Detection of the Epstein-Barr virus in primary gastric lymphoma by in situ hybridization

The Epstein-Barr virus (EBV) has been shown to be associated with numerous human malignancies including Burktt's lymphoma and nasopharyngeal lymphoepithelioma. In addition, some typical gastric adenocarcinomas were also recently reported to demonstrate EBV relevance. The present study was designed to detect EBV in primary gastric lymphoma, using the in situ hybridization (ISH) method, in which oligo-nucleotide probes for the EBERl RNA and the EBV DNA W region have been used. Of the 49 cases of primary gastric lymphoma studied, which all showed B cell immunopheno-type, EBER1 sequences could only be found in four cases, including two low-grade cases and two high-grade cases of histological subtypes while the number of positive cells was less than 50% of the tumor cells. In one case of low-grade mucosa associated lymphoid tissue (MALT) lymphoma, the EBER1 -positive neoplastic cells were found in the regional lymph node, but the primary site of the stomach showed no positive signals. The EBV presence was further confirmed by the EBV DNA ISH. Using the ISH method, rare or occasional positive lymphoid cells (probably non-tumorous bystander cells) could be detected in 10 other cases including all histological subtypes. The present study shows that only a small proportion of primary gastric lymphoma is associated with EBV, and such positive cases could be found in both high- and low-grade histological subtypes. It is also suggested that the EBV presence in the neoplastic cells of some cases of primary gastric lymphoma is most likely a secondary phenomenon.     

EBV感染患儿临床特征及血清免疫因子水平

目的分析124例巴尔病毒(EBV)感染患儿的临床特征和血清免疫因子水平。方法选择2016年12月-2019年12月于海南医学院第一附属医院确诊的124例EBV感染患儿为研究组,根据临床表现分为传染性单核细胞增多症(IM)组43例和单纯性EBV组81例,选择同期健康体检儿童62名为对照组。记录所有患儿入组时的年龄、性别、临床症状;荧光定量PCR反应检测外周血淋巴细胞中EBV DNA载量;检测血清白细胞介素-6(IL-6)、IL-2和肿瘤坏死因子-α(TNF-α)水平,流式细胞仪分析外周血T淋巴细胞水平;Pearson相关性分析外周血T淋巴细胞亚群与EBV DNA载量之间的相关性。结果 IM组患儿的年龄为(5.13±1.56)岁,大于单纯性EBV组(P<0.05),出现发热、咽峡炎、淋巴结肿大、脾肿大、肝肿大、眼睑水肿、鼻塞、打鼾的比例为88.37%、93.02%、93.02%、48.84%、60.47%、32.56%、55.81%和46.51%,高于单纯性EBV组(P<0.05);IM组患儿的血CD3+T、CD8+T细胞、IL-6、TNF-α为分别为(73.25±7.16)%、(40.19±4.21)%、(33.68±5.71)ng/L、(72.52±11.26)ng/L高于对照组,而CD4+T、CD4+/CD8+T细胞、IL-2分别为(34.86±3.75)%、(0.89±0.15)、(10.43±3.38)ng/L则均低于对照组(P<0.05);外周血CD3+T和CD8+T细胞水平均与病毒载量呈正相关(r=0.314,0.447,P<0.05),CD4+T和CD4+/CD8+T细胞水平与病毒载量呈负相关(r=-0.425,-0.376,P<0.05)。结论 EBV感染患儿的临床症状和细胞免疫功能与病毒载量有关,有望应用于临床评估EBV感染的病情发展。     

Association of antiviral prophylaxis and rituximab use with posttransplant lymphoproliferative disorders (PTLDs): A nationwide cohort study

Posttransplant lymphoproliferative disorder (PTLD) is a serious complication of solid organ transplantation (SOT). Most PTLD cases are associated with Epstein–Barr virus (EBV) infection. The role of antiviral prophylaxis or rituximab therapy for prevention of PTLD in SOT recipients is controversial. In a nationwide cohort, we assessed the incidence, presentation, and outcome of histologically proven PTLD. We included 4765 patients with a follow-up duration of 23 807 person-years (py). Fifty-seven PTLD cases were identified; 39 (68%) were EBV positive (EBV+ PTLD). Incidence rates for EBV+ PTLD at 1, 2, and 3 years posttransplant were 3.51, 2.24, and 1.75/1000 py and 0.44, 0.25, and 0.29/1000 py for EBV− PTLD. We did not find an effect of antiviral prophylaxis on early and late EBV+ PTLD occurrence (early EBV+ PTLD: SHR 0.535 [95% CI 0.199–1.436], p = .264; late EBV+ PTLD: SHR 2.213, [95% CI 0.751–6.521], p = .150). However, none of the patients (0/191) who received a rituximab-containing induction treatment experienced PTLD, but 57 of 4574 patients without rituximab induction developed PTLD. In an adjusted restricted mean survival time model, PTLD-free survival was significantly longer (0.104 years [95% CI 0.077–0.131]) in patients receiving rituximab as induction treatment. This study provides novel data on the association of rituximab induction and reduced risk for PTLD.     

Distinct immunopathological mechanisms of EBV-positive and EBV-negative posttransplant lymphoproliferative disorders

EBV-positive and EBV-negative posttransplant lymphoproliferative disorders (PTLDs) arise in different immunovirological contexts and might have distinct pathophysiologies. To examine this hypothesis, we conducted a multicentric prospective study with 56 EBV-positive and 39 EBV-negative PTLD patients of the K-VIROGREF cohort, recruited at PTLD diagnosis and before treatment (2013–2019), and compared them to PTLD-free Transplant Controls (TC, n = 21). We measured absolute lymphocyte counts (n = 108), analyzed NK- and T cell phenotypes (n = 49 and 94), and performed EBV-specific functional assays (n = 16 and 42) by multiparameter flow cytometry and ELISpot-IFNγ assays (n = 50). EBV-negative PTLD patients, NK cells overexpressed Tim-3; the 2-year progression-free survival (PFS) was poorer in patients with a CD4 lymphopenia (CD4⁺<300 cells/mm³, p <  .001). EBV-positive PTLD patients presented a profound NK-cell lymphopenia (median = 60 cells/mm³) and a high proportion of NK cells expressing PD-1 (vs. TC, p = .029) and apoptosis markers (vs. TC, p < .001). EBV-specific T cells of EBV-positive PTLD patients circulated in low proportions, showed immune exhaustion (p = .013 vs. TC) and poorly recognized the N-terminal portion of EBNA-3A viral protein. Altogether, this broad comparison of EBV-positive and EBV-negative PTLDs highlight distinct patterns of immunopathological mechanisms between these two diseases and provide new clues for immunotherapeutic strategies and PTLD prognosis.     

EB病毒和ConA诱导抑制性T细胞对EB病毒感染B细胞作用探讨

本文探讨了用灭活的EB病毒(EBV)和ConA诱导产生的抑制性T细胞(Ts),对EBV感染自身B细胞的影响,结果表明,EBV抗原诱导产生的抑制性T细胞(Ts)能使EBV感染B细胞中的EBNA阳性细胞数,~3H-TdR掺入量和IgA、IgG及IgM分泌量减少;而ConA诱导产生的Ts则使EBNA阳性细胞数和~3H-TdR掺入量增加,但三种Ig含量无明显变化(P>0.05)。结果提示前者对EBV感染B细胞的激活,增殖和分化均有明显抑制作用,而后者的作用则相反,具有明显促进EBV感染B细胞的作用。     

EB病毒LMP1在鼻咽癌细胞中通过IκBα的降解活化NF-κB

目的　阐明鼻咽癌细胞中EB病毒编码的潜伏膜蛋白 1(LMP1)活化核转录因子NF κB的机制。方法　利用强力霉素Dox诱导表达LMP1的鼻咽癌细胞株Tet on LMP1 HNE2为实验模型 ,首先应用免疫印迹方法测定Dox诱导后不同时相LMP1的表达动力学以及IκBs蛋白量及功能的改变。进而用间接免疫荧光法检测NF κB的亚细胞定位。最后采用瞬间共转染及报道基因活性分析分析NF κB的活性。结果　在鼻咽癌细胞Tet on LMP1 HNE2中 ,Dox处理 15分钟后LMP1的表达迅速升高并维持与较高水平直至 12 0分钟。LMP1的诱导性表达导致IκBα的磷酸化并降解 ,但IκBα蛋白总量无改变。继IκBα的磷酸化并降解 ,NF κB(P6 5 )自胞浆易位至胞核且活性升高。IκBα的显性负性突变子抑制NF κB(P6 5 )的核易位及报道活性。LMP1的诱导性表达并未引起IκBβ蛋白水平变化。结论　在鼻咽癌细胞Tet on LMP1 HNE2中 ,EB病毒LMP1通过IκBα的磷酸化并降解激活核转录因子NF κB的活性 ,并且 ,LMP1诱导的NF κB活性能被IκBα的显性负性突变子完全抑制。IκBβ在此信号传导途径中无改变。LMP1表达前后IκBα蛋白总量维持恒定可能是由于NF κB的活化迅速启动了IκBα的重头合成这一自身调节环路所致。     

Pediatric intestinal transplantation

Advancements in donor management, organ preservation and operative techniques, as well as immunosuppressive therapies, have provided children with intestinal failure and its complications a chance not only for enteral autonomy but also long-term survival through intestinal transplantation (ITx). First described in the 1960’s, experience has grown in managing these complex patients both pre- and post-transplant. The goals of this review are to provide a brief history of intestinal transplantation and intestinal rehabilitation in pediatric patients, followed by focused discussions of the indications for ITx, induction and maintenance immunosuppression therapies, common post-operative complications, and outcomes/quality of life post-transplant.     

EGCG干预LMP1激活的AP-1信号转导通路

目的　探讨EGCG对鼻咽癌细胞激活蛋白 1(AP 1)信号转导通路的干预作用 ,阐明在鼻咽癌细胞中茶多酚干预EB病毒潜伏膜蛋白 1(LMP1)活化的AP 1信号转导通路中靶分子的机制。方法　采用EB病毒阴性及阳性的鼻咽癌细胞系CNE1和CNE1 LMP1细胞。利用四甲基偶氮唑蓝(MTT)法观察EGCG对CNE1和CNE1 LMP1细胞的生存率的影响。采用瞬间转染及报道基因法观察EGCG对AP 1活性的作用。利用间接免疫荧光法观察EGCG对JNK核移位的影响 ,再分别提取CNE1和CNE1 LMP1的胞浆及胞核蛋白 ,Westernblot分析EGCG抑制JNK的核移位后 ,胞浆及胞核蛋白中JNK的变化。采用Westernblot分析EGCG对c Jun的磷酸化水平的影响。采用瞬间转染及报道基因法观察EGCG对cyclinD1启动子活性的影响 ,并用Westernblot分析EGCG对cyclinD1蛋白表达的作用。结果　EGCG对鼻咽癌细胞的抑制作用有剂量依赖性 ,并可抑制AP 1的活性。EGCG能抑制JNK的核移位 ,并抑制c Jun的磷酸化。EGCG对AP 1信号通路下游的靶基因cyclinD1的启动子活性及其蛋白表达都有抑制作用。结论　EGCG对信号转导通路上的AP 1、JNK、c Jun、cyclinD1多个靶点分子具有干预作用。LMP1是EB病毒这种编码的蛋白 ,因此 ,EGCG抑制与病毒相联系的信号转导通路 ,可能是EGCG抑制与病毒相关的肿瘤的分子机