Lipoteichoic acid from Staphylococcus aureus induced expression of MMP-9 in human middle ear epithelial cells.
OBJECTIVE
Change in matrix metalloproteinases (MMPs) and regulation of their tissue inhibitors of metalloproteinases (TIMPs) could play certain role in the pathogenesis of otitis media. This study was designed to evaluate the modulation of MMPs and TIMPs in middle ear epithelium by lipoteichoic acid (LTA) isolated from Staphylococcus aureus.


METHODS
Human middle ear epithelial (HMEE) cells were treated with LTA. MMP activities were examined by PCR, ELISA and zymography, and levels of TIMPs were measured by PCR and ELISA.


RESULTS
LTA isolated from S. aureus increased MMP-9 mRNA expression and secretion in HMEE cells, whereas no effect on the expressions of MMP-1, -2, -3, -7 and TIMP-1, -2 was observed.


CONCLUSIONS
LTA increased the activity of MMP-9, not TIMPs in middle ear epithelia, suggesting that disturbed balance between MMP-9 and TIMPs could play an active role in LTA-induced otitis media.
Department of Otolaryngology, Ajou University School of Medicine, Suwon, Republic of Korea.
Hun Yi
HY
Park
Jung-Whan
JW
Song
Sung Pyo
SP
Hong
Seung Min
SM
In
Hyun Jun
HJ
Kim
D018929:Cell Culture Techniques; D004432:Ear, Middle / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D004847:Epithelial Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D010033:Otitis Media / Q000209:etiology; D013211:Staphylococcus aureus; D013682:Teichoic Acids / Q000494:pharmacology*; D019714:Tissue Inhibitor of Metalloproteinases / Q000378:metabolism*
D008070:Lipopolysaccharides; D013682:Teichoic Acids; D019714:Tissue Inhibitor of Metalloproteinases; C009900:lipoteichoic acid; D020780:Matrix Metalloproteinase 9