CNI induced Th17/Treg imbalance and susceptibility to renal dysfunction in renal transplantation

Calcineurin inhibitors (CNI) prevent graft rejection by blocking interleukin-2 (IL-2), which was required for development and function of Foxp3⁺CD4⁺CD25⁺ regulatory T cells (Treg). Recently, IL-2 was reported to play a part in the inhibition of Th17 cells. The renal transplantation recipient who used CNI regularly might have Th17/Treg imbalance with increased Th17 cells and decreased Treg cells, which would cause renal dysfunction even rejection. To assess the effect of CNI on Th17 cells and Treg cells, we included 123 renal transplantation recipients (101 in a stable stage and 22 with renal dysfunction) and 27 healthy volunteers. Among all the recipients, 103 recipients used CNI and 20 recipients used sirolimus without CNI. The recipients who used CNI were further classified into four groups according to the blood levels of CNI: Of all these subjects, Th17 and Treg frequencies in the peripheral blood were analyzed by flow cytometry (FCM). Serums IL-17, IL-23, IL-6, IFN-r, and TGF-β were analyzed by ELISA. The results demonstrated that the transplantation recipient treated by CNI revealed an obvious increase in peripheral Th17 frequencies and a significant decrease in Treg frequencies when compared with the sirolimus group and healthy people (P < 0.05). Even more, the transplantation recipient with renal dysfunction had the highest level of Th17 cells (P < 0.05) while the lowest Treg cells compared with stable recipient and healthy control, with increased serums IL-6 and IL-17. Our results indicated that CNI was associated with Th17/Treg imbalance in peripheral blood, which supported the followed generation of renal dysfunction after transplantation.     

结核患者外周血中辅助性T细胞17及白细胞介素-17水平的变化

目的:探讨结核患者外周血辅助性T细胞17(Th17细胞)及白细胞介素-17(IL-17)水平变化及意义。方法:以结核患者98例(初治58例,复治40例)、健康对照者98例为研究对象,抽取研究对象外周血并分离外周血单核细胞(PBMC)和血浆,采用流式细胞术(FCM)检测PBMC中Th17细胞的百分率,酶联免疫吸试验(ELISA)检测血浆中IL-17水平;用灭活的结核分枝杆菌菌株(H37Rv)分别刺激结核患者和健康对照者PBMC,ELISA法检测其上清中IL-17水平。结果:与健康对照者比较,结核患者外周血Th17细胞比例[(5.2±1.8)%vs(1.8±1.4)%,P<0.05]及IL-17水平[(68.22±10.31)vs(39.81±14.58)pg/ml,P<0.01]显著增高;与初治组比较,复治组Th17细胞比例[(6.4±1.8)%vs(3.8±1.3)%,P<0.05]及IL-17水平[(85.46±9.13)vs(51.22±12.36)pg/ml,P<0.05]显著增高;结核患者血浆IL-17水平与Th17细胞的比例呈正相关(r=0.912,P<0.05);H37RV刺激结核病人和健康对照者PBMC后上清中均有IL-17的表达,且结核病人来源的表达水平更高。结论:结核患者外周血Th17细胞比例及IL-17水平增高,Th17细胞和IL-17在结核病的发生发展中发挥了重要作用。     

Immunosuppression based on mycophenolate mofetil in stable liver transplanted patients

AIM: To analyze our results with mycophenolate mofetil (MMF) in stable liver transplantation (LT) patients presenting with adverse events (AE) related to prolonged use of calcineurin inhibitors (CNI). METHODS: Conversion to MMF was performed in 56 out of 323 LT patients from 91-02: 24 (43%) were converted to MMF in monotherapy and 32 (57%) to MMF+low doses of CNI. The indication for conversion was chronic renal insufficiency (CRI) in all patients. The mean time between AE and conversion was 38.7+/-30 months (r: 2-101 m). Post-conversion follow-up was 39+/-20 months (r: 3-72 m). RESULTS: The calculated creatinine clearance (Crauckoft), improved significantly in all patients. In those converted to MMF, improvement was seen during the first 18 months for urea and during the first 6 months for creatinine. In patients converted to MMF+CNI, improvement was maintained throughout the conversion period for both urea and creatinine. Eleven (19.6%) patients underwent acute rejection (2 severe episodes in the MMF group and 1 death). Hypertension was present in 31 patients but only improved in 4 (7%). Dyslipemia was found in 12 and improved in 4 (7%). DM was present in 14 and improved in 1 (2%). CONCLUSIONS: Conversion to MMF in monotherapy is useful in stable LT patients with CRI due to CNI, although this result is offset by more severe rejections. Therefore, for AE secondary to CNI, we propose an early conversion to MMF+low doses of CNI as a first step. If liver function remains stable and AEs persist or progress, conversion to MMF in monotherapy is recommended, as a second step, with close monitoring of the patient.     

Clinical trial: switch to combined mycophenolate mofetil and minimal dose calcineurin inhibitor in stable liver transplant patients--assessment of renal and allograft function, cardiovascular risk factors and immune monitoring

BACKGROUND: Calcineurin inhibitor (CNI)-related nephrotoxicity significantly contributes to chronic renal failure after liver transplantation. METHODS: In this prospective study, liver transplantation patients with renal dysfunction were randomized either to receive mycophenolate mofetil (MMF) followed by stepwise reduction of CNI with defined minimal CNI-trough levels (MMF group), or to continue their maintenance CNI dose (control group). Immune monitoring was performed in a subgroup of the patients. RESULTS: In the MMF group (n = 50), renal function assessed by serum creatinine improved >10% in 62% of patients, was stable in 36% and deteriorated >10% in 2% after 12 months compared with baseline values. Mean serum creatinine levels (+/- s.d.) significantly decreased from 1.90 +/- 0.44 mg/dL to 1.61 +/- 0.39 mg/dL and the corresponding calculated glomerular filtration rate significantly increased from 38.8 +/- 9.6 mL/min/1.73 m(2) to 47.0 +/- 11.8 mL/min/1.73 m(2) over a 12-month follow-up period. Blood pressure and levels of liver enzymes significantly decreased. In the control group (n = 25), there were no significant changes with respect to the investigated parameters. The MMF group had significantly lower numbers of circulating cytotoxic T cells compared with the controls; whereas regulatory T cells significantly increased. CONCLUSION: Combined MMF and minimal dose CNI therapy after liver transplantation is nephroprotective and may promote allograft tolerance.     

低剂量环磷酰胺辅助治疗复发性尖锐湿疣的疗效及其对辅助型T17细胞的影响

目的 观察低剂量环磷酰胺辅助治疗复发性尖锐湿疣的疗效及其对辅助型T17细胞的影响。方法 80例患者随机分为对照组和观察组,各40例,对照组予CO₂激光联合5-氨基酮戊酸光动力疗法治疗,每周1次,连续4周;观察组加用环磷酰胺50 mg口服,连用7 d,停药3 d,再连用7 d。比较患者复发情况、HPV基因型分布;流式细胞仪检测外周血中Th17细胞比例,ELISA法检测IL-17和IL-23蛋白含量,RT-PCR检测IL-17和IL-23 mRNA表达情况;记录不良反应。结果 观察组治疗后3,6,9,12个月时的复发率分别为5.0%,10.0%,15.0%和17.5%,均低于对照组的20.0%,32.5%,40.0%和47.5%（P<0.05）;Th17细胞比例、IL-17、IL-23蛋白及mRNA含量均较对照组明显降低;80例患者共检出9种HPV基因型,观察组HPV清除率（90.0%）显著高于对照组（70.0%,P<0.05）;2组不良反应发生率相近。结论 低剂量环磷酰胺联合5-氨基酮戊酸光动力、CO₂激光,对复发性尖锐湿疣具有良好治疗作用,且安全性良好。     

Affects of immunosuppression on circulating dendritic cells: an adjunct to therapeutic drug monitoring after heart transplantation

OBJECTIVES: Recent evidence emerges dendritic cells (DCs) as pharmacological targets of immunosuppressive drugs. Therefore, in this study we monitored DCs in peripheral blood to compare the effects of calcineurin inhibitors (CNI: cyclosporine, tacrolimus) and mammalian target of rapamycin inhibitors (sirolimus, SRL, everolimus, ERL) basis-immunosuppressive therapies in human heart transplanted (HTx) recipients. METHODS: We compared HTx recipients which were converted from either CNI to ERL (severe renal dysfunction, n=8), or from SRL to ERL (approval of ERL for HTx, n=8) with 20 healthy human controls. Twenty four after the last CNI or SRL dose recipients were treated with ERL/BID on days 1-3. Peripheral blood was collected at trough in the morning before and on day 4 after conversion. Percentages of positive myeloid and plasmacytoid DC (m and pDC) subsets in peripheral blood were analysed by flow cytometry. The status of maturation was further characterised by flow cytometry analysis of % expression of CD83 and % expression of various intracellular cytokines (IL-1beta, TNF-alpha, IL-8, IL-12), respectively. RESULTS: HTx recipients had higher % positive mDCs regardless the immunosuppressive therapy compared to controls (p<0.05). Whereas, % positive pDCs were only significantly lower in recipients converted from CNI to ERL compared to controls (p<0.05). The data consolidate the finding that the subset ratio pDCs/mDCs was lower in recipients compared to controls. But after conversion from CNI or SRL to ERL the ratio increased towards pDCs. Percentages of expression of CD83 on mDCs were not different among the recipient groups and controls. Recipients with CNI and SRL had higher % expression of IL-12 and lower % expression of IL-1beta compared to controls (p<0.05). However, after conversion to ERL % expression of both IL-12 and IL-1beta returned to control values in both groups. CONCLUSIONS: The results showed that analysis of immunosuppression of circulating DCs in peripheral blood may be an adjunct to therapeutic drug monitoring to optimize immunosuppressive therapy after HTx.     

Effects of calcineurin inhibitors on pharmacokinetics of mycophenolic acid and its glucuronide metabolite during the maintenance period following renal transplantation

Mycophenolic acid (MPA), the active metabolite of mycophenolate mofetil (MMF) has been introduced into renal transplant immunosuppressant protocols in combination with calcineurin inhibitors (CNIs) and steroids. This study compared the pharmacokinetic profiles of MPA and its major metabolite MPA glucuronide (MPAG) in combination with tacrolimus (TAC) or cyclosporine (CyA) during the maintenance period (>6 months) following renal transplantation. There was no difference between TAC and CyA-treated groups in MPA plasma concentration before drug administration (C(0)). MPA C(0) in TAC and CyA-treated patients did not differ from that in patients who were not treated with a CNI. In patients treated with a CNI, MPAG C(0) was significantly greater in those treated with CyA compared with TAC. The MPAG/MPA ratio in CyA-treated patients was significantly greater than that in the TAC-treated group. We observed that C(0) of MPA was negatively correlated with that of TAC and CyA. Positive correlation between MPA C(0), MPAG C(0) and serum creatinine was stronger in patients treated with CyA compared with TAC. Our study suggests that CyA, but not TAC, inhibits enterohepatic circulation of MPAG as a secondary excretion pathway, and that renal function makes a major contribution to elimination of MPA and MPAG. We indicate that it may be necessary to estimate biliary excretion of MPAG to avoid the risk of intestinal injury in patients receiving combination therapy with TAC during the maintenance period.     

Nonnephrotoxic immunosuppression in patients after liver transplantation

INTRODUCTION: Calcineurin inhibitor (CI)-associated renal impairment and renal failure after liver transplantation has been recognized since the early days of its use. Various strategies have been used to prevent or slow down the progression of renal dysfunction in liver transplant recipients, but did not succeed. In this report, we describe the course of renal function of 58 stable liver transplant recipients and compared 2 groups with different immunosuppressive protocols. METHODS: In the study group, 22 patients at various intervals from liver transplantation were included. The immunosuppressive therapy consisted of Sirolimus (SRL). Additional all patients except 2 received Mycophenolate Mofetil (MMF) and 14 of them also received Tacrolimus. Patients of the control group (36 patients) had an immunosuppressive therapy with calcineurin inhibitors. Patients were monitored for creatinine monthly and creatinine clearance (CCr) every sixth month. Risk factors for renal dysfunction were evaluated. RESULTS: After introduction of SRL in patients with renal impairment and after a mean follow-up time of 12 (2-26) months, there was a decrease of 28.3% in mean creatinine and of 41.8% in mean urea. We observed an improvement of renal function in all patients initially after introduction of SRL. In the control group, in comparison to preoperative levels, there was an increase of 27.5% in mean creatinine and of 13.3% in mean urea after a mean follow-up time of 3.6 years with CI therapy. CONCLUSION: The results of our retrospective study showed that with SRL renal impairment could be stopped and renal function could be improved. We suggest administering immunosuppressive therapy with SRL in combination with low dose Tacrolimus and/or MMF for patients with renal impairment.     

A clinical pharmacokinetic study of tacrolimus and sirolimus combination immunosuppression comparing simultaneous to separated administration

The pharmacokinetic (PK) interaction between tacrolimus (TAC) and sirolimus (SRL), similarly structured immunosuppressive compounds that share binding proteins, is unknown. The combination of SRL with cyclosporin (CsA) has been studied, and a 4-hour interval between dosing of the two drugs is recommended even though it is inconvenient for patients and may affect compliance. Twenty-five liver and kidney-pancreas transplant recipients treated with a combination of SRL and low-dose TAC completed full PK studies while being treated with 4-hour interval dosing (ID) and then with simultaneous dosing. Whole blood was sampled for immunoassay measurement of TAC and SRL levels. Blood concentration/dose ratios of SRL and TAC varied between patients by a factor of 8 and 5, respectively, but correlation between trough concentration levels (C(0)) and drug exposure area under the concentration-time curve (AUC) was excellent (TAC: r(2) = 0.82; SRL: r(2) = 0.83). Neither PK profiles of SRL nor those of TAC were altered by simultaneous administration. Dose-corrected AUC and C0 of TAC correlated with SRL (r(2) = 0.8 and 0.8, respectively). Bone marrow suppression and nephrotoxicity were not enhanced nor were any new toxicities observed when TAC and SRL were used in combination. These data confirm that simultaneous dosing of TAC and SRL after transplantation is safe and that trough level monitoring is adequate to control therapy.     

Emodin attenuates acute rejection of liver allografts by inhibiting hepatocellular apoptosis and modulating the Th1/Th2 balance in rats

1. In the present study, we investigated the immunosuppressive effects and mechanisms of action of emodin on acute graft rejection following liver transplantation in a rat model of orthotopic liver transplantation. 2. Rats were divided into three groups: Group A, syngenic control (Brown Norway‐to‐Brown Norway); Group B, acute rejection group (Lewis‐to‐Brown Norway); and Group C, emodin‐treated group (Lewis‐to‐Brown Norway treated with 50 mg/kg emodin, 50 mg/kg.d, injected intraperitoneally once a day from days 1 to 5 posttransplantation). The survival time of the recipients in each group was recorded. Histopathological changes in the liver, hepatocellular apoptosis, serum concentrations of interleukin (IL)‐2, interferon (IFN)‐γ and IL‐4 and their expression in liver tissue were determined. 3. Emodin treatment prolonged liver allograft survival time from 10.9 days in Group B to 25.6 days in Group C. The rejection activity index (calculated according to the Banff Schema) in Groups A, B and C was 1.29 ± 0.47, 7.58 ± 0.85 and 4.72 ± 0.79, respectively (P < 0.01 for Groups A and B vs Group C), whereas the apoptosis index in the three groups was 15.51 ± 1.47, 39.50 ± 1.65 and 16.72 ± 1.73, respectively (P < 0.01 for Groups A and C vs Group B). Serum levels of IL‐2 and IFN‐γ were higher, whereas levels of IL‐4 were lower, in the acute rejection group (Group B) than in the emodin‐treated group (Group C; P < 0.05). Changes in the expression of these cytokines in transplanted liver tissue were consistent with changes in serum concentrations. 4. In conclusion, emodin effectively suppresses acute graft rejection in vivo to prolong the survival of recipient rats. The mechanism underlying this effect may be associated with the prevention of hepatocyte apoptosis and with a changing in the balance of Th1/Th2 cytokines towards Th2.     

麦考酚酸酯在肾移植中的应用

目的：观察麦考酚酸酯（ ｍｙｍcoｐｈｅｎｏｌａｔｅｍｏｆｅｔｉｌ,ＭＭＦ）预防移植肾急性排斥的安全性及有效性。方法：４０例肾移植病人分为２组,２０例［男性１２例,女性 ８例,年龄（４３ ± ｓ １０） ａ］为治疗组,给予ＭＭＦ1ｇ, ｐｏ, ｂｉｄ;另 ２０例［男性 １３例,女性 ７例,年龄（４５±１１） ａ］为对照组,给予硫唑嘌呤（Ａｚａ） １５０ｍｐ,ｐｏ, ｑｎ。共 ６ ｍｏ。结果： ＭＭＦ组急性排斥反应发生率为０,Ａｚａ组为２例,２组间差异无显著意义（Ｐ＞０．０５）。２组病人的消化道反应、肝中毒、感染等并发症的发生率的差异无显著意义（Ｐ＞０．０５）。结论：ＭＭＦ是一种能预防移植肾急性排斥反应的安全、有效的免疫抑制剂。     

卡介菌多糖核酸对生殖器疱疹病人血CD4~+T细胞细胞因子表达影响

目的:研究卡介菌多糖核酸(BCG-PSN)对复发性生殖器疱疹(RGH)病人外周血CD4+T细胞内白细胞介素12(CD4+T-IL-12),干扰素γ(IFN-γ),白细胞介素4(IL-4)表达的影响。方法:用流式细胞仪检测30例经BCG-PSN治疗、15例未予BCG-PSN治疗的RGH病人与15名正常人外周血CD4+T-IL-12,IFN-γ和IL-4表达。结果:治疗前RGH病人外周血CD4+T-IL-12,IFN-γ表达较正常组下降[(1.8±s0.5)%vs(3.3±1.9)%,(3.5±2.6)%vs(5.3±1.5)%;P<0.01],IL-4表达上升[(3.0±0.5)%vs(2.2±0.8)%,P<0.01]。治疗后BCG-PSN组外周血CD4+T-IL-12和IFN-γ水平升高[(3.1±1.6)%vs(1.8±0.5)%,P<0.01;(5.0±2.6)%vs(3.6±2.6)%,P<0.05],IL-4表达下降[(2.4±0.5)%vs(3.0±0.5)%,P<0.01],Th1/Th2恢复正常。结论:RGH病人存在Th1/Th2失衡和IL-12表达低下;BCG-PSN通过诱导外周血CD4+T-IFN-γ,IL-12表达,下调IL-4表达,纠正病人免疫紊乱而提高临床疗效和预防复发。     

支气管哮喘患者外周血Th1、Th2与Th17细胞表达水平及临床意义

目的 探讨外周血Th1、Th2与Th17细胞在支气管哮喘患者中的表达水平及临床意义.方法 选取2015年1月-2016年2月诊治的支气管哮喘40例,均为急性发作期,治疗1周后为缓解期,选取同期健康人40例作为对照组.检测支气管哮喘急性发作期、缓解期和对照组外周血Th1、Th2与Th17细胞水平,观察外周血中干扰素(IFN)-白介素(IL)-4及IL-17的表达情况.结果 支气管哮喘组急性发作期和缓解期Th1、Th1/Th2、IFN-γ的表达水平低于对照组,且急性发作期低于缓解期(P＜0.05);支气管哮喘组急性发作期和缓解期Th2、Th17、IL-4、IL-17表达水平高于对照组,且急性发作期高于缓解期(P＜0.05).结论 支气管哮喘患者外周血Th1、Th2与Th17细胞表达水平失衡,导致IFN-γ、IL-4及IL-17异常分泌,可能参与支气管哮喘的发病.     

Mycophenolic acid plasma concentrations: influence of comedication

Mycophenolate mofetil (MMF) in combination with cyclosporine (CsA) or Tacrolimus (TAC) has been show to be a potent immunosuppressive agent. The authors assessed the mycophenolic acid (MPA) plasma levels achieved in clinical practice and evaluated the effect of concomitant administration of CsA and TAC . One hundred forty transplant patients (kidney: 120 and lung: 20) received a triple immunosuppression regimen of CsA or TAC, prednisone and MMF. Twenty-two renal transplant patients received double therapy with MMF and prednisone. There was no correlation between MMF dose and MPA trough concentrations (r = -0.0657). The medians (range) of the MPA dose-to-concentration ratio (D/C) in the CsA and TAC groups were 0.90 (0.11-8.33) and 0.56 (0.11-14.3), respectively (p < 0.0001). According to the post transplant period (1-3, 4-6 and >6 months), D/C values were significantly lower in patients receiving MMF and TAC than those receiving MMF and CsA in all three periods. MPA levels in patients treated with MMF and CsA were significantly lower than those obtained in double therapy. The D/C ratio in CsA-treated patients, increased significantly (p = 0.0005) when CsA level increased. There was no relationship between D/C ratio and TAC blood concentrations. These results suggest that CsA exerts an influence on MPA trough levels, although further work is required to characterize the mechanism of interaction.     

The evaluate and compare the effects of the Tacrolimus and Sirolimus on the intestinal system using an intestinal cell culture model

Tacrolimus (TAC) and Sirolimus (SRL) are produced by Streptomyces sp and effective immunosuppressive drugs commonly used in organ transplantation. Therefore, strategies for minimizing the toxicity of immunosuppressant molecules are our interest. This study was conducted to evaluate the interactive effects and the possible underlying mechanism of TAC and SRL on HCT116 cells. It was found that TAC and SRL alone inhibited cell viability. Also, it induced reactive oxygen species (ROS) formation, loss of mitochondrial membrane potential (Δψm), and able to increase DNA fragmentation in a concentration-dependent manner. The use of combined SRL and TAC showed a reservation in all toxicity observed with the two immunosuppressive drugs separately. Our result demonstrated that the mechanisms of TAC and SRL at high concentration are closely connected with oxidative stress. Furthermore, SRL at low concentration plays a protective effect against TAC (IC₅₀) which induced cytotoxicity and genotoxicity. However, using the combination of the SRL/TAC at high concentrations (IC₃₀) appears as an antagonist response.     

Effect of hepatic drug transporter polymorphisms on the pharmacokinetics of mycophenolic acid in patients with severe renal dysfunction before renal transplantation

1.?The objective of this study was to examine the association of UGT1A9, SLCO, and ABCC polymorphisms with mycophenolic acid (MPA) pharmacokinetics in ABO blood type (ABO) incompatible patients with severe renal dysfunction pre-transplantation.

2.?In all patients, on day 14 after beginning mycophenolate mofetil (MMF) treatment (1 week before transplantation) and on day 28 after renal transplantation, samples were collected just prior to and 1, 2, 3, 4, 6, 9, and 12?h after oral MMF administration.

3.?The median dose-adjusted AUC_0–12 of MPA after renal transplantation was significantly lower than before transplantation (57.9 versus 76.5?μg h/mL, respectively, p?=?0.002).

4.?Although the enterohepatic circulation of MPA pre-transplantation was extremely high (57.6%), this level was significantly reduced after renal transplantation (34.6%).

5.?In the multivariate analysis, pre-transplantation, patients with the SLCO1B3 334T allele (p?=?0.003), higher alanine aminotransferase (p?=?0.002), and lower body weight were independently predictive for a higher dose-adjusted AUC_0–12 of MPA.

6.?In patients with severe renal dysfunction pre-transplantation, MPA is excreted mainly to bile from the liver, and as a consequence, the SLCO1B3 334T?>?G polymorphism was found to be significantly associated with MPA exposure.     

实验性自身免疫性脑脊髓炎大鼠Th1、Th2和Th17免疫反应检测

目的探讨不同类型免疫反应在实验性自身免疫性脑脊髓炎(EAE)发病中的作用。方法 24只SD大鼠随机均分为EAE组和对照组,通过行为观测和大脑微观形态学确认免疫诱导的EAE模型,用ELISA法检测淋巴结和脾细胞培养上清液中IL-4、IFN-γ和血清中IgG水平,流式细胞术检测淋巴结和脾细胞中IL-17及Foxp3细胞频数。结果与对照组相比,EAE组IgG、IFN-γ、IL-17及IL-4水平均明显增高(P<0.05或P<0.01)。结论 Th1、Th2和Th17免疫细胞在EAE的发病均起着重要的作用。     

白介素-18对肝癌裸鼠皮下移植瘤浸润的CD4+T细胞子集的影响

目的探讨白介素-18(IL-18)影响肝癌裸鼠皮下移植瘤浸润的T细胞子集变化的机制。方法以HepG2细胞在裸鼠皮下接种,形成人肝癌皮下移植瘤的同时,以不同剂量IL-18分为4组治疗,4组分别腹腔注射IL-18 0.75,1.00,1.25,0(模型组)μg(0.1 mL)/只,治疗4周,另设正常对照组。观察肿瘤的生长速度和瘤体大小的变化。4周后处死取肿瘤组织和脾组织,免疫磁珠阴选组织中CD4+T细胞,流式细胞术检测各组肿瘤组织及脾组织中IL-17+/IFN-γ-CD4+T(Th17细胞)、IL-17-/IFN-γ+CD4+T(Th1)和IL-17+/IFN-γ+CD4+T细胞的变化。结果 HepG2细胞株建立了裸鼠肝癌皮下移植瘤模型,IL-18抑制人肝癌皮下移植瘤的形成及转移,治疗时间越长剂量越大,抑制效果越明显;与正常对照组比较,肿瘤组织中Th17和IL-17+/IFN-γ+CD4+T细胞浸润数目增加,Th1细胞降低,与脾组织中一致,与正常对照组比较有显著差异(P<0.05)。给IL-18后,随着剂量的增加,Th1细胞增加,IL-17+/IFN-γ+CD4+T细胞和Th17细胞浸润数目降低,给药组与模型组比较有显著差异(P<0.05或0.01)。结论 IL-17+/IFN-γ+CD4+T细胞数目在裸鼠移植瘤及其脾组织中增加,可能是在肿瘤环境中,促进其向Th17细胞分化;IL-18通过诱导IFN-γ的生成促进Th1细胞的生成,呈正反馈效应抑制肿瘤的增殖和转移。     

MicroRNA-21 silencing prolongs islet allograft survival by inhibiting Th17 cells

It has been reported that microRNA-21 (miR-21) augments Th17 responses and contributes to the pathogenesis of autoimmune diseases. Gene knockout or siRNA-induced knockdown of miR-21 in mice resulted in impaired Th17 differentiation and strong resistance to experimental autoimmune encephalomyelitis (EAE). Recently, we validated the miR-21 target IL-10 mRNA and showed that it exerts a pro-inflammatory role by inhibiting IL-10-expressing regulatory B cell (B10) differentiation. The administration of miR-21 antisense oligonucleotides (antagomiR-21) in vivo potently suppressed the severity of EAE, and the suppressive activity was mediated by an increased number of B10 cells. However, the contribution of the miR-21 pathways involved in transplant rejection remains obscure. In this study, we examined the impact of systemic administration of miR-21 inhibitor on allografts in a pancreatic islet transplantation model. We showed that specific miR-21 silencing in vivo significantly prolonged allograft survival (median survival time (MST) 21 days with antagomiR-21 vs 13 days for the control, p < 0.05), and the change was associated with a decrease in Th17 cells (~3-fold) and an increase in B10 cells (~2.4-fold). Moreover, we found that miR-21-silenced B cells mediate this protective role through pro-inflammatory Th17 responses in an IL-10-dependent fashion. Thus, we have revealed a novel mechanistic pathway that modulates Th17 development and alloimmunity. Targeting miR-21 may represent a valuable therapeutic intervention strategy for preventing transplant rejection.