Latent Kaposi's Sarcoma-Associated Herpesvirus Infection of Monocytes Downregulates Expression of Adaptive Immune Response Costimulatory Receptors and Proinflammatory Cytokines

Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.
Journal of Virology (Impact Factor: 4.65). 01/2012; 86(7):3916-23. DOI: 10.1128/JVI.06437-11
Source: PubMed

ABSTRACT Kaposi's sarcoma-associated herpesvirus (KSHV) infection is associated with the development of Kaposi's sarcoma, primary effusion lymphoma, and multicentric Castleman's disease. We report the establishment of a monocytic cell line latently infected with KSHV (KSHV-THP-1). We profiled viral and cytokine gene expression in the KSHV-THP-1 cells compared to that in uninfected THP-1 cells and found that several genes involved in the host immune response were downregulated during latent infection, including genes for CD80, CD86, and the cytokines tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β). Thus, KSHV minimizes its immunological signature by suppressing key immune response factors, enabling persistent infection and evasion from host detection.

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Available from: Dirk P Dittmer, Aug 18, 2015
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    • "Previous studies by our group demonstrate that HHV-8 infection of MDDC in vitro reduces their level of endocytosis as well as inhibits their ability to activate virus-specific CD8 + T cells (Rappocciolo et al., 2006a). In addition, Gregory et al. (2012) established latent HHV-8 infection of a monocyte cell line in vitro as a model to study the impact of HHV-8 on monocyte function. Latent viral infection of the monocyte cell line was associated with a dampened inflammatory and adaptive immune response, indicated by a decrease in proinflammatory cytokine production and monocyte co-stimulatory molecule expression associated with T cell activation. "
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