STAT4 Regulates Antiviral Gamma Interferon Responses and Recurrent Disease during Herpes Simplex Virus 2 Infection

Department of Rheumatology & Inflammation Research, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Journal of Virology (Impact Factor: 4.44). 06/2012; 86(17):9409-15. DOI: 10.1128/JVI.00947-12
Source: PubMed


STAT4 is an important transcription factor that contributes to the incidence and severity of different autoimmune diseases
and is implicated in the antiviral immune responses in mice. In this study, we evaluated the role of STAT4 in human and murine
herpes simplex virus 2 (HSV-2) infections. We show that STAT4 regulates antiviral gamma interferon (IFN-γ) responses and disease
severity during chronic HSV-2 infections in humans and vaccine-induced IFN-γ-mediated protection against HSV-2 infection in
mice. In a cohort of 228 HSV-2-infected individuals, representing both patients with recurrent disease and asymptomatic HSV-2
carriers, we found that genetic variations in the STAT4 gene were associated with asymptomatic HSV-2 infection, as well as with increased in vitro secretion of IFN-γ in response to the virus. Mice that lacked STAT4 had impaired HSV-2-specific IFN-γ production and delayed-type
hypersensitivity responses following vaccination, which led to impaired viral clearance in the genital tract of vaccinated
animals after a genital HSV-2 challenge. We conclude that STAT4 plays an important role in IFN-γ-mediated HSV-2-specific immunity,
affecting the severity of genital HSV-2 infection.

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Available from: Inger Nordström, Dec 19, 2013
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