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1.
FTY720诱导大鼠心脏移植物长期存活   总被引:2,自引:0,他引:2  
目的 观察FTY720对大鼠同种异体心脏移植物存活时间的影响。方法 进行SD Wistar大鼠的腹部异位心脏移植,将受者随机分为对照组、甲泼尼龙(MP)组、环孢素A((SsA)组、FTY720组、FTY720与CsA二药联用组和FTY720、CsA及MP三药联用组,各组按分组要求分别于术前3d至术后14d通过灌胃给予FTY720和CsA,术前1d至术后2d腹腔注射给予MP,观察各组动物术后外周血淋巴细胞数量变化和移植物存活时间。结果 FTY720组、二药联用组和三药联用组的大鼠外周血淋巴细胞在给药后3h开始明显下降,停药后开始回升,至停药14d后恢复正常;移植心脏的存活时间,对照组平均为7.8d,CsA组为16.0d,MP组为27.6d,三药联用组为16.8d,而FTY720组和二药联用组分别超过了150d和124d。结论 FTY720可诱导同种异体大鼠心脏移植物长期存活。  相似文献   

2.
Interleukin‐33 (IL‐33) stimulates the generation of cells and cytokines characteristic of a Th2 immune response. We examined the effects of IL‐33 on allografted heart tissue in a chronic cardiac rejection model, including analysis of the peripheral myeloid and lymphoid compartments. B6.C‐H2bm12/KhEg hearts were transplanted into MHC class II‐mismatched C57Bl/6J mice; IL‐33 was administered daily. Cells from allografts and spleens were isolated for flow cytometry and cultured for cytokine production; some tissues were used for immunohistochemistry. Animals treated with IL‐33 showed significantly longer allograft survival, which was associated with a distinct cytokine profile produced by graft‐infiltrating cells. Proinflammatory IL‐17A production was decreased with IL‐33 treatment, while increased levels of IL‐5, IL‐10, and IL‐13 were observed. After IL‐33 therapy, flow cytometry showed a direct induction of CD4+ Foxp3+ Treg, whereas the number of B220+ CD19+ B cells, and circulating, as well as allograft deposited, alloantibodies was reduced. Following IL‐33 treatment, a significant decrease in graft‐infiltrating CD11bhighGr1high granulocytes coincided with a significant increase in CD11bhighGr1intermediate myeloid‐derived suppressor cells (MDSC). In conclusion, IL‐33 treatment in the setting of chronic rejection promotes the development of a Th2‐type immune response that favors MDSC and Treg expansion, reduces antibody‐mediated rejection (AMR), and ultimately, prolongs allograft survival.  相似文献   

3.
FTY720 is a recently discovered compound that is derived from the fungus Isaria sinclairii. Using a DA donor-to-LEW recipient rat combination, we assessed the efficacy of peritransplant FTY720 alone or in combination with post-transplant tacrolimus on the survival of cardiac allografts. Peritransplant FTY720 given orally at a dose of 5 mg/kg on days –1 and 0 prolonged graft survival from 5 to 13 days (P < 0.05). Combining peritransplant FTY720 with post-transplant tacrolimus resulted in a further prolongation of allograft survival. The lymphocyte count in transplanted rats decreased within 24 h to 46.6 %. Analysis of lymphocyte subsets by FACS revealed that FTY720 affected the total population of CD3-bearing T cells while the ratio of CD4 to CD8 cells remained unchanged. Kidney and liver biochemistry remained elevated for 2 weeks. In conclusion, FTY720 is a powerful immunosuppressive agent when used as induction therapy and may have an additive effect – perhaps a synergistic one – with post-transplant tacrolimus. Received: 27 October 1997 Received after revision: 23 March 1998 Accepted: 15 April 1998  相似文献   

4.
Sphingosine‐1‐phosphate (S1P) has recently been recognized as a crucial coupling molecule of osteoclast and osteoblast activity provoking osteoanabolic effects. Targeting S1P receptors could, therefore, be a potential strategy to support bone formation in osteopenic diseases or in fracture repair. Here we investigated whether systemic treatment with the S1P analog FTY720 (Fingolimod) could improve fracture healing. Twelve‐week‐old, female C57BL/6 mice received an osteotomy of the femur, which was stabilized using an external fixator. The mice received a daily subcutaneous injection of either FTY720 (6 mg/kg) or vehicle from the third postoperative day. Fracture healing was evaluated after 10 and 21 days using biomechanical testing, µ‐computed tomography, and histomorphometry. Because FTY720 is supposed to influence osteoclast recruitment, osteoclasts were identified in the fracture callus by staining for tartrate resistant acid phosphatase (TRAP). There were no significant differences in callus mechanical properties, tissue composition and osteoclast number between the groups, suggesting that systemically applied FTY720 did not influence bone regeneration in this model of regular fracture healing. Even if further studies should test the potency of FTY720 under unfavorable healing conditions, we conclude that the effect of systemically applied FTY720 on fracture healing might be inferior compared to other anabolic treatments. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1845–1850, 2013  相似文献   

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The immunosuppressive effect of FTY720 is associated with the reversible sequestration of lymphocytes from the blood and the spleen into secondary lymphoid organs and reduced egress of mature thymocytes from the thymus. This work was designed to dissect the differential effect of FTY720 on CD4 and CD8 T cell-mediated mechanisms of skin graft rejection in the presence (euthymic) or absence (thymectomized) of thymic output. To that end, untreated and FTY720-treated euthymic (Euthy) and thymectomized (ATX) mice received skin allografts across a full, class II or class I major histocompatibility complex (MHC) mismatched (MM) barriers and graft survival was monitored. We demonstrate that a short course of FTY720 treatment significantly augments the survival of full, class I and class II MHC MM skin grafts compared to the nontreated controls. Interestingly, FTY720-treated Euthy recipients showed a significantly prolonged skin allograft survival compared to FTY720-treated ATX mice. These results together show that FTY720 impairs both CD4 and CD8 T cell-mediated mechanisms of rejection and, more importantly, the presence of the thymus is necessary for the ability of FTY720 to modulate skin allograft rejection across different histocompatibility MHC barriers.  相似文献   

6.
目的 FTY720和40-氧-(2-羟乙基)-雷帕霉素(RAD)是两种新型免疫抑制剂。为评估这两种药物的效果,我们以小鼠心脏移植为模型,对比观察了这两种药物和环孢素A(CsA)对移植物存活时间的影响。方法 供体为BALB/C小鼠,受体为C57BL/6小鼠,受鼠随机分为4组,每组6只:A组空白对照;B组每日管饲CsA 10 mg/kg体重;C组每日管饲RAD 3 mg/kg体重;D组每日管饲FTY 3 mg/kg体重。各服药组均由移植当日开始喂药,至移植心停跳或术后14 d停药。结果 各组的存活天数分别为:A组6、7、8、8、9、9;B组9、9、10、11、12;C组10、12、13、13、14;D组10、12、16、16、17、18。B、C组各有1例带心死亡。所有移植心都出现程度不同的急性排斥反应征象。结论 单独使用RAD或FTY可显著延长小鼠心脏移植物的存活时间。在各所选剂量上,CsA和RAD差异无显著性(P>0.05),FTY的效果明显优于CsA和RAD。FTY和RAD是较有前途的新型免疫抑制剂。  相似文献   

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目的 探讨经冠脉灌注转化生长因子(TGF)-β1基因联合FTY720对移植心脏缺血-再灌注损伤(IRI)的影响及其机制.方法 实验分为空白对照组、空载体组、FTY720组、转基因组和转基因+FTY720组.心脏移植8 h后切取移植心脏,免疫组织化学检测mTGF-β1、ICAM-1、核转录因子(NF)-κB表达;逆转录-聚合酶链反应(RT-PCR)检测mTGF-β1 mRNA转录强度;测定超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、髓过氧化物酶(MPO)活性.结果 mTGF-β1成功转到心肌细胞,转基因组和转基因+FIY720组mTGF-β1的表达强度分别是(1.08±0.24)和(1.16±0.22),明显高于其他3组(P<0.01);而两组ICAM-1的表达积分分别是(2.43±0.46)和(1.90±0.20),NF-κB的表达积分分别是(9.80±1.85)和(10.10±2.27),较其他3组显著下调(P<0.01);FRY720组、转基因组和转基因+FTY720组心肌细胞凋亡指数分别是(9.20±1.12)、(5.90±1.09)和(5.40±0.77),显著减少(P<0.01);FTY720组、转基因组和转基因+FTY720组SOD活性分别是(51.03±5.54)、(55.91±6.66)和(73.42±6.42)U/mg,明显升高(P<0.01),MDA含量(10.90±1.93)、(11.02±2.45)和(9.28±1.64)U/g,明显下降(P<0.01);而MPO活性分别是(4.38±1.43)、(4.63±1.04)和(3.16±0.64)U/g,亦明显下降(P<0.01);转基因和FTY720两因素对减轻心肌细胞凋亡以及对SOD、MDA和MPO的影响存在交互作用(P<0.05).结论 TGF-β1和FTY720均具有减轻移植心脏缺血-再灌注损伤的作用,机制可能与抑制心肌细胞凋亡、下调ICAM-1、NF-κB表达、增高SOD活性等因素有关;两者联合应用在减轻缺血-再灌注损伤方面有协同作用.  相似文献   

8.
Abstract The novel immunosuppressive compound FTY 720A posseses a mode of action which is different from all other immunosuppressive drugs. The most prominent feature is a reversible decrease in peripheral lymphocyte counts observed in animal experiments. We investigated in the first human trial (phase 1) whether FTY 720A induces apoptosis of peripheral blood mononuclear cells (PBMC) in stable renal allograft recipients. Monitoring of lymphocyte counts revealed a significant and dose‐dependent decrease within 6 h post‐FTY 720A dose: placebo 5.1%; 0.25 mg 36.4%; 0.5 mg 40.8%; 0.75 mg 39.4%; 1 mg 45.8%; 2 mg 67.2%; 3.5 mg 64.9%. PBMC apoptosis rates did not change, as determined before intake of FTY 720A and 2 h, 6 h, 24 h and 96 h post‐FTY 720A dose. We detected no significant difference in apoptosis rates between patients who received placebo or FTY 720A. However, in vitro experiments showed that high concentrations of FTY 720 A induced apoptosis in human PBMC.  相似文献   

9.
目的 将供、受者骨髓细胞经混合培养后过继回输,以观察其对同种异体移植心脏存活时间和受者免疫功能的影响.方法 取Balb/c小鼠和C57BL/6J小鼠的骨髓细胞,进行混合培养.配制含Balb/c小鼠和C57BL/6J小鼠脾淋巴细胞的混合淋巴细胞反应体系(MLR)以及含Balb/c小鼠和C3H小鼠脾淋巴细胞的MLR,分别加入混合培养的骨髓细胞,观察其对MLR中细胞增殖的影响.以C57BL/6J小鼠为供者,Balb/c小鼠为受者行腹腔异位心脏移植,实验分为4组:(1)移植对照组,受者仅进行心脏移植,不作其他处理;(2)实验对照组,心脏移植后给予西罗莫司灌胃;(3)实验组,移植手术结束前注射混合培养的骨髓细胞1×10~7个,术后给予西罗莫司;(4)第三方对照组,受者接受C3H小鼠的移植心脏,手术结束前注射混合培养的骨髓细胞1×10~7个,术后给予西罗莫司.记录移植心脏存活时间;移植心脏停跳当日,取受者外周血,检测CD4~+ CD25~+ T淋巴细胞的比例及供者来源的H-2K~b细胞的比例.结果 加入混合培养的骨髓细胞后,Balb/c和C57BL/6J的MLR的淋巴细胞增殖率低于Balb/c和C3H的MLR.实验组移植心脏的存活时间长于其他3组(P<0.05).实验组CD4~+CD25~+T淋巴细胞的百分率高于其他3组(P<0.05).实验组外周血中H-2K~b细胞的比例高于其他3组(P<0.05).结论 受者输注混合培养的供、受者骨髓细胞可在一定程度上调节免疫应答,延长小鼠移植心脏的存活时间,该作用具有供者抗原特异性.  相似文献   

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Recognition of evolutionarily conserved ligands by Toll‐like receptors (TLRs) triggers signaling cascades in innate immune cells to amplify adaptive immune responses. Nearly all TLRs require MyD88 to transduce downstream signaling. MyD88 deficiency has been shown to promote the allograft acceptance in mice. However, direct evidence for therapeutic potential of MyD88 inhibitors remains lacking. Herein, we used a MyD88 inhibitor, namely ST2825, to explore its therapeutic potential and mechanisms in fully allogeneic skin and heart transplant models. Phenotypic maturation of dendritic cells stimulated by TLR ligands was alleviated by ST2825 in parallel with reduced T‐cell proliferation in vitro. A short‐course treatment with ST2825 significantly prolonged cardiac graft survival (mean survival time = 18.5 ± 0.92 days vs. 7.25 ± 0.46 days). ST2825‐treated group had significantly reduced proinflammatory cytokines in allografts compared with control group. ST2825 combined with anti‐CD154 induced long‐term skin allograft acceptance in about one‐third of recipients (>100 days). ‘Skin‐tolerant’ recipients showed attenuated donor‐specific IFN‐γ responses, intact IL‐4 responses, and compromised alloantibody responses. We conclude that MyD88 inhibitor ST2825 attenuates acute cardiac rejection and promotes donor‐specific hyporesponsiveness in stringent skin transplant models. The direct evidence suggests that pharmacological inhibition of MyD88 hold promising potential for transplant rejection.  相似文献   

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目的 探讨吞噬供体凋亡细胞的受者树突状细胞 (DC)的功能及其在诱导同种异体小鼠心脏移植耐受中的作用。方法 应用中波紫外线照射的方法诱导供者脾细胞凋亡 ,并在体外与受者骨髓来源的DC共同培养 ,同时用核因子 κB寡聚脱氧核苷酸诱骗剂 (NF κBODNDecoy)抑制DC的成熟。建立同种异体小鼠心脏异位移植模型 ,移植术前 7d经门静脉给受者输注经上述处理的DC ,观察移植物的存活时间 ,并检测移植物内相关细胞因子基因的表达情况。结果 NF κBODNDecoy可明显抑制DC吞噬凋亡细胞后的成熟 ;经NF κBODNDecoy处理且负载凋亡脾细胞的DC可抑制T淋巴细胞增殖反应 ,且具有供者特异性 ,接受DC门静脉输注的受者 ,移植心脏的平均存活时间明显延长 ,移植心脏内白细胞介素 2及γ干扰素mRNA的水平减低 ,白细胞介素 10mRNA的水平升高 ,而输注仅负载凋亡脾细胞的DC ,移植心脏的平均存活时间未见延长 (P <0 .0 1) ,这种保护作用具有抗原特异性。结论 以NF κBODNDecoy处理的、吞噬同种凋亡细胞的受者未成熟DC可明显延长同种小鼠移植心脏的存活时间。  相似文献   

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Donor‐specific immunological tolerance using high doses of bone marrow cells (BMCs) has been demonstrated in mixed chimerism‐based tolerance induction protocols; however, the development of graft versus host disease remains a risk. Here, we demonstrate that the co‐infusion of limited numbers of donor unfractionated BMCs with human amnion‐derived multipotent progenitor cells (AMPs) 7 days post–allograft transplantation facilitates macrochimerism induction and graft tolerance in a mouse skin transplantation model. AMPs + BMCs co‐infusion with minimal conditioning led to stable, mixed, multilineage lymphoid and myeloid macrochimerism, deletion of donor‐reactive T cells, expansion of CD4+CD25+Foxp3+ regulatory T cells (Tregs) and long‐term allograft survival (>300 days). Based on these findings, we speculate that AMPs maybe a pro‐tolerogenic cellular therapeutic that could have clinical efficacy for both solid organ and hematopoietic stem cell transplant applications.  相似文献   

18.
目的 研究经他克莫司(Tac)处理的供者未成熟树突状细胞(imEX3)在延长大鼠移植心脏存活时间中的作用和机制.方法 以Wistar大鼠为供者,SD大鼠为受者,行颈部异位心脏移植.心脏移植前将受者随机分为3组,每组15只,进行不同的预处理.第1组:为对照组,术前7 d经受者的尾静脉注射生理盐水1.0ml;第2组:为未经Tac处理组,术前7 d经受者的尾静脉注射未经Tac处理的imDC 2×106(1.0 m1);第3组:为Tac处理组,术前7 d经受者的尾静脉注射经Tac处理的imDC 2×106(1.0 m1).术后观察:移植心脏的存活时间、受者与供者及无关供者(Lewis大鼠)的单向混合淋巴细胞反应(MLR)、心肌组织病理学表现及血清中白细胞介素(IL)-2、IL-4、IL-10和γ干扰素(IFN-γ)的水平变化.结果 第1、2、3组移植心脏的存活时间分别为(8.57±1.34)d、(20.92±2.68)d和(33.30±3.92)d.各组之间比较,差异均有统计学意义(P<0.01);第2、3组受者对供者的MLR刺激指数较第1组明显降低,而对无关供者的MLR刺激指数则与第1组相近;各组受者血清IL-2、IFN-γ、IL-4、IL-10浓度问差异有统计学意义(P<0.01),第3组IL-2和IFN-γ(代表TH1细胞)水平明显降低,而IL-4和IL-10(代表TH2细胞)水平明显增高.结论 imDC能够延长大鼠心脏移植后的存活时间,经Tac处理的imDC能够进一步加强这种作用;且imDC所诱导的免疫低反应性是供者特异性的.其机制可能主要与调节T淋巴细胞免疫应答类型(TH1至TH2的免疫偏移)和诱导T淋巴细胞免疫应答降低有关.  相似文献   

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The method of constructing cartilage tissue from bone marrow‐derived cells in vitro is considered a valuable technique for hyaline cartilage regenerative medicine. Using a rotating wall vessel (RWV) bioreactor developed in a NASA space experiment, we attempted to efficiently construct hyaline cartilage tissue from human bone marrow‐derived cells without using a scaffold. Bone marrow aspirates were obtained from the iliac crest of nine patients during orthopedic operation. After their proliferation in monolayer culture, the adherent cells were cultured in the RWV bioreactor with chondrogenic medium for 2 weeks. Cells from the same source were cultured in pellet culture as controls. Histological and immunohistological evaluations (collagen type I and II) and quantification of glycosaminoglycan were performed on formed tissues and compared. The engineered constructs obtained using the RWV bioreactor showed strong features of hyaline cartilage in terms of their morphology as determined by histological and immunohistological evaluations. The glycosaminoglycan contents per µg DNA of the tissues were 10.01 ± 3.49 µg/µg DNA in the case of the RWV bioreactor and 6.27 ± 3.41 µg/µg DNA in the case of the pellet culture, and their difference was significant. The RWV bioreactor could provide an excellent environment for three‐dimensional cartilage tissue architecture that can promote the chondrogenic differentiation of adult human bone marrow‐derived cells. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 517–521, 2009  相似文献   

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目的探讨核因子κB(NF-κB)诱骗剂处理供者树突状细胞(DC)对同种异体小鼠移植心脏存活时间的影响。方法在体外以NF-κB诱骗剂处理供者骨髓来源的DC,并于心脏移植术前7d经门静脉输注2×10^6个DC给受者,术后1~7d受者接受亚治疗量的环孢素A(10mg·kg^-1·d^-1)腹腔注射(联合方案组),并设不作任何处理(对照组)、单用环孢素A(CsA组)、单纯输注未经处理DC(DC对照组)和单纯输注经处理DC(DC实验组)的对照组,另设接受来自第三方供者的对照组(第三供者组,受者的处理同联合方案组),所有受者均接受腹腔心脏移植。观察各组移植心脏的存活时间;采用酶联免疫吸附法检测术后第7天受者血清白细胞介素2(IL-2)、IL-4、IL-10和γ干扰素(IFN-γ)的含量。结果移植心脏平均存活时间(MST),对照组为7d,CsA组为10.3d,DC对照组为7.6d,DC实验组为21.4d,联合方案组为53.6d,第三供者组为9d,DC实验组移植心脏MST明显长于对照组和DC对照组,差异有统计学意义(P〈0.01);联合方案组移植心脏MST明显长于CsA组、DC实验组及第三供者组,差异有统计学意义(P〈0.01)。联合方案组IL-2和IFN-γ的含量最低,而IL-4和IL-10的含量最高,与其它各组比较,差异均有统计学意义(P〈0.05);与对照组、DC对照组及CsA组相比,DC实验组IL-2及IFN-γ的含量也显著降低(P〈0.05),而IL-4和IL-10则升高(P〈0.05)。结论术前输注经NF-κB诱骗剂处理的供者DC可延长同种小鼠移植心脏的存活时间,若术后加用短程亚治疗量CsA,则移植心脏的存活时间得到进一步延长。  相似文献   

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