1磷酸鞘氨醇及其G蛋白偶联受体的免疫调节功能研究进展

1磷酸鞘氨醇（sphingosine—l—phosphate，S1P）是一种具有重要生物学活性的溶血磷脂，它作为第一信使与各种免疫细胞膜上相应的G蛋白偶联受体相互作用发挥不同的免疫调节功能。S1P可抑制T细胞的增殖，并抑制活化的CD4^＋ T细胞分泌IFN-γ和IL-4。SIP对T细胞、B细胞、树突状细胞和NK细胞都具有趋化性，其主要效应是通过其受体SIP1介导调节淋巴细胞再循环和组织分布。S1P对调节性T细胞趋化性弱，是调节性T细胞发挥最佳活性所必需的。新型免疫抑制剂FFY720进入人体后快速磷酸化，形成具有生物学活性的FFY720-P，与SIP相似，是其受体S1P1、S1P3、S1P。和S1P，的真正激动剂，可影响成熟T细胞、B细胞、树突状细胞及调节性T细胞的组织分布与功能活性，具有低毒高效可逆的免疫抑制效应，能够预防异体移植物排斥及治疗自身免疫病。本文就S1P的合成、代谢及其G蛋白偶联受体在免疫细胞的表达、对各种免疫细胞的影响、以S1PGPCRs为靶点的药物及其临床意义进行综述。     

Brain penetration of the oral immunomodulatory drug FTY720 and its phosphorylation in the central nervous system during experimental autoimmune encephalomyelitis: consequences for mode of action in multiple sclerosis

FTY720 [2-amino-2-[2-(4-octylphenyl) ethyl]propane-1,3-diol hydrochloride] is an oral sphingosine-1-phosphate receptor modulator under development for the treatment of multiple sclerosis (MS). The drug is phosphorylated in vivo by sphingosine kinase 2 to its bioactive form, FTY720-P. Although treatment with FTY720 is accompanied by a reduction of the peripheral lymphocyte count, its efficacy in MS and experimental autoimmune encephalomyelitis (EAE) may be due to additional, direct effects in the central nervous system (CNS). We now show that FTY720 localizes to the CNS white matter, preferentially along myelin sheaths. Brain trough levels of FTY720 and FTY720-P in rat EAE are of the same magnitude and dose dependently increase; they are in the range of 40 to 540 ng/g in the brain tissue at efficacious doses and exceed blood concentrations severalfold. In a rat model of chronic EAE, prolonged treatment with 0.03 mg/kg was efficacious, but limiting the dosing period failed to prevent EAE despite a significant decrease in blood lymphocytes. FTY720 effectiveness is likely due to a culmination of mechanisms involving reduction of autoreactive T cells, neuroprotective influence of FTY720-P in the CNS, and inhibition of inflammatory mediators in the brain.     

1-磷酸鞘氨醇对T细胞功能的影响

1-磷酸鞘氨醇（S1P）是鞘磷脂代谢过程中产生的一种重要信号分子，可与多条信号通路交联而产生广泛的生物学效应。T细胞表达5种S1P受体，即S1P1—S1P5。S1P信号可以调节T细胞的多种免疫效应，包括T细胞增殖和凋亡、T细胞向Th2细胞分化、细胞因子分泌及T细胞迁移等。抑制S1P信号通路的药物FTY720可将T细胞阻滞于次级淋巴器官，造成外周血T细胞显著减少而发挥强烈的免疫抑制作用。本文对S1P的合成和降解、S1P受体及其介导的信号途径、T细胞S1P受体的表达、S1P对T细胞功能的调节及S1P信号通路的免疫抑制药物作了概述．     

FTY720 stimulates multidrug transporter- and cysteinyl leukotriene-dependent T cell chemotaxis to lymph nodes

FTY720 is a sphingosine-derived immunosuppressant. Phosphorylated FTY720 promotes T cell homing from spleen and peripheral blood to LNs by acting as an agonist for sphingosine-1-phosphate (S1P) receptors. Here we demonstrate that FTY720 enhances the activity of the sphingosine transporter Abcb1 (Mdr1) and the leukotriene C(4) transporter Abcc1 (Mrp1). Both transporters must be active for FTY720-mediated T cell migration and LN homing. Migration and homing driven by FTY720, phosphorylated FTY720, or S1P also require 5-lipoxygenase-mediated synthesis of cysteinyl leukotrienes and their efflux from the cell. FTY720-mediated LN homing events further downstream are dependent on CCL19, CCL21, VLA-4alpha, and CD44. Use of T cells deficient in 5-lipoxygenase, Abcb1, and Abcc1, and comparison of the effects of FTY720 with those of S1P, suggest a model of sequential engagement of Abcb1, SP1 receptors, 5-lipoxygenase, and Abcc1 to enhance T cell migration and homing.     

Sphingosine-1-phosphate and FTY720 as anti-atherosclerotic lipid compounds

All stages of atherosclerosis have been identified as a chronic vascular inflammatory disease. In the last few years there is increasing evidence that endogenous lysophospholipids such as sphingosine-1-phosphate (S1P) have potent anti-inflammatory properties. The S1P analogue FTY720 that has been developed as a potent, orally active, immunosuppressant in the field of transplantation and autoimmune disease has interesting effects on inflammatory processes in the arterial vessel wall. S1P targets five specific S1P receptors (S1P(1-5)), which are ubiquitously expressed. S1P(1-3) receptor expression is identified in arterial vessels. S1P and FTY720 show potent silencing effects on some vascular proinflammatory mechanisms in endothelial and vascular smooth muscle cells. In addition, the interaction of monocytes with the vessel wall is inhibited. As shown recently, FTY720 can effectively reduce the progression of atherosclerosis in apolipoprotein E-deficient mice having a high-cholesterol diet. It is not entirely clear which S1P receptor subtype is mainly involved in this process. However, it is currently speculated that the S1P(3) and probably the S1P(1) is involved in the anti-atherosclerotic effects of FTY720. This review summarizes the current knowledge about S1P- and FTY720-effects on mechanisms of vascular inflammatory disease. In addition S1P receptor subtypes are identified which might be interesting for molecular drug targeting.     

FTY720对小鼠胸腺淋巴细胞的影响

目的 FTY720是将冬虫夏草抽提物中具有免疫抑制作用的成分ISP-Ⅰ进行结构改造而成的新型免疫抑制剂,研究目的是明确FTY720对于小鼠胸腺淋巴细胞的影响。方法利用MTT比色法和DNA Ladder两种方法检测经过FTY720处理后的小鼠胸腺细胞的活性。没2h,4h,6h三个时间对照;0．5mg／mL,1mg／mL,2mg／mL三个浓度对照。并对MTT法用F-检验双样本方差分析,t-检验双样本等方差假设两种统计学方法检验结果。对DNA Ladder法直接观察凋亡条带。结果不同浓度FTY720作用过的小鼠胸腺细胞活性有差异,浓度越高活性越低;同一浓度作用不同时间后,细胞活性也有差异,时间越长活性越低。     

Local application of FTY720 to the lung abrogates experimental asthma by altering dendritic cell function

Airway DCs play a crucial role in the pathogenesis of allergic asthma, and interfering with their function could constitute a novel form of therapy. The sphingosine 1-phosphate receptor agonist FTY720 is an oral immunosuppressant that retains lymphocytes in lymph nodes and spleen, thus preventing lymphocyte migration to inflammatory sites. The accompanying lymphopenia could be a serious side effect that would preclude the use of FTY720 as an antiasthmatic drug. Here we show in a murine asthma model that local application of FTY720 via inhalation prior to or during ongoing allergen challenge suppresses Th2-dependent eosinophilic airway inflammation and bronchial hyperresponsiveness without causing lymphopenia and T cell retention in the lymph nodes. Effectiveness of local treatment was achieved by inhibition of the migration of lung DCs to the mediastinal lymph nodes, which in turn inhibited the formation of allergen-specific Th2 cells in lymph nodes. Also, FTY720-treated DCs were intrinsically less potent in activating naive and effector Th2 cells due to a reduced capacity to form stable interactions with T cells and thus to form an immunological synapse. These data support the concept that targeting the function of airway DCs with locally acting drugs is a powerful new strategy in the treatment of asthma.     

Characterization of a sphingosine 1-phosphate receptor antagonist prodrug

Sphingosine 1-phosphate (S1P) is a phospholipid that binds to a set of G protein-coupled receptors (S1P(1)-S1P(5)) to initiate an array of signaling cascades that affect cell survival, differentiation, proliferation, and migration. On a larger physiological scale, the effects of S1P on immune cell trafficking, vascular barrier integrity, angiogenesis, and heart rate have also been observed. An impetus for the characterization of S1P-initiated signaling effects came with the discovery that FTY720 [fingolimod; 2-amino-2-(2-[4-octylphenyl]ethyl)-1,3-propanediol] modulates the immune system by acting as an agonist at S1P(1). In the course of structure-activity relationship studies to better understand the functional chemical space around FTY720, we discovered conformationally constrained FTY720 analogs that behave as S1P receptor type-selective antagonists. Here, we present a pharmacological profile of a lead S1P(1/3) antagonist prodrug, 1-(hydroxymethyl)-3-(3-octylphenyl)cyclobutane (VPC03090). VPC03090 is phosphorylated by sphingosine kinase 2 to form the competitive antagonist species 3-(3-octylphenyl)-1-(phosphonooxymethyl)cyclobutane (VPC03090-P) as observed in guanosine 5'-O-(3-[(35)S]thio)triphosphate binding assays, with effects on downstream S1P receptor signaling confirmed by Western blot and calcium mobilization assays. Oral dosing of VPC03090 results in an approximate 1:1 phosphorylated/alcohol species ratio with a half-life of 30 h in mice. Because aberrant S1P signaling has been implicated in carcinogenesis, we applied VPC03090 in an immunocompetent mouse mammary cancer model to assess its antineoplastic potential. Treatment with VPC03090 significantly inhibited the growth of 4T1 primary tumors in mice. This result calls to attention the value of S1P receptor antagonists as not only research tools but also potential therapeutic agents.     

Fingolimod attenuates renal ischemia/reperfusion-induced acute lung injury by inhibiting inflammation and apoptosis and modulating S1P metabolism

ObjectiveThis study examined whether the immunomodulator fingolimod (FTY720) could alleviate renal ischemia/reperfusion (I/R)-induced lung injury and explored the potential mechanisms.MethodsRenal I/R was established in a rat model, and FTY720 (0.5, 1, or 2 mg/kg) was injected intraperitoneally after 15 minutes of ischemia. Pro-inflammatory cytokine levels, oxidative stress, apoptosis, and the mRNA expression of the sphingosine-1-phosphate (S1P)-related signaling pathway genes sphingosine kinase-1 (SphK1) and sphingosine kinase-2 were analyzed in lung tissue.ResultsIncreased pro-inflammatory cytokine levels; decreased total superoxide dismutase, catalase, and glutathione peroxidase levels; increased apoptosis; and increased S1P lyase and SphK1 expression were observed following renal I/R. FTY720 reversed renal I/R-induced changes and effectively attenuated lung injury.ConclusionFTY720 protected against acute lung injury in rats subjected to renal I/R by decreasing pulmonary inflammation and apoptosis, increasing oxidative stress, and modulating S1P metabolism.     

The immunomodulator FTY720 has a direct cytoprotective effect in oligodendrocyte progenitors

The immunomodulator 2-amino-2-[2-(4-octylphenyl)ethyl]-1,3-propanediol (FTY720) has promising therapeutic effects in multiple sclerosis (MS), a degenerative disease in which demyelination of the central nervous system is accompanied by death of oligodendrocytes (OLGs), the myelin-producing cells. In vivo phosphorylation of FTY720 generates an agonist for G protein-coupled receptors for sphingosine-1-phosphate, a lipid mediator that plays a crucial role in the stimulation of OLG survival by neurotrophin-3 (NT-3). The mechanisms underlying the action of FTY720 in MS are not clearly understood, although the effects of this drug in autoimmune diseases are thought to stem from its ability to reduce lymphocyte infiltration and inflammation. Interestingly, we now found that FTY720 also has a direct effect on OLG progenitors. Treatment of these cells with FTY720 causes activation of extracellular signal-regulated kinase 1/2 and Akt, accompanied by protection from apoptosis. However, FTY720 also arrested OLG differentiation. Importantly, this effect was counteracted by NT-3, which not only enhanced the survival of OLG progenitors induced by FTY720 but also stimulated their maturation. Altogether, these observations suggest that in addition to its immunosuppressive functions, FTY720 could also have a beneficial effect in MS by direct action on OLG progenitors. However, the finding that FTY720 blocks the differentiation of these cells raises the question of whether MS therapies with FTY720 should include the use of differentiation-enhancing factors such as NT-3. This approach would ensure both protection of existing OLG progenitor pools against immune-mediated insults as well as stimulation of remyelination by enhancing the maturation of these cells.     

Sphingosine-1-phosphate-induced airway hyper-reactivity in rodents is mediated by the sphingosine-1-phosphate type 3 receptor

There is a need to better understand the mechanism of airway hyper-reactivity, a key feature of asthma. Evidence suggests that sphingosine-1-phosphate (S1P) could be a major player in this phenomenon. The purpose of this work was to define the S1P receptor responsible for this phenomenon. We have studied, in the rat, the effect of two S1P synthetic receptor ligands, 2-amino-2-[2-(4-octylphenyl)ethyl]propane-1,3-diol (FTY720) (which in its phosphorylated form is a potent agonist at each S1P receptor except S1P(2)) and 3-[[2-[4-phenyl-3-(trifluoromethyl)phenyl]-1-benzothiophen-5-yl]methylamino]propanoic acid (AUY954) (a selective S1P(1) agonist) on lung function in vivo. This was complemented by in vitro studies using isolated trachea from the rat, the S1P(3) receptor-deficient mouse, and its wild-type counterpart. After oral administration, FTY720 induced a generalized airway hyper-reactivity to a range of contractile stimuli. This was observed as early as 1 h postdosing, lasted for at least 24 h, and was not subject to desensitization. In both rat and wild-type mouse isolated trachea, preincubation with the active phosphorylated metabolite of FTY720 induced hyper-responsiveness to 5-hydroxytryptamine. This effect was not seen in the isolated tracheas from S1P(3) receptor-deficient mice. AUY954, did not mimic the effect of FTY720 either in vivo or in vitro. Our data are consistent with activation of the S1P pathway inducing a generalized airway hyper-reactivity in rats and mice that is mediated by the S1P(3) receptor. S1P(3) receptor antagonists might prove to be useful as new therapeutic strategies aimed at blocking the airway hyper-reactivity observed in asthma.     

Clinical views from the forefront of immunosuppressive drugs

Recently, many immunosuppressants have been developed and some of them have already been introduced in clinical organ transplantation. With a new concept of immunoregulation, which focuses on prevention of rejection and over-immunosuppression, the latest protocol has been conducted. Chimeric or humanized antibodies targeting the lymphocyte surface molecule such as CD19, 20, 25, 40, and 52 are administrated in the induction phase, and calcineurin inhibitors (cyclosporin and tacrolimus) are used as key drugs. For tapering the doses of them, the combined application of anti-metabolic agents of azathioprine, mizoribine, or mycophenolate mofetil (MMF) has been proved effective. Lymphocyte forming drugs induce unique immunoregulation, targeting at sphingosine 1-phosphate (SlP) receptors. FTY720 is now in the procedure of clinical trial to compare with MMF. KRP203 is also a candidate for more specific SIP receptor agonist. In this issue, I reviewed the recent immunosuppressive strategy and focused on the advance of novel immunosuppressive drugs.     

FTY720: A new kid on the block for transplant immunosuppression

FTY720, a synthetic analogue of myriocin (ISP-1), is derived from culture filtrates of the fungus Isaria sinclairii. As a sphingosine analogue, FTY720 appears to undergo phosphorylation and thereby interact with specific G-protein-linked receptors. In vivo, FTY720 causes emigration of lymphocytes from peripheral blood to secondary lymphoid structures. Thus, the drug is the archetype of a new class of agents that alter cellular homing patterns: the adhesion-migration paradigm. Since FTY720 seems to spare nonspecific elements of host resistance, it may address the not infrequent complications of infections associated with existing therapies. In experimental rodent, canine and non-human primate models, FTY720 produces lymphopenia and immunosuppression, prolonging the survival of allografts. Because of synergistic interactions, it promotes the immunosuppressive effects not only of calcineurin antagonists, but also of proliferation signal inhibitors. These interactions proffer the possibility of large reductions in exposure to and mitigated toxicity of existing drugs. In humans, FTY720 causes dose-dependent peripheral blood lymphopenia, a reduced incidence of acute rejection episodes and only one apparent adverse reaction - a negative chronotropic effect - particularly after the loading dose. While the clinical utility of FTY720 is difficult to predict before completion of Phase III studies that elucidate its benefits versus unanticipated side effects, the initial data suggest several potential advantages: it does not produce hyperlipidaemia, diabetes mellitus, nephrotoxicity, neurotoxicity or myelosuppression, which are characteristic of other immunosuppressants. Furthermore, it displays high oral bioavailability and a low interindividual coefficient of variation. Clearly, structural analogues, as well as other agents that alter the balance of chemokines or affect cellular adhesion to activated endothelium, will represent important components of future regimens.     

FTY720: A new kid on the block for transplant immunosuppression

FTY720, a synthetic analogue of myriocin (ISP-1), is derived from culture filtrates of the fungus Isaria sinclairii. As a sphingosine analogue, FTY720 appears to undergo phosphorylation and thereby interact with specific G-protein-linked receptors. In vivo, FTY720 causes emigration of lymphocytes from peripheral blood to secondary lymphoid structures. Thus, the drug is the archetype of a new class of agents that alter cellular homing patterns: the adhesion–migration paradigm. Since FTY720 seems to spare nonspecific elements of host resistance, it may address the not infrequent complications of infections associated with existing therapies. In experimental rodent, canine and non-human primate models, FTY720 produces lymphopenia and immunosuppression, prolonging the survival of allografts. Because of synergistic interactions, it promotes the immunosuppressive effects not only of calcineurin antagonists, but also of proliferation signal inhibitors. These interactions proffer the possibility of large reductions in exposure to and mitigated toxicity of existing drugs. In humans, FTY720 causes dose-dependent peripheral blood lymphopenia, a reduced incidence of acute rejection episodes and only one apparent adverse reaction – a negative chronotropic effect – particularly after the loading dose. While the clinical utility of FTY720 is difficult to predict before completion of Phase III studies that elucidate its benefits versus unanticipated side effects, the initial data suggest several potential advantages: it does not produce hyperlipidaemia, diabetes mellitus, nephrotoxicity, neurotoxicity or myelosuppression, which are characteristic of other immunosuppressants. Furthermore, it displays high oral bioavailability and a low interindividual coefficient of variation. Clearly, structural analogues, as well as other agents that alter the balance of chemokines or affect cellular adhesion to activated endothelium, will represent important components of future regimens.     

The selective sphingosine 1-phosphate receptor 1 agonist ponesimod protects against lymphocyte-mediated tissue inflammation

Lymphocyte exit from lymph nodes and their recirculation into blood is controlled by the sphingolipid sphingosine 1-phosphate (S1P). The cellular receptor mediating lymphocyte exit is S1P(1), one of five S1P receptors. Nonselective agonists for S1P receptors lead to blood lymphocyte count reduction. The effects of selective S1P(1) agonists on blood lymphocyte count and their impact in models of lymphocyte-mediated tissue inflammation have been less investigated. We describe here the general pharmacology of ponesimod, (Z,Z)-5-[3-chloro-4-((2R)-2,3-dihydroxy-propoxy)-benzylidene]-2-propylimino-3-o-tolyl-thiazolidin-4-one, a new, potent, and orally active selective S1P(1) agonist. Ponesimod activated S1P(1)-mediated signal transduction with high potency (EC(50) of 5.7 nM) and selectivity. Oral administration of ponesimod to rats led to a dose-dependent decrease of blood lymphocyte count. After discontinuation of dosing, blood lymphocyte count returned to baseline within 48 h. Ponesimod prevented edema formation, inflammatory cell accumulation, and cytokine release in the skin of mice with delayed-type hypersensitivity. Ponesimod also prevented the increase in paw volume and joint inflammation in rats with adjuvant-induced arthritis. These data show that selective activation of S1P(1) using ponesimod leads to blood lymphocyte count reduction and efficacy in models of lymphocyte-mediated tissue inflammation. Immunomodulation with a rapidly reversible S1P(1)-selective agonist may represent a new therapeutic approach in lymphocyte-mediated autoimmune diseases.     

Development of small-molecule inhibitors of sphingosine-1-phosphate signaling

The pleiotropic sphingolipid mediator, sphingosine-1-phosphate, produced in cells by two sphingosine kinase isoenzymes, SphK1 and SphK2, regulates many cellular and physiological processes important for homeostasis and development and pathophysiology. Many of the actions of S1P are mediated by a family of five specific cell surface receptors that are ubiquitously and specifically expressed, although important direct intracellular targets of S1P have also recently been identified. S1P, SphK1, and or S1P receptors have been linked to onset and progression of numerous diseases, including many types of cancer, and especially inflammatory disorders, such as multiple sclerosis, asthma, rheumatoid arthritis, inflammatory bowel disease, and sepsis. S1P formation and signaling are attractive targets for development of new therapeutics. The effects of a number of inhibitors of SphKs and S1PRs have been examined in animal models of human diseases. The effectiveness of the immunosuppressant FTY720 (known as Fingolimod or Gilenya), recently approved for the treatment of multiple sclerosis, whose actions are mediated by downregulation of S1PR1, has become the gold standard for S1P-centric drugs. Here, we review S1P biology and signaling with an emphasis on potential therapeutic benefits of specific interventions and discuss recent development of small molecule antagonists and agonists that target specific subtypes of S1P receptors as well as inhibitors of SphKs.     

Graft-versus-host disease can be separated from graft-versus-lymphoma effects by control of lymphocyte trafficking with FTY720

Graft-versus-host disease (GvHD) mediated by donor T cells recognizing host alloantigens is associated with beneficial graft-versus-tumor effects in recipients of allogeneic hematopoietic cell transplants. Since leukemias and lymphomas reside largely within the lymphohematopoietic system, we have proposed that the desired graft-versus-leukemia or graft-versus-lymphoma effect can be separated from the complication of GvHD by confinement of the graft-versus-host alloresponse to the lymphohematopoietic tissues. Since the new sphingosine-1-phosphate receptor agonist immunosuppressive drug FTY720 leads to trapping of T cells in secondary lymphoid tissues, we evaluated the possibility that this drug could diminish GvHD, a disease involving epithelial target tissues, while permitting a beneficial alloresponse to take place within the lymphohematopoietic system, leading to graft-versus-lymphoma effects. We demonstrate here that FTY720 markedly reduces GvHD in a clinically relevant, haploidentical strain combination, while permitting antitumor effects against a T cell lymphoma of unshared host MHC haplotype to proceed unhindered. These results establish a potential new immunotherapeutic approach to separating graft-versus-leukemia effects from GvHD.     

Distinct pathways of apoptosis triggered by FTY720, etoposide, and anti-Fas antibody in human T-lymphoma cell line (Jurkat cells)

2-amino-2-[2-(4-octylphenyl)ethyl] propane-1,3-diol hydrochloride (FTY720), a synthetic product derived from a metabolite of Isaria sinclairii, has been demonstrated to have a potent immunosuppressive activity that induces apoptotic cell death in T cells and several other cell lines. In this study, using the human T-lymphoma cell line, Jurkat cells, we investigated the apoptotic signal transduction mediated by FTY720, in particular comparing its role on the cleavage of caspases, with that mediated by etoposide or anti-Fas antibody. All of these agents cleaved caspases, inducing their active form in the affected cells. Pretreatment with a broad caspase inhibitor [benzyloxycarbonyl-Val-Ala-Asp-(Ome) fluoromethyl ketone] markedly decreased the incidence of apoptotic cells induced by FTY720, etoposide, and anti-Fas antibody, through the abrogation of cleavage of Bid, poly(ADP-ribose) polymerase, and caspases 3, 8, and 9. The overexpression of Bcl-2 gene prevented FTY720- and etoposide-mediated apoptosis, but not Fas-mediated apoptosis. In addition, mitochondria were demonstrated to play a critical role in FTY720-triggered cell death, suggesting that this drug has a potent anticancer activity.     

鞘氨醇-1-磷酸酯受体拮抗剂对抗肾小球基底膜肾炎的影响

目的观察鞘氨醇-1-磷酸酯受体拮抗剂720(sphingosine-1-phosphate receptor agonist 720,FTY720)对C57BL/6小鼠抗肾小球基底膜肾炎模型(Anti-GBM GN)的干预作用并对其作用机制进行探讨。方法选择健康雄性C57BL/6小鼠52只,给予兔IgG(500μg)加完全弗氏佐剂皮下注射进行预免疫,5d后从中随机抽取8只作为正常对照组,经尾静脉注射同剂量的非抗体性的正常兔血清,其余44只小鼠取灭活兔抗小鼠GBM抗血清0.3mL/20g经尾静脉注射。44只小鼠按随机化原则分组,FTY0.3mg/(kg·d)组(n=8)尾静脉注射6h后0.3mg/(kg·d)FTY720灌胃;FTY3mg/(kg·d)组(n=8)3mg/(kg·d)FTY720灌胃;FTY5mg/(kg·d)组(n=8)5mg/(kg·d)FTY720灌胃;FTY10mg/(kg·d)组(n=8)10mg/(kg·d)FTY720灌胃;Anti-GBM GN组(n=12)为模型组,同等剂量的无菌生理盐水灌胃。观察小鼠实验室指标及肾脏组织病理学改变情况。实时定量PCR检测小鼠脾脏鞘氨醇-1-磷酸脂(sphingosine-1-phosphate,S1P)受体S1P1～S1P5mRNA表达变化。流式细胞仪检测CD4+T细胞的凋亡情况。结果治疗组小鼠的尿蛋白、血肌酐、尿素氮和血胆固醇水平明显降低,血浆白蛋白明显增高;治疗组小鼠肾脏组织学病变明显减轻。与模型组相比,用药各组随着用药剂量增加S1P1、S1P2、S1P5的表达量逐渐减少,差异有显著性;S1P3、S1P4的表达量无明显变化,差异无显著性。流式细胞仪检测结果表明FTY720促进小鼠脾脏CD4+T细胞凋亡。结论 FTY720可能通过下调S1P1、S1P2、S1P5mRNA表达,促进CD4+T细胞凋亡,减轻抗肾小球基底膜肾炎模型的肾脏组织学改变,从而减少蛋白尿、稳定肾功能。