Dottorato in Medicina Molecolare

The Intracellular DNA Sensor IFI16 Gene Acts as Restriction Factor for Human Cytomegalovirus Replication. G. R. Gariano, V. Dell’Oste, M. Bronzini, D. Gatti, A. Luganini, M. De Andrea, G. Gribaudo, M. Gariglio and S. Landolfo. PLoS Pathog. 2012 Jan;8(1):e1002498. Epub 2012 Jan 26.
Interplay between human cytomegalovirus and intrinsic/innate host responses: a complex bidirectional relationship. Giada Rossini, Cristina Cerboni, Angela Santoni, Maria Paola Landini, Santo Landolfo, Deborah Gatti, Giorgio Gribaudo, and Stefania Varani. Mediators of Inflammation. (In press)

October 9-12, 2011 9th Joint Meeting of ICS-ISICR , Florence “Cytokines and interferons: from the bench to the bedside”. (POSTER) Grazia Rosaria Gariano¹*, Deborah Gatti ¹*, Valentina Dell’Oste^1,3, Marco De Andrea^1,2, Anna Luganini¹, Matteo Bronzini¹, Giorgio Gribaudo¹, Marisa Gariglio² and Santo Landolfo¹. ¹Department of Public Health and Microbiology, Medical School of Torino, Italy; ²Department of Clinical and Experimental Medicine, Medical School of Novara, Italy; ³NoToPharm Srl, Bioindustry Park del Canavese, Colleretto Giacosa-Turin, Italy. Human Cytomegalovirus induces redistribution of the interferon inducible protein IFI16 from nucleus to cytoplasm. Many mammals, including humans, are equipped with genes encoding so-called “restriction factors” that provide considerable resistance to viral infections. To address the role of the interferon-inducible gene IFI16, a member of the HIN-200 gene family, in viral replication, primary human embryo lung fibroblasts (HELFs) containing a knockdown of IFI16 were analyzed for their capacity to support the replication of HCMV. Virus yield appeared significantly increased compared to that observed in cells expressing non-specific shRNA. Consistent with these results, overexpression of IFI16 down-regulated viral replication. In addition a Western blot analysis revealed that HCMV infection of HELFs induced the up-regulation of IFI16 expression as early as 48 hours post infection, that continued to increase until 96 hours post infection and disappeared thereafter. To explain this phenomenon an immunofluorescence assay was performed to observe IFI16 localization during HCMV infection. Moreover we studed the potential co-localization of IFI16 with different viral proteins such as IEA, UL44, pp65 and gB. The immunofluorescence analysis of HELF infected with HCMV revelated the de-localization of IFI16 from the nucleus to the cytoplasm,  and its interesting co-localization with the viral protein gB, but not with the other proteins tested . Using two different approches to block viral infection we than verified if IFI16 egress from nucleus is an HCMV-dependent phenomenon: we analyse by immunofluorescence assay HCMV infected cells treated with PFA and GCV, that inhibit the progression of virus replicative cycle, and HELF infected with HCMV UV-inactivated. These analysis demonstrated a dead loss of IFI16 de-localization, in both the experimental approach. Taken together these results strongly suggest that IFI16 egression from nucleus to cytoplasm is an HCMV-dependent phenomenon. 

October 13-14, 2011 Monash University Prato Centre, Prato, Italy. ISICR Sponsor Satellite Sumposium “Interferon Stimulated Genes and their Protein Products”.
October 9-12, 2011 9th Joint Meeting of ICS-ISICR “Cytokines and interferons: from the bench to the bedside”.
October 17-20, 2010 38° Congresso Nazionale della Società Italiana di Microbiologia.

April 28, 2011, Turin. Katryn Stacey: “DNA in the wrong places signals danger: Foreign cytoplasmic DNA leads to inflammation and cell death”.