Send to

Choose Destination
Microb Pathog. 2004 Jul;37(1):11-9.

Lipid raft microdomains mediate class A scavenger receptor-dependent infection of Brucella abortus.

Author information

Department of Applied Veterinary Science, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro-shi, Hokkaido 080-8555, Japan.


Brucella abortus is a facultative intracellular bacterium that can survive inside macrophages. Intracellular replication of B. abortus requires the VirB complex, which is highly similar to the conjugative DNA transfer system. In this study, we showed that a class A scavenger receptor (SR-A) of macrophages is required to internalize B. abortus and contributes to the establishment of bacterial infection in mice. Macrophages from SR-A-deficient mice inhibited internalization and intracellular replication of both wild type strain and the virB4 mutant, and that bacterial proliferation was inhibited in SR-A-deficient mice. Adding lipopolysaccharide from B. abortus and Salmonella enterica serovar Typhimurium, but not from Escherichia coli, to macrophages inhibited bacterial internalization. VirB-dependent bacterial internalization induced localization of SR-A into detergent-resistant membrane lipid rafts. These results indicate that B. abortus internalizes into macrophages by using SR-A as a receptor and that the VirB type IV secretion system of B. abortus regulates signal transduction dependent on SR-A to form replicative phagosomes, and which is mediated by lipid rafts.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center