Application study on adoptive transfusion of tolerogenic dendritic cells in promoting immune tolerance of liver transplantation in rat models / 器官移植

ABSTRACT

Objective To investigate the role of tolerogenic dendritic cell (tolDC) in inducing immune tolerance in liver transplantation. Methods Liver transplantation rat models of spontaneous tolerance [Brown Norway (BN)→Lewis, tolerance group, n=6] and acute rejection (AR) (Lewis→BN) were established. In AR rat models, tolDC transfusion was performed in the study group (tolDC group, n=6) and no intervention was given in the control group (AR group, n=6). The survival time of rats in each group was observed. The transplant liver tissues of rats were prepared for pathological examination in each group. The expression of myeloid dendritic cell (mDC) and plasmacytoid dendritic cell (pDC) in rat peripheral blood, transplant liver, spleen and lymph nodes in each group was detected by flow cytometry. The expression levels of serum interleukin (IL)-10 and interferon (IFN)-γ in each group were measured by enzyme-linked immune absorbent assay. Results Pathological manifestations of rats in the AR group mainly included inflammatory cell infiltration and tissue structural disorder in transplant liver, and the survival time was 7-14 d. In the tolDC and tolerance groups, the transplant liver tissues were almost normal, and the longest survival time exceeded 100 d. Compared with the AR group, the expression levels of CD11+mDC in peripheral blood, transplant liver, spleen and lymph nodes of rats were significantly down-regulated in the tolerance and tolDC groups (all P < 0.05), and those of CD86 and major histocompatibility complex (MHC)Ⅱon the surface of CD11+mDC were also significantly down-regulated (all P < 0.05). Compared with the AR group, the expression levels of pDC in peripheral blood, transplant liver, spleen and lymph nodes of rats were significantly up-regulated in the tolerance and tolDC groups (all P < 0.05), whereas those of MHCⅡon the surface of pDC were all significantly down-regulated (all P < 0.05). Compared with the AR group, the expression levels of serum IL-10 were significantly up-regulated, and IFN-γ were significantly down-regulated in the tolerance and tolDC groups (all P < 0.05). Conclusions As tolDC subsets, mDC and pDC play a positive role in regulating the incidence of graft immune tolerance in rats after liver transplantation.