Limited efficacy of gene transfer in herpes simplex virus-thymidine kinase/ganciclovir gene therapy for brain tumors

OBJECT: Low efficacy of gene transfer, transient gene expression, and toxicity of viral vectors are the major hurdles in successful anticancer gene therapy. The authors conducted in vitro (U87MG cell line) and in vivo (xenograft, tumor-bearing rodent model) studies to address the stability of transduction by using the adenoassociated virus serotype-2 (AAV2)-thymidine kinase (TK) vector over time. METHODS: Standard methods for cell growth and a ganciclovir (GCV) cytotoxicity assay were applied. The AAV2-TK was infused into implanted tumors in athymic rats via convection-enhanced delivery (CED). Thymidine kinase expression was evaluated through immunohistochemical analysis, and the distribution volumes of the transduced tumors were calculated. Twenty-four hours following the viral infusions, animals were treated with GCV (50 mg/kg intraperitoneally every day for 10 days; six rats) or phosphate-buffered saline (six rats). A rapid decrease in TK expression over time was observed both in vitro and in vivo. A large volume of the tumor (up to 39%) was transduced with AAV2-TK following CED. Administration of GCV resulted in limited therapeutic effects (survival of 25.8 compared with 21.3 days). CONCLUSIONS: Rapid elimination of TK expression from dividing tumor cells and focal transduction of the brain tumor were most likely responsible for the limited bystander effect in this approach. Immediate administration of GCV is crucial to assure maximal efficacy in the elimination of cancer cells. In addition, the complete or diffused transduction of a brain tumor with TK may be required for its total eradication.     

Ganciclovir-sensitive acute graft-versus-host disease in mice receiving herpes simplex virus-thymidine kinase-expressing donor T cells in a bone marrow transplantation setting

BACKGROUND: The use of donor T cells expressing the herpes simplex thymidine kinase (HSV-TK) gene followed by ganciclovir (GCV) treatment could allow for specific modulation of the alloreactivity occurring after bone marrow transplantation. We are presently exploring such an approach in a phase I clinical trial. METHODS: To examine the beneficial effect of administrating HSV-TK-expressing donor T lymphocytes +/- GCV treatment on acute graft-versus-host disease (aGVHD) control, irradiated Balb/c or C57BL/6 mice underwent transplantation with allogeneic bone marrow cells in conjunction with CD3+ allogeneic splenocytes from transgenic mice expressing an HSV-TK transgene. GCV treatment was initiated upon the occurrence of severe aGVHD. RESULTS: GCV treatment resulted in a 40-60% long-term survival rate of GVHD-free recipients having received HSV-TK-expressing T cells, whereas only 0-6% of mice survived without GCV treatment. Lethal aGVHD occurred in all the control animals having received non-HSV-TK-expressing T cells, irrespective of GCV treatment. CONCLUSION: Our results demonstrate that the administration of donor HSV-TK-expressing T cells to hematopoietic stem cell graft recipients followed by GCV treatment at the onset of severe aGVHD significantly reduces aGVHD-induced mortality and results in GVHD-free surviving recipients.     

Characterization of human T lymphocytes engineered to express interleukin-15 and herpes simplex virus-thymidine kinase

Introduction

Preclinical studies have demonstrated that tumor-reactive T cells expressing the interleukin (IL)-15 transgene had enhanced activity. Gene therapy strategies using IL-15 should include a safety mechanism in anticipation of possible adverse effects because IL-15 overexpression has been implicated in autoimmune disorders and may be involved in the pathogenesis of some leukemias. We developed a retroviral vector carrying both IL-15 and the herpes simplex virus-thymidine kinase (HSV-TK) suicide gene and characterized its application in the transduction of human T lymphocytes.

Methods

A retroviral vector carrying IL-15 and HSV-TK genes was optimized for the transduction of human T lymphocytes. IL-15 production was measured by enzyme-linked immunosorbent assay. Thymidine incorporation and cell viability assays were used to assess the efficacy of the HSV-TK suicide gene. Genetically modified tumor-infiltrating lymphocytes (TILs) were assayed for survival after withdrawal from exogenous IL-2. The activity and specificity of retrovirally transduced TILs were assessed using tumor coculture assays.

Results

Human T cells transduced with the IL-15 HSV-TK vector exhibited thymidine uptake in the absence of exogenous cytokine support and survived in culture for up to 80 d without IL-2. IL-15 HSV-TK–transduced T cells were efficiently killed by ganciclovir at concentrations as low as 0.1 μM. TILs transduced with the IL-15 HSV-TK vector retained specific recognition of HLA-A2+, MART1+ melanomas, even after withdrawal of IL-2.

Conclusions

Human T lymphocytes genetically modified with the IL-15 HSV-TK retroviral vector retained the ability to recognize tumor antigen while gaining the ability to secrete IL-15 and prolong their own survival. IL-15 HSV-TK–transduced T cells expressed HSV-TK and could be efficiently eliminated by ganciclovir.     

HSV-TK/ACV系统促肾癌细胞株GRC-1细胞凋亡的实验研究

目的：观察HSV－TK／ACV系统对肾癌GRC－1细胞的杀伤作用及旁观者效应。方法将含不同浓度的肾癌GRC－1／TK细胞与肾癌GRC－1细胞混合培养,分为4组,分别含GRC－1／TK细胞0％、25％、50％及100％,分别用无环鸟苷60μg/ml进行处理,观察细胞形态改变、测定活细胞数并行流式细胞术、电子显微镜检查。结果实验组与对照组GRC－1细胞均无明显变化;含25％以上GRC－1／TK细胞可观察到明显的杀伤作用,并有凋亡峰及凋亡小体形成。结论HSV－TK／ACV系统对肾癌GRC－1细胞具有明显的杀伤作用及旁观者效应,机制可与细胞凋亡有关。     

Successful retroviral gene transfer of simian virus 40 T antigen and herpes simplex virus-thymidine kinase into human hepatocytes

Current clinical reports have indicated that hepatocyte transplantation (HTX) could be used in patients with liver failure and in children with liver-based metabolic diseases. One of the major limiting factors of HTX is a serious shortage of donor livers for hepatocyte isolation. To address this issue, we immortalized adult human hepatocytes with a retroviral vector SSR#69 expressing the genes of simian virus 40 large T antigen and herpes simplex virus-thymidine kinase simultaneously. One of the resulting clones, NKNT-3, grew steadily in chemically defined serum-free medium without any obvious crisis and showed the gene expression of differentiated liver functions. Under the administration of 5 microM ganciclovir, NKNT-3 cells stopped proliferation and died in in vitro experiments. We have established a tightly regulated immortal human hepatocyte cell line. The cells could allow the need for immediate availability of consistent and functionally uniform cells in sufficient quantity and adequate quality.     

Effect of gene therapy with the herpes simplex virus-thymidine kinase gene on hepatic metastasis in murine colon cancer

Hepatic metastasis of colon cancer is an important prognostic factor for survival. In this study, we examined the effect of gene therapy using the herpes simplex virus-thymidine kinase (HS-tk) gene with short-course ganciclovir (GCV) treatment for multiple hepatic metastases of murine colon cancer. Colon26 cells transfected with the (HS-tk) gene were found to be sensitive to GCV in a concentration-dependent way. On the other hand, induction of theHS-tk gene in the cells had no influence on cell growth in vitro. However, multiple hepatic metastases of Colon26 cells transfected withHS-tk gene were significantly suppressed by the GCV treatment. These results thus suggest thatHS-tk gene therapy is useful for the treatment of hepatic metastasis in colon cancer.     

单纯疱疹病毒胸苷激酶/丙氧鸟苷自杀基因系统对胆囊癌细胞的体外作用

目的 探讨单纯疱疹病毒胸苷激酶/丙氧鸟苷(HSV-tk/GCV)自杀基因系统对体外胆囊癌细胞的杀伤效果。方法 将含有tk自杀基因的重组逆转录病毒载体PLtkSN经脂质体介导转染胆囊癌细胞,并测定不同浓度的GCV对转基因细胞GBC-SD/tk的生长抑制率;将GBC-SD/tk与未转基因细胞GBC-SD按不同的比例混合,噻唑蓝(MTT)法测定GCV对不同混合比例细胞的杀伤率,观察旁观者效应。结果 GCV对体外GBC-SD/tk细胞有明显的杀伤作用。与对照组比较差异有非常显著性(P<0.01),并呈现剂量依赖性的特点。当GCV浓度为1、10、50、100、500mg/L时,杀伤率依次为6.8％、25.2％、54.5％、66.3％、89.3％;在混合细胞中,当GBC-SD/tk细胞所占比例分别是0、10％、20％、50％、70％、100％时,GCV对混合细胞的杀伤率依次为0、19.7％、40.3％、77.7％、88.0％、93.5％,提示存在旁观者效应。结论 HSV-tk/GCV自杀基因系统有望成为治疗胆囊癌的有效手段之一。     

单纯疱疹病毒胸苷激酶基因导入T细胞克隆治疗溃疡性结肠炎大鼠

目的探讨单纯疱疹病毒胸苷激酶（HSV-TK）基因导人T细胞克隆治疗溃疡性结肠炎（UC）大鼠的作用。方法将HSV-TK基因导人T细胞克隆回输至27只UC大鼠，观察刺激指数（SI）、CD4^＋、CD8^＋及白细胞介素（IL）-13和IL-4水平的变化，并比较治疗前后结肠病变的情况。结果UC大鼠结肠壁病变于tk^＋细胞克隆回输治疗2-3d出现炎性反应吸收改变，7-10d后结肠炎性反应基本消失；回输前SI值为7．39±1．24，回输后为2．67±0．87（P〈0．05），CD4^＋、CD8^＋水平、IL-13和IL-4水平明显下降，差异有统计学意义（P〈0．05）。结论T细胞克隆疫苗诱导和tk基因导入后杀伤效应的双重作用导致结肠自身抗原特异性免疫耐受的最终形成，HSV-TK自杀基因导入T细胞克隆回输方案是UC基因治疗研究和靶点设计的有效手段。     

Rat adenocarcinoma cell line infected with an adenovirus carrying a novel herpes-simplex virus-thymidine kinase suicide gene construct dies by apoptosis upon treatment with ganciclovir

BACKGROUND: Eukaryotic initiation factor 4E (eIF4E) facilitates the translation of mRNAs with long 5' untranslated regions and thus regulates protein synthesis. This protein has been found in elevated quantities in breast, colon, and head and neck cancers. To exploit this dysfunction, the 619 base pair 5' untranslated regions of fibroblast growth factor-2 was spliced upstream of the herpes simplex virus thymidine kinase gene in an adenovirus vector (Ad-HSV-UTK), with the expectation that TK will be expressed in cells that overexpress eIF4E and, thus, render these cells susceptible to ganciclovir. In this study, we investigated the in vitro activity of this suicide gene therapy against the rat Mat BIII breast adenocarcinoma cell line, and assessed whether apoptosis was the responsible mechanism of cell killing. METHODS: Mat BIII cells were infected with Ad-HSV-UTK, and optimal multiplicity of infection was determined using green fluorescent protein tagged adenovirus. Western blot analysis was used to detect eIF4E and TK expression. Cell viability was assessed by the MTT assay. Induction of apoptosis was determined using annexin V-FITC and propidium iodine detection kit and a terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling in situ cell death detection kit. RESULTS: Western Blot analysis confirmed successful infection of the cell line. Marked cytotoxicity was noted by the MTT assay in the infected group with a 100-fold less concentration of ganciclovir compared with the control groups. Annexin V-FITC/propidium iodide revealed apoptosis in infected cells following treatment with ganciclovir. CONCLUSION: Suicide gene therapy targeting the overexpression of eIF4E induces apoptosis and cell death in rat Mat BIII mammary adenocarcinoma cells.     

胸苷激酶基因系统联合大蒜素诱导膀胱癌细胞凋亡的研究

目的　探讨单纯疱疹病毒胸苷激酶 (HSV TK) /更昔洛韦 (GCV)系统联合大蒜素对膀胱癌细胞的协同杀伤效应及对细胞凋亡的影响。方法　通过脂质体将胸苷激酶 (TK)基因转入膀胱癌BIU87细胞构建BIU87TK细胞,观察GCV(1mg/L)、大蒜素(5mg/L)及GCV+大蒜素(浓度同前)共同作用对BIU87TK细胞形态学、细胞凋亡率及细胞周期变化的影响,检测bcl 2、bax、半胱天冬蛋白酶(caspase 3)表达变化及caspase 3活性变化。结果　药物作用 72h,GCV+大蒜素对BIU87TK细胞的抑制率为 72 50%,高于GCV作用后的 35 00%和大蒜素作用后的 37 00%,二者可发挥协同抑瘤作用; (F=6 46,P<0 05)。GCV+大蒜素联合作用前期凋亡率高于单独作用细胞,细胞周期阻滞在S和G2 期,与单独作用比较阻滞时效提前;二者可抑制bcl 2表达并可促进caspase 3表达及活化。结论　HSV TK/GCV系统联合大蒜素可通过共同诱导凋亡发挥协同作用,抑制膀胱癌细胞生长。细胞周期阻滞,相关凋亡基因表达及活性的变化可能发挥了重要的作用。     

Gene therapy of metastatic pancreas cancer with intraperitoneal injections of concentrated retroviral herpes simplex thymidine kinase vector supernatant and ganciclovir.

OBJECTIVE: The objective of this study was to determine the efficacy of intraperitoneal (IP) injections of a new concentrated herpes simplex thymidine kinase (HS-tk) retroviral vector and ganciclovir (GCV) for peritoneal metastases from pancreas cancer. SUMMARY BACKGROUND DATA: Metastatic pancreas cancer is fatal. Gene therapy may provide a novel approach for this disease. Gene therapy with adeno- or retroviral-mediated transfer of the HS-tk gene into tumor cells renders the cells susceptible to GCV. Intratumoral or intracavity injections of retroviral vectors have been ineffective in previous studies. METHODS: Pancreatic cancer B x PC3 cells (3 x 10(7)) were injected into the tail of pancreas in nude mice. Mice received IP injections of a concentrated HS-tk vector (5 x 10(7)) cfu/mliters) or a control vector (G1Na) without the tk gene for 10 days and GCV (100 mg/kg) for 14 days. To determine whether the vector would survive in the milieu of the peritoneal cavity, the authors examined the effects of ascitic fluid on the vector. Pancreas cancer cells were transduced in vitro with HS-tk vector in presence of media or ascitic fluid and treated with GCV. RESULTS: Highly significant reductions in the mass of metastatic peritoneal tumor deposits were found in HS-tk-treated group (124 +/- 27 mg; n = 11) compared with G1Na vector controls (910 +/- 168 mg; n = 8; p < 0.0001). Results of polymerase chain reaction analysis demonstrated integration of the vector in the tumors, and on immunohistochemistry, expression of the TK protein was seen in the number of surviving colonies (representing nontransduced cells) were similar in both groups, suggesting that the vector effectively transduced tumor cells bathed in the ascitic fluid. CONCLUSIONS: Results demonstrate that IP administration of concentrated retroviral HS-tk vectors is effective treatment for pancreas cancer metastatic to the peritoneal cavity; furthermore, the vector is active in the presence of ascitic fluid. Intraperitoneal retroviral HS-tk may provide a novel approach to treatment of metastatic pancreas cancer.     

单纯疱疹病毒胸苷激酶/更昔洛韦系统联合化疗药物治疗前列腺癌

目的探讨单纯疱疹病毒胸苷激酶／更昔洛韦（HSV-TK／GCv）系统联合几种临床常用的化疗药物对激素非依赖性人前列腺癌（HRPC）细胞PC-3m的杀伤效应。方法将HSV-TK基因导入PC-3m细胞，采用活细胞拒染法、四甲基偶氮唑盐酶反应比色法（MTT法）检测单独给予GCV（10μmol／L）和顺铂（CDDP，10μmol／L）、足叶乙甙（VP-16，10μmol／L）、长春新碱（VCR，135nmol／L）、氨甲喋呤（MTX，5nmol／L）、5-氟尿嘧啶（5-Fu，1μmol／L）及苏拉明（100μmol／L）等物质，以及GCV联合上述药物对PC-3m细胞的体外杀伤效应，并用流式细胞术（FCM）检测GCV联合5-Fu或苏拉明后细胞坏死和凋亡状况。结果HSV-TK／GCV联合VP-16、VCR、5-Fu和苏拉明后杀伤PC-3m细胞的效应增强，联合CDDP后杀伤效应降低，联合MTX后则杀伤效应无明显改变。FCM检测显示，GCV联合5-Fu和苏拉明后72h出现较大比例的细胞凋亡和细胞坏死。细胞凋亡比例分别为36．38％和35．51％，细胞坏死比例分别为33．05％和28．87％。结论HSV-TK／GCv系统联合某些化疗药物后可对前列腺癌（PCa）细胞发挥协同的杀伤效应。     

Treatment of progressive or recurrent pediatric malignant supratentorial brain tumors with herpes simplex virus thymidine kinase gene vector-producer cells followed by intravenous ganciclovir administration

OBJECT: The outcome for children with recurrent malignant brain tumors is poor. The majority of patients die of progressive disease within months of relapse, and other therapeutic options are needed. The goal of this Phase I study was to evaluate the safety of in vivo suicide gene therapy in 12 children with recurrent, malignant, supratentorial brain tumors. METHODS: After optimal repeated tumor resection, multiple injections of murine vector-producing cells shedding murine replication-defective retroviral vectors coding the herpes simplex virus thymidine kinase type 1 (HSV-Tk1) gene were made into the rim of the resection cavity. Fourteen days after the vector-producing cells were injected, ganciclovir was administered for 14 days. The retroviral vector that was used only integrated and expressed HSV-Tk1 in proliferating cells, which are killed after a series of metabolic events lead to cell death. The median age of the patients was 11 years (range 2-15 years). Treated brain tumors included seven malignant gliomas, two ependyminomas, and three primitive neuroectodermal tumors. The patients were treated with one of three escalating dose concentrations of vector-producer cells. Four transient central nervous system adverse effects were considered possibly related to the vector-producing cells. In no child did permanent neurological worsening or ventricular irritation develop, and tests for replication-competent retroviruses yielded negative findings. CONCLUSIONS: This Phase I study demonstrates that in vivo gene therapy in which a replication-defective retroviral vector in murine vector-producing cells is delivered by brain injections can be performed with satisfactory safety in a select group of children with localized supratentorial brain tumors.     

腺病毒介导HSV-TK/CD基因对胆管癌体内体外的杀伤作用

目的　研究HSV TK /CD融合基因对胆管癌的杀伤作用。方法　腺病毒介导HSV TK /CD融合基因体外转染胆管癌细胞QBC93 9,与单自杀基因对照 ,四甲基偶氮唑蓝 (MTT )比色法测定肿瘤细胞生长抑制率 ,旁观者效应 ;构建胆管癌裸鼠模型 ,瘤内注射重组腺病毒 ,观察肿瘤生长情况。结果　与单一自杀基因转染组对照 ,双基因组表现出更强的抗肿瘤作用。当给予相同浓度的前体药物时 ,融合基因组 ,CD组和TK组的肿瘤细胞存活率分别为 3 .1%、3 2 .1%、5 5 .2 %。体内实验显示 ,融合基因组的肿瘤生长受到明显抑制 ,抑制率达 70 .7%。单自杀基因TK、CD组则分别为 41.2 %和 5 5 .7% ,差异有统计学意义 (P <0 .0 5 )。组织学检查可见实验组肿瘤发生明显坏死 ,这种现象在融合基因治疗组尤为明显。结论　与单自杀基因相比 ,HSV TK/CD融合基因在体内和体外都具有更强的抗肿瘤活性。     

腺病毒介导的胸苷激酶基因治疗肝癌的研究进展

肝癌是我国常见的恶性肿瘤,针对肝癌的传统治疗方法疗效欠佳、患者预后较差.近10余年来,随着分子生物学技术的发展,肝癌的基因治疗成为该领域新的研究方向和热点,其中以腺病毒为载体的单纯疱疹病毒胸苷激酶自杀基因系统（ADV-tk）对肝癌的治疗研究开展得最早也最为广泛.其原理是把单纯疱疹病毒胸苷激酶基因通过腺病毒导入细胞内,利用其产生的酶将无毒的药物前体更昔洛韦（GCV）转变成细胞毒性产物,从而杀死肝癌细胞.多项动物实验和临床研究结果表明：ADV-tk/GCV系统是治疗肝癌的有效方法.本文总结近年来ADV-tk/GCV系统在肝癌治疗中取得的研究进展,分别从载体的发展过程、基因的作用机制、导入方式、增强杀伤效力、降低肝毒性以及相关动物模型的改进等几个方面进行综述.     

Prophylaxis of CMV disease by ganciclovir (DHPG) in seronegative recipients of renal allograft from seropositive donors

In an open-label randomized study of prophylactic treatment by ganciclovir, 23 seronegative recipients of kidney allograft from seropositive donors were randomized to receive from day 14 to day 28 after transplantation either no treatment (n = 11) or ganciclovir, 5 mg/kg twice daily (n = 12). Both groups were similar in age, immunosuppressive therapy, number of acute rejections and in steroid bolus. Seroconversion occurred in ten patients of the control group (91%) and in ten of the ganciclovir group (84%). CMV disease occurred in ten patients of the control group (91%) and in eight patients of the ganciclovir group (66%), three of whom had asymptomatic viraemia. The delay between transplantation and onset of CMV disease was significantly increased by ganciclovir prophylaxis (78.5 ± 7.7 vs 46.5 ± 7.5 days, P < 0.05). We conclude that in renal transplant recipients at risk of CMV disease, ganciclovir prophylaxis delays the onset of the disease and seems to decrease its incidence and its severity.     

硼替佐米对小鼠急性移植物抗宿主病的抑制作用

目的 探讨硼替佐米对小鼠急性移植物抗宿主病(aGVHD)的抑制作用及其可能机制.方法 以C57BL/6小鼠为供鼠,获取骨髓细胞及脾细胞.以Balb/c小鼠为受鼠,共分为5组:空白对照组(n=17)小鼠不予任何处理;单纯照射组(n=17)小鼠仅接受7.0 Gy X射线全身照射(TBI);药物对照组(n=17)小鼠也接受TBI,并且由尾静脉注射硼替佐米;aGVHD组(n=8)小鼠TBI后注射供鼠骨髓细胞及脾细胞;实验组(n=8)小鼠TBI后输注供鼠骨髓细胞及脾细胞,并予以硼替佐米.观察各组小鼠aGVHD的发生情况、存活时间及嵌合状态,蛋白印迹法测定空白对照组、单纯照射组和药物对照组小鼠肝脏及小肠组织细胞核中核因子κB(NF-κB)p65的表达.结果 aGVHD组和实验组的临床aGVHD评分分别为7.37±0.32和5.85±0.40,实验组明显低于aGVHD组(P＜0.05).aGVHD组受鼠肝脏、小肠及皮肤组织为Thomas GVHD病理分级Ⅲ～Ⅳ级改变.实验组受鼠肝脏、小肠及皮肤组织为Ⅰ～Ⅲ级GVHD改变,较aGVHD组有所减轻.实验组存活时间长于aGVHD组(P＜0.05).aGVHD组和实验组小鼠移植后12 d时外周血细胞中H-2Kb分子阳性细胞的百分率均＞90%.药物对照组肝脏及小肠组织细胞核内NF-κB p65表达均高于单纯照射组(P＜0.05).结论 硼替佐米可能通过在一定程度上抑制照射预处理损伤所致肝脏及小肠组织中NF-κB的激活起到减轻aGVHD的作用.

Abstract：

Objective To observe the effect of bortezomib on acute graft-versus-host disease (aGVHD) in an aGVHD model of mice and investigate the related mechanism. Methods Male C57BL/6( H-2Kb)mice were used as donors and female Balb/c (H-2Kd) mice used as recipients. Balb/c mice received total body irradiation (TBI) by 7.0 Gy X-radiation, and randomly divided into five groups. normal (group A), TBI (group B), TBI + bortezomib (group C), TBI + bone marrow cells (BMC) + spleen cells (SC) (group D) and TBI + bortezomib + BMC + SC (group E). The physical signs and the pathological damage of aGVHD, mean survival time, and chimerism were observed in recipients. The NF-κB p65 levels in nuclei of the liver and small intestine tissues of groups A,B and C were analyzed by Western blot. Results ( 1 ) The clinical aGVHD score in group D was (7.37±0. 32), significantly higher than in group E (5.85 ± 0.40) (P＜0. 05). Histopathology of the gut, liver and skin illuminated that the Ⅲ-Ⅳ degree GVHD occurred in group D. The occurrence of aGVHD in group E was later than in group D. The symptoms and the pathological damage of aGVHD in group E were milder than in group D. The average survival time in group E was significantly longer than that in group D (P＜0.05). The percentage of donor-derived cells in recipient mice was above 90% at day 12 after transplantation; (2) NF-κB p65 levels in nuclei of the liver and small intestine tissues in group B was significantly higher than in group C on the day 1,3 and 5 (P＜0. 05). Conclusion Bortezomib can inhibit the activation and expression of NF-κB,which may be the underlying mechanism for it to relieve aGVHD.     

Prevention of lethal graft-versus-host disease by monoclonal antibody treatment in vivo

Graft-versus-host disease (GVHD) is a major complication of allogeneic bone marrow transplantation (BMT). The disease is caused by mature T cells in the graft that recognize foreign antigens of the host and subsequently elicit an immune response to host tissues [1]. Although T-cell depletion of the graft strongly reduced the incidence and severity of GVHD, the overall survival of allogeneic BMT did not increase because of the increased rate of graft rejection and leukemic relapses [2]. New prophylactic and therapeutic approaches have to be developed to improve the outcome of allogeneic BMT. T-cell-specific monoclonal antibodies (mAb) administered in vivo to the allograft recipients seem to be promising in the prevention and treatment of lethal GVHD [3–5]. In this study we especially addressed the effect of in vivo treatment of recipients with anti-T-cell subset mAb in a murine model for acute GVHD. We also determined the long-term effects.