Open AccessInhibition of Human Immunodeficiency Virus Type 1 Replication in Latently Infected Cells by a Novel IκB Kinase Inhibitor
Author(s) -
Ann Florence B. Victoriano,
Kaori Asamitsu,
Yurina Hibi,
Kenichi Imai,
Nina G. Barzaga,
Takashi Okamoto
Publication year - 2006
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.50.2.547-555.2006
Subject(s) - iκb kinase , biology , hiv long terminal repeat , viral replication , kinase , tumor necrosis factor alpha , iκbα , phosphorylation , microbiology and biotechnology , virology , cell culture , western blot , chromatin immunoprecipitation , jurkat cells , downregulation and upregulation , signal transduction , nf κb , virus , long terminal repeat , gene expression , immunology , t cell , biochemistry , gene , immune system , promoter , genetics
In human immunodeficiency virus type 1 (HIV-1) latently infected cells, NF-κB plays a major role in the transcriptional induction of HIV-1 replication. Hence, downregulation of NF-κB activation has long been sought for effective anti-HIV therapy. Tumor necrosis factor alpha (TNF-α) stimulates IκB kinase (IKK) complex, a critical regulator in the NF-κB signaling pathway. A novel IKK inhibitor, ACHP {2-amino-6-[2-(cyclopropylmethoxy)-6-hydroxyphenyl]-4-piperidin-4-yl-nicotinonitrile}, was developed and evaluated as a potent and specific inhibitor for IKK-α and IKK-β. In this study, we examined the ability of this compound to inhibit HIV-1 replication in OM10.1 cells latently infected with HIV. When these cells were pretreated with ACHP, TNF-α-induced HIV-1 replication was dramatically inhibited, as measured by the HIV p24 antigen levels in the culture supernatants. Its 50% effective concentration was approximately 0.56 μM, whereas its 50% cytotoxic concentration was about 15 μM. Western blot analysis revealed inhibition of IκBα phosphorylation, IκBα degradation, p65 nuclear translocation, and p65 phosphorylation. ACHP was also found to suppress HIV-1 long terminal repeat (LTR)-driven gene expression through the inhibition of NF-κB activation. Furthermore, ACHP inhibited TNF-α-induced NF-κB (p65) recruitment to the HIV-1 LTR, as assessed by chromatin immunoprecipitation assay. These findings suggest that ACHP acts as a potent suppressor of TNF-α-induced HIV replication in latently infected cells and that this inhibition is mediated through suppression of IKK activity.