Transcriptional Interactomic Inhibition of RORα Suppresses Th17-Related Inflammation

Chun-Chang Ho; Giha Kim; Chin Hee Mun; Ju-Won Kim; Jieun Han; Ji Yoon Park; Yong-Beom Park; Sang-Kyou Lee

doi:10.2147/JIR.S344031

Transcriptional Interactomic Inhibition of RORα Suppresses Th17-Related Inflammation

J Inflamm Res. 2021 Dec 21:14:7091-7105. doi: 10.2147/JIR.S344031. eCollection 2021.

Authors

Chun-Chang Ho¹, Giha Kim¹, Chin Hee Mun², Ju-Won Kim³, Jieun Han³, Ji Yoon Park¹, Yong-Beom Park^{2

3

4}, Sang-Kyou Lee^{1

5}

Affiliations

¹ Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, Republic of Korea.
² Division of Rheumatology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea.
³ Department of Medical Science, Brain Korea 21 PLUS Project, Yonsei University, Seoul, Republic of Korea.
⁴ Institute for Immunology and Immunological Diseases, Yonsei University College of Medicine, Seoul, Republic of Korea.
⁵ Good T Cells, Inc., Seoul, Republic of Korea.

Abstract

Purpose: Th17 cells and their cytokines are implicated in the pathogenesis of various autoimmune diseases. Retinoic acid-related orphan receptor alpha (RORα) is a transcription factor for the differentiation and the inflammatory functions of Th17 cells. In this study, we generated the nucleus-transducible form of transcription modulation domain of RORα (nt-RORα-TMD) to investigate the functional roles of RORα in vitro and in vivo under normal physiological condition without genetic alteration.

Methods: The functions of nt-RORα-TMD were analyzed in vitro through flow cytometry, luciferase assay, ELISA, and transcriptome sequencing. Finally, the in vivo therapeutic effects of nt-RORα-TMD were verified in dextran sulfate sodium (DSS)-induced colitis mice.

Results: nt-RORα-TMD was effectively delivered into the cell nucleus in a dose- and time-dependent manner without any cellular toxicity. nt-RORα-TMD competitively inhibited the RORα-mediated transcription but not RORγt-mediated transcription. Secretion of IL-17A from the splenocytes was suppressed by nt-RORα-TMD without affecting the secretion of Th1- or Th2-type cytokine and T cell activation events such as induction of CD69 and CD25. The differentiation potential of naïve T cells into Th17 cells, not into Th1, Th2, or Treg cells, was significantly blocked by nt-RORα-TMD. Consistently, mRNA sequencing analysis showed that nt-RORα-TMD treatment down-regulated the expression of the genes related to the differentiation and functions of Th17 cells. Treatment of DSS-induced colitis mice with nt-RORα-TMD improved the overall symptoms of colitis, such as body weight change, colon length, infiltration of inflammatory cells, and the level of inflammatory cytokines in the serum. In the mesenteric lymph node (MLN) of the nt-RORα-TMD-treated mice, the population of CD4+IL-17A+ Th17 cells was reduced, and the population of CD4+Foxp3+ Treg cells increased.

Conclusion: nt-RORα-TMD has a potential to be developed as a novel therapeutic reagent for treating various inflammatory diseases in which Th17 cells are the leading pathological player.

Keywords: DSS-induced colitis; T helper 17; inflammatory disease; retinoic acid-related orphan receptor; transcriptional modulation.

Grants and funding

This work was supported by a Global Research Laboratory (GRL) Program of the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIP) (NRF-2016K1A1A2912755) and a Basic Science Research Program of the NRF grant funded by the Ministry of Education (2019R1I1A1A01064332), and the Brain Korea 21 (BK21) PLUS Program, Republic of Korea.