Pulmonary infection of cystic fibrosis mice with Staphylococcus aureus requires expression of α-toxin.

Abstract

Pulmonary infections of cystic fibrosis (CF) patients with Staphylococcus aureus (S. aureus) occur very early in the disease. The molecular details that cause infection-susceptibility of CF patients to and mediate infection with S. aureus are poorly characterized. Therefore, we aimed to identify the role of α-toxin, a major S. aureus toxin, for pulmonary infection of CF mice. Infection with S. aureus JE2 resulted in severe pneumonia in CF mice, while wildtype mice were almost unaffected. Deficiency of α-toxin in JE2-Δhla reduced the pathogenicity of S. aureus in CF mice. However, CF mice were still more susceptible to the mutant S. aureus strain than wildtype mice. The S. aureus JE2 induced a marked increase of ceramide and a downregulation of sphingosine and acid ceramidase expression in bronchi of CF mice. Deletion of α-toxin reduced these changes after infection of CF mice. Similar changes were observed in wildtype mice, but at much lower levels. Our data indicate that expression of α-toxin is a major factor causing S. aureus infections in CF mice. Wildtype S. aureus induces a marked increase of ceramide and a reduction of sphingosine and acid ceramidase expression in bronchial epithelial cells of wildtype and CF mice, changes that determine infection susceptibility.

• Authors: Simone Keitsch, Joachim Riethmüller, Matthias Soddemann, Carolin Sehl, Barbara Wilker, Michael J Edwards, Charles C Caldwell, Martin Fraunholz, Erich Gulbins, Katrin Anne Becker
• Journal: Biological chemistry (Biol Chem) Vol. 399 Issue 10 Pg. 1203-1213 (09 25 2018) ISSN: 1437-4315 [Electronic] Germany
• PMID: 29613852 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)

Chemical References

• Bacterial Toxins
• Hemolysin Proteins
• staphylococcal alpha-toxin

Topics

• Animals
• Bacterial Toxins (metabolism)
• Cystic Fibrosis (complications, metabolism, microbiology)
• Female
• Hemolysin Proteins (metabolism)
• Male
• Mice
• Mice, Congenic
• Mice, Inbred C57BL
• Staphylococcal Infections (complications, metabolism, microbiology)
• Staphylococcus aureus (metabolism)