title: DCs sensitized with mPD-L1-Ig fusion protein improve the effect of heart transplantation in mice by promoting the generation of T-reg cells.
abstract: OBJECTIVE
  To detect the effects of DCs sensitized by mPD-L1-Ig fusion protein in heart transplantation in mice as well as its mechanisms.
  
  
  METHODS
  The mPD-L1-IgG1 construct was used to build a yeast expression system, and the fusion protein was expressed by secretion after the transfection of the GS115 yeast strain, purified by affinity chromatography and ion exchange chromatography, and assayed by SDS-PAGE and Western blot. The ability of the fusion protein to bind to the acceptor PD-1 was tested by ELISA, and the ability of the fusion protein to inhibit the function of T cells was tested by mixed lymphocyte reaction (MLR).
  
  
  RESULTS
  We used the new PD-L1-IgG1 fusion protein to sensitize imDCs and maintained the immature state of DCs, so as to induce stable and effective immune tolerance to heart transplantation. After the treatment of DCs by mPD-L1-Ig in vitro, the levels of CD80, CD40 and I-Ab expression on DCs are relatively weaker, the ability of DCs to stimulates the proliferation of allogeneic spleen T cells was significantly decreased (P<0.01), and the levels of Th1 (IL-2, IFN-γ) and Th2 (IL-4, IL-10) secreted by induced allogeneic T cells were significantly decreased (P<0.01). An in vivo experiment also revealed that DCs sensitized by mPD-L1-IgG1 could prolong the survival time of a transplanted heart to 17.8±1.12days, and alleviate the pathological change of the cardiac allografts compared with other three groups.
  
  
  CONCLUSIONS
  DCs sensitized by the yeast-expressed mPD-L1-Ig fusion protein are shown to alleviate the cardiac allograft rejection in mice.
authors.affiliation: Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai 20032, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai 20032, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.affiliation: Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai 20032, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Jia
authors.affiliation: Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai 20032, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Hong
authors.affiliation: Department of Cardiac Surgery, Zhongshan Hospital, Fudan University, Shanghai 20032, China. Electronic address: chunshengwang021@hotmail.com.
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Wang
mesh_terms: D000818:Animals; D018122:B7-1 Antigen / Q000096:biosynthesis; D060890:B7-H1 Antigen / Q000276:immunology* / Q000378:metabolism; D019013:CD40 Antigens / Q000096:biosynthesis; D049109:Cell Proliferation; D003713:Dendritic Cells / Q000276:immunology*; D005260:Female; D006084:Graft Rejection / Q000276:immunology / Q000517:prevention & control*; D016027:Heart Transplantation; D007371:Interferon-gamma / Q000097:blood / Q000378:metabolism; D016753:Interleukin-10 / Q000097:blood / Q000378:metabolism; D007376:Interleukin-2 / Q000097:blood / Q000378:metabolism; D015847:Interleukin-4 / Q000097:blood / Q000378:metabolism; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D061026:Programmed Cell Death 1 Receptor / Q000276:immunology / Q000378:metabolism; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000276:immunology; D013154:Spleen / Q000166:cytology; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D023001:Transplantation Tolerance / Q000276:immunology*
chemical_list: D018122:B7-1 Antigen; D060890:B7-H1 Antigen; D019013:CD40 Antigens; C498919:Cd274 protein, mouse; C556062:IL10 protein, mouse; D007376:Interleukin-2; C491383:Pdcd1 protein, mouse; D061026:Programmed Cell Death 1 Receptor; D011993:Recombinant Fusion Proteins; D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma
keywords: DCs; Fusion protein; Immune tolerance; PD-L1; T-reg cells