Role of the capsid protein VP4 in the plasma-dependent enhancement of the Coxsackievirus B4E2-infection of human peripheral blood cells.

It has been previously shown that antibodies contained in human plasma directed towards the Coxsackievirus B4 (CVB4)E2 capsid protein VP4 can enhance the CVB4E2-induced production of IFN-alpha by peripheral blood mononuclear cells (PBMC). The aim of this study was to produce a VP4 fusion protein to investigate the role of the internal capsid protein VP4 and anti-VP4 antibodies in the plasma-dependent enhancement of CVB4E2 infection of PBMC. A fusion protein MBPVP4 containing the VP4 insert of CVB4E2 and a control fusion protein MBP-beta-gal-alpha, were produced in Escherichia coli K12 TB1.

Thymidine analogue mutations in antiretroviral-naive HIV-1 patients on triple therapy including either zidovudine or stavudine.

Aims: The aims of this study were to: (i) determine the incidence of thymidine-associated mutations (TAMs) in an observational clinical cohort of naive HIV-1 patients who stopped first-line therapy including either zidovudine or stavudine; and (ii) assess the immunological and virological responses to subsequent second-line therapy in patients who switched from zidovudine to stavudine or conversely.

Patients And Methods: Plasma samples from 165 patients who stopped first-line antiretroviral therapy containing either zidovudine or stavudine were examined for the presence of drug-resistant genotypes. Subsequent second-line immunological and virological follow-up was performed in 136 patients who switched from zidovudine to stavudine and conversely.

Multicenter quality control for the detection of hepatitis C virus RNA in seminal plasma specimens.

The discrepant results available in the literature about the presence of hepatitis C virus (HCV) RNA in seminal plasma of men chronically infected by this agent are related, at least in part, to the molecular techniques used and particularly to the wide range of protocols dedicated to RNA extraction. In order to evaluate these protocols and to standardize the method of detection of HCV RNA in this fluid, a panel of coded specimens was tested blindly in 12 French laboratories; it included 14 seminal plasma specimens and four water controls spiked with HCV RNA ranging from 10 to 20000 IU/ml and two HCV-negative seminal plasma specimens. The extraction step was performed according to methods using either silica beads (NucliSens [Organon Teknika S.

Circulating and cell-bound antibodies increase coxsackievirus B4-induced production of IFN-alpha by peripheral blood mononuclear cells from patients with type 1 diabetes.

Increased levels of IFN-alpha have been found in patients with type 1 diabetes who have detectable levels of coxsackievirus B4 (CVB4) RNA in their blood. The IFN-alpha-inducing activity of CVB4 in vitro is weak but can be enhanced by human IgGs. Therefore, it was investigated in vitro whether a preferential IFN-alpha response of peripheral blood mononuclear cells (PBMCs) to CVB4 exists in patients with type 1 diabetes (n=56) compared with healthy subjects (n=20) and whether antibodies play a role.

Semiquantitative detection of JCV-DNA in peripheral blood leukocytes from HIV-1-infected patients with or without progressive multifocal leukoencephalopathy.

Progressive Multifocal Leukoencephalopathy (PML) is a severe and fatal demyelinating disease that occurs especially in HIV-infected patients. It has been suggested that JC virus (JCV) migrates in peripheral blood leukocytes from the kidney to the central nervous system where it initiates demyelination. To investigate the physiopathological role of the peripheral blood virus in the development of PML, the prevalence of JCV infection and the levels of JCV DNA load were evaluated in peripheral blood leukocytes or mononuclear cells of 10 AIDS patients at the time of onset of PML symptoms, and in 150 non-PML HIV-1-infected patients using a semiquantitative PCR and ELISA-hybridization assay.

Human antibodies isolated from plasma by affinity chromatography increase the coxsackievirus B4-induced synthesis of interferon-alpha by human peripheral blood mononuclear cells in vitro.

Coxsackievirus B4 (CVB4) can be found in circulating blood of patients; however, the interaction of CVB4 with peripheral blood mononuclear cells (PBMCs) is poorly understood. CVB4 induced low levels of IFN-alpha synthesis in PBMCs from healthy donors. In contrast, preincubation of infectious CVB4 with plasma from these donors containing anti-CVB4 antibodies strongly enhanced the synthesis of IFN-alpha.