland School of Medicine, 655 W. Baltimore Street, Baltimore, MD 21201, USA.
Guang
Wei
W
Kim
K Chul
KC
Lillehoj
Erik P
EP
D002460:Cell Line; D004847:Epithelial Cells / Q000276:immunology*; D005408:Flagellin / Q000096:biosynthesis* / Q000145:classification / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D016209:Interleukin-8 / Q000378:metabolism*; D020033:Protein Isoforms / Q000276:immunology; D011550:Pseudomonas aeruginosa / Q000276:immunology*; D020545:Respiratory Mucosa / Q000276:immunology
C508606:CXCL8 protein, human; D016209:Interleukin-8; D020033:Protein Isoforms; D005408:Flagellin