Study on the Effect of PD-L1 on Inflammatory Bowel Disease
염증성 장질환에서의 PD-L1의 효과에 관한 연구
- 주제(키워드) PD-L1 , DSS colitis , T cell colitis , IBD
- 발행기관 포항공과대학교 일반대학원
- 지도교수 성영철
- 발행년도 2014
- 학위수여년월 2014. 8
- 학위명 박사
- 학과 및 전공 일반대학원 융합생명공학부
- 세부전공 세포 면역학
- 원문페이지 64
- 실제URI http://www.dcollection.net/handler/postech/000001736688
- 본문언어 영어
- 저작권 포항공과대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Programmed death-ligand 1 (PD-L1) has been shown to negatively regulate immune responses via its interaction with PD-1 receptor. In this study, the effects of PD-L1 on intestinal inflammation was investigated using two murine models of inflammatory colitis induced by dextran sulfate sodium (DSS) and CD4+ CD45RBhigh T cell transfer. The anti-colitis effect of adenovirus expressing nonlytic Fc-conjugated PD-L1 (Ad/PD-L1-Fc) and recombinant PD-L1-Fc protein was evaluated in DSS-treated wild-type and Rag-1 knockout (KO) mice. It was examined about differentiation of T helper cells, frequency of innate immune cells, and cytokine production by dendritic cells (DCs) in the colon from DSS-treated mice after PD-L1-Fc administration. In Rag-1 KO mice reconstituted with CD4+ CD45RBhigh T cells, treatment effect of PD-L1-Fc protein was assessed during development of colitis. This study demonstrated for the first time that administration of PD-L1-Fc, either in the form of recombinant protein or by utilizing adenoviral vector as a delivery vehicle, could ameliorate DSS-induced colitis. The therapeutic effect of PD-L1-Fc in DSS colitic mice was associated with decreased frequency of interleukin (IL)-17A-producing CD4+ T cells and increased IFN--producing CD4+ T cells in the colon. The anti-colitic effect of PD-L1-Fc treatment was also observed in DSS-treated Rag-1 KO mice, indicating lymphoid cell independency. PD-L1-Fc modulated cytokine secretion by colonic DCs and the effects was dependent on PD-1 expression upon toll-like receptor (TLR) stimulation. Furthermore, PD-L1-Fc protein could significantly reduce the severity of colitis in CD4+ CD45RBhigh T cell-transferred Rag-1 KO mice. Based on the protective effect of PD-L1-Fc against DSS-induced acute and T cell-induced chronic colitis, these results suggest that PD-1-mediated inhibitory signals have a crucial role in limiting the development of colonic inflammation. This implicates that PD-L1-Fc may provide a novel therapeutic approach to treat inflammatory bowel disease.
more목차
Abstract ---------------------------------------------- I
Contents -------------------------------------------- III
List of Tables and Figures ---------------------------- V
Abbreviations --------------------------------------- VII
Chapter 1. Background
1-1. Inflammatory Bowel Disease ----------------------- 1
1-2. Biological Therapy for Inflammatory Bowel Disease 2
1-3. Programmed Death-1 and Its Ligands --------------- 3
1-4. Materials and Methods ---------------------------- 4
Chapter 2. Protective Effects of Fc-Fused PD-L1 on Two Different Animal Models of Colitis
2-1. Treatment with PD-L1-Fc Ameliorates Acute DSS-Induced Experimental Colitis in Mice ----------------- 21
2-2. PD-L1-Fc Affects the Differentiation of Colonic T-Helper Cells in DSS-Induced Colitis ------------------ 22
2-3. PD-L1-Fc Diminishes the Frequency of Innate Immune Cells in the Colon of DSS-Treated Rag-1 KO Mice ------ 23
2-4. PD-L1-Fc Modulates the Production of Cytokines by Colonic DCs Expressing PD-1 -------------------------- 24
2-5. Administration of Recombinant PD-L1-Fc Protein Attenuates the Severity of T Cell-Induced Colitis ---- 26
2-6. Discussion -------------------------------------- 26
Summary in Korean ------------------------------------ 48
References ------------------------------------------- 50
Acknowledgements ------------------------------------- 56
Curriculum Vitae ------------------------------------- 59