Prolongation of heart allograft survival of rats treated by a Th2 inhibitor

In terms of Th1/Th2 balance in response to signals given during donor antigen presentation, induction of tolerance is more often correlated with Th2-type than with Th1-type reactions. However, in our study, heart allograft survival was prolonged by treatment of rats with a Th2 inhibitor. Suplatast tosilate (IPD; Taiho; Tokyo, Japan) is a novel immunoregulator that suppresses IgE production and eosinophil infiltration through selective inhibition of interleukin (IL)-4 and IL-5 synthesis by Th2-like cells but not IFN-gamma production in Th1 cells. Five LEW rats of DA heart grafts were treated with IPD (100 microg/day, p.o.) for 10 days. Heart allograft survival of all IPD-treated cases was prolonged more than 14 days while the beating of heart grafts in control groups was stopped within 9 days. In an in vitro study, the cell proliferation both in Con A blast and in mixed lymphocyte reaction assay was suppressed by IPD in dose-dependent manner. We could at least in part conclude that Th2 inhibition might temporarily suppress heart allograft rejection.     

Subclinical impairment of distal renal acidification induced by low-dose cyclosporin A therapy

Twenty-nine psoriasis patients on 5 mg/kg cyclosporin A (CyA) therapy were studied for 3 months using the furosemide test. Five of them (17 %) showed an abnormal renal acidification capacity after furosemide administration: The urinary pH did not sink under 5.3 after furosemide, while the ammonium and titrable acid levels were significantly low. There were no significant differences from controls regarding the serum potassium or fractional potassium excretion. Nevertheless, the transtubular potassium gradient was lower in patients with an abnormal furosemide test result. We conclude that some patients treated with a low dose CyA therapy developed an abnormality in the distal tubular acidification.     

Effect of LS-2616 on the graft protection achieved by cyclosporin A,prednisolone, and 15-deoxyspergualin in heart-transplanted rats

The immunostimulator LS-2616 abolishes the effect of cyclosporin A in a rat cardiac transplantation model. The present paper compares the characteristics of rejection obtained under different immunosuppressive regimens with and without additional LS-2616 application in the same model. Cyclosporin A (CyA, 10 mg/kg daily), prednisolone (15 mg/kg daily), or 15-deoxyspergualin (2, 5, or 10 mg/kg daily), all given from the day of transplantation until day 9, protected the grafts during the treatment period. The addition of LS-2616 (160 mg/kg, day —1 until stop) resulted in a total abrogation of the immunosuppressive effect of CyA and prednisolone. However, LS-2616 could only partially or not at all reverse the effect of 15-deoxyspergualine. These results show a certain drug selectivity of LS-2616 in promoting rejection of immunosuppressed allografts. Further studies with LS-2616 may be of benefit in evaluating the mode of action of different immunosuppressive compounds and, thus, contribute to finding more effective antirejection therapies.     

小剂量环孢素A对大鼠同种异体肢体移植的免疫抑制作用

目的通过大鼠同种异体肢体移植模型,分析小剂量环孢素A(cyvlosporinA ,CsA)对大鼠同种异体肢体移植急性排斥反应的免疫抑制作用。方法采用雄性Wistar和SD大鼠为供、受体,以CsA为免疫抑制剂。对照组14只,将Wistar大鼠肢体移植至SD大鼠,术后不用药。实验组术后按用药剂量的不同分为2组( 2mg/kg组17只大鼠和CsA 6mg/kg组18只大鼠)。2组术后用药时间均为4周(每日1次共2周,然后每周2次共2周)。术后观察大鼠一般情况、移植肢体排斥反应及存活时间;用免疫荧光染色流式细胞仪检测各组手术前后T细胞亚群的变化。结果对照组移植肢体平均存活时间为[( 7.0 0±0 .78)d , x±s ,下同] ;CsA 2mg/kg组为( 3 7.18±0 .5 1)d ,CsA 6mg/kg组为( 3 3 .2 0±1.0 5 )d。术后第3天,对照组的CD4/CD8比值显著增高,移植肢体开始出现肿胀、皮肤红斑等表现。实验组的CD4/CD8较术前无明显变化。结论小剂量CsA能抑制大鼠同种异体肢体移植术后急性排斥反应的发生,并能延长移植肢体的存活时间。     

Tacrolimus versus cyclosporin A: a comparative study on rat renal allograft survival

Although tacrolimus has been studied in a wide variety of experimental animal models, we are the first group to systematically study the effect of tacrolimus on rat renal allograft survival, as primary therapy and as anti-rejection therapy, in comparison with cyclosporin A (CyA). Renal grafts were transplanted from BN to LEW rats. Tacrolimus and CyA were administrated orally from day 0 for 50 days as primary therapy after grafting. Allografts were rejected after a median survival time (MST) of 8 days. Both tacrolimus und CyA significantly prolonged renal allograft survival, in a dose-dependent manner compared with the allograft controls. The most effective dose was 3.2 mg/kg, per day for tacrolimus, and 10 mg/kg per day for CyA. There was no significant difference in renal function between the group treated with the most effective dose of tacrolimus and the CyA-treated group. The percentage of detectable serum IL-2 level was 45 % in the allograft control group, but was undetectable in groups treated with the most effective dose of tacrolimus or CyA at days 3 and 6 after grafting. On the other hand, no side effects were noted in recipient rats by daily inspection, body weight change, and histological studies, although minimal tubular vacuolation was encountered in the group treated with CyA 32 mg/kg per day. In addition, the most effective doses of tacrolimus and CyA were studied as anti-rejection therapy. All of the 5 recipients treated with tacrolimus from days 2–14, and 3 of the 5 treated from days 4–16 after grafting, survived for more than 50 days. However, the MST was 19 days for recipients treated with CyA from days 2–14, and 13 days for those treated from days 4–16 after grafting. In summary, tacrolimus as primary therapy induced rat renal allograft survival with renal function and side effects comparable with those of CyA. Interestingly, when both agents were used as anti-rejection therapy, tacrolimus, but not CyA, could significantly overcome ongoing renal allograft rejection in the rat. Received: 31 March 1998 Received after revision: 9 September 1998 Accepted: 12 October 1998     

A case of prolonged allograft survival after a short-term treatment with cyclosporin A in a child with aplastic anemia

Summary A child with severe idiopathic aplastic anemia was treated with cyclosporin A for 16 weeks. Skin necrosis occurred on the dorsum of the left hand; mucormycosis was cultured. An underlying osteomyelitis was suspected. The defect was covered with live donor allograft skin, since it was feared that there would be considerable bleeding from autograft donor sites. There was no evidence of graft rejection, either during treatment or in the year after cyclosporin A was withdrawn. No evidence of mucormycosis or osteomyelitis was seen subsequent to skin grafting.     

弓形虫感染对大鼠移植心脏存活时间的影响

目的探讨受者弓形虫感染对同种心脏移植物存活时间的影响。方法通过腹腔注射的方法建立弓形虫感染的大鼠模型,分别于感染后4~7d(急性感染组)或感染后27~32d(慢性感染组)进行同种异体颈部心脏移植,并设注射生理盐水的对照组和同系移植对照组。术后不用免疫抑制剂,观察移植心脏的存活时间以及移植物的病理变化。结果同系对照组的移植物存活时间为(135.3±30.4)d;慢性感染组移植心脏的存活时间为(73.6±49.3)d,明显长于生理盐水对照组和急性感染组(P<0.01),其移植心脏组织中的炎症细胞浸润也较对照组显著减轻,尤其是移植物存活时间超过100d者,无慢性移植物病变。结论受者的弓形虫感染能显著延长同种心脏移植物的存活时间,减轻移植物炎症反应。     

含丝裂霉素C的灌注液对大鼠移植心脏存活时间的影响

目的研究含丝裂霉素C灌注液对心脏移植物存活的影响以及作用机理。方法BN大鼠做供体,Lewis大鼠做受体。用含丝裂霉素c的溶液灌注及保存Brown—Norway大鼠供体心脏．移植到Lewis大鼠受体。为分析丝裂霉素C的体内效应,受体于术后注射丝裂霉素C或用丝裂霉素C孵化的供体外周血单核细胞进行预处理。结果含丝裂霉素C的灌注液能够显著延长移植物存活．丝裂霉素C预处理受体不能延长移植物存活,但注射丝裂霉素C预处理供体的外周血单核细胞致受体能够延长移植物存活。结论对供体心脏用含丝裂霉素C溶液灌注可减轻移植物的排斥反应,显著延长移植心脏的存活时间。     

Prolongation of allograft and xenograft survival in mice by anti-CD2 monoclonal antibodies.

Anti-CD2 monoclonal antibodies (mAb) were used to influence graft survival in two transplantation models. Xenogeneic rat islets were transplanted intraportally into mice. Anti-CD2 mAb prolonged xenograft survival and was synergistic with UVB irradiation in prolonging survival. Anti-CD2 mAb was also more potent than an anti-CD4 mAb in this model. Allogeneic cardiac grafts were transplanted across an entire H-2 difference and anti-CD2 mAb prolonged allograft survival in a dose-dependent fashion. Kinetic experiments revealed that anti-CD2 mAb was most potent when administered at the time of allografting. A delay in administration of mAb markedly reduced its immunosuppressive effects. Furthermore, additional doses of mAb given after the initial doses provided no increased immunosuppression and anti-CD2 mAbs did not delay rejection of second-set allografts. These findings support the notion that anti-CD2 mAbs interfere with afferent immunity and that CD2 is most important during the initial steps of an immune response. Investigation of the effect of anti-CD2 mAb on cellular immune functions demonstrated, in agreement with previous results, that it caused antigenic down-modulation of CD2 with relative sparing of CD3, CD4, and CD8 cell surface expression. Concomitantly the MLR, CTL, and NK responses were suppressed.     

环孢素A与盐酸小檗碱联用预防大鼠心脏移植排斥反应

目的探讨环孢素A(CsA)与盐酸小檗碱联用对同种异基因大鼠心脏移植排斥反应的抑制效果。方法建立Wistar大鼠心脏到SD大鼠的异位(腹腔内)心脏移植模型,术后单独使用CsA、盐酸小檗碱以及联合使用CsA和盐酸小檗碱进行免疫抑制治疗,观察各组移植心脏的存活时间。结果单独使用不同剂量CsA者移植心脏的存活时间较安慰剂组明显延长(P<0.01);CsA和盐酸小檗碱联用组移植心脏的存活时间较单用小剂量CsA组明显延长(P<0.01);单用盐酸小檗碱组与安慰剂组相比,移植心脏存活时间的差异无统计学意义(P>0.05)。结论CsA与盐酸小檗碱联用预防大鼠心脏移植后的排斥反应具有协同作用。     

A short-term combination therapy with cyclosporine and rapamycin or leflunomide induces long-term heart allograft survival in a strongly immunogenic strain combination in rats

Abstract  Synergism between cyclosporine (CsA) and rapamycin (RAPA) or leflunomide (LF) was studied in a strongly immunogenic cardiac allograft model in rats. In the absence of immunosuppression, PVG recipients rejected WKAH heart grafts after a mean survival time (MST) of 5.2 ± 1.1 days. A dose of 7.5 mg/kg per day CsA did not prolong graft survival (MST 5.6 ± 1.2 days). CsA given at 10 mg/ kg per day for 30 days extended MST of the grafts to 48 ± 7 days. A short course of combination therapy consisting of adding a non-therapeutic dose of RAPA or a subthera-peutic dose of LF to a 1-month course of CsA resulted in permanent graft survival. These data suggest that RAPA and LF synergize with CsA enabling not only the lowering of the dose of CsA, but also inducing transplantation tolerance.     

Enhancement of the immunosuppressive effect of cyclosporin A by ciprofloxacin in a rat cardiac allograft transplantation model

Ciprofloxacin hyperinduces interleukin-2 production in stimulated human and mouse lymphocytes. In this study, an enhanced and prolonged interleukin-2 response was also detected in polyclonally stimulated rat splenocytes in the presence of ciprofloxacin (5–80g/ml) compared to control cells without any antibiotic. Ciprofloxacin was able to counteract the immunosuppressive effect of 10ng/ml cyclosporin A (CyA) but did not interfere with higher CyA concentrations. In parallel, ciprofloxacin did not influence thymidine uptake in mixed lymphocyte reactions in the presence of CyA. To obtain an in vivo application of these findings, graft survival was studied by performing rat cardiac allograft transplantations in the presence or absence of CyA. Brown Norway rats served as donors and Wistar Furth rats as recipients. Ciprofloxacin was injected intraperitoneally either at a high-dose regimen (240 mg/kg per 24h) into rats every 8th h starting 1 day before transplantation until day 21 or graft loss, or it was injected at a low and clinically relevant dose regimen (45mg/kg per 24h) until day 9. CyA was administered orally (10mg/kg per 24h) from day 1 through day 9. Ciprofloxacin given alone at a high-dose regimen resulted in a median graft survival of 14.8 days, which was significantly longer than graft survival in rats without treatment (median 8.0 days). A low-dose regimen of ciprofloxacin alone did not affect graft survival. Ciprofloxacin at a highdose regimen combined with CyA prolonged graft survival to a median of 24.0 days compared to 20.5 days with CyA alone. Ciprofloxacin administered in the drinking water (200mg/kg per 24h) until day 9 in addition to CyA did not affect graft survival. However, when the same dose regimen was used in experiments with PVG rats as donors and Wistar/Kyoto as recipients, graft survival was significantly prolonged to a median of 45 days. Ciprofloxacin, given orally without the addition of CyA, did not influence graft survival in either of the two strain combinations. Thus, our data show that ciprofloxacin has no negative impact on heart graft survival rats. It remains to be clarified whether ciprofloxacin influences graft survival in humans.     

Prolongation of cardiac allograft survival in rats by anti-TNF and cyclosporine combination therapy.

Cyclosporine is well known to have many adverse side effects. However, while decreasing the dosage of CsA can reduce its toxicity, this also lowers its immunosuppressive effectiveness. Additionally, anti-tumor necrosis factor has been demonstrated to have immunosuppressive activity and been shown to prolong cardiac allograft survival. This current study therefore investigated the efficacy of a combined therapy of anti-TNF with low-dose CsA in a rat heterotopic cardiac transplant model utilizing Brown-Norway donors and Lewis recipients. Control transplant recipients received no immunotherapy. Experimental animals received single-dose anti-TNF intraperitoneally on posttransplant days 0, 3, or 5 and/or low-dose CsA (1.5 mg/kg/day) intramuscularly from days 0 to 14 after transplantation. Rejection was determined by the lack of contractions in the transplanted heart. No animal received any other form of immunosuppression. Graft survival was significantly prolonged with combination CsA and anti-TNF therapy, suggesting a synergistic effect against acute cardiac allograft rejection, possibly from CsA and anti-TNF interacting at different levels of the recipient immune response. This form of combination therapy may hold promise for future immunosuppressive techniques.     

应用羟基荧光素二醋酸琥珀酰亚胺脂探讨新型免疫抑制剂J2作用机制

目的探讨基于CIM立体构型设计的新型免疫抑制剂（J2）在小鼠体内的免疫抑制作用以及其作用机制。方法将羧基荧光素二醋酸琥珀酰亚胺酯（CFSE）标记的C57BL／6（H-2b）小鼠的淋巴细胞4×10^6～6×10^6经尾静脉注入经印钴照射（900拉德）后的DBA／2（H-2d）小鼠体内构建模型。将DBA／2小鼠随机分为5组，每组5只，模型建立后即刻腹腔注射J2，每天1次。对照组注射生理盐水、CsA组注射环孢素A（10mg／kg体重）；实验组J2A组（1mg／kg体重）、J2B组（4mg／kg体重）、J2C组（8mg／kg体重）。给药3d后分组处死DBA／2小鼠取脾制备淋巴细胞，用CD3、CD4、CD8单抗分别标记受检T细胞，FACS流式细胞仪检测CD4^＋T细胞和CD8^＋T细胞在小鼠体内分裂增殖的情况，并检测CD4^＋T细胞的凋亡情况。结果CFSE标记C57BL/6小鼠的脾淋巴细胞着染率大于99％。对照组分裂的CD4^＋T细胞（75．34±1．58）％、分裂的CD8^＋T细胞（83．48±1．25）％明显多于CsA组和实验组（P〈0．01）。J2B组和J2C组分裂的细胞数分别与CsA组比较差异无统计学意义（P〉0．05），但J2A组多于CsA组（P〈0．05）。对照组CD4^＋T细胞早期凋亡的比例（41．1±3．4）％明显高于其他各组（P〈0．01）。J2A组（35．6±4．1）％、J2B组（24．0±3．7）％和J2C组（13．6±2．3）％CD4^＋T细胞早期凋亡的比例显著高于CsA组（7．4±1．9）％（P〈0．05）。结论J2可能抑制T细胞亚群CD4^＋T细胞的活化，从而进一步抑制CD8^＋T细胞的分裂增殖而具有免疫抑制作用。     

供者骨髓基质干细胞输注延长大鼠移植心存活时间的探讨

目的 探讨供者骨髓基质干细胞(MSC)输注在大鼠同种心脏移植术后的免疫调节及延长移植心存活时间的作用.方法 供者为近交系Wistar大鼠,受者为Fisher 344大鼠.处死供者后抽取其股骨和胫骨中骨髓,分离和培养MSC.通过混合淋巴细胞试验观察不同密度的MSC对异源性T淋巴细胞增殖反应的抑制作用.建立大鼠异位心脏移植模型,根据处理方式的不同,将受者分为MSC输注组和对照组,每组8只.Msc输注组:将含有2×106个MSC的林格氏液分别于术前1周、术中及术后连续3 d经尾静脉注入受者体内;对照组:用与MSC输注组相同的方法在相同时间点注入不含MSC的林格氏液.术后第5天,采用实时逆转录聚合酶链反应检测移植心组织中细胞因子的表达情况.结果 供者MSC可明显抑制异源性T淋巴细胞的增殖反应,且MsC密度越高抑制作用越强.MSC输注组Th1类细胞因子白细胞介素(IL)-1β和γ干扰素的表达要显著低于对照组;MSC输注组Th2类细胞冈子IL-4和IL-10呈高表达,而对照组基本不表达.MSC输注组移植心平均存活时间为(12.4±5.3)d,与对照组的(6.4±2.0)d比较,差异有统计学意义(P＜0.01).结论 输注供者MSC可通过改变Th1/Th2类细胞因子的平衡向Th2偏移诱导受者产生免疫调节作用,从而延长移植心存活时间.     

Prolongation of rat skin and cardiac allograft survival by low molecular weight heparin.

BACKGROUND: We have previously reported that very low doses of low molecular weight heparin compounds (LMWH) inhibit a variety of T-cell-mediated reactions by down-regulation of TNF-alpha production. This study tested the efficacy of LMWH in organ transplantation. METHODS: Skin and heterotopic heart transplantations were performed between recipient Wistar rats and donor BN rats. Two doses of LMWH were given sc, 1 and 20 micrograms, each in three protocols, with day of grafting as Day 0: (A) Daily: -1, 0, 1 ellipsis, (B) Late Weekly: -1, 6, 13 ellipsis, and (C) Early Weekly: -7, 0, 7 ellipsis. Doses and schedules were selected based on efficacy in autoimmune models. Skin graft rejection was defined by complete separation of the graft, and heart transplant rejection was defined as cessation of heartbeat. RESULTS: Treatment with 1 microgram (26.8 +/- 2.0 days) and 20 micrograms (24.5 +/- 2.3 days) of LMWH using the Early Weekly protocol significantly prolonged skin allograft survival compared to controls (17.8 +/- 4.4 days), P < 0.001 for both, whereas other protocols did not. Compared to controls (8.3 +/- 1.4 days), treatment with both 1 and 20 micrograms of LMWH using all three protocols significantly prolonged cardiac allograft survival. The efficacy, however, varied considerably. Increase in graft survival ranged from 18% (1 microgram, Daily, 9.8 +/- 0.7 days, P = 0.02) to more than twofold (20 micrograms, Early Weekly, 20.8 +/- 5.5 days, P < 0.001) according to the dose and schedule of LMWH. CONCLUSIONS: Treatment with very low doses of nonanticoagulant LMWH preparations having anti-TNF-alpha activity significantly prolongs rat skin and cardiac allograft survival in a dose- and schedule-dependent manner.     

Prolongation of pancreatic allograft survival by 5-fluorouracil

Recipient survival in canine pancreatic allotransplantation was significantly prolonged when animals were treated with 5-fluorouracil in combination with low-dose azathioprine. Untreated dogs and those receiving only azathioprine survived for only short periods of time, and pancreatitis was frequently encountered. In contrast, animals treated with 5-fluorouracil were protected from pancreatitis and survived an average of almost three weeks.     

Synergism of the malononitrilamides 279 and 715 with cyclosporine A in the induction of long-term cardiac allograft survival

Abstract We tested here the effects of malononitrilamide (MNA) 279 and MNA 715 (derivatives of A771726, the active metabolite of leflunomide) in monotherapy and in combination with cyclosporine A (CSA) on heterotopically transplanted rat cardiac allografts (BN) [Brown Norway Lewis]. Both MNAs (5–20 mg/kg) displayed a dose-dependent increase of efficacy. The combination of CSA (5 mg/kg) with the MNAs (5 and 10 mg/kg) showed a synergistic effect in the prolongation of allograft survival and in the induction of long-term allograft survival. To investigate the immunological mechanism responsible for long-term allograft survival, we transplanted second set (BN) and third party (Dark Agouti) skin allografts on the tail of long-term surviving rats. The cause for long-term allograft survival turned out to be a donor-specific tolerance. We formulate a hypothesis for the mechanism of the synergism of the combination MNA + CSA in the induction of tolerance.