Objective Tolerogenic DCs (Tol-DCs), a group of cells with imDC phenotype, can stably induce T cells low-reactivity and immune tolerance. We systematically reviewed the adoptive transfusion of Tol-DCs induced by different ways to prolong cardiac allograft survival and its possible mechanism. Method MEDLINE (1966 to March 2011), EMbase (1980 to March 2011), and ISI (inception to March 2011) were searched for identification of relevant studies. We used allogeneic heart graft survival time as endpoint outcome to analyze the effect of adoptive transfusion of Tol-DC on cardiac allograft. By integrating studies’ information, we summarized the mechanisms of Tol-DC in prolonging cardiac grafts. Results Four methods were used to induce Tol-DC in all of the 44 included studies including gene-modified, drug-intervened, cytokine-induced, and other-derived (liver-derived amp; spleen-derived) DCs. The results showed that all types of Tol-DC can effectively prolong graft survival, and the average extension of graft survival time for each group was as follows: 22.02 ± 21.9 days (3.2 folds to control group) in the gene modified group, 25.94 ± 16.9 days (4.3 folds) in the drug-intervened groups, 9.00 ± 8.13 days (1.9 folds) in the cytokine-induced group, and 10.69 ± 9.94 days (2.1 folds) in the other-derived group. The main mechanisms of Tol-DCs to prolong graft survival were as follows: a) induceT-cell hyporeactivity (detected by MLR); b) reduce the effect of cytotoxic lymphocyte (CTL); c) promote Th2 differentiation; d) induce Treg; e) induce chimerism. Conclusion For fully MHC mismatched allogeneic heart transplant recipients of inbred mouse, adoptive transfusion of Tol-DC, which can be gene-modified, drug-intervened, cytokine-induced, spleen-derived or liver-derived, can clearly prolong the survival of cardiac allograft or induce immune tolerance. Gene-modified and drug-induced Tol-DC can prolong graft survival most obviously. Having better reliability and stability than drug-induction, gene-modification is the best way to induce Tol-DCs at present. One-time intravenous infusion of 2 × 106 Tol-DC is a simple and feasible way to induce long-term graft survival. Multiple infusions will prolong it but increase the risk and cost. Adoptive transfusion of Tol-DC in conjunction with immunosuppressive agents may also prolong the graft survival time.
Objective To detect the anti-colon cancer ability of whole cell lysates pulsed dendritic cell (DC) which acts as an adjuvant. Methods Whole cell lysates of LoVo cells were extracted with freeze thawing method, then the monocyte-derived DC were pulsed with this cellular antigen. Subsequently, the capability of antigen pulsed DC to promote T lymphocytes proliferation and the ability of T lymphocytes to kill LoVo cells were detected by 3H-TdR incorporation and lactate dehydrogenase release methods, respectively. Results The whole cell lysates of LoVo cells pulsed DC significantly stimulated T cells proliferation, and the cytotoxicity abilities of primed T cells to kill LoVo cells were also enhanced. Conclusion Tumor cell lysates which act as the cellular antigen to pulse DC can improve the efficacy of anti-cancer immune response， which provides us an experimental evidence for cancer immunotherapy.
Objective To study the mechanism of immune hyporesponsiveness of allograft rejection induced by transfusion nonpufsed allopeptide syngeneic immature dendritic cell (imDC) generated from recipient bone marrow progenitors and to explore a possible strategy for liver allograft protection in clinic. Methods Forty experimental rats were randomly divided into 4 group: control group, cyclosporine A (CsA) group, mature DC (mDC) group and imDC group. In control group, Wistar rats only received liver transplantation. In CsA group, Wistar rats underwent liver transplantation plus CsA treatment 〔10 mg/（kg·d)〕. In mDC group, recipient-derived mDC 1×106 were infused intravenously through the penile vein to Wistar rats. In imDC group, ImDC with the dose of 1×106 were injected into Wistar rats via the dorsum vein of penile. In each group, five recipients were killed on the 10th day after transplantation, the other five recipients were left to observe survival time. The levels of ALT, AST, TBIL, IL-2, IFN-γ, IL-4 and IL-10 were detected. The acute rejection and the expression of FasL/Fas in the grafts were detected by HE and immunohistochemical staining. Western blot was used to detect Scurfin protein expression of CD4+ CD25+ T cells. Results The median survival time of the liver allografts in CsA group and imDC group were significantly longer than that in control group and mDC group ( P ＜ 0.05). The levels of ALT and TBIL in control group and mDC group were significantly higher than those in CsA group and imDC group ( P ＜ 0.05). Compared with CsA group and imDC group, the levels of IL-2 and IFN-γ were higher but the levels of IL-4 and IL-10 were lower in control group and mDC group ( P ＜ 0.01). Slightly or no rejection reaction was found in CsA group and imDC group ( P ＜ 0.05). The Scurfin protein expressions of CD4+ CD25+ T cells of imDC group were significantly higher than those of other three groups. Conclusion Application of nonpufsed allopeptide syngeneic recipient-derived imDC is an effective way to induce immune hyporesponsiveness by blocking indirect recognition in rat liver transplantation model. Survival span is significantly prolonged by its protective effect. The mechanism of immune hyporesponsiveness induced by imDC transfusion might be involved in some aspects: T cell apoptosis, immune deviation of Thl/Th2 cytokine net and inhibition of T lymphocytes responsiveness by regulatory T cells.
Objective To study the method of obtaining a large number of dendritic cells （DC）. To study the specific cytotoxicity T lymphocyte (CTL) effect against tumor cells initiated by DC pulsed with peptide of cancer cell. Methods Development of cells with cytologic features of DC in bone marrow cultures supplemented with granulocyte macrophage-colony stimulus factor (GM-CSF) and IL-4. Determining the DC phenotype and the specific structure by electronic microscopy. The CTL effect against pancreatic carcinoma leading by the DC pulsed with tumor cells lysate in vitro was observed. Results A large number of typical DC was proliferated by supplementing with GM-CSF and IL-4 cytokines. DC had specific cell appearance and structure, and highly expressed various cell surface molecules. TNF-α had the ability of stimulating DC mature, the mature DC had the enhancing abilities of antigen presenting and IL-12 self-secreting, as well as, expressed higher levels of CD54， MHC-Ⅱ and CD86 molecules than control group (P＜0.05). T lymphoid cell stimulated by DC without tumor antigen could not recognize and kill the target cells, only if DC pulsed with peptide of cancer cell can lead a b immune response to special tumor cells. The inhibiting ratio of CTL was significantly higher than that in other groups (P＜0.01). Conclusion Bone marrow DC has b ability of inducing special CTL against determined cancer cells after they are pulsed with tumor cell lysate. DC vaccine is probably a new immunotherapeutic method against tumor in the near future.
ObjectiveTo find out an effective method for amplification and purification of dendritic cells(DC) from peripheral blood of patients with pancreatic carcinoma. MethodsPeripheral blood mononuclear cells were purified from peripheral blood of health volunteers(control group,10 cases) and patients with pancreatic carcinoma (experimental group,12 cases) with incubation of granulocyte/macrophage colonystimulating factor(GMCSF) and interleukin4(IL4).The quality of DC were detected by immumofluorescence method and the expression levels of HLADR and B72 on DC were detected by flow cytometer after and before DC incubation with GMCSF and the IL4. ResultsThe expression level of HLADR and B72 of DC in experimental group were significantly less than those in control group(P＜0.01).DC in experimental group was significantly proliferated in the presence of GMCSF and IL4(P＜0.01).On day 7,the expression level of HLADR and B72 of DC in experimental group were significantly increased(P＜0.01) and there was no difference versus control group(Pgt;0.05).ConclusionIt is suggested that combination of GMCSF and IL4 can selectively and effectively enhance proliferation and immune function of DC from peripheral blood of patient with pancreatic carcinoma.
Objective To study the advances in the relationship between the number of infiltrating dendritic cells and the postoperative prognosis of digestive malignant tumor. MethodsThe literature in recent years on the relationship between the number of infiltrating dendritic cells and the postoperative prognosis of digestive malignant tumor was reviewed.ResultsThe number of infiltrating dendritic cells among esophageal cancer,and gastric carcinoma,colonic cancer and pancreatic cancer was associated with a better prognosis.Conclusion The population density of dendritic cells among the malignant tissue could be regarded as an independent indicator in estimating the postoperative prognosis of malignant tumor.
Objective To investigate the effects of FasL gene-modified dendritic cell (DC) on the airway inflammation in mice sensitized/challenged by house dust mite (HDM) allergen.Methods FasL gene-modified DC (FasL-DC) and control DC (nontransfection DC) were administrated into HDM sensitized and challenged mice by intratracheal injection respectively，then HDM sensitized and challenged mice were sacreificed two days later.Total and differentiation cell counts and levels of interleukin-4（IL-4），IL-5 and interferon-γ(IFN-) in bronchoalveolar lavage fluid (BALF) were detected and lung histological features were observed.Results After administration of FasL-DC，lung allergic inflammation was ameliorated while total cell counts，the percentage of eosinophil ,the levels of IL-4 and IL-5 in BALF decreased and the level of IFN- in BALF increased.Conclusion Administrating FasL-DC into HDM sensitized/challenged mice can inhibit Th2 cells activation and ameliorate airway allergic inflammation.
Objective To investigate the effects of nuclear factor kappa B decoy oligodeoxynucleotides ( NF-κB decoy ODN) transfection on biological characteristics of mature dendritic cells ( mDCs) in mice. Methods Immature DCs were harvested from Balb / c mice bone marrow, followed by the incubation with antigen OVA and LPS, and mature DCs were evaluated by the expressions of CD11c and MHC-Ⅱ detected by FACS. Mature DCs were transfected with NF-κB decoy ODN and the changes of NF-κB activity after the transfection were detected by EMSA. The expressions of the costimulatory molecules( CD40,CD80 and CD86) on DCs were detected by FACS and the proliferation of T cells was tested by mixed lymphocyte reaction( MLR) . Results The mature DCs were cultured successfully. The NF-κB activity of NF-κB decoy ODN transfected DCs was decreased significantly( P lt; 0. 05) . There was no difference in the expressions of CD40 and CD80, but the expression of CD86 was decreased significantly in NF-κB decoy ODN transfection group( P lt; 0. 05) . MLR test showed that the proliferation of T lymphocyte cells was inhibited by NF-κB decoy ODN transfected DCs, but was stimulated bly by the DCs of other groups. Conclusions Mature DCs transfected with NF-κB decoy ODN could inhibit the proliferation and activation of antigenspecical T cells, which was probably related to the down-regulation of CD86 on DCs. This modified DCs might be a promising vaccine for the treatment of asthma in the future.
Objective By using small interfering RNAs ( siRNAs) specific for spleen tyrosine kinase ( Syk) , to evaluate the role of Syk in maturation of bone marrow-derived dendritic cells. Methods The fragments of 21-23 bp siRNAs specific for mice Syk were chemo synthesized and transfected into the asthmatic murine bone marrow-derived dendritic cells ( BMDCs) by Lipofectamine 2000 transfection system for 48 hours. Then BMDCs were co-cultured with T cells from the normal mice spleen for 48 hours. The cytokines including IL-4, IL-13, IL-2 and INF-γin supernatant were detect by ELISA. The expression of Syk protein was measured by Western Blot to determine whether the Syk gene was silenced. Results The expression of Syk protein was obviously decreased in the siRNA-interference group. The secretions of IL-4 and IL-13 were significantly inhibited by siRNA interference ( P lt; 0. 05) , but the secretions of IL-2 and INF-γwere not interfered signficantly ( P gt;0. 05) . Conclusion Syk specific siRNA fragments can block the antigen presentation function of dendritic cells and block the activation and differentiation of T cells.