Evolution of multiple sclerosis in France since the beginning of hepatitis B vaccination.

Since the implementation of the mass vaccination campaign against hepatitis B in France, the appearance of multiple sclerosis, sometimes occurring in the aftermath of vaccinations, led to the publication of epidemiological international studies. This was also justified by the sharp increase in the annual incidence of multiple sclerosis reported to the French health insurance in the mid-1990s. Almost 20 years later, a retrospective reflection can be sketched from these official data and also from the national pharmacovigilance agency. Statistical data from these latter sources seem to show a significant correlation between the number of hepatitis B vaccinations performed and the declaration to the pharmacovigilance of multiple sclerosis occurring between 1 and 2 years later. The application of the Hill’s criteria to these data indicates that the correlation between hepatitis B vaccine and multiple sclerosis may be causal.

Exosomes mediate the cell-to-cell transmission of IFN-[alpha]-induced antiviral activity : Nature Immunology

The cell-to-cell transmission of viral resistance is a potential mechanism for amplifying the interferon-induced antiviral response. In this study, we report that interferon-α (IFN-α) induced the transfer of resistance to hepatitis B virus (HBV) from nonpermissive liver nonparenchymal cells (LNPCs) to permissive hepatocytes via exosomes. Exosomes from IFN-α-treated LNPCs were rich in molecules with antiviral activity. Moreover, exosomes from LNPCs were internalized by hepatocytes, which mediated the intercellular transfer of antiviral molecules. Finally, we found that exosomes also contributed to the antiviral response of IFN-α to mouse hepatitis virus A59 and adenovirus in mice. Thus, we propose an antiviral mechanism of IFN-α activity that involves the induction and intercellular transfer of antiviral molecules via exosomes.

Retinazone inhibits certain blood-borne human viruses including Ebola virus Zaire.

Human hepatitis B and immunodeficiency viruses integrate their retro-transcribed DNA proviruses into the human host genome. Existing antiretroviral drug regimens fail to directly target these intrachromosomal xenogenomes, leading to persistence of viral genetic information. Retinazone (RTZ) constitutes a novel vitamin A-derived (retinoid) thiosemicarbazone derivative with broad-spectrum antiviral activity versus human immunodeficiency, hepatitis C, varicella-zoster and cytomegalo-viruses.

METHODS:

The in vitro inhibitory action of RTZ on HIV-1 strain LAI, human hepatitis B virus strain ayw, HCV-1b strain Con1, enhanced green fluorescent protein-expressing Ebola virus Zaire 1976 strain Mayinga, wild-type Ebola virus Zaire 1976 strain Mayinga, human herpesvirus 6B and Kaposi's sarcoma-associated herpesvirus replication was investigated. The binding of RTZ to human glucocorticoid receptor was determined.

RESULTS:

RTZ inhibits the bloodborne human hepatitis B virus multiplication in vitro by covalent inactivation of intragenic and intraexonic viral glucocorticoid response elements, and, in close analogy, RTZ suppresses HIV-1 multiplication in vitro. RTZ disrupts the multiplication of the bloodborne human hepatitis C and Ebola Zaire viruses at nanomolar concentrations in vitro. RTZ has the capacity to bind to human glucocorticoid receptor, to selectively and covalently bind to intraexonic viral glucocorticoid response elements, and thereby to inactivate human genome-integrated proviral DNA of human hepatitis B and immunodeficiency viruses.

CONCLUSIONS:

RTZ represents the first reported antiviral agent capable of eradicating human immunodeficiency and hepatitis B proviruses from their human host. Furthermore, RTZ represents a potent and efficacious small-molecule in vitro inhibitor of Ebola virus Zaire 1976 strain Mayinga replication.