Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2006-6-5
pubmed:abstractText
The Jak, Tyk2, is activated in response to IL-12 and IFN-alphabeta and promotes IFN-gamma production by Th1-type CD4 cells. Mice deficient in Tyk2 function have been previously shown to be resistant to autoimmune arthritis and septic shock but are acutely susceptible to opportunistic pathogens such as Toxoplasma gondii. In this study, we show that Tyk2, in addition to mediating the biological effects of IL-12 and IFN-alphabeta, is an important regulator for the signaling and expression of the immunosuppressive cytokine IL-10. In the absence of Tyk2, Ag-reactive CD4 cells exhibit impaired IL-10 synthesis following rechallenge of T. gondii vaccine-primed mice. The impaired IL-10 reactivation leads to unopposed antimicrobial effector mechanisms which results in a paradoxically superior protection of immune Tyk2(-/-) mice against virulent T. gondii challenge. We further demonstrate that Tyk2 indirectly controls CD4 IL-10 reactivation by signaling for maximal IFN-gamma secretion. The unexpected role of IFN-gamma in mediating IL-10 reactivation by Th1 cells provides compelling evidence that conditions driving Th1 responses establish a negative feedback loop, which will ultimately lead to its autoregulation. Thus, Tyk2 can be viewed as a dual-function Jak, mediating both pro and anti-inflammatory cytokine responses.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
176
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7263-71
pubmed:dateRevised
2011-2-16
pubmed:meshHeading
pubmed-meshheading:16751369-Animals, pubmed-meshheading:16751369-Antigens, CD4, pubmed-meshheading:16751369-Ascitic Fluid, pubmed-meshheading:16751369-Cells, Cultured, pubmed-meshheading:16751369-Dose-Response Relationship, Immunologic, pubmed-meshheading:16751369-Down-Regulation, pubmed-meshheading:16751369-Genetic Predisposition to Disease, pubmed-meshheading:16751369-Immunity, Cellular, pubmed-meshheading:16751369-Interferon-gamma, pubmed-meshheading:16751369-Interleukin-10, pubmed-meshheading:16751369-Interleukin-12, pubmed-meshheading:16751369-Interleukin-12 Subunit p35, pubmed-meshheading:16751369-Mice, pubmed-meshheading:16751369-Mice, Inbred C57BL, pubmed-meshheading:16751369-Mice, Knockout, pubmed-meshheading:16751369-Protein Subunits, pubmed-meshheading:16751369-Protein-Tyrosine Kinases, pubmed-meshheading:16751369-Signal Transduction, pubmed-meshheading:16751369-TYK2 Kinase, pubmed-meshheading:16751369-Th1 Cells, pubmed-meshheading:16751369-Toxoplasma, pubmed-meshheading:16751369-Toxoplasmosis
pubmed:year
2006
pubmed:articleTitle
Tyk2 negatively regulates adaptive Th1 immunity by mediating IL-10 signaling and promoting IFN-gamma-dependent IL-10 reactivation.
pubmed:affiliation
Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural