Article

Precarious Balance: Th17 Cells in Host Defense

Department of Pediatrics, Division of Immunology and Transplantation Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
Infection and immunity (Impact Factor: 3.73). 11/2009; 78(1):32-8. DOI: 10.1128/IAI.00929-09
Source: PubMed

ABSTRACT

Lineage-specific responses from the effector T-cell repertoire form a critical component of adaptive immunity. The recent
identification of Th17 cells—a third, distinct lineage of helper T cells—collapses the long-accepted paradigm in which Th1
and Th2 cells distinctly mediate cellular and humoral immunity, respectively. In this minireview, we discuss the involvement
of the Th17 lineage during infection by extracellular bacteria, intracellular bacteria, and fungi. Emerging trends suggest
that the Th17 population bridges innate and adaptive immunity to produce a robust antimicrobial inflammatory response. However,
because Th17 cells mediate both host defense and pathological inflammation, elucidation of mechanisms that attenuate but do
not completely abolish the Th17 response may have powerful implications for therapy.

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Available from: Elizabeth Mellins, Dec 17, 2013
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