title: Nuclear presence of nuclear factor of activated T cells (NFAT) c3 and c4 is required for Toll-like receptor-activated innate inflammatory response of monocytes/macrophages.
abstract: Nuclear factor of activated T cells (NFATs) are crucial transcription factors that tightly control proinflammatory cytokine expression for adaptive immunity in T and B lymphocytes. However, little is known about the role of NFATs for innate immunity in macrophages. In this study, we report that NFAT is required for Toll-like receptor (TLR)-initiated innate immune responses in bone marrow-derived macrophages (BMMs). All TLR ligand stimulation including LPS, a TLR4 ligand, and Pam(3)CSK(4), a TLR1/2 ligand, induced expression of TNF which was inhibited by VIVIT, an NFAT-specific inhibitor peptide. BMMs from NFATc4 knock-out mouse expressed less TNF than wild type. Despite apparent association between NFAT and TNF, LPS did not directly activate NFAT based on NFAT-luciferase reporter assay, whereas NF-κB was inducibly activated by LPS. Instead, macrophage exhibited constitutive NFAT activity which was not increased by LPS and was decreased by VIVIT. Immunocytochemical examination of NFATc1-4 of BMMs exhibited nuclear localization of NFATc3/c4 regardless of LPS stimulation. LPS stimulation did not cause nuclear translocation of NFATc1/c2. Treatment with VIVIT resulted in nuclear export of NFATc3/c4 and inhibited TLR-activated TNF expression, suggesting that nuclear residence of NFATc is required for TLR-related innate immune response. Chromatin immunoprecipitation (ChIP) assay using anti-RNA polymerase II (PolII) antibody suggested that VIVIT decreased PolII binding to TNF gene locus, consistent with VIVIT inhibition of LPS-induced TNF mRNA expression. This study identifies a novel paradigm of innate immune regulation rendered by NFAT which is a well known family of adaptive immune regulatory proteins.
authors: Center for Orthopaedic Research, Department of Orthopaedic Surgery, Columbia University, 650 West 168th Street BB14-1412, New York, NY 10032, USA.
authors: Hiroshi
authors: H
authors: Minematsu
authors: Mike J
authors: MJ
authors: Shin
authors: Ayse B
authors: AB
authors: Celil Aydemir
authors: Kyung-Ok
authors: KO
authors: Kim
authors: Saqib A
authors: SA
authors: Nizami
authors: Gook-Jin
authors: GJ
authors: Chung
authors: Francis Young-In
authors: FY
authors: Lee
mesh_terms: D000818:Animals; D001853:Bone Marrow / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D002467:Cell Nucleus / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D047369:Chromatin Immunoprecipitation; D016207:Cytokines / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007113:Immunity, Innate; D007150:Immunohistochemistry; D055666:Lipopeptides / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D009000:Monocytes / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D016328:NF-kappa B / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D050778:NFATC Transcription Factors / Q000172:deficiency* / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D061251:Primary Cell Culture; D012319:RNA Polymerase II / Q000037:antagonists & inhibitors / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis; D015398:Signal Transduction / Q000187:drug effects / Q000276:immunology*; D051193:Toll-Like Receptors / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology / Q000378:metabolism
chemical_list: D016207:Cytokines; D055666:Lipopeptides; D008070:Lipopolysaccharides; D016328:NF-kappa B; D050778:NFATC Transcription Factors; D009842:Oligopeptides; C508075:Pam(3)CSK(4) peptide; D012333:RNA, Messenger; D051193:Toll-Like Receptors; D014409:Tumor Necrosis Factor-alpha; C121611:VIVIT peptide; C445503:transcription factor NF-AT c3; D012319:RNA Polymerase II