LncRNA GAS5 inhibits Th17 differentiation and alleviates immune thrombocytopenia via promoting the ubiquitination of STAT3

Int Immunopharmacol. 2020 Mar:80:106127. doi: 10.1016/j.intimp.2019.106127. Epub 2020 Jan 21.

Abstract

Background: The increased differentiation of T helper 17 cells (Th17) accelerates the development of immune thrombocytopenia (ITP), which is a common autoimmune disease with limited therapeutic methods. Recent studies have revealed that long non-coding RNAs (lncRNAs) play a critical role in autoimmune diseases, thus this study aims to investigate the effect of lncRNA GAS5 on the differentiation of Th17 cells in ITP.

Methods: The expression of GAS5 in peripheral blood mononuclear cells (PBMCs) of ITP patients and spleen tissues of ITP mice was measured by qRT-PCR. The percentage of Th17 cells in CD4+ cells was measured by flow cytometry. The combination between GAS5 and STAT3 was confirmed by RNA pull-down assay and RNA Binding Protein Immunoprecipitation (RIP). The ubiquitination of STAT3 was detected by ubiquitination assay and the interaction between STAT3 and TRAF6 was measured by Co-Immunoprecipitation (Co-IP). Finally, the effect of GAS5 on Th17 differentiation was investigated in vitro and in vivo using lentivirus (lenti)-GAS5.

Results: GAS5 expression was downregulated both in PBMCs of ITP patients and spleen tissues of ITP mice. Overexpression of GAS5 suppressed Th17 differentiation while had no effect on Treg differentiation in naïve CD4+ cells. RNA pull-down and RNA immunoprecipitation assays confirmed the interaction between GAS5 and STAT3. Further studies showed GAS5 accelerated the degradation of STAT3 via promoting TRAF6-mediated ubiquitination. Overexpressing GAS5 suppressed Th17 differentiation in vitro and alleviated ITP in vivo via reducing STAT3.

Conclusion: LncRNA GAS5 inhibited Th17 differentiation through promoting the TRAF6-mediated ubiquitination of STAT3, thus relieving ITP.

Keywords: Immune thrombocytopenia; LncRNA GAS5; STAT3; Th17 differentiation; Ubiquitination.

MeSH terms

  • Adult
  • Animals
  • Case-Control Studies
  • Cell Differentiation / genetics
  • Cell Differentiation / immunology
  • Disease Models, Animal
  • Down-Regulation / immunology
  • Female
  • Humans
  • Intracellular Signaling Peptides and Proteins / genetics
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Male
  • Mice
  • Middle Aged
  • Proteolysis
  • RNA, Long Noncoding / metabolism*
  • STAT3 Transcription Factor / metabolism*
  • Spleen / immunology
  • Spleen / pathology
  • TNF Receptor-Associated Factor 6 / genetics
  • TNF Receptor-Associated Factor 6 / metabolism
  • Th17 Cells / immunology*
  • Thrombocytopenia / blood
  • Thrombocytopenia / genetics*
  • Thrombocytopenia / immunology
  • Thrombocytopenia / pathology
  • Ubiquitination / genetics

Substances

  • GAS5 long non-coding RNA, human
  • Intracellular Signaling Peptides and Proteins
  • RNA, Long Noncoding
  • STAT3 Transcription Factor
  • STAT3 protein, human
  • Stat3 protein, mouse
  • TNF Receptor-Associated Factor 6
  • TRAF6 protein, mouse
  • Tifab protein, human
  • long non-coding RNA GAS5, mouse