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Byline: Fukun Guo (1), Shuguang Wu (2) Abstract: Antisense interleukin-1 (IL-1) receptor associated kinase-2 (IRAK-2) oligonucleotide (ODN) and antisense p110 PI 3-kinase ODN blocked IRAK-2 and p110 PI 3-kinase expression, respectively. As a result, antisense IRAK-2 ODN or antisense p110 PI 3-kinase ODN inhibited IL-1-induced NF-IoB and AP-1 activation in HepG2 cells. The inhibition of NF-IoB activation by antisense IRAK-2 ODN or antisense p110 PI 3-kinase ODN and the inhibition of AP-1 activation by antisense IRAK-2 ODN were incomplete, whereas AP-1 activation could be inhibited by antisense p110 PI 3-kinase ODN completely. These results indicate that IRAK-2 is necessary but insufficient to activate NF-IoB and AP-1 completely and that although PI 3-kinase is not sufficient for NF-IoB full activation, it is sufficient to activate AP-1 completely. The effects of IRAK-2 or PI 3-kinase on NF-IoB and AP-1 activation were confirmed by the results that overexpression of IRAK-2 failed to fully activate NF-IoB and AP-1 and that overexpression of p110 PI 3-kinase is insufficient for NF-IoB full activation but sufficient for AP-1 activation. Cotransfection experiments showed that the combination of antisense IRAK-2 ODN and antisense p110 PI 3-kinase ODN resulted in additive inhibition of NF-IoB as well as AP-1 activation. On the other hand, coexpression of IRAK-2 with p110 PI 3-kinase led to a synergistic activation of NF-IoB and AP-1. These data suggest that IRAK-2 and PI 3-kinase cooperate to activate NF-IoB and AP-1. Author Affiliation: (1) Institute of Pharmaceutic Sciences, The First Military Medical University, Guangzhou, 510515, China (2) Institute of Pharmaceutic Sciences, The First Military Medical University, Guangzhou, 510515, China Article History: Registration Date: 09/10/2004

Byline: Fukun Guo (1), Yilei Li (1), Shuguang Wu (1) Abstract: Phosphorothioate oligodeoxynucleotide (ODN) was designed antisense to sequences of the recently cloned human IL-1 receptor associated kinase-2 (IRAK-2). Antisense IRAK-2 ODN was delivered by lipofectin encapsulation into cultured endothelial cells. The levels of NF-IoB, surface expression of intracellular adhesion molecule-1 (ICAM-1), ICAM-1 and IRAK-2 mRNAs were measured by sandwich ELISA, ELISA on cells in situ, and semiquantitative reverse transcription-PCR (RT-PCR), respectively. Antisense IRAK-2 ODN inhibited IL-1-induced NF-IoB activation and surface expression of ICAM-1 in a concentration (1--4 ug)- and time (5--24 h)-dependent fashion. A maximum inhibition of NF-IoB activation or surface expression of ICAM-l occurred when the cells were incubated with antisense IRAK-2 ODN 3 ug for 8 h. IL-1-induced ICAM-1 mRNA expression was also inhibited after treatment of cells with antisense IRAK-2 ODN 3 ug for 8 h. The attenuation of the cellular response to IL-1 caused by antisense IRAK-2 ODN correlated with a reduction of IRAK-2 expression. These data suggest that antisense IRAK-2 ODN may share a role in the design of antiinflammatory therapeutics. Author Affiliation: (1) Institute of Pharmaceutic Sciences, The First Military Medical University, Guang Zhou, 510515, China Article History: Registration Date: 30/09/2004