TY - JOUR
T1 - Staphylococcus aureus susceptibility to innate antimicrobial peptides, β-defensins and CAP18, expressed by human keratinocytes
AU - Midorikawa, Kazushige
AU - Ouhara, Kazuhisa
AU - Komatsuzawa, Hitoshi
AU - Kawai, Toshihisa
AU - Yamada, Sakuo
AU - Fujiwara, Tamaki
AU - Yamazaki, Kenshi
AU - Sayama, Koji
AU - Taubman, Martin A.
AU - Kurihara, Hidemi
AU - Hashimoto, Koji
AU - Sugai, Motoyuki
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2003/7/1
Y1 - 2003/7/1
N2 - The antimicrobial peptides human β-defensin-1 (hBD1), hBD2, hBD3, and CAP18 expressed by keratinocytes have been implicated in mediation of the innate defense against bacterial infection. To gain insight into Staphylococcus aureus infection, the susceptibility of S. aureus, including methicillin-resistant S. aureus (MRSA), to these antimicrobial peptides was examined. Based on quantitative PCR, expression of hBD2 mRNA by human keratinocytes was significantly induced by contact with S. aureus, and expression of hBD3 and CAP18 mRNA was slightly induced, while hBD1 mRNA was constitutively expressed irrespective of the presence of S. aureus. Ten clinical S. aureus isolates, including five MRSA isolates, induced various levels of expression of hBD2, hBD3, and CAP18 mRNA by human kertinocytes. The activities of hBD3 and CAP18 against S. aureus were found to be greater than those of hBD1 and hBD2. A total of 44 S. aureus clinical isolates, including 22 MRSA strains, were tested for susceptibility to hBD3 and CAP18. Twelve (55%) and 13 (59%) of the MRSA strains exhibited more than 20% survival in the presence of hBD3 (1 μg/ml) and CAP18 (0.5 μg/ml), respectively. However, only three (13%) and two (9%) of the methicillin-sensitive S. aureus isolates exhibited more than 20% survival with hBD3 and CAP18, respectively, suggesting that MRSA is more resistant to these peptides. A synergistic antimicrobial effect between suboptimal doses of methicillin and either hBD3 or CAP18 was observed with 10 MRSA strains. Furthermore, of several genes associated with methicillin resistance, inactivation of the fmtC gene in MRSA strain COL increased susceptibility to the antimicrobial effect mediated by hBD3 or CAP18.
AB - The antimicrobial peptides human β-defensin-1 (hBD1), hBD2, hBD3, and CAP18 expressed by keratinocytes have been implicated in mediation of the innate defense against bacterial infection. To gain insight into Staphylococcus aureus infection, the susceptibility of S. aureus, including methicillin-resistant S. aureus (MRSA), to these antimicrobial peptides was examined. Based on quantitative PCR, expression of hBD2 mRNA by human keratinocytes was significantly induced by contact with S. aureus, and expression of hBD3 and CAP18 mRNA was slightly induced, while hBD1 mRNA was constitutively expressed irrespective of the presence of S. aureus. Ten clinical S. aureus isolates, including five MRSA isolates, induced various levels of expression of hBD2, hBD3, and CAP18 mRNA by human kertinocytes. The activities of hBD3 and CAP18 against S. aureus were found to be greater than those of hBD1 and hBD2. A total of 44 S. aureus clinical isolates, including 22 MRSA strains, were tested for susceptibility to hBD3 and CAP18. Twelve (55%) and 13 (59%) of the MRSA strains exhibited more than 20% survival in the presence of hBD3 (1 μg/ml) and CAP18 (0.5 μg/ml), respectively. However, only three (13%) and two (9%) of the methicillin-sensitive S. aureus isolates exhibited more than 20% survival with hBD3 and CAP18, respectively, suggesting that MRSA is more resistant to these peptides. A synergistic antimicrobial effect between suboptimal doses of methicillin and either hBD3 or CAP18 was observed with 10 MRSA strains. Furthermore, of several genes associated with methicillin resistance, inactivation of the fmtC gene in MRSA strain COL increased susceptibility to the antimicrobial effect mediated by hBD3 or CAP18.
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U2 - 10.1128/IAI.71.7.3730-3739.2003
DO - 10.1128/IAI.71.7.3730-3739.2003
M3 - Article
C2 - 12819054
AN - SCOPUS:0037973517
VL - 71
SP - 3730
EP - 3739
JO - Infection and Immunity
JF - Infection and Immunity
SN - 0019-9567
IS - 7
ER -