|
|
||||||||
INFLAMMATION/IMMUNITY/MEDIATORS
The Laboratory of Trauma, Sepsis & Inflammation Research, Department of Surgery, University of Cincinnati, Cincinnati, Ohio
Submitted 17 May 2005 ; accepted in final form 1 July 2005
Hepatic ischemia-reperfusion results in an acute inflammatory response culminating in the recruitment of activated neutrophils that directly injure hepatocytes. Recent evidence suggests that CD4+ lymphocytes may regulate this neutrophil-dependent injury, but the mechanisms by which this occurs remain to be elucidated. In the present study, we sought to determine the type of CD4+ lymphocytes recruited to the liver after ischemia-reperfusion and the manner in which these cells regulated neutrophil recruitment and tissue injury. Wild-type and CD4 knockout (CD4/) mice were subjected to hepatic ischemia-reperfusion. CD4+ lymphocytes were recruited in the liver within 1 h of reperfusion and remained for at least 4 h. These cells were comprised of conventional (
TCR-expressing), unconventional (
TCR-expressing), and natural killer T cells. CD4/ mice were then used to determine the functional role of CD4+ lymphocytes in hepatic ischemia-reperfusion injury. Compared with wild-type mice, CD4/ mice had significantly greater liver injury, yet far less neutrophil accumulation. Adoptive transfer of CD4+ lymphocytes to CD4/ mice recapitulated the wild-type response. In wild-type mice, neutralization of interleukin (IL)-17, a cytokine released by activated CD4+ lymphocytes, significantly reduced neutrophil recruitment in association with suppression of MIP-2 expression. Finally, oxidative burst activity of liver-recruited neutrophils was higher in CD4/ mice compared with those from wild-type mice. These data suggest that CD4+ lymphocytes are rapidly recruited to the liver after ischemia-reperfusion and facilitate subsequent neutrophil recruitment via an IL-17-dependent mechanism. However, these cells also appear to attenuate neutrophil activation. Thus the data suggest that CD4+ lymphocytes have dual, opposing roles in the hepatic inflammatory response to ischemia-reperfusion.
liver injury; cell trafficking; neutrophils; T cells; interleukin-17
This article has been cited by other articles:
![]() |
C. C. Caldwell, J. Tschoep, and A. B. Lentsch Lymphocyte function during hepatic ischemia/reperfusion injury J. Leukoc. Biol., September 1, 2007; 82(3): 457 - 464. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Hasegawa, Y. Ito, J. Wijeweera, J. Liu, E. Malle, A. Farhood, R. S. McCuskey, and H. Jaeschke Reduced inflammatory response and increased microcirculatory disturbances during hepatic ischemia-reperfusion injury in steatotic livers of ob/ob mice Am J Physiol Gastrointest Liver Physiol, May 1, 2007; 292(5): G1385 - G1395. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Brand, J. Dambacher, F. Beigel, K. Zitzmann, M. H. J. Heeg, T. S. Weiss, T. Prufer, T. Olszak, C. J. Steib, M. Storr, et al. IL-22-mediated liver cell regeneration is abrogated by SOCS-1/3 overexpression in vitro Am J Physiol Gastrointest Liver Physiol, April 1, 2007; 292(4): G1019 - G1028. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |