Effects of alpha-toxin of Staphylococcus aureus on the ciliary activity and ultrastructure of human nasal ciliated epithelial cells.
OBJECTIVE
The in vitro effects of staphylococcal alpha-toxin on ciliary activity were investigated at different concentrations and exposure times.


METHODS
Ciliated epithelial cells of the sphenoid sinus were taken from patients operated on for pituitary tumors. Video-computerized analysis technique and transmission electron microscopy were used to analyze the effects of the toxin on ciliary activity.


METHODS
Ciliary beat frequency (CBF) was measured in four different concentrations of alpha-toxin including 0.1, 1, 10, and 50 microg/mL. CBF was measured at 2, 4, 6, 12, 24, and 48 hours after administration of the toxin. To observe reversibility of the reduced ciliary activity, after 24-hour incubation in the media containing 10 microg/mL of alpha-toxin, the media were replaced with alpha-toxin-free media. The tissues were also processed for transmission electron microscopy to observe ultrastructural changes of the epithelial cells.


RESULTS
CBF increased significantly at 2-hour incubation and then decreased significantly after 12-hour incubation in 10 microg/mL of alpha-toxin (P< .05, repeated-measures ANOVA). The transmission electron microscopic findings showed mitochondrial swelling and a slight protrusion of the plasma membrane of the cilia. In toxin-free media, loss of ciliary activity was not recovered.


CONCLUSIONS
CBF increased at first, but with increasing incubation time ciliary movements decreased gradually and stopped eventually. This loss of CBF may be an irreversible change associated with ultrastructural changes in the mitochondria and the plasma membrane of the cilia.
Yun
Y S
YS
Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Inha University, Inchon, Korea.
Min
Y G
YG
Rhee
C S
CS
Jung
I H
IH
Koh
Y Y
YY
Jang
T Y
TY
Jung
D H
DH
D001427:Bacterial Toxins / Q000494:pharmacology*; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects* / Q000473:pathology; D006460:Hemolysin Proteins / Q000494:pharmacology*; D006801:Humans; D008854:Microscopy, Electron; D009079:Mucociliary Clearance / Q000187:drug effects*; D009297:Nasal Mucosa / Q000187:drug effects* / Q000473:pathology; D013211:Staphylococcus aureus / Q000472:pathogenicity*
D001427:Bacterial Toxins; D006460:Hemolysin Proteins; C021091:staphylococcal alpha-toxin