These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Lipoteichoic acid of Staphylococcus aureus enhances IL-6 expression in activated human basophils.
    Author: Jeon JH, Kim SK, Baik JE, Kang SS, Yun CH, Chung DK, Han SH.
    Journal: Comp Immunol Microbiol Infect Dis; 2012 Jul; 35(4):363-74. PubMed ID: 22445541.
    Abstract:
    At allergic inflammation, cross-linking of FcɛRI with multivalent antigen-bound IgE triggers the signaling pathways via activation of protein kinase C (PKC) and mobilization of intracellular Ca(2+) leading to the production of various mediators such as interleukin-6 (IL-6). Accumulating reports demonstrated that interaction of Toll-like receptor 2 (TLR2) expressed on basophils with a TLR2 ligand, lipoteichoic acid (LTA) of Staphylococcus aureus, exacerbated allergic inflammation. Here, we showed that staphylococcal LTA (Sa.LTA) substantially enhanced IL-6 expression at both the protein and the mRNA levels in the human basophil line, KU812, in the presence of a PKC activator (phorbol 12-myristrate 13-acetate; PMA), and a calcium ionophore (A23187), whereas Sa.LTA alone could not induce IL-6 expression. PMA/A23187 augmented the expression of CD14 and TLR2 on the surface of KU812 cells and concomitantly increased the binding of fluorochrome-labeled Sa.LTA to the cells. Sa.LTA enhanced the phosphorylation of mitogen-activated protein (MAP) kinases in PMA/A23187-stimulated KU812 cells. Notably, Sa.LTA could not enhance PMA/A23187-induced IL-6 expression in the presence of inhibitors of MAP kinases, reactive oxygen species, or protein kinase C. Furthermore, Sa.LTA enhanced the PMA/A23187-increased DNA-binding activities of the transcription factors NF-κB and AP-1. Experiments using human peripheral blood mononuclear cells demonstrated that not only PMA/A23187 but also Sa.LTA increased the intracellular IL-6 expression in the basophil population and Sa.LTA plus PMA/A23187 further enhanced the IL-6 expression. Collectively, these results suggest that Sa.LTA exacerbates allergic inflammation by potentiating IL-6 production from activated basophils.
    [Abstract] [Full Text] [Related] [New Search]