Dense Granule Protein-7 (GRA-7) of Toxoplasma gondii inhibits viral replication in vitro and in vivo

作者：Weeratunga Prasanna; Herath Thilina U B; Kim Tae Hwan; Lee Hyun Cheol; Kim Jae Hoon; Lee Byeong Hoon; Lee Eun Seo; Chathuranga Kiramage; Chathuranga W A Gayan; Yang Chul Su; Ma Jin Yeul; Lee Jong Soo^*

来源：Journal of Microbiology, 2017, 55(11): 909-917.

DOI：10.1007/s12275-017-7392-5

• Toxoplasma gondii
• GRA-7
• antiviral activity

Dense granule protein-7 (GRA-7) is an excretory protein of Toxoplasma gondii. It is a potential serodiagnostic marker and vaccine candidate for toxoplasmosis. Previous reports demonstrated that GRA-7 induces innate immune responses in macrophages by interacting with TRAF6 via the MyD88-dependent pathway. In the present study, we evaluated the antiviral activity and induction of an antiviral state by GRA-7 both in vitro and in vivo. It was observed that GRA-7 markedly reduced the replication of vesicular stomatitis virus (VSV-GFP), influenza A virus (PR8-GFP), coxsackievirus (H3-GFP), herpes simplex virus (HSV-GFP), and adenovirus-GFP in epithelial (HEK293T/HeLa) and immune (RAW264.7) cells. These antiviral activities of GRA-7 were attributed to the induction of type I interferon (IFN) signaling, resulting in the secretion of IFNs and pro-inflammatory cytokines. Additionally, in BALB/c mice, intranasal administration of GRA-7 prevented lethal infection by influenza A virus (H1N1) and exhibited prophylactic effects against respiratory syncytial virus (RSV-GFP). Collectively, these results suggested that GRA-7 exhibits immunostimulatory and broad spectrum antiviral activities via type I IFN signaling. Thus, GRA-7 can be potentially used as a vaccine adjuvant or as a candidate drug with prophylactic potential against viruses.

• 出版日期2017-11