Micro RNA-155 participates in re-activation of encephalitogenic T cells.
MicroRNAs (miR) are small non-coding RNAs involved in the immune response regulation. miR-155 has been attributed a major pro-inflammatory role in the pathogenesis of multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE). Here, a role of miR-155 in re-activation of encephalitogenic CD4(+) T cells was investigated. Dark Agouti rats were immunized with myelin basic protein (MBP) emulsified in complete Freund's adjuvant. CD4(+) T cells were purified from draining lymph node cells (DLNC) obtained in the inductive phase and from spinal cord immune cells (SCIC) isolated at the peak of EAE. CD4(+) T cells obtained from SCIC (i.e., in vivo re-activated cells) had markedly higher expression of miR-155 in comparison to those purified from DLNC (not re-activated). Likewise, in vitro re-activation of DLNC with MBP led to increase in miR-155 expression. Further, DLNC and DLNC CD4(+) T cells were transfected with an inhibitor of miR-155 during in vitro re-activation. As a result, expression of important CD4(+) T cell effector cytokines IFN-γ and IL-17, but not of regulatory cytokines IL-10 and TGF-β, was reduced. These results imply that miR-155 supports re-activation of encephalitogenic CD4(+) T cells. Our results contribute to a view that miR-155 might be a valuable target in multiple sclerosis therapy.
Department of Immunology, Institute for Biological Research "SinišaStanković", University of Belgrade, Serbia.
Bojan
B
Jevtić
Institute of Molecular Genetics and Genetic Engineering, University of Belgrade, Serbia.
Gordana
G
Timotijević
Department of Immunology, Institute for Biological Research "SinišaStanković", University of Belgrade, Serbia.
Suzana
S
Stanisavljević
Department of Immunology, Institute for Biological Research "SinišaStanković", University of Belgrade, Serbia.
Miljana
M
Momčilović
Institute for Microbiology and Immunology, School of Medicine, University of Belgrade, Serbia.
Marija
M
Mostarica Stojković
Department of Immunology, Institute for Biological Research "SinišaStanković", University of Belgrade, Serbia.
Djordje
D
Miljković
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016207:Cytokines / Q000276:immunology*; D004195:Disease Models, Animal; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000235:genetics / Q000276:immunology / Q000503:physiopathology*; D005260:Female; D005786:Gene Expression Regulation; D035683:MicroRNAs / Q000235:genetics*; D009103:Multiple Sclerosis / Q000235:genetics / Q000503:physiopathology; D004676:Myelin Basic Protein / Q000276:immunology; D051381:Rats; D013116:Spinal Cord / Q000276:immunology
D016207:Cytokines; C580597:MIRN155 microRNA, rat; D035683:MicroRNAs; D004676:Myelin Basic Protein
Autoimmunity; Central nervous system; Cytokines; micro RNA