Article

Functional Specialization of Interleukin-17 Family Members

Laboratory of Molecular Pathogenesis, Center for Experimental Medicine and Systems Biology, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo, Japan.
Immunity (Impact Factor: 19.75). 02/2011; 34(2):149-62. DOI: 10.1016/j.immuni.2011.02.012
Source: PubMed

ABSTRACT Interleukin-17A (IL-17A) is the signature cytokine of the recently identified T helper 17 (Th17) cell subset. IL-17 has six family members (IL-17A to IL-17F). Although IL-17A and IL-17F share the highest amino acid sequence homology, they perform distinct functions; IL-17A is involved in the development of autoimmunity, inflammation, and tumors, and also plays important roles in the host defenses against bacterial and fungal infections, whereas IL-17F is mainly involved in mucosal host defense mechanisms. IL-17E (IL-25) is an amplifier of Th2 immune responses. The functions of IL-17B, IL-17C, and IL-17D remain largely elusive. In this review, we describe the identified functions of each IL-17 family member and discuss the potential of these molecules as therapeutic targets.

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