Blockade of CD137 signaling counteracts polymicrobial sepsis induced by cecal ligation and puncture.
Sepsis, a leading cause of death worldwide, involves proinflammatory responses and inefficient bacterial clearance. Previously, we have shown that CD137 (4-1BB), a member of the tumor necrosis factor receptor superfamily, plays critical roles in eradicating infective Listeria monocytogenes, a gram-positive bacterium, and that stimulation of CD137 protects mice from sepsis-induced death. In this study, we unexpectedly found that CD137 activation aggravated polymicrobial sepsis due to mixed gram-positive and gram-negative bacterial infection induced by cecal ligation and puncture (CLP). CD137-deficient (CD137(-/-)) mice showed significantly lower mortality than CD137-sufficient (CD137(+/+)) mice in the CLP model. Administration of an agonistic anti-CD137 monoclonal antibody (MAb) to CD137(+/+) mice decreased their survival in this infection model, while administration of a blocking anti-CD137 ligand MAb (TKS-1) to such mice increased their survival. CD137(-/-) mice and TKS-1-treated CD137(+/+) mice had lower levels of chemokines/proinflammatory cytokines (monocyte chemoattractant protein 1, interleukin-6 [IL-6], tumor necrosis factor alpha, IL-12) and an anti-inflammatory cytokine (IL-10), exhibited improved bacterial clearance in the peritoneum, liver, and blood, and had greater numbers of infiltrated peritoneal neutrophils and macrophages in the CLP model than control mice. Our data suggest that CD137 activation aggravates polymicrobial sepsis induced by CLP.
Nguyen
Quang-Tam
QT
Department of Biological Sciences, Life Sciences Research Center, University of Ulsan, Ulsan 680-749, Korea.
Ju
Seong-A
SA
Park
Sang-Min
SM
Lee
Sang-Chul
SC
Yagita
Hideo
H
Lee
In Hee
IH
Kim
Byung-Sam
BS
D000818:Animals; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D002432:Cecum; D002465:Cell Movement; D007962:Leukocytes / Q000502:physiology; D008026:Ligation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D011677:Punctures; D018805:Sepsis / Q000382:microbiology / Q000517:prevention & control*; D015398:Signal Transduction / Q000502:physiology*; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9 / Q000037:antagonists & inhibitors* / Q000502:physiology
D000911:Antibodies, Monoclonal; D053261:Tumor Necrosis Factor Receptor Superfamily, Member 9