ABSTRACT
Exosomes are membranous vesicles secreted by cells and can be widely involved in intercellular communication, anti-inflammation, immunoregulation, etc.Mesenchymal stem cell (MSC), regulatory T cell (Treg), immature dendritic cell (imDC) and myeloid-derived suppressor cell (MDSC) are the main ocular surface-related exosomes origins.Exosomes derived from different cells play their roles by delivering different biological molecules to recipient cells.Exosomes derived from MSC play a positive role in ocular surface inflammation and immune-related diseases by inhibiting T cell proliferation, transforming macrophage phenotype, regulating T helper (Th) cell differentiation and up-regulating Treg expression, reduce neovascularization and inflammation, and foster a microenvironment to promote corneal wound healing at the same time.Exosomes derived from Treg contain inducible NO synthase and microRNA (miRNA) including miR-503, miR-330 and miR-9, which can interfere with cell cycle progression, induce apoptosis, induce the differentiation of other T cells into Treg phenotype, inhibit T cell allograft rejection to induce immune tolerance.Exosomes derived from imDC inhibit corneal allograft rejection by delivering miR-682.MDSC-derived exosomes promote Treg expansion in vivo and in vitro, inhibit the proliferation and cytotoxicity of activated T cells, and express miR-29a-3p and miR-93-5p, which can inhibit the differentiation of Th1 and Th17 cells.Given the anti-inflammatory and immunosuppressive effects of exosomes, this paper reviewed the studies on ocular surface inflammation and immune-related diseases such as corneal injury, mucopolysaccharide storage disease, dry eye, Sj?gren syndrome and ocular graft-versus-host disease.
ABSTRACT
Objective:To establish a fast method for the generation of immature dendritic cells(DCs) from human peripheral blood mononuclear cells(hPBMCs) in vitro.Methods: High purity human CD14+ monocytes were collected using density Ficoll gradient centrifugation and MACS beads sorting system.iDCs(Immature DC) were induced after cultured with rhGM-CSF and rhIL-4 on the fourth day.Fluorescence activated cell sorting(FACS) was used to identify cell surface markers(CCR5) and capabilities of antigen uptake of iDCs on the fourth day.Ordinary optical microscope,scanning electron microscopy and transmission electron microscopy were used to observe surface and internal structure of iDCs on the fourth day of culture conditions.Results: FACS result shows that the purity of CD14+ monocytes collected from hPBMCs were more than 94%.The antigen uptake capability and CD195 of iDCs was detected on the fourth day of cultured conditions.Typical surface and internal structure characteristics of iDCs were observed.Conclusion: Rapid induction culture is an effective method for obtaining a large number of iDC with typical characteristics in vitro,and can be used for further experimental study.
ABSTRACT
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-?,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
ABSTRACT
Objective:To explore the possibly mechanisms of inducing allogeneic chimerism and prolonging allografts survival in recipients by immature dendritic cells (imDCs) Methods:Bone marrow cells (BMCs) derived from donor (C57BL/6) were used to generate imDCs The splenocytes of recipients were pretreated by inactivated imDCs in vitro, or the recipients (Balb/C) were injected of inactivated imDCs via vein in vivo Then collected the splenocytes mixed with the inactivated splenocytes from donor to detect the responsiveness Mixed lymphocyte reaction was also used to evaluate the reactivity of the chimerism mice to the donor splenocytes At the same time the diversion of Th1/Th2 paradigm was studied by semi quantitative RT PCR Results:The splenocytes conditioned with imDCs pretreatment expressed hypo responsiveness to the donor stimulation, and the immunized mice also proliferated less degree compared with the naive mice The hyporeactivity was evidently seen within 72 hours after stimulation by donor splenocytes There was significant difference between them The chimerism mice showed unresponsiveness to donor antigens, while reactivity to the third party antigens was retained The result of RT PCR suggested, to some extent, there was a diversion of Th1/Th2 paradigm in the establishment of chimerism in the model Conclusion:The putative mechanism of immature dendritic cells inducing the generation of allogeneic chimerism may based on the hypo responsiveness produced by imDCs, and there may also exist some kinds of diversion of Th1/Th2 paradigm
ABSTRACT
100 d) than those injected BMCs at the fifth day (
ABSTRACT
Objective To observe the morphologic changes of immature dendritic cells(imDCs) before and after the electransfection of human hepatic cancer cell RNA. Methods Monocytes were purified from human peripheral blood,and induced into imDCs.Then human hepatic cancer cell RNA was electransfected into monocyte-derived imDCs.ImDCs were identified by the immunocytochemical method with 7 specific antibodies before and after electransfection.These dendritic cells were observed by scanning electron microscopy. Results After electransfection of human hepatic cancer cell RNA there were few changes of molecule expressions in imDCs.ImDCs were in round,oval and irregular shapes before electransfection.Their sizes were not identical but all bigger than monocytes.There were many protrusions in different shapes which looked like dendrite,or/and bubble,veil cloud on the surface of these imDCs.Although there were some cell fusions and cell deaths after electransfection,most imDCs recovered from the damage.Electransfecting human hepatic cancer cell RNA into imDCs would make pores on cell membrane.Conclusions The pores on cell membrane make it possible that the exogenous material enters imDCs.This study can prove the possibility of electransfecting human hepatic cancer cell RNA into imDCs to make cancer vaccine,which provides a new way for tumor biologic therapy.