Thursday, December 03, 2009

IL-33 receptor (T1/ST2) signalling is necessary to prevent the development of encephalitis in mice infected with Toxoplasma gondii

Eur J Immunol. 2009 Nov 30. [Epub ahead of print]

IL-33 receptor (T1/ST2) signalling is necessary to prevent the development of encephalitis in mice infected with Toxoplasma gondii

Jones LA, Roberts F, Nickdel MB, Brombacher F, McKenzie AN, Henriquez FL, Alexander J, Roberts CW.

Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK.

T1/ST2 is an immunoregulatory protein of the IL-1 receptor (IL-1R) family that has recently been reported as being a component of the IL-33 receptor (IL-33R). IL-33 is a newly described cytokine known to amplify the Th2 response and reduce production of Th1 cytokines. The function of T1/ST2 during Toxoplasma gondii infection is as yet undescribed. Given the requirement of a balanced type 1/type2 response for effective control of parasite number and immunopathology, it is likely that T1/ST2 may play a part in aiding this process. Accordingly, we have shown that T1/ST2 mRNA transcripts are upregulated in the brains of mice infected with T. gondii and that mice deficient in T1/ST2 demonstrated increased susceptibility to infection with T. gondiithat correlated with increased pathology and greater parasite burden in the brains. Real time PCR analysis of cerebral cytokine levels revealed increased mRNA levels of iNOS, IFN-gamma and TNF-alpha in infected T1/ST2-/- mice. These effects were independent of changes in IL-10 production. This study provides the first evidence of a specific role for IL-33 receptor signaling in the brain as well as highlighting the requirement of this mechanism in limiting infection with an intracellular parasite.

PMID: 19950183 [PubMed - as supplied by publisher]