TY - JOUR
T1 - Internalization of Staphylococcus aureus by endothelial cells induces cytokine gene expression
AU - Yao, L.
AU - Bengualid, V.
AU - Lowy, F. D.
AU - Gibbons, J. J.
AU - Hatcher, V. B.
AU - Berman, J. W.
PY - 1995
Y1 - 1995
N2 - The ability of the vascular endothelium to elaborate cytokines in response to gram-positive sepsis has received limited attention. This study examined cytokine expression by human umbilical vein endothelial cells (EC) following infection with a gram-positive bacterial pathogen, Staphylococcus aureus. S. aureus infection of EC resulted in the production of interleukin-6 (IL-6) and IL-1β. For IL-6, message was detected at 3 h after infection, protein was present at 24 h, and both message and protein persisted for 72 h. IL-1β message was detected at 12 h, IL-1β protein was detected at 24 h, and both persisted for 72 h. Message for colony-stimulating factor 1 remained unaltered. UV-killed S. aureus also elicited IL-1β and IL-6 message and protein expression at 24 and 48 h. Twenty-one clinical isolates of S. aureus were tested, and all induced IL-6 release by 48 h. However, the laboratory strain 8325-4 did not induce cytokine expression at any time point and was internalized by EC 1,000-fold less than other strains were. Internalization of latex beads by EC did not induce IL-6 gene expression. Furthermore, cytochalasin D treatment of the EC prevented IL-1 and IL-6 induction by S. aureus but not by tumor necrosis factor alpha or lipopolysaccharide. These results indicate that S. aureus is a potent inducer of IL-1 and IL-6 in EC and that internalization of S. aureus by EC is necessary for their cytokine expression. Thus, our data suggest that the vascular endothelium may play an important role in the pathogenesis of septicemia caused by gram-positive organisms.
AB - The ability of the vascular endothelium to elaborate cytokines in response to gram-positive sepsis has received limited attention. This study examined cytokine expression by human umbilical vein endothelial cells (EC) following infection with a gram-positive bacterial pathogen, Staphylococcus aureus. S. aureus infection of EC resulted in the production of interleukin-6 (IL-6) and IL-1β. For IL-6, message was detected at 3 h after infection, protein was present at 24 h, and both message and protein persisted for 72 h. IL-1β message was detected at 12 h, IL-1β protein was detected at 24 h, and both persisted for 72 h. Message for colony-stimulating factor 1 remained unaltered. UV-killed S. aureus also elicited IL-1β and IL-6 message and protein expression at 24 and 48 h. Twenty-one clinical isolates of S. aureus were tested, and all induced IL-6 release by 48 h. However, the laboratory strain 8325-4 did not induce cytokine expression at any time point and was internalized by EC 1,000-fold less than other strains were. Internalization of latex beads by EC did not induce IL-6 gene expression. Furthermore, cytochalasin D treatment of the EC prevented IL-1 and IL-6 induction by S. aureus but not by tumor necrosis factor alpha or lipopolysaccharide. These results indicate that S. aureus is a potent inducer of IL-1 and IL-6 in EC and that internalization of S. aureus by EC is necessary for their cytokine expression. Thus, our data suggest that the vascular endothelium may play an important role in the pathogenesis of septicemia caused by gram-positive organisms.
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U2 - 10.1128/iai.63.5.1835-1839.1995
DO - 10.1128/iai.63.5.1835-1839.1995
M3 - Article
C2 - 7729892
AN - SCOPUS:0028897616
SN - 0019-9567
VL - 63
SP - 1835
EP - 1839
JO - Infection and immunity
JF - Infection and immunity
IS - 5
ER -