Korean J Parasitol.  2008 Sep;46(3):145-151. 10.3347/kjp.2008.46.3.145.

Suppressed Production of Pro-inflammatory Cytokines by LPS-Activated Macrophages after Treatment with Toxoplasma gondii Lysate

• Lee EJ
• Heo YM
• Choi JH
• Song HO
• Ryu JS
• Ahn MH

• KMID: 1720557
• DOI: http://doi.org/10.3347/kjp.2008.46.3.145

Abstract

During Toxoplasma gondii infection, macrophages, dendritic cells, and neutrophils are important sources of pro-inflammatory cytokines from the host. To counteract the pro-inflammatory activities, T. gondii is known to have several mechanisms inducing down-regulation of the host immunity. In the present study, we analyzed the production of proand anti-inflammatory cytokines from a human myelomonocytic cell line, THP-1 cells, in response to treatment with T. gondii lysate or lipopolysaccharide (LPS). Treatment of THP-1 cells with LPS induced production of IL-12, TNF-alpha, IL-8, and IL-10. Co-treatment of THP-1 cells with T. gondii lysate inhibited the LPS-induced IL-12, IL-8 and TNF-alpha expression, but increased the level of IL-10 synergistically. IL-12 and IL-10 production was down-regulated by anti-human toll-like receptor (TLR)-2 and TLR4 antibodies. T. gondii lysate triggered nuclear factor (NF)-kappaB-dependent IL-8 expression in HEK293 cells transfected with TLR2. It is suggested that immunosuppression induced by T. gondii lysate treatment might occur via TLR2-mediated NF-kappaB activation.

Keyword

Toxoplasma gondii; LPS; macrophage; cytokine; toll-like receptor; NF-kappaB

MeSH Terms

Animals
Cell Line
Cytokines/*biosynthesis
Humans
Inflammation/metabolism
Lipopolysaccharides/*pharmacology
Macrophages/*drug effects/*metabolism
Toxoplasma