IgG-derived Fc down-regulates virus-induced plasmacytoid dendritic cell (pDC) IFNalpha production.

Interferon alpha (IFNalpha) produced primarily by plasmacytoid dendritic cells (pDC) is a potent component of the anti-viral innate immune response, and modulates adaptive immunity. Primary control of IFNalpha production occurs at a cellular level and is highly dependent upon regulatory factors and their products. Recent studies have identified up-regulation of IFNalpha production mediated by the adaptive immune response in the form of immune specific IgG.

Immune-specific immunoglobulin G-mediated enhancement of human immunodeficiency virus-induced IFN-alpha production.

Interferon-alpha (IFN-alpha) is synthesized as an integral part of innate immunity to viral infection. We previously provided preliminary evidence that antibody-containing serum from HIV-infected individuals enhanced HIV-induced production of IFN-alpha. Subsequently, preparations of pooled human immunoglobulin G (IgG) have also been shown to enhance poliovirus (PV)-induced IFN-alpha production.