诱导型一氧化氮合酶抑制剂防治大鼠腹主动脉移植术后慢性排斥反应

目的研究移植物慢性排斥反应血管变化的机制,评价新型诱导型一氧化氮合酶(iNOS)抑制剂(FR260330)防治大鼠腹主动脉移植术后慢性排斥反应的作用。方法供者为ACI大鼠,受者为Lewis大鼠。采用原位腹主动脉移植,移植后2周和12周时分别处死受者,取其移植腹主动脉,用光学显微镜及计算机图像分析系统分析腹主动脉内膜、平滑肌及外膜的面积及内膜/内膜 中层比例。并以α肌动蛋白(αactin)免疫组织化学法进行内膜、中层细胞成份分析。术后分别单独或联合应用FR260330和他克莫司(FK506)抗排斥反应。结果移植后用iNOS抑制剂组3个月时血管内膜/内膜 中层比例明显小于不用药对照组;移植后不用药对照组及用FK506组的血管中层细胞均出现不同程度破坏;用iNOS抑制剂组的血管内膜比用FK506组更光滑,破坏情况也较少。结论iNOS抑制剂对慢性排斥反应有抑制作用。     

热休克蛋白70在大鼠肝移植急性排斥反应中的表达及意义

目的 探讨热休克蛋白70(HSP70)在大鼠肝移植术后的表达规律及对急性排斥反应的早期诊断意义.方法 采用改良"二袖套法"建立大鼠原位肝移植模型.随机将大鼠分为3组,每组供、受者各15只.对照组:供、受者均采用Wistar大鼠;未治疗组:供者为SD大鼠,受者为Wistar大鼠,肝移植后不用任何免疫抑制剂;治疗组:供者为SD大鼠,受者为Wistar大鼠,肝移植术后肌肉注射他克莫司(FK506)2 mg·kg-1·d-1.每组分别于术后第3、5、7天随机各处死5只受者,取移植肝脏观察组织病理学变化,免疫组织化学及逆转录聚合酶链反应(RT-PCR)检测移植肝HSP70的表达,并分析其与急性排斥反应的相互关系.结果 对照组术后无排斥反应发生;未治疗组术后第3天出现典型的排斥反应病理变化,随术后时间推移,排斥反应活动度积分(RAI)逐渐升高(P<0.05);治疗组表现为无排斥反应或交界性排斥反应.对照组移植肝HSP70的表达在术后出现短暂升高后迅速降低(P<0.05),未治疗组移植肝HSP70的表达水平较对照组高,并随术后时间的推移而逐渐升高(P<0.01),与移植肝RAI之间存在着明显的正相关(P<0.01);治疗组移植肝组织HSP70在术后各时间段均呈低表达.结论 移植肝组织中HSP70的表达与急性排斥反应的发生和发展密切相关;HSP70表达升高对早期诊断急性排斥反应有一定的意义.     

输注供者CD8+CD28-调节性T淋巴细胞抑制大鼠肝移植急性排斥反应的作用

目的 评价具有免疫抑制作用的CD8+CD28-调节性T淋巴细胞(Treg)体内输注在抑制大鼠肝移植急性排斥反应中的作用.方法 建立近交系大鼠肝移植自发耐受及急性排斥反应模型.从肝移植自发耐受模型受者脾脏中分离CD8+CD28-Treg,于急性排斥反应模型建立前1 d输注给受者,比较不同的输注组间受者的存活时间和移植肝病理学表现.结果 来自自发耐受模型(LEW大鼠为供者,DA大鼠为受者)的CD8+CD28-Treg输注可以延长急性排斥反应模型(LEW大鼠为供者,BN大鼠为受者)受者的存活时间,由(14.0±2.2)d延长至(24.0±3.0)d(P＜0.01),移植肝病理学显示排斥反应程度减轻.结论 大鼠肝移植自发耐受模型受者体内诱导的CD8+CD28-Treg具有抑制急性排斥反应的作用,该免疫抑制作用具有抗原特异性.     

RNA编辑酶ADAR1在大鼠肝移植排斥反应中的变化

目的观察RNA编辑酶ADAR1在大鼠肝移植排斥反应中的表达变化。方法实验分为4组①同基因移植组(n=15),取Wistar大鼠的肝脏原位移植给Wistar大鼠;②异基因移植组(n=15),取SD大鼠的肝脏移植给Wistar大鼠;③异基因移植 FK506治疗组(n=15),取SD大鼠的肝脏移植给Wistar大鼠,术后肌注FK506,2mg/(kg·d);④对照组(n=15),对Wistar大鼠不行肝移植,仅行开、关腹手术。建立大鼠原位肝移植模型,分别于术后第3、5及7d各处死5只大鼠,取脾脏组织,用RT-PCR方法检测ADAR1 mRNA的表达变化。结果移植后各组大鼠肝脏、脾脏病理变化随时间发展而呈进行性变化,异基因移植组病理变化最明显。ADAR1 mRNA表达在异基因移植组的各个时相点明显高于同基因移植组和异基因移植 FK506治疗组(P<0.001),于第5d时最明显。结论在大鼠原位肝移植发生急性排斥反应时,ADAR1增高程度与排斥反应的强度变化趋势一致。FK506可以抑制ADAR1的表达,明显减轻移植肝组织的急性排斥反应。     

一氧化氮(NO)合酶和NO在延迟性异种移植排斥反应中的作用

目的利用小鼠至大鼠异位心脏移植模型,研究诱导性一氧化氮合酶(iNOS)和受体血清一氧化氮(NO)在延迟性异种移植排斥反应(DXR)中的作用.方法将大鼠随机分为4组A组(6只),空白对照;B组(5只),来氟米物(Lef)+环孢素A(CsA);C组(6只),氨基胍;D组(6只),氨基胍+Lef+CsA.利用免疫组织化学染色检测CD68和NOS2,原位杂交技术检测iNOS mRNA表达.于移植前3 d和移植心脏排斥时分别采集血清检测NO含量.结果所有被排斥心脏中均见巨噬细胞(MФ)浸润,Lef+CsA显著延长移植心脏存活(与A和C组相比,P＜0.05),单用氨基胍使移植心脏存活(3 83±1.47)d(与A组比较,P＜0.05),氨基胍联用Lef和CsA使移植心脏存活(8.67±1.76)d(与A、B和C组比较,P＜0.05).发生DXR时浸润的MФ均有NOS2蛋白和mRNA阳性表达,且不受氨基胍影响.发生DXR时大鼠血清NO水平较移植前显著升高(P＜0.01),氨基胍可显著降低排斥时NO水平.结论小鼠至大鼠心脏移植发生DXR时浸润的MФ表达iNOS增多,且血清NO升高.抑制iNOS活性,降低NO水平可显著延长移植物存活时间,提示iNOS和NO是DXR发生的可能机制之一.     

TLSFJM联合小剂量FK506促进大鼠小肠移植耐受

目的 探讨TLSFJM(JM急性T淋巴细胞白血病细胞分泌的抑制因子)作为抑制因子对小肠移植急性排斥反应的抑制效应及其机理,并与FK506的抑制效应特点和副作用进行比较分析.方法 雄性BN和LEW大鼠分别作为供、受体行小肠移植,共分5组 小肠移植组(SBT组)、大剂量FK506 [0.5 mg/(kg·d)]组、小剂量FK506 [0.25 mg/(kg·d)]组、TLSFJM [10 U/(kg·d)]组和FK506 [0.25 mg/(kg·d)] TLSFJM [10 U/(kg·d)]组.FK506和TLSFJM分别以肌肉或腹腔注射方式给药.在不同时间段分别观察各组动物体重、生存时间及肝、肾功能,组织病理学检查排斥反应发生情况.结果 TLSFJM应用7 d,对移植大鼠肝、肾功能无损害.TLSFJM 小剂量FK506不但避免了大剂量FK506对肝功能的损害,而且显著延长了受体的生存时间.但单独应用TLSFJM仍有一定程度排斥反应出现,不能明显延长受体的生存时间.结论 TLSFJM作为一种有效的移植免疫抑制因子,联合小剂量FK506应用能延长宿主和移植肠的生存时间,延缓排斥反应的发生,减轻排斥反应的强度,避免大剂量FK506治疗带来的并发症.TLSFJM有望成为一种新型、高效、低毒的免疫抑制剂.     

自发免疫耐受大鼠移植肝内调节性T细胞的生物学特性

目的研究大鼠肝移植后自发免疫耐受的形成与移植肝内CD4~ CD25~ 调节性T细胞(Tr细胞)的关系。方法按供、受者不同将实验分为3组。急性排斥组:DA大鼠为供者,LEW大鼠为受者;自发耐受组:LEW大鼠为供者,DA大鼠为受者;同基因组:供、受者均为DA大鼠。各组均建立大鼠原位肝移植模型。分别在肝移植术后4、7、14、30和90 d时采用密度梯度离心法分离移植肝内淋巴细胞,免疫磁珠分离(MACS)法分选出CD4~ CD25~ Tr细胞;用流式细胞术(FCM)检测细胞纯度,同时分析CD4~ CD25~ Tr细胞比例的变化;体外细胞增殖试验研究CD4~ CD25~ Tr细胞对CD4~ CD25~-T细胞的免疫抑制作用。结果肝移植早期,急性排斥组和自发耐受组移植肝内CD4~ CD25~ Tr细胞比例均明显增加,其中急性排斥组增加更为明显;移植后4 d左右,两组CD4~ CD25~ Tr细胞比例开始下降,急性排斥组的下降幅度较大;移植后30 d,自发耐受组受者的移植肝内CD4~ CD25~ Tr细胞比例达到第2次高峰,约在移植后90 d时下降至正常生理水平。移植后7 d左右,急性排斥组受者均因发生排斥反应而死亡,而自发耐受组受者均存活。此外,CD4~ CD25~ Tr细胞能有效抑制CD4~ CD25~-T细胞的增殖。结论CD4~ CD25~ Tr细胞是一种具有特异免疫调节功能的T细胞亚群,其主动的免疫抑制功能可能是诱导大鼠肝移植自发免疫耐受的机制之一。     

DA与Lewis大鼠品系组合建立大鼠肝移植排斥与耐受模型

目的 建立大鼠原位肝脏移植急性排斥与自然耐受模型.方法 采用近交系雄性DA大鼠与Lewis大鼠互为供受体,改良"二袖套"法建立大鼠原位肝脏移植(rat orthotopic liver trans-plantation,ROLT)模型84例.实验分为4组:排斥组(DA→Lewis,n=12),FK506处理排斥组[DA→Lewis,n=24,术后1～7 d用FK506 0.2 mg/(kg·d)灌胃],耐受组(Lewis→DA,n=24),同基因组(DA→DA,n=24).各组中随机取6例观察生存期,其余分别于术后7、14、28 d处死6例,收集外周血及肝脏标本.检测血清标本天冬氨酸转氨酶(aspartate aminotransferase,AST)、总胆红素(total bilirubin,TBIL)浓度,病理学检查移植物排斥反应程度.结果 排斥组中位生存时间(median surviv-al time,MST)为12 d,而FK506处理排斥组MST为76 d,较排斥组明显延长(vs排斥组,P<0.01).耐受组与同基因组的MST均>120 d.术后7 d,排斥组血清AST、BILI浓度均明显高于其余3组(P<0.05);术后14 d,FK506处理组、耐受组和同基因组血清AST、TBIL浓度无明显差异.术后28 d,FK506处理组血清AST、TBIL浓度较耐受组和同基因组明显升高(P相似文献   

小肠移植急性排斥反应中bcl-2及bax表达的意义

目的探讨bcl-2及bax的异常表达与小肠移植急性排斥反应的关系。方法选用近交系F344/N和封闭群Wistar/A大鼠建立同种异基因小肠移植模型,并随机分为同基因移植组、异基因移植组、异基因加普乐可复(FK506)治疗组和对照组,用免疫组织化学技术检测36只大鼠术后移植肠组织中bcl-2及bax在移植肠组织中的表达。结果异基因组术后第3天,bcl-2的表达显著低于对照组(P<0.05),并随着移植天数的增加,差异更加具有显著性意义(P<0.01);bax的表达与对照组比较差异无显著性意义(P>0.05);FK506治疗组bcl-2及bax表达与对照组比较,差异均无显著性意义(P>0.05)。结论移植肠组织内bcl-2表达水平可作为早期诊断急性排斥反应的一个有参考意义的指标。     

TNF-α和IL-10在非协调性异种肝移植中的作用探讨

目的 探讨细胞因子TNF－α和IL－10在异种肝移植中的作用。方法 建立豚鼠到大鼠原位肝移植模型，用RT－PCR方法检测移植肝内TNF－αmRNA和IL－10 mRNA的表达，并通过应用FK506改变上述细胞因子mRNA的表达探讨其不同作用。结果 非协调性异种肝移植后移植肝内有TNF－αmRNA和IL－10mRNA的表达，FK506可以上调IL－10 mRNA的表达并下调TNF－αmRNA的表达，并减轻受体超急性排斥反应的程度。结论 细胞因子在异种肝移植的免疫排斥反应中有重要作用，抗炎和促炎因子的平衡对排斥反应有缓和作用。     

Increased iNOS-expressing macrophage in long-term surviving rat small-bowel grafts

BACKGROUND: Inducible nitric oxide synthase (iNOS) produces nitric oxide and modulates many biologic processes critical in the development of rejection; however, its role in chronic rejection (CR) in small-bowel transplantation (SBT) is largely unknown. METHODS: FK506 prevented acute rejection (AR); however, recipients eventually lost their bowel grafts to CR. Combined FK506 and rapamycin treatment prevented CR, thus leading to long-term graft survival. We investigated iNOS expression in our rat orthotopic SBT CR model. RESULTS: Histologically, mesentery vascular occlusion and fibrosis, which are hallmarks of CR, were apparent in bowel grafts in an FK506 single-treatment group. In contrast, patients with long-term surviving grafts receiving FK506 and rapamycin developed mild vascular occlusion and fibrosis. Unlike in AR, low iNOS expression, which is associated with decreased macrophage infiltration, was observed in CR grafts. However, iNOS expression and macrophage infiltration was higher in long-term-surviving grafts than CR grafts. Immunofluorescence staining revealed that the majority of macrophages expressed iNOS in long-term surviving grafts. COMMENTS: Sequential treatment combining FK506 and rapamycin prolonged survival of SBT animals with decreased vasculopathy and collagen deposition of the intestinal grafts. iNOS may play opposing roles in AR and CR in SBT.     

“Tolerogenic effect” of the liver for a small bowel allograft

Abstract A newly developed liver/small bowel transplantation model (LSBTx) was used to investigate the tolerogenic effect of a liver allograft toward a simultaneously transplanted small bowel. Small bowel transplantation (SBTx) under high‐dose immunosuppression was compared to LSBTx with a lower FK506 dosage. Syngeneic Lewis [(LEW) to LEW] and two fully allogeneic rat strain combinations (Brown Norway‐to‐LEW and Dark Agouti‐to‐LEW) were used. Clinical course and histological findings after SBTx demonstrated a chronic rejection of the small bowel allograft within 100 days. However, after LSBTx long‐term acceptance (> 150 days) was achieved after a transient rejection crisis, although initial immunosuppression was significantly lower. Furthermore, indicator heart transplantations demonstrated the induction of donor‐specific tolerance in both allogeneic strain combinations. In contrast to other LSBTx rat models, these results reflect observations after human LSBTx, in which the rate of acute and chronic rejection is also significantly lower than after human SBTx.     

Protective effects of PG490-88 on chronic allograft rejection by changing intragraft gene expression profiles

Our previous study showed that PG490-88 effectively ameliorated both functional and histological changes of chronic rejection in the rat. In this experiment, we investigated the intragraft gene expression profiles of PG490-88 under successful prevention of chronic rejection in rat kidney allografts. Kidneys of F344 rats were transplanted into bilaterally nephrectomized LEW recipients. Recipients with a brief course of low-dose FK506 (1 mg/kg per day for 10 days) were dosed with PG490-88 0.5 mg/kg per day, which was predetermined and defined as the effective dose of preventing chronic allograft rejection in this model, for 90 days after grafting. Kidney grafts were harvested on day 90 after transplantation and subjected to gene expression analysis by real-time RT-PCR. Overall, the expression levels of all genes tested were upregulated in the brief course of low-dose FK506 control. PG490-88 treatment exhibited significant inhibition of intragraft m RNA levels of iNOS, IL-6, and perforin and marginal downregulation of IL-2, IFNgamma, IRF-1, TNFalpha, and TGFbeta. There was no change in IL-10, granzyme B, and PDGFalpha, when compared to the brief course of low-dose FK506 control. These results suggested that downregulation of multiple intragraft gene expression by mainly suppression of iNOS, IL-6, and perforin might be responsible for successful prevention of chronic kidney allograft nephropathy by PG490-88 in rats.     

Focus on intractable rejection: 6-month results of the European multicentre liver study of FK 506 and cyclosporin A

Abstract The incidence of intractable rejection was evaluated during the course of a multicentre, randomised, parallel-group study comparing the efficacy and safety of FK 506 and conventional cyclosporin A-based immunosuppressive regimens in patients undergoing primary liver transplantation. A diagnosis of intractable rejection was made if there was histological evidence of unchanged or worsening acute rejection, or chronic rejection after two discrete courses of antirejection therapy. Antirejection regimens were specific to each centre. Patients who experienced intractable rejection could be withdrawn from the study. Patients who were withdrawn from the cyclosporin A treatment group could subsequently receive FK 506 therapy and vice-versa. Intractable rejection was diagnosed in 32/540 patients (5.9%): 7/267 patients (2.6%) in the FK 506 treatment group and 25/273 patients (9.2%) receiving cyclosporin A therapy ( P < 0.01). Of these 32 patients, 25 were withdrawn from the study: 3 and 22, from the FK 506 and cyclosporin A treatment groups, respectively. All three patients withdrawn from the FK 506 treatment group are alive: two having undergone retransplantation. Of the 22 patients withdrawn from the cyclosporin A group and converted to FK 506 therapy, 6 were retransplanted, 4 of whom subsequently died. A further two patients died without retransplantation. Thus, in 14 of the 16 patients who were still alive at 6 months, the liver graft was saved after conversion to FK 506 treatment. The reduced incidence of intractable rejection in patients receiving treatment with FK 506, together with the successful rescue of patients developing intractable rejection while receiving cyclosporin A, suggests that FK 506 is an effective immunosuppressive agent following orthotopic liver transplantation.     

肝、胰Ⅰ期联合移植治疗合并糖尿病的良性终末期肝病一例

目的 对1例原位肝、异位胰腺I期联合移植进行总结.方法 对1例终末期肝病合并2型糖尿病的患者施行肝、胰I期联合移植,肝脏为原位移植,胰腺异位移植于右侧髂窝,胰液空肠引流.术后采用他克莫司、霉酚酸酯及糖皮质激素预防排斥反应,并辅以两剂达利珠单抗.结果 术后移植胰腺功能良好,第2天即停用胰岛素.术后14 d,移植肝出现轻度急性排斥反应,调整他克莫司的用量后逆转.受者已存活15个月,移植肝脏及胰腺功能均正常.结论 肝、胰联合移植是治疗终末期肝病合并糖尿病的有效方法.     

Mucosal glutamine utilization after small-bowel transplantation: an electrophysiologic study.

A short course of FK 506 after small bowel transplantation averts rejection in the rat and achieves indefinite survival of the recipient whose nutritional status is dependent on the function of the intestinal graft. Ex vivo electrophysiologic studies using the Ussing Cell were conducted to delineate functional competence of the graft by evaluating mucosal ion transport and glutamine utilization. Orthotopic small-bowel transplantation was performed in Lewis (LEW) rats as recipients of either Brown-Norway (BN) allografts or LEW syngeneic grafts. Allograft recipients received FK 506 either as a short course (2 mg/kg on Day 0-4 after transplantation) or continuously (2 mg/kg Day 0-4, then 0.5 mg/kg weekly). Ileal mucosa was harvested from small bowel grafts 9 and 60 days after transplantation and mounted in the Ussing Cell containing Hanks' balanced salt solution with/without L-glutamine (20 mM). Transmembrane potential difference (PD), which represents mucosal active ion transport, and mucosal resistance, an index of membrane integrity, were recorded. Nine days after transplantation, mucosal PD was the same in the ileum from syngeneic grafts, allografts treated with FK 506 and normal LEW and BN rats, and the addition of glutamine increased PD equally in all groups. In comparison, PD was markedly decreased in allografts undergoing rejection, and the glutamine response was blunted. Sixty days after transplantation, mucosal PD was reduced in allografts treated with a short course of FK 506, but normal in allografts receiving continuous immunosuppression with FK 506 and in syngeneic grafts. A decrease of mucosal resistance was not a feature of rejection nor a sequel of limited FK 506 therapy. Our data indicate that allograft rejection results in a significant decrease in mucosal PD and a poor response to glutamine. Control of rejection by FK 506 preserves normal electrophysiologic responses of the allograft mucosa.     

FK778 controls acute rejection after rat liver allotransplantation showing positive interaction with FK506

This study including prevention and rescue experiments was performed to examine the efficacy of FK778 and its interactions with FK506. In the prevention experiment, Brown-Norway rats transplanted with a 7 Lewis livers received day-course of FK778 or a combination of FK778 and FK506 treatment. For the rescue experiment, the recipients were additionally treated with FK778 from days 7 to 13. Blood chemistry and histopathological findings were used to examine the host and the graft condition. Donor-specific IgM was measured using enzyme-linked immunosorbent assays. The serum trough level of FK778 was examined by high-performance liquid chromatography. FK778 suppressed acute rejection in a dose-dependent manner. The optimal FK778 dosage was 20 mg/kg body weight (BW) d. FK778 treatment from days 7 to 13 rescued liver grafts from ongoing rejection. The combination of FK506 (0.125 mg/kg BW/d) and FK778 (20 mg/kg BW/d) maintained better graft condition than FK778 (20 mg/kg BW/d) monotherapy. In conclusion, FK778 prevents acute rejection in and rescues transplant recipients from ongoing rejection after rat liver transplantation. The optimal monotherapy dosage of FK778 was 20 mg/kg BW/d. Combination therapy with FK506 was more beneficial than FK778 monotherapy.     

FK778 and FK506 combination therapy to control acute rejection after rat liver allotransplantation

BACKGROUND: In organ transplantation, several immunosuppressants are currently used to control graft rejection. Clinically, no single immunosuppressive agent can completely prevent posttransplantation immunoreaction; thus, combination therapy is usually performed. Novel agents with more powerful immunosuppressive activity and less toxicity need to be developed. METHODS: Lewis rat livers were orthotopically transplanted into Brown-Norway recipients. FK778 was administered orally from day 0 to day 6 to prevent acute rejection and from day 7 to day 13 to rescue ongoing rejection. To assess the combined effects, recipients were treated with intramuscular injection of FK506 and oral administration of FK778 from day 0 to day 6. Blood chemistry and histopathologic findings were measured to determine the patient's general condition and the graft condition. Allospecific antibodies were measured using enzyme-linked immunosorbent assays. The FK778 trough concentration was examined by using high-performance liquid chromatography. RESULTS: The acute immune response was suppressed by FK778 alone in a dose-dependent manner. The optimal FK778 dosage was determined to be 20 mg/kg per day, because adverse effects (weight loss and intestinal bleeding) occurred at 30 mg/kg per day. FK778 treatment from day 7 to day 13 rescued liver grafts from ongoing rejection. The intramuscular FK506 (0.125 mg/kg per day) injection and the oral FK778 (20 mg/kg per day) gavages suppressed acute liver graft rejection effectively and maintained better graft condition compared with monotherapy. CONCLUSIONS.: FK778 treatment effectively prevented acute rejection and rescued ongoing rejection after liver transplantation. The optimal dosage was determined to be 20 mg/kg per day. Combination therapy with FK506 was more beneficial than FK778 monotherapy.     

Effects of inhaled FK 506 on the suppression of acute rejection after lung transplantation: use of a rat orthotopic lung transplantation model.

BACKGROUND: FK 506 inhalant was recently developed for localized administration. We investigated its effects on acute lung allograft rejection and compared its efficacy with that of intramuscular administration of FK 506. METHODS: Rats (n = 123) with orthotopic left lung transplantation were divided into 9 groups. Six groups inhaled FK 506 (5 puffs, 10 puffs or 20 puffs per day), or were given intramuscular administration of FK 506 (0.05, 0.1 or 1.0 mg/kg/day). The other groups included rats receiving an isograft, rats with an untreated allograft, and a placebo group. All groups (n = 6 each) were monitored for 14 days post-operatively as an end-point and graft survival time was determined. The remaining animals were killed 4 days after transplantation. The histologic grade of rejection was determined for all groups (n = 6 each). With both (n = 3 each) inhalation therapy and intramuscular administration of FK 506, which showed similar degrees of effectiveness, both blood FK 506 concentration and cytokine expression in the graft and spleen were evaluated. RESULTS: FK 506 inhalation therapy extended allograft survival time and reduced histologic rejection on Day 4 in all groups. Graft survival time and histologic rejection scores at a dose of 10 puffs/day were comparable to those with 0.1 mg/kg/day of intramuscular FK 506. Trough concentrations of FK 506 in blood were detectable with 0.1 mg/kg/day of intramuscular FK 506, but not with 10 puffs/day. The messenger RNA expression levels of interferon-gamma in the lung allograft was suppressed significantly at a dose of 10 puffs/day. CONCLUSIONS: FK 506 inhalant enhances acute lung allograft survival with lower blood concentrations than when using comparable intramuscular administration.