Yersinia pestis and host macrophages: immunodeficiency of mouse macrophages induced by YscW
AUTOR(ES)
Bi, Yujing
FONTE
Blackwell Science Inc
RESUMO
The virulence of the pathogenic Yersinia species depends on a plasmid-encoded type III secretion system (T3SS) that transfers six Yersinia outer protein (Yop) effector proteins into the cytoplasm of eukaryotic cells, leading to disruption of host defence mechanisms. It is shown in this study that Yersinia pestis YscW, a protein of the T3SS injectisome, contributes to the induction of a deficiency in phagocytosis in host macrophages and a reduction in their antigen-presenting capacity. A Y. pestis strain lacking yscW had no effect on uptake by host macrophages. In mice infected with wild-type Y. pestis, the yscW mutant or a complement strain, immunodeficiency was observed in host macrophages compared with those from uninfected mice. However, the phagocytosis and antigen presenting capacities of macrophages infected by yscW mutant strain both in vivo and in vitro were significantly higher than those by wild type strain. Consistent with this finding, when YscW was expressed in the RAW264·7 macrophage cell line, phagocytosis and antigen-presenting capacities were significantly lower than those of the control groups. These results indicate that Y. pestis YscW may directly induce immunodeficiency in murine macrophages by crippling their phagocytosis and antigen-presenting capacities. These data provide evidences to Y. pestis pathogenesis that some proteins in T3SS injectisome, such as YscW protein, might play independent roles in disrupting host defense apart from their known functions.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2753946Documentos Relacionados
- Role of the Pilot Protein YscW in the Biogenesis of the YscC Secretin in Yersinia enterocolitica
- Structure and regulation of the Yersinia pestis yscBCDEF operon.
- Yersinia pestis grows within phagolysosomes in mouse peritoneal macrophages.
- Mutations in yscC, yscD, and yscG prevent high-level expression and secretion of V antigen and Yops in Yersinia pestis.
- Growth in mouse peritoneal macrophages of Yersinia pestis lacking established virulence determinants.