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11.
We describe an experience of a specific immune transfer treatment in a patient with chronic active EBV infection. The patient had low anti-EBV T cell-mediated cytotoxic activity in his peripheral blood mononuclear cells (PBMC), which may have been the primary cause of the disease. An EBV-specific cytotoxic T lymphocyte (CTL) line was established from PBMC obtained from the patient’s sister whose human leucocyte antigens (HLA) are identical to patient's. The patient received three courses of intravenously administered CTL at 3-week intervals. The number of the cells was increased with each course of treatment. After infusion of the T cell line, anti-EBV CTL activity was detected in the patient's PBMC. CTL activity increased markedly after the second course of immune transfer therapy. The amount of EBV DNA in the patient's plasma showed transient but repeated decreases. Serum levels of tumour necrosis factor-alpha (TNF-α), which had elevated before treatment, began to decrease after initiation of treatment. No adverse effects were directly associated with CTL infusions. Despite having previously received a pneumococcal vaccine and prophylactic antibodies, the patient died of infection caused by Streptococcus pneumoniae bacteraemia 27 days after the third infusion. Although the long-term efficacy and safety of this therapy remains to be established, our findings suggest that adoptive transfer of CTL specific for EBV obtained from an HLA-matched donor might be a promising treatment for patients with chronic active EBV infection.  相似文献   
12.
We report on a case of a 40-year-old male patient who underwent a gastrectomy because of a biopsy-proven large B-cell lymphoma of the stomach. On surgery, a nodule in the spleen also was noted. Grossly and microscopically, the two lesions were different: the tumor of the stomach appeared white-gray on the cut surface and was a centroblastic variant of diffuse large B-cell lymphoma. Histologically, one perigastric lymph node was involved. Grossly, the splenic nodule was gray-yellow and had a histological appearance of an inflammatory myofibroblastic tumor (IMT). The association between malignant tumor and IMT is rare. In such an association, the latter lesion most often has been reported in the spleen. As EBV may be involved in the genesis of both lymphoma and IMT, we tested both lesions for its presence using in situ hybridization, but the tests were negative. It remains to be verified whether the association between lymphoma and IMT is more than fortuitous.  相似文献   
13.
14.
A salt-dependent DNA polymerase activity was demonstrated in the culture of an EBV-producing, lymphoblastoid cell line (NPC-204 cells) treated with 5-iodo-2'-deoxyuridine (IUdR). There was a high frequency of levels of antibody to this enzyme in sera of patients with nasopharyngeal carcinoma (NPC). In contrast, sera from healthy subjects had little or no neutralizing activity. The high antibody level appeared as early as stage 1 of the disease in many NPC patients. The levels of the antibody increased with the progression of the disease and declined in treated patients. The results strongly suggest that tests measuring serum antibody against EBV DNA polymerase activity can be used for early diagnosis and prognosis of NPC.  相似文献   
15.
We examined regulation of Epstein-Barr virus-induced plaque-forming cell generation in peripheral blood mononuclear cells from several autoimmune and seronegative diseases and correlated these results with Epstein-Barr virus-induced proliferation. We confirmed the defective regulation of Epstein-Barr virus-induced plaque-forming cells in peripheral blood mononuclear cells of patients with rheumatoid arthritis and scleroderma. Peripheral blood mononuclear cells from patients with seronegative arthropathies and chronic infective inflammation (cystic fibrosis) had normal regulation of Epstein-Barr virus-induced plaque-forming cells. Peripheral blood mononuclear cells from rheumatoid arthritis had excessive plaque-forming cell generation in the face of a normally regulated decrease in Epstein-Barr virus-induced proliferation. In contrast, peripheral blood mononuclear cells from scleroderma had defective suppression of both Epstein-Barr virus-induced proliferation and plaque-forming cell generation. Thus, impaired regulation of Epstein-Barr virus-induced plaque-forming cell generation is a common feature of autoimmune disease and demonstrates some specificity for these disorders.  相似文献   
16.
Epstein–Barr virus (EBV) reactivation is a very common and potentially lethal complication of renal transplantation. However, its risk factors and effects on transplant outcome are not well known. Here, we have analysed a large, multi-centre cohort (N = 512) in which 18.4% of the patients experienced EBV reactivation during the first post-transplant year. The patients were characterized pre-transplant and two weeks post-transplant by a multi-level biomarker panel. EBV reactivation was episodic for most patients, only 12 patients showed prolonged viraemia for over four months. Pre-transplant EBV shedding and male sex were associated with significantly increased incidence of post-transplant EBV reactivation. Importantly, we also identified a significant association of post-transplant EBV with acute rejection and with decreased haemoglobin levels. No further severe complications associated with EBV, either episodic or chronic, could be detected. Our data suggest that despite relatively frequent EBV reactivation, it had no association with serious complications during the first post-transplantation year. EBV shedding prior to transplantation could be employed as biomarkers for personalized immunosuppressive therapy. In summary, our results support the employed immunosuppressive regimes as relatively safe with regard to EBV. However, long-term studies are paramount to support these conclusions.  相似文献   
17.
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.  相似文献   
18.
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.  相似文献   
19.
用间接免疫荧光法测定Raji细胞和B95-8细胞EB病毒抗原的表达。结果显示无细胞毒浓度的茶多酚与亚硒酸钠联合对Raji细胞EBV-EA表达有显著的抑制作用,优于单纯茶多酚或亚硒酸钠的抑制作用。两药显示相互协同增效的作用 。抑制率与药物浓度相关;单纯茶多酚对B95-8细胞EBV-VCA表达无抵制作用,但茶多酚能增强亚硒酸钠对B95-8细胞EBV-VCA表达的抵制作用,抑制率随药物浓度的升高而升高。  相似文献   
20.
Epstein–Barr virus–associated smooth‐muscle tumors (EBV‐SMTs) are unique and rare neoplasms described in immunocompromised patients. The case describes a nine‐year‐old female with a history of acute lymphoblastic leukemia with relapse and subsequent allogeneic bone marrow transplantation who presented with multiple EBV‐SMTs of the liver. EBV utilizes the mammalian target of rapamycin (mTOR) pathway for tumor growth, and sirolimus, a mTOR inhibitor, has shown to result in a short‐term response. We now report an extended treatment response with sirolimus in a pediatric patient with an EBV‐SMT.  相似文献   
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