title: Adiponectin is a negative regulator of NK cell cytotoxicity.
abstract: NK cells are a key component of innate immune systems, and their activity is regulated by cytokines and hormones. Adiponectin, which is secreted from white adipose tissues, plays important roles in various diseases, including hypertension, cardiovascular diseases, inflammatory disorders, and cancer. In this study the effect of adiponectin on NK cell activity was investigated. Adiponectin was found to suppress the IL-2-enhanced cytotoxic activity of NK cells without affecting basal NK cell cytotoxicity and to inhibit IL-2-induced NF-kappaB activation via activation of the AMP-activated protein kinase, indicating that it suppresses IL-2-enhanced NK cell cytotoxicity through the AMP-activated protein kinase-mediated inhibition of NF-kappaB activation. IFN-gamma enhances NK cell cytotoxicity by causing an increase in the levels of expression of TRAIL and Fas ligand. The production of IFN-gamma, one of the NF-kappaB target genes in NK cells, was also found to be suppressed by adiponectin, accompanied by the subsequent down-regulation of IFN-gamma-inducible TRAIL and Fas ligand expression. These results clearly demonstrate that adiponectin is a potent negative regulator of IL-2-induced NK cell activation and thus may act as an in vivo regulator of anti-inflammatory functions.
authors: Laboratory of Molecular and Cellular Biology, Department of Life Science, Sookmyung Women's University, Seoul 140-742, Korea.
authors: Kun-Yong
authors: KY
authors: Kim
authors: Jae Kwang
authors: JK
authors: Kim
authors: Seung Hyun
authors: SH
authors: Han
authors: Jong-Seok
authors: JS
authors: Lim
authors: Keun Il
authors: KI
authors: Kim
authors: Dae Ho
authors: DH
authors: Cho
authors: Myeong-Sok
authors: MS
authors: Lee
authors: Jeong-Hyung
authors: JH
authors: Lee
authors: Do-Young
authors: DY
authors: Yoon
authors: Suk Ran
authors: SR
authors: Yoon
authors: Jin Woong
authors: JW
authors: Chung
authors: Inpyo
authors: I
authors: Choi
authors: Eunjoon
authors: E
authors: Kim
authors: Young
authors: Y
authors: Yang