title: Characterization of Staphylococcus aureus isolates from pediatric patients with cystic fibrosis.
abstract: Staphylococcus aureus is one of the major respiratory pathogens associated with cystic fibrosis (CF) patients. In this study, we collected sputum and isolated fifty S. aureus isolates from CF patients with the median age of 9.5 years old. Then we determined the profiles of these isolates by antibiotic susceptibility testing, examining their cytotoxicity and ability to internalize into an epithelial cell line (A549), as well as multiple loci sequencing typing. Predominant CF S. aureus isolates were resistant to penicillin; however, these isolates were sensitive to various antibiotics, such as vancomycin and minocycline. Different CF S. aureus isolates showed distinct cytotoxic activities, and 90 % of CF S. aureus isolates possessed the enterotoxin genes, sea and hlg. Moreover, we found that multiple different CF S. aureus isolates appeared to have the distinct capacity of invading A549 cells. ST5 (14 %), ST30 (14 %), and ST8 (10 %) were prevalent ST types in these isolates. Further analysis revealed that ST5 and ST30 isolates were less toxic than ST8 and ST15 isolates, and that the ST5, ST15, ST59, and ST87 types of CF S. aureus were less capable of invading A549 cells. Our results suggest that the ST typing method may be useful in predicting cytotoxicity and the invading capacity of S. aureus isolates from patients with CF.
authors: Shanghai Vocational College of Agriculture and Forestry , Shanghai, China.|University of Minnesota, 1971 Commonwealth Ave., St. Paul, MN, 55108, USA.
authors: Ying
authors: Y
authors: Liu
authors: Shanghai Vocational College of Agriculture and Forestry , Shanghai, China.
authors: Jiang
authors: J
authors: Zhang
authors: Shanghai Vocational College of Agriculture and Forestry , Shanghai, China.|University of Minnesota, 1971 Commonwealth Ave., St. Paul, MN, 55108, USA.
authors: Dengke
authors: D
authors: Zhong
authors: Mayo Clinic, Rochester, MN, USA.|University of Minnesota, Minneapolis, MN, 55455, USA.
authors: Lu
authors: L
authors: Ji
authors: University of Minnesota, 1971 Commonwealth Ave., St. Paul, MN, 55108, USA.
authors: Junshu
authors: J
authors: Yang
authors: Mayo Clinic, Rochester, MN, USA. James.R.Phillips@gunet.georgetown.edu.|Georgetown University, 3800 Reservoir Rd, NW, Washington, DC, 200007, USA. James.R.Phillips@gunet.georgetown.edu.
authors: James
authors: J
authors: Phillips
authors: University of Minnesota, 1971 Commonwealth Ave., St. Paul, MN, 55108, USA. jixxx002@umn.edu.
authors: Yinduo
authors: http://orcid.org/0000-0002-0199-0195
authors: Y
authors: Ji
mesh_terms: D000072283:A549 Cells; D002470:Cell Survival; D002648:Child; D003550:Cystic Fibrosis / Q000382:microbiology*; D004768:Enterotoxins / Q000235:genetics; D006801:Humans; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing / Q000379:methods*; D010403:Penicillin Resistance; D010802:Phylogeny; D013183:Sputum / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D004768:Enterotoxins
keywords: Cystic fibrosis; Cytotoxicity; Invasion; MLST; Staphylococcus aureus