HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Deletion of scavenger receptor A gene in mice resulted in protection from septic shock and modulation of TLR4 signaling in isolated peritoneal macrophages.

Abstract
Scavenger receptor A (Sra), also known as macrophage scavenger receptor 1 (Msr1), is a surface glycoprotein preferentially present in macrophages that plays a primary role in innate immunity. Previous studies have shown that Sra is a modifier gene for the response to bacterial LPS in mice at the level of IL-10 production, in particular. In the present study, we found that Sra(-/-) mice are more resistant to septic shock induced by cecal ligation and puncture than wild-type C57BL/6 J (B6) mice. In addition, Sra(-/-) mice displayed initial elevated high density lipoprotein (HDL) circulating levels. Naïve peritoneal macrophages (PMs) were isolated from Sra(-/-) mice to understand the possible protective mechanism. Incubation of these cells with LPS was found to modulate TLR4 signaling, leading to a reduction in IL-10 and IL-6 mRNA levels, but not TNF-α expression, at low concentrations of LPS in comparison with PMs isolated from B6 mice. No differences were found in LPS binding between PMs derived from Sra(-/-) or B6 mice. The lack of Sra binding to LPS was confirmed after transfection of Chinese hamster ovary (CHO) cells with the Sra gene. The contribution of Sra to the outcome of sepsis may be a combination of changes in TLR4 signaling pathway and elevated levels of HDL in circulation, but also LPS toxicity.
AuthorsRobert Drummond, David M Cauvi, Dennis Hawisher, Donghuan Song, Diego F Niño, Raul Coimbra, Stephen Bickler, Antonio De Maio
JournalInnate immunity (Innate Immun) Vol. 19 Issue 1 Pg. 30-41 (Feb 2013) ISSN: 1753-4267 [Electronic] United States
PMID22751446 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
Chemical References
  • Cytokines
  • Lipopolysaccharides
  • Scavenger Receptors, Class A
  • Toll-Like Receptor 4
Topics
  • Animals
  • CHO Cells
  • Cricetinae
  • Cytokines (metabolism)
  • Lipopolysaccharides (immunology)
  • Macrophages, Peritoneal (immunology)
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Scavenger Receptors, Class A (genetics, metabolism)
  • Shock, Septic (genetics, immunology)
  • Signal Transduction (genetics, immunology)
  • Toll-Like Receptor 4 (metabolism)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: