Sites of Epstein-Barr virus replication in acute and chronic active Epstein-Barr virus infections

We examined Epstein-Barr virus (EBV) in saliva samples and peripheral blood mononuclear cells (PBMC) from 9 patients with acute infectious mononucleosis (IM) and 4 patients with chronic active EBV infection (CEBV). All saliva samples from patients with acute IM were positive for EBV by both Southern blot hybridization assay and the cord transformation assay. In contrast, EBV DNA could not be detected in saliva samples from patients with CEBV. Only one of the saliva samples from 4 patients with CEBV could transform cord blood lymphocytes with extreme difficulty. No saliva samples from patients with CEBV were capable of inducing early antigens in Raji cells. On the other hand, EBV DNA was detected in PBMC from 3 of the 4 patients with CEBV but not in those from patients with acute IM by Southern blot hybridization. Spontaneous lymphoblastoid cell lines could be easily established from PBMC of patients with acute IM but not from PBMC of patients with CEBV, despite several attempts. Viral capsid antigen and early antigens were not observed in cultured cells from patients with CEBV. These results suggest that the main site of EBV replication in CEBV might not be oropharyngeal epithelial cells.     

Limitations of polymerase chain reaction testing for diagnosing acute Epstein-Barr virus infections

Clinicians use molecular tests to detect Herpesviridae from blood without fully appreciating limitations of testing. Studies are needed to enhance our understanding of the impact of Herpesviridae latency on molecular testing. We retrospectively performed quantitative Epstein-Barr virus (EBV) on sera from patients between the ages of 1 and 30 who demonstrated serologic evidence of acute EBV (n = 50) or remote EBV (n = 50) infection. Epstein-Barr virus DNA was detected in 70% of acutely infected and 4% of remotely infected patients. Sera from acutely infected patients had higher EBV copy number than convalescent sera. Our results suggest that serology should be performed as the initial diagnostic test for acute EBV. The role for polymerase chain reaction in immunocompromised patients with impaired antibody responses or as a 2nd-line diagnostic test when serologic results are equivocal deserves further study.     

ME-609: a treatment for recurrent herpes simplex virus infections

Studies in conventional murine models of HSV infection use immunologically naive animals. These models thus mimic primary infections rather than recurrent infections in humans. We have, therefore, used a newly developed mouse model that more closely mimics recurrent HSV infection in humans. In this model, the mice are infected, and zosteriform HSV-1 infection develops in the presence of a primed immune response using adoptive transfer of immunity (ATI) as we have described previously. Using the ATI mouse model, it has been shown that a more beneficial therapy for recurrent mucocutaneous HSV infection could be achieved by controlling both the viral replication and the inflammatory response to the virus. Topical treatment was initiated in this model at the time of first occurrence of symptoms and was given three times daily for 4 days. Topical treatment with ME-609 (which contains 5% acyclovir and 1% hydrocortisone) in the ATI mouse model was substantially more efficacious than 5% Zovirax cream, 1% hydrocortisone or no treatment, respectively. The beneficial properties of ME-609 were also found to be superior to those of Zovirax cream when tested in the standard guinea pig model, representing a primary HSV infection. ME-609 represents a novel treatment principle of recurrent HSV infections and the present paper summarizes the preclinical and early clinical experience of ME-609.     

Real-time Epstein-Barr virus PCR for the diagnosis of primary EBV infections and EBV reactivation.

BACKGROUND: The serological diagnosis of primary Epstein-Barr virus (EBV) infections is often difficult, whereas the relevance of elevated immunoglobulin G (IgG) antibodies against early antigen (EA) for the diagnosis of EBV reactivation has increasingly become a matter of dispute. Recently, EBV PCR has been added as a diagnostic tool. Positive EBV PCR has been demonstrated in the serum of patients with primary EBV infections and EBV reactivation. OBJECTIVES: To compare classical serological diagnosis of primary EBV infection and EBV reactivation with real-time EBV PCR. STUDY DESIGN: Sera from 45 patients were selected with detectable immunoglobulin M (IgM) antibodies against EBV viral capsid antigen (VCA), and 62 sera were selected with a reactivation profile. A real-time EBV PCR was performed with DNA extracted from these sera. RESULTS: Based on serological data, the diagnosis of primary EBV infection was established for 24 of the 45 IgM VCA-positive patients. By performing PCR, seven extra cases of primary infection were diagnosed for which no heterophilic antibodies could be detected. In five cases of primary infection, no EBV DNA could be detected by PCR. Only in two of the 62 sera with a reactivation seroprofile could EBV DNA be detected. CONCLUSIONS: Based on these data, we suggest that for the diagnosis of primary infections, EBV PCR could lead to an increase of >16% in the number of positive diagnoses by confirming a positive IgM VCA in the absence of heterophilic antibodies. Furthermore, EBV PCR is positive in only 3% of sera with elevated antibodies against EA, raising doubt as to the utility of EA titers for diagnosing EBV reactivation.     

EB病毒相关移植后淋巴组织增殖性疾病治疗的研究进展

移植后淋巴增生性疾病(post-transplant lymphoproliferative disorder,PTLD)是实体器官移植和造血干细胞移植术后罕见而致命的并发症。近年来,随着器官移植数量的增加,PTLD发病增加。目前认为PTLD的主要病因是EB(EpsteinBarr)病毒感染。PTLD包含一系列疾病,临床表现不尽相同,一旦确诊,应降低免疫抑制水平,并联合利妥昔单抗、化疗等方案进行治疗。该文旨在总结PTLD治疗方法的进展,为临床上对PTLD患者的管理提供新的思路,从而提高PTLD患者的存活率。     

Epstein-Barr virus infectious mononucleosis

Infectious mononucleosis should be suspected in patients 10 to 30 years of age who present with sore throat and significant fatigue, palatal petechiae, posterior cervical or auricular adenopathy, marked adenopathy, or inguinal adenopathy. An atypical lymphocytosis of at least 20 percent or atypical lymphocytosis of at least 10 percent plus lymphocytosis of at least 50 percent strongly supports the diagnosis, as does a positive heterophile antibody test. False-negative results of heterophile antibody tests are relatively common early in the course of infection. Patients with negative results may have another infection, such as toxoplasmosis, streptococcal infection, cytomegalovirus infection, or another viral infection. Symptomatic treatment, the mainstay of care, includes adequate hydration, analgesics, antipyretics, and adequate rest. Bed rest should not be enforced, and the patient's energy level should guide activity. Corticosteroids, acyclovir, and antihistamines are not recommended for routine treatment of infectious mononucleosis, although corticosteroids may benefit patients with respiratory compromise or severe pharyngeal edema. Patients with infectious mononucleosis should be withdrawn from contact or collision sports for at least four weeks after the onset of symptoms. Fatigue, myalgias, and need for sleep may persist for several months after the acute infection has resolved.     

Epstein-Barr virus and carcinomas

Summary The Epstein-Barr virus, a human B lymphotropic herpes virus, is strongly associated with undifferentiated nasopharyngeal carcinoma, which is endemic in Southern China and North Africa. More recently, an association of the virus with certain other epithelial malignancies has been described, some of which are more common in Western countries. Also, the observation that oral hairy leukoplakia, an acquired immunodeficiency syndrome-related lesion of the tongue, supports Epstein-Barr virus replication in the epithelial cell compartment has further strengthened the notion that Epstein-Barr virus infection of epithelial cells may be an important phenomenon in vivo. The purpose of this article is to review the association of Epstein-Barr virus with nasopharyngeal carcinomas, to examine the evidence suggesting an association of the virus with other epithelial neoplasias and to discuss Epstein-Barr virus infection of non-neoplastic epithelial cells.     

Approaches and strategies for the treatment of influenza virus infections.

Influenza A and B viruses belong to the Orthomyxoviridae family of viruses. These viruses are responsible for severe morbidity and significant excess mortality each year. Infection with influenza viruses usually leads to respiratory involvement and can result in pneumonia and secondary bacterial infections. Vaccine approaches to the prophylaxis of influenza virus infections have been problematic owing to the ability of these viruses to undergo antigenic shift by exchanging genomic segments or by undergoing antigenic drift, consisting of point mutations in the haemagglutinin (HA) and neuraminidase (NA) genes as a result of an error-prone viral polymerase. Historically, antiviral approaches for the therapy of both influenza A and B viruses have been largely unsuccessful until the elucidation of the X-ray crystallographic structure of the viral NA, which has permitted structure-based drug design of inhibitors of this enzyme. In addition, recent advances in the elucidation of the structure and complex function of influenza HA have resulted in the discovery of a number of diverse compounds that target this viral protein. This review article will focus largely on newer antiviral agents including those that inhibit the influenza virus NA and HA. Other novel approaches that have entered clinical trials or been considered for their clinical utility will be mentioned.     

EB病毒感染机制及临床研究进展

EB病毒（EBV）属于疱疹病毒γ亚科,是双链DNA病毒,人群普遍感染。其可逃避机体的免疫攻击,在B淋巴细胞内建立持续终身的潜伏感染。EBV感染可引起机体不同程度的免疫反应,可累及机体几乎所有脏器和组织,引起多种非恶性淋巴增殖性疾病、肿瘤性疾病及自身免疫病等。EBV的实验室检查有助于EBV感染的诊断及感染时相的判别。EBV感染机制复杂,感染后临床疾病谱广,轻重不一,预后千差万别,了解EBV感染机制及其相关疾病的预后情况及预后相关因素,对临床上进行更好的预防及治疗有重大意义。本文就EBV感染相关疾病、临床检测、治疗及预后的研究进展作一综述。     

Molecular diagnosis of Epstein-Barr virus

Molecular techniques have become an important tool in Epstein-Barr virus diagnostics. In recent years novel real-time PCR formats and in situ techniques have been developed that offer increased time efficiency, reduced cross-contamination, high reproducibility, high sensitivity and allow determination of viral loads. In the near future, widespread clinical application of these diagnostic modalities may provide increased knowledge of the pathophysiology of Epstein-Barr virus infection and may optimize treatment or even explore novel Epstein-Barr virus-related diseases. The monitoring of Epstein-Barr virus viral loads in different tissue compartments is currently being effectively used to assess the treatment response or prognosis in patients with oncological diseases or immunosuppression. This may also gain increasing importance in the nononcological environment. However, the general acceptance of molecular techniques will largely depend on improved standardization.     

Nanocrystalline Epstein-Barr virus decoys.

A novel biotechnology is introduced by way of the successful synthesis of nanocrystalline Epstein-Barr virus (EBV) decoys having specific in vivo immunogenic activity. Assembled from ultrafine surface modified tin oxide and purified DNA-free isolated EBV envelope proteins, the decoys consisted of less than 150 nm units whose electrophoretic mobilities were similar to whole EBV; whose outer coats were strongly immunoreactive with murine monoclonal anti-EBV antibodies; and which elicited immunospecific neutralizing anti-EBV antibodies in the rabbit. The development of this carrier technology for vaccine preparations is suggested.     

Epstein-Barr virus and malignant lymphoma

Association between Epstein-Barr virus and malignant lymphomas such as Burkitt's lymphoma, Hodgkin's disease(HD), nasal T/NK cell lymphoma(NTL), immunodefficiency-associated lymphoma, and pyothorax associated lymphoma (PAL) has been suggested. Among these, HD, SNL, PAL are relatively common in Japan. For HD, EBV association was found in the disease peak incidences; those are peak in older adults in Japan, older peak of the bimodal peaks in Western countries, and unimodal peak in the childhood in the developing countries. For NTL, EBV was associated with almost all cases with CD56+ phenotype and cases with polymorphic reticulosis morphology with CD56- phenotype. For PAL, most cases are EBV-associated, about 40% of these show Type B subtype, the ratio of type A EBV to type B EBV in PAL was similar to those in immunodeficiency-associated lymphomas.     

Epstein-Barr virus and rheumatoid arthritis: are rheumatoid arthritis associated nuclear antigen and Epstein-Barr virus nuclear antigen different?

In order to investigate the relationship between antibodies to RANA and other Epstein-Barr virus induced antigens, we have tested 50 sera from subjects without rheumatoid arthritis and with various EBV serology patterns for aRANA, aEA, aVCA, aEBNA. Patients were either suffering from Burkitt's lymphoma, infectious mononucleosis, nasopharyngeal carcinoma, Hodgkin's disease or immunodeficiencies, or were healthy controls. RANA was detected by indirect immunofluorescence on G1 synchronized Raji cells. The correlation was very strong between aEBNA and aRANA (r = 0.86) without any correlation between aRANA and aVCA. These data not only strongly support the opinion that aRANA is frequently found in non-rheumatoid diseases but cast doubt on the distinction between RANA and EBNA.