Donor liver natural killer cells alleviate liver allograft acute rejection in rats

BACKGROUND:Liver enriched natural killer (NK) cells are of high immune activity.However,the function of donor liver NK cells in allogeneic liver transplantation (LTx) remains unclear.METHODS:Ten Gy of whole body gamma-irradiation (WBI) from a 60 Co source at 0.6 Gy/min was used for depleting donorderived leukocytes,and transfusion of purified liver NK cells isolated from the same type rat as donor (donor type liver NK cells,dtl NKs) through portal vein was performed immediately after grafting the irradiated liver.Post-transplant survival observation on recipients and histopathological detection of liver grafts were adoptive to evaluate the biological impact of donor liver NK cells on recipients’ survival in rat LTx.RESULTS:Transfusion of dtl NKs did not shorten the survival time among the recipients of spontaneous tolerance model (BN to LEW rat) after rat LTx,but prolonged the liver graft survival among the recipients depleted of donor-derived leukocytes in the acute rejection model (LEW to BN rat).Compared to the recipients in the groups which received the graft depleted of donor-derived leukocytes,better survival and less damage in the allografts were also found among the recipients in the two different strain combinations of liver allograft due to transfusion of dtl NKs.CONCLUSIONS:Donor liver NK cells alone do not exacerbate liver allograft acute rejection.Conversely,they can alleviate it,and improve the recipients’ survival.

Metronomic capecitabine inhibits liver transplant rejection in rats by triggering recipients’T cell ferroptosis

BACKGROUND Capecitabine(CAP)is a classic antimetabolic drug and has shown potential antirejection effects after liver transplantation(LT)in clinical studies.Our previous study showed that metronomic CAP can cause the programmed death of T cells by inducing oxidative stress in healthy mice.Ferroptosis,a newly defined non-apoptotic cell death that occurs in response to iron overload and lethal levels of lipid peroxidation,is an important mechanism by which CAP induces cell death.Therefore,ferroptosis may also play an important role in CAP-induced T cell death and play an immunosuppressive role in acute rejection after transplantation.AIM To investigate the functions and underlying mechanisms of antirejection effects of metronomic CAP.METHODS A rat LT model of acute rejection was established,and the effect of metronomic CAP on splenic hematopoietic function and acute graft rejection was evaluated 7 d after LT.In vitro,primary CD3+T cells were sorted from rat spleens and human peripheral blood,and co-cultured with or without 5-fluorouracil(5-FU)(active agent of CAP).The levels of ferroptosis-related proteins,ferrous ion concentration,and oxidative stress-related indicators were observed.The changes in mitochondrial structure were observed using electron microscopy.RESULTS With no significant myelotoxicity,metronomic CAP alleviated graft injury(Banff score 9 vs 7.333,P<0.001),prolonged the survival time of the recipient rats(11.5 d vs 16 d,P<0.01),and reduced the infiltration rate of CD3+T cells in peripheral blood(6.859 vs 3.735,P<0.001),liver graft(7.459 vs 3.432,P<0.001),and spleen(26.92 vs 12.9,P<0.001),thereby inhibiting acute rejection after LT.In vitro,5-FU,an end product of CAP metabolism,induced the degradation of the ferritin heavy chain by upregulating nuclear receptor coactivator 4,which caused the accumulation of ferrous ions.It also inhibited nuclear erythroid 2 p45-related factor 2,heme oxygenase-1,and glutathione peroxidase 4,eventually leading to oxidative damage and ferroptosis of T cells.CONCLUSION Metronomic CAP can suppress acute allograft rejection in rats by triggering CD3+T cell ferroptosis,which makes it an effective immunosuppressive agent after LT.

EXPRESSION OF ICAM-1 AND LFA-1 MOLECULES IN RELATION TO RENAL ALLOGRAFT REJECTION IN RATS

Objective.The purpose of this study was to assess the renal graft expression of ICAM 1(intercellular adhesion molecule 1) and LFA 1(lymphocyte function associated antigen 1)molecule with relation to graft rejection. Methods.Rat kidney transplantation was performed according to the procedure of Kamada with some modification.Experimental rats were divided into 5 groups.The survival time of recipient rats and function of grafts after renal transplantation were observed.The sections of renal graft were stained for monoclonal antibody ICAM 1 and LFA 1, and then quantification of ICAM 1 and LFA 1 expression was accomplished by computer image analysis. Results.ICAM 1 and LFA 1 increased significantly in the renal allograft rejection group as compared with the non rejection groups(P<0 05). Conclusion.Both biopsy of renal graft and monitoring of ICAM 1 and LFA 1 are useful tools in diagnosing and treating acute rejection.

Studies on the Effects of the Immunosuppressant FK-506 on the High-risk Corneal Graft Rejection

Purpose: To evaluate the clinical efficacy of FK-506 on suppressing high-risk cornea transplantation rejection.Methods: In a randomized controlled clinical trial, 56 eyes of 56 patients with high-risk keratoplasty (including total corneal transplantation TCT, total corneal transplantation with circular lamellar sclera CST, vascularization corneal transplantation and corneal retransplantation) were divided into the experimental group and the control group(each with 28 eyes).The experimental group was treated by FK-506 eyedrops (0.5 mg/ml) and TobraDex eyedrops, compared with the control group that was treated by 1% CsA eyedrops and TobraDex eyedrops. In the average 8.1-month follow-up period, the visual acuity, graft transparent duration and Rejection Index (RI) of grafts were observed. Results: In the follow-up period, the graft rejection rate of the experimental and the control group was 63.6% and 95.2% respectively (χ2＝4. 72, P ＜ 0. 05) with significant difference.Conclusions: The local application of FK-506 suppressed effectively the graft rejection of corneal transplantation of the patients at high risk.

Lymphocyte infiltration and activation in iris-ciliary body and anterior chamber of mice in corneal allograft rejection

AIM: To investigate the infiltration and activation of lymphocyte in iris-ciliary body and anterior chamber after allogenic penetrating keratoplasty (PK), for further revealing the role of iris-ciliary body in corneal allograft immune rejection. METHODS: In the mice models of PK, BALB/C mice received orthotopic isografts (n =35) or C57BL/6 donor allografts (n=25). Grafts were examined daily for 3 weeks by slit-lamp microscopy and scored for opacity. The infiltration of CD4(+) T lymphocyte in iris-ciliary body and anterior chamber was examined by immunohistology and the mRNA of CD80 and CD86 in both cornea graft and iris-ciliary body by RT-PCR was analyzed in allograft recipient at days 3, 6, 10 and the day when graft rejection occurred. Isograft recipients were examined as control at the corresponding time points. Transmission electron microscope was used to study the ultrastructure, especially cell infiltration, of iris-cilary body and corneal graft at day 3, 7 and the day when rejection occurred after allogenic PK. RESULTS: Rejection was observed in all the allograft recipients followed more than 10 days, at a median time of 15 days (range 12-18 days), but not in any of isografts. CD4(+) T cells were first detected at day 6 after transplantation in limbus and Ciliary body, and then in the stroma of recipient, iris, anterior chamber and corneal allograft with an increased number until graft rejection occurred. CD80 and CD86 mRNA were detected under RT-PCR examination in both graft and iris-ciliary body of allograft recipient, but not in any of isograft recipient. Three days after operation, lymphocytes and monocytes macrophages were visible in iris blood vessels and the anterior chamber, and vascular endothelial cell proliferation and activation were significant under transmission electron microscopy examination. At day 7, corneal endothelial cells became thinner. Lymphocytes and mononuclear macrophages were found with great number in the anterior chamber and adhered to the corneal endothelium. Blood vessels in iris increased and were filled with lymphocytes. And lymphocytes were detected to migrate through endothelial cell gap out of vessels. When allograft rejection occurred, macrophages attached to endothelial cells with large number of lymphocytes and macrophages infiltrating in iris. CONCLUSION: Lymphocyte infiltration and activation occurred in iris-ciliary body after allogenic PK, and the lymphocytes could migrate from iris blood vessel to the anterior chamber, which might play an important role in corneal allograft immune rejection.

Role of biliary complications in chronic graft rejection after living donor liver transplantation

Postoperative biliary complications remain a substantial challenge after living donor liver transplantation,especially due to its heterogeneous clinical presentation.

Preservation of donor's heart and lung and discrimination and postoperative immunotherapy of graft rejection:a report of 2 cases of heart-lung transplantation

Objective To summarize preservation measures of donor’s heart and lung,and postoperative imrnunotherapy,as well as clinical experience of discrimination and management for graft rejection. Methods Clinical data of 2 cases of heart - lung transplantation in our depart-

Chronic rejection after liver transplantation:Opening the Pandora’s box

Chronic rejection(CR)of liver allografts causes damage to intrahepatic vessels and bile ducts and may lead to graft failure after liver transplantation.Although its prevalence has declined steadily with the introduction of potent immunosuppressive therapy,CR still represents an important cause of graft injury,which might be irreversible,leading to graft loss requiring re-transplantation.To date,we still do not fully appreciate the mechanisms underlying this process.In addition to T cell-mediated CR,which was initially the only recognized type of CR,recently a new form of liver allograft CR,antibody-mediated CR,has been identified.This has indeed opened an era of thriving research and renewed interest in the field.Liver biopsy is needed for a definitive diagnosis of CR,but current research is aiming to identify new non-invasive tools for predicting patients at risk for CR after liver transplantation.Moreover,the minimization or withdrawal of immunosuppressive therapy might influence the establishment of subclinical CR-related injury,which should not be disregarded.Therapies for CR may only be effective in the“early”phases,and a tailored management of the immunosuppression regimen is essential for preventing irreversible liver damage.Herein,we provide an overview of the current knowledge and research on CR,focusing on early detection,identification of non-invasive biomarkers,immunosuppressive management,re-transplantation and future perspectives of CR.

Role for urinary biomarkers in diagnosis of acute rejection in the transplanted kidney

Despite the introduction of potent immunosuppressive medications within recent decades, acute rejection still accounts for up to 12% of all graft losses, and is generally associated with an increased risk of late graft failure. Current detection of acute rejection relies on frequent monitoring of the serum creatinine followed by a diagnostic renal biopsy. This strategy is flawed since an alteration in the serum creatinine is a late clinical event and significant irreversible histologic damage has often already occurred. Furthermore, biopsies are invasive procedures that carry their own inherent risk. The discovery of non-invasive urinary biomarkers to help diagnose acute rejection has been the subject of a significant amount of investigation. We review the literature on urinary biomarkers here, focusing on specific markers perforin and granzyme B m RNAs, FOXP3 m RNA, CXCL9/CXCL10 and mi RNAs. These and other biomarkers are not yet widely used in clinical settings, but our review of the literature suggests that biomarkers may correlate with biopsy findings and provide an important early indicator of rejection, allowing more rapid treatment and better graft survival.

Proteomics for rejection diagnosis in renal transplant patients: Where are we now?

Rejection is one of the key factors that determine the long-term allograft function and survival in renal transplant patients. Reliable and timely diagnosis is important to treat rejection as early as possible. Allograft biopsies are not suitable for continuous monitoring of rejection. Thus, there is an unmet need for non-invasive methods to diagnose acute and chronic rejection. Proteomics in urine and blood samples has been explored for this purpose in 29 studies conducted since 2003. This review describes the different proteomic approaches and summarizes the results from the studies that examined proteomics for the rejection diagnoses. The potential limitations and open questions in establishing proteomic markers for rejection are discussed, including ongoing trials and future challenges to this topic.

Mycophenolate Mofetil with Low Dose CsA for Chronic Rejection in Primary Cadaveric Renal Recipients

Objective To investigate the clinical efficacy of mycophenolate mofetil(MMF) with low dose CsA for chronic rejection in primary cadaveric renal recipients. Methods A total of 8 renal recipients who were clinically diagnosed as chronic rejection were given triimmunosuppressive agents: MMF 1.5~2.0 g/d+ CsA 2 to 3 mg/kg·d -1 and pred 10 mg/d.Results Blood creatinine reduced to normal level and urine protein disappeared in five cases, blood creatinine and urine protein decreased obviously in two cases, and kidney function deteriorated in another patient 4 to 9 weeks after this strategy. No acute rejection episodes or liver damage occurred among these patients during treatment. White blood cells reduced in one case, but it improved after therapy. Conclusion MMF combined with low dose CsA can bring a considerable efficacy in reversing chronic rejection of renal recipients. This immunosuppressive strategy may be a useful routine in the treatment of chronic rejection.

Correlation between tumor necrosis factor a gene promoter polymorphisms and acute rejection following renal transplantation

Objective To study the significance of cytokine tumor necrosis factor α ( TNF -α) gene promoter 308 position polymorphisms in predicting acute graft rejection following renal transplantation. Methods In 35 preoperative recipients, TNF-α produced by peripheral blood cells was measured by enzyme-linked immmunosorbent assay, and their TNF- α gene promoter 308 position polymorphisms were determined by FOR restriction fragment length polymorphisms(PCR-RFLP). The assocication between TNF-α gene promoter polymorphisms and production of them was studied. Furthermore, the correlation between their polymorphisms and acute rejection in the first 3 months after renal transplantation was discussed. Results The recipients with A/A or A/G genotype in TNF-α promoter 308 position secreted more cytokine (624.96 ± 177.78) pg/ml and (544.32 ± 13.242)pg/ml than those with G/G(233.16 ± 25.37)pg/ml,P【0.01. When HLA-DR was mismatched, the recipients with high production of TNF - α genotype showed higher incidence

成人再次肝移植研究进展

再次肝移植是肝移植术后移植肝衰竭的唯一治愈性手段。首次肝移植与再次肝移植间隔时间的长短,将直接影响成人再次肝移植的手术适应证、技术难度和治疗转归。既往多项研究认为再次肝移植术后移植肝及受者总体生存率明显低于首次肝移植,但随着器官保存方法、麻醉管理理念、重症监护策略、外科手术技术和新型免疫抑制药等各个领域的全面进步,成人再次肝移植的疗效显著提高。本文就成人再次肝移植手术适应证的变迁、手术时机的选择、长期疗效及其影响因素、手术技术难点、免疫抑制方案的选择以及活体再次肝移植的开展情况进行评述,总结目前成人肝移植取得的成果、面临的挑战及潜在解决方案,以期为提高成人再次肝移植的临床疗效提供参考。

吻合血管游离腓骨移植治疗股骨头坏死

背景:吻合血管游离腓骨移植是治疗股骨头坏死常用的有效保髋治疗手段,但其影响因素仍存在争议。目的:探究吻合血管游离腓骨移植治疗股骨头坏死的临床疗效,及股骨头坏死的病因分类和病变严重程度对其疗效的影响。方法:采集吻合血管游离腓骨移植治疗股骨头坏死患者63例(共73髋)的临床资料及术前、术后髋关节的临床疗效评分。按股骨头坏死的病因分类标准分为激素性、酒精性和特发性3组,参照Ficat分期标准分为FicatⅡ期、FicatⅢ期和FicatⅣ期3组,分析病因分类和病变程度对吻合血管游离腓骨移植治疗股骨头坏死临床疗效的影响。结果与结论:①吻合血管游离腓骨移植治疗股骨头坏死术后各阶段的目测类比评分均较术前明显降低(P<0.001),术后各阶段的Harris评分均较术前明显升高(P<0.001);②在激素性、酒精性和特发性3组中,除激素性组术后2,3年,其余各组术后各时点Harris评分均较术前明显升高(P<0.05);③在FicatⅡ期、FicatⅢ期和FicatⅣ期3组中,FicatⅡ期和FicatⅢ期各组术后Harris评分均较术前明显升高(P<0.05),FicatⅣ期术后Harris评分与术前比较差异无显著性意义(P>0.05);④结果提示,吻合血管游离腓骨移植治疗股骨头坏死临床疗效显著,可以减轻患者髋部疼痛和改善髋关节功能;其疗效可能不受病因的影响,而受病变严重程度的影响。

肺移植术后需要临床干预的气道狭窄患者生存结局的影响因素

目的分析肺移植术后需要临床干预的气道狭窄患者生存结局的影响因素。方法回顾性分析肺移植术后需要临床干预的66例气道狭窄患者的临床资料。采用单因素和多因素Cox回归模型分析所有气道狭窄患者和早期气道狭窄患者生存结局的影响因素,采用Kaplan-Meier法计算总生存率并绘制生存曲线。结果66例气道狭窄患者,中位无气道狭窄时间为72(52,102)d,27%(18/66)发生中心气道狭窄,73%(48/66)发生远端气道狭窄。术后机械通气时间[风险比(HR)1.037,95%可信区间(CI)1.005~1.070,P=0.024]和手术类型(HR 0.400,95%CI 0.177~0.903,P=0.027)均与肺移植术后气道狭窄患者的生存结局存在相关性,术后机械通气时间越长,受者死亡风险越高;接受双肺移植的气道狭窄患者的总生存率优于单肺移植。在亚组分析中,3级原发性移植物失功(PGD)(HR 4.577,95%CI 1.439~14.555,P=0.010)和免疫抑制药(HR 0.079,95%CI0.022~0.287,P<0.001)与肺移植术后早期气道狭窄患者生存结局均存在相关性;无3级PGD的肺移植术后早期气道狭窄患者的总生存率优于有3级PGD的患者,使用他克莫司的肺移植术后早期气道狭窄患者的总生存率优于使用环孢素的患者。结论术后机械通气时间长、单肺移植手术方式、3级PGD和使用环孢素可能影响肺移植术后气道狭窄患者的生存。

劈离式肝移植术后成功妊娠分娩1例并文献复习

目的探讨劈离式肝移植(SLT)术后患者妊娠分娩的临床管理经验。方法收集1例我院器官移植中心收治的SLT术后妊娠并成功分娩患者的临床资料,并复习相关文献。结果患者因“自身免疫性肝炎后肝硬化(失代偿期)”接受同种异体原位SLT,术后出现轻度急性排斥反应,经调整免疫抑制药物治疗后好转。患者术后2年自然妊娠,因既往服用麦考酚钠肠溶片,选择终止妊娠并停用该药。术后3年再次妊娠并出现移植物波动,予调整抗排异药物剂量、保肝对症治疗、先兆早产保胎治疗等处理,最终在肝移植科、产科和新生儿科等相关学科共同指导下,于孕35周剖宫产诞下1名健康女婴。结论SLT受者虽然孕期可能出现移植物功能波动、早产等情况,但在多学科共同合作、科学指导用药及密切随访监测下,亦可以获得满意预后。

2023年中国肝移植临床研究年度盘点

肝移植作为成熟的器官移植手术已成为终末期肝病的最佳治疗手段,提高了患者的生存质量。但目前肝移植依然面临诸多挑战,如排斥反应、感染、胆道并发症、移植物功能恢复延迟、缺血-再灌注损伤、肝细胞癌肝移植术后复发、移植后肾相关疾病、供者短缺等,亟待改善和解决。伴随着我国各位专家学者不断的尝试和经验总结,肝移植相关问题逐年突破。2023年,中国肝移植团队在临床研究领域取得了一系列重大进展,本文就2023年度肝移植临床相关的前沿以及肝移植领域的新技术进展进行综述,总结我国2023年在肝移植领域临床研究取得的成果,以期为促进我国肝移植的进一步发展提供新思路。

Predicting outcomes after kidney transplantation: Can Pareto’s rules help us to do so?

Kidney transplantation is the best option for kidney replacement therapy,even considering that most of the times the grafts do not survive as long as their recipients.In the Khalil et al's experience,published in this issue of the Journal,they analyze their second kidney graft survival and describe those significant predictors of early loss.This editorial comments on the results and put in perspective that most of the times,long-term graft survival could be inadvertently jeopardized if the immunosuppressive therapy is reduced or withdrawn for any reason,and that it could happen frequently if the transplant physician intends to innovate with the clinical care without proper evidence-based data.

间充质干细胞联合免疫抑制剂对肝移植大鼠模型免疫排斥的影响

目的探讨间充质干细胞(MSC)联合免疫抑制剂(IS)对肝移植大鼠模型免疫排斥反应的影响。方法将F344大鼠分成5组:Normal组(不进行任何干预)、PS组(注射等量生理盐水)、MSC组(注射MSC)、IS组(注射IS)、MSC+IS组(注射MSC和IS),每组8只。除Normal组以外,各组均采用Kamada双袖套法不重建肝动脉建立原位肝移植模型。大鼠肝组织进行HE染色、Masson染色并进行纤维化程度统计,免疫组化实验检测T淋巴细胞和NK细胞浸润情况,免疫荧光实验分析巨噬细胞M2极化情况。计量资料多组间比较采用单因素方差分析,进一步两两比较采用LSD-t检验。Kaplan-Meier法绘制生存曲线,生存分析采用Log-rank检验。结果与PS组相比,MSC+IS组生存期显著延长(P<0.01),MSC组、IS组和MSC+IS组的肝组织结构明显改善,纤维化程度显著降低(P值均<0.0001),NK细胞和T淋巴细胞浸润数量显著减少(P值均<0.0001),巨噬细胞M2极化程度显著增加(P值均<0.0001),提示MSC+IS组的疗效显著优于MSC组和IS组。结论MSC联合IS可以改善大鼠肝移植术后肝组织病理,降低炎性细胞浸润,促进巨噬细胞M2极化,起免疫抑制作用。

不同冷冻技术对同种异体血管移植排斥反应的影响

背景:冻存能够较好地保证血管结构的完整性,如何改善移植后排斥反应的问题受到越来越多的关注。目的:综述不同冷冻技术降低同种异体血管移植排斥反应的研究进展,以期为临床研究提供参考。方法:系统检索中英文数据库CNKI、万方和PubMed以及在线网站Baidu和Google Scholar自建库以来发表的降低同种异体血管移植排斥反应的相关文献。中文检索关键词:心血管疾病、内皮细胞、低温冻存、血管移植、免疫原性、排斥反应,同种异体移植和冷冻保护剂;英文检索关键词:cardiovascular disease、endothelial cells、cryopreservation、blood vessel transplantation or vascular graft、Immunogenicity、immune rejection、allograft or allogeneic transplantation or allograft transplantation and cryoprotectant。按照纳入排除标准共选取68篇文献进行综述。结果与结论:①综述发现通过改进现有冷冻技术能够降低同种异体血管移植排斥反应,其中主要涉及冻融方式和冻存保护剂的选择。②现有研究提示冻干法优于低温冻存,但限于条件未能广泛开展,现仍以低温冻存为主,其中玻璃化冻存、缓慢复温和使用不锈钢乃至含银材料效果优于程序式冻存及快速复温。③渗透性和非渗透性冻存保护剂的联合选择,可以在降低其毒性的同时,进一步减少排斥反应的发生。