Barr Virus Infection (barr + virus_infection)

Distribution by Scientific Domains
Distribution within Medical Sciences

Selected Abstracts

B-lymphocyte subpopulations are equally susceptible to Epstein,Barr virus infection, irrespective of immunoglobulin isotype expression

IMMUNOLOGY, Issue 4 2003
Barbro Ehlin-Henriksson
Summary While Epstein,Barr virus (EBV) is known to establish latency in the memory B-cell compartment, there is controversy as to whether the memory or the naïve B cell is the initial target for infection. Here we have explored the infectability of the B-cell subsets contained in peripheral blood and tonsils, as distinguished by their surface expression of the immunoglobulin isotypes that help to define naïve and memory pools. First we show that both CD21 and major histocompatibility complex (MHC) class II molecules , respectively, the major receptor and co-receptor for EBV on B cells , are expressed at similar levels on blood and tonsillar B cells, irrespective of surface immunoglobulin class, indicating that each of the subsets demonstrate an equal potential, at least for infection. Then, following in vitro infection of total tonsillar B cells, we found that the relative frequencies of immunoglobulin (Ig)M-, IgG- and IgA-positive cells containing EBV-encoded Epstein,Barr virus nuclear antigen 5 (EBNA5) protein at 48 hr were similar to those of the starting population. However, IgD expression was uniformly decreased, probably as a consequence of cellular activation. These data indicate that recirculating B cells have both the potential for, and susceptibility to, initial infection by EBV, irrespective of the immunoglobulin isotype expressed. [source]

Cholestatic hepatitis, acute acalculous cholecystitis, and hemolytic anemia: primary Epstein,Barr virus infection under azathioprine

Stefan Hagel MD
First page of article [source]

EBNA1 sequences in Argentinean pediatric acute and latent Epstein,Barr virus infection reflect circulation of novel South American variants,

Mario Alejandro Lorenzetti
Abstract Epstein,Barr virus (EBV) is related to the development of lymphomas and is also the etiological agent for infectious mononucleosis (IM). Sequence variation of the EBNA1 gene, consistently expressed in all EBV-positive cells, has been widely studied. Based on the amino acid at codon 487 five major EBNA1 variants have been described, two closely related prototypic variants (P-ala and P-thr) and three variant sequences (V-leu, V-val, and V-pro). Sub-variants were then further classified based on mutations other than the originally described. While several studies proposed associations with tumors and/or anatomical compartments, others argued in favor of a geographical distribution of these variants. In the present study, EBNA1 variants in 11 pediatric patients with IM and 19 pediatric EBV lymphomas from Argentina were compared as representatives of benign and malignant infection in children, respectively. A 3-month follow-up study of EBNA1 variants in peripheral blood cells and in oral secretions of patients with IM was performed. A new V-ala variant which includes five V-ala sub-variants and three new V-leu sub-variants was described. These data favor the geographical association hypothesis since no evidence for a preferential compartment distribution of EBNA1 variants and sub-variants was found. This is the first study to characterize EBNA1 variants in pediatric patients with infection mononucleosis worldwide. J. Med. Virol. 82:1730,1738, 2010. © 2010 Wiley-Liss, Inc. [source]

Regulatory T cell activity in primary and persistent Epstein,Barr virus infection

P.J. Wingate
Abstract Regulatory T cells (Treg) provide a balance to immune T cell activation thereby protecting the body from pathogen-induced immunopathology. Several persistent viruses induce Treg that subvert protective immune mechanisms and promote viral persistence. Epstein,Barr virus (EBV) generally infects children subclinically and persists thereafter, but primary infection in early adulthood may cause immunopathological damage manifest as infectious mononucleosis. In this study the role of Treg was investigated in acute infectious mononucleosis and healthy EBV seropositive donors. The proportion of CD4+CD25high T cells in blood from infectious mononucleosis patients was significantly lower than in seropositive donors (P,=,0.05). Using the FOXP3 marker for Treg the same frequency and extra-follicular distribution of Treg was noted in infectious mononucleosis and control tonsils. Regulatory cytokines, interleukin (IL)-10 and transforming growth factor (TGF)-,, were significantly raised in infectious mononucleosis compared to seropositive donor plasma (P,=,0.0001, P,=,0.0004 respectively) although levels of IL-10 peaked earlier in infectious mononucleosis than TGF-,. Previous studies identified EBV latent membrane protein (LMP)-1-induced Treg activity [Marshall et al. (2003): J Immunol 170:6183,6189; Marshall et al. (2007): Brit J Haematol 139:81,89], and in this study a significant reduction in interferon-, production was found from infectious mononucleosis but not seropositive donor lymphocytes after stimulation with a recall antigen when LMP-1 peptide PRG was added (P,=,0.03). It is possible that Treg are important in controlling primary EBV infection to a subclinical level in most cases and that infectious mononucleosis represents a failure of this protective mechanism. J. Med. Virol. 81:870,877, 2009. © 2009 Wiley-Liss, Inc. [source]

Impact of primary Epstein,Barr virus infection on timing of transplantation

Françoise Smets
No abstract is available for this article. [source]

Patient Report: Case of acute cerebellar ataxia associated with primary Epstein,Barr virus infection

Tomomi Harai
No abstract is available for this article. [source]

Multiple organ failure and severe bone marrow dysfunction in two 18 year-old Caucasian patients: Epstein,Barr virus and the haemophagocytic syndrome

ANAESTHESIA, Issue 11 2008
P. A. Berry
Summary Haemophagocytic lymphohistiocytosis secondary to viral infection is an unusual but well recognised cause of bone marrow dysfunction and multiple organ failure in young patients. Two 18 year-old patients were admitted to a tertiary liver unit with features of acute liver failure, cardio-respiratory collapse and pancytopenia. Serological tests and bone marrow examination with in-situ hybridisation revealed severe acquired haemophagocytic lymphohistiocytosis secondary to acute Epstein,Barr virus infection. Both patients died despite full supportive therapy; the first due to pulmonary haemorrhage, the second due to acute respiratory distress syndrome refractory to high frequency oscillatory ventilation. The clinical spectrum, diagnostic features and current evidence based recommendations for treatment of this condition are explored. The diagnosis of haemophagocytic lymphohistiocytosis should be considered in young patients with marked bone marrow dysfunction and multiple organ failure. Further research into appropriate therapy for patients with acute severe forms of the disease who require intensive organ support is required. [source]

Epstein,Barr virus infection during pregnancy and the risk of adverse pregnancy outcome

Anne Eskild
Objectives To study the association between Epstein,Barr virus (EBV) antibody status in early pregnancy and pregnancy outcomes including fetal death, length of gestation and fetal weight and length at birth. Design Nested control study. Setting Population based health registers. Population The source population comprised 35,940 pregnant women. Cases were all (280) women with fetal death and a random sample of 940 women with a live born child. Method Information on pregnancy outcome was obtained from the Norwegian Medical Birth Registry. Serum samples from the first trimester were tested for EBV antibodies. In women seronegative for EBV, further serum from late pregnancy was analysed to detect seroconversion. Main outcome measures Vital status, length of gestation, weight and length at birth. Results There was no association between EBV antibody status and fetal death. Women with significant EBV reactivation had a significantly shorter duration of pregnancy, and associated lighter babies, compared with women without significant reactivation (stillborn: 176 vs 197 days, P= 0.16, and live born: 271 vs 279 days, P= 0.03, respectively). Conclusion Significant reactivation of EBV infection during pregnancy may influence pregnancy duration. [source]

Hypersensitivity to mosquito bites in association with chronic Epstein,Barr virus infection and natural killer (NK) leukaemia/lymphoma with expansion of NK cells expressing a low level of CD56

A. Adachi
No abstract is available for this article. [source]

Marked swollen erythema of the face together with sicca syndrome as a sign for chronic active Epstein,Barr virus infection

K.C. Sato-Matsumura
No abstract is available for this article. [source]

Prevalence of SAP gene defects in male patients diagnosed with common variable immunodeficiency

SUMMARY The molecular basis of common variable immunodeficiency (CVID) is undefined, and diagnosis requires exclusion of other diseases including X-linked lymphoproliferative disease (XLP). This rare disorder of immunedysregulation presents typically after Epstein,Barr virus infection and results from defects in the SAP (SLAM associated protein) gene. SAP mutations have been found in a few patients diagnosed previously as CVID, suggesting that XLP may mimic CVID, but no large-scale analysis of CVID patients has been undertaken. We therefore analysed 60 male CVID and hypogammaglobulinaemic patients for abnormalities in SAP protein expression and for mutations in the SAP gene. In this study only one individual, who was found later to have an X-linked family history, was found to have a genomic mutation leading to abnormal SAP cDNA and protein expression. These results demonstrate that SAP defects are rarely observed in CVID patients. We suggest that routine screening of SAP may only be necessary in patients with other suggestive clinical features. [source]

A case of fulminant post-transplant lymphoproliferative disorder and septicemia

Ghazaleh Gouya
Abstract: The fulminant form of post-transplant lymphoproliferative disorder (PTLD) is very uncommon and occurs in approximately 1% of PTLD patients. Approximately 85% of these lesions are of B-cell origin, and most of them are associated with Epstein,Barr virus infection. Fulminant PTLD is frequently associated with a systemic inflammatory response syndrome, and may be difficult to differentiate from septicemia. We describe the case of a 59-yr-old man who suffered from prolonged septicemia in the immediate post-transplant period, and presented again four months after cardiac transplantation with fever, painful liver edge and gastrointestinal bleeding. The diagnosis of fulminant PTLD with advanced multiorgan infiltration by a diffuse large-cell lymphoma of B-cell phenotype was made. During treatment with rituximab, the patient died from Enterococcus faecium septicemia. The sequence of septicemia, PTLD and, finally again, septicemia is an unusual challenge and urges for an aggressive diagnostic approach, where markers like procalcitonin may aid in the discrimination of fulminant PTLD from septicemia. [source]