scholarly journals ATIM-32. PREDICTORS OF IMPROVED SURVIVAL FOLLOWING ONCOLYTIC VIRUS TREATMENT IN PATIENTS WITH RECURRENT GLIOBLASTOMA: GENE EXPRESSION ANALYSIS FROM THE PHASE IB G207 CLINICAL TRIAL

2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi8-vi8
Author(s):  
Kevin Cassady ◽  
Katherine Miller ◽  
Nripesh Prasad ◽  
Dragan Maric ◽  
Josh Bernstock ◽  
...  
Keyword(s):  
Gene Expression ◽  
Viral Gene Expression ◽  
Recurrent Glioblastoma ◽  
Viral Gene ◽  
Early Generation ◽  
Therapeutic Success ◽  
Phase Ib ◽  
Tumor Microenvironments ◽  
Pre Treatment ◽  
Simplex Virus

Abstract Our Phase I trials of experimental virotherapy for recurrent glioblastoma (GBM) have shown that inoculation with a conditionally replication-competent early generation oncolytic herpes simplex virus (oHSV), G207, is safe. However, while 17 of 37 subjects experienced objective clinical responses, the highly attenuated oHSV did not uniformly improve survival. We sought to identify predictors that would identify mechanisms contributing to survival and improve future trial design, by studying accrued samples. We analyzed pre-treatment biopsy and post-G207-treatment tumor samples (collected D2-5 post injection) banked from the patients enrolled in the phase IB G207 trial. The key findings from these patients suggest that productive G207 infection and G207-induced changes in gene expression were predictive of oHSV therapeutic success. RNAseq-based transcriptome analysis of these samples revealed that both the intrinsic IFN mediated antiviral response and adaptive immune functional response in patients correlated significantly with improved survival following G207 inoculation. Further, GBM tissue stained using multiplex fluorescent immunohistochemistry supported differences in the tumor microenvironments that were identified from RNAseq data analysis. Our data indicate that both viral gene expression and the resulting intrinsic anti-viral and recruited adaptive response were critical for survival after G207 inoculation and predict survival with this early generation oHSV in patients with recurrent malignant glioma.

scholarly journals Herpes Simplex Virus Latency Is Noisier the Closer We Look

2019 ◽  
Vol 94 (4) ◽  
Author(s):  
Navneet Singh ◽  
David C. Tscharke
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Genome ◽  
Infectious Virus ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Peripheral Neurons ◽  
Virus Latency ◽  
Simplex Virus

ABSTRACT During herpes simplex virus (HSV) latency, the viral genome is harbored in peripheral neurons in the absence of infectious virus but with the potential to restart infection. Advances in epigenetics have helped explain how viral gene expression is largely inhibited during latency. Paradoxically, at the same time, the view that latency is entirely silent has been eroding. This low-level noise has implications for our understanding of HSV latency and should not be ignored.

scholarly journals Viral DNA Sensors IFI16 and Cyclic GMP-AMP Synthase Possess Distinct Functions in Regulating Viral Gene Expression, Immune Defenses, and Apoptotic Responses during Herpesvirus Infection

mBio ◽  
2016 ◽  
Vol 7 (6) ◽  
Author(s):  
Benjamin A. Diner ◽  
Krystal K. Lum ◽  
Jared E. Toettcher ◽  
Ileana M. Cristea
Keyword(s):  
Gene Expression ◽  
Live Cell Imaging ◽  
Nuclear Periphery ◽  
Viral Gene Expression ◽  
Live Cell ◽  
Viral Gene ◽  
Viral Dna ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1

ABSTRACTThe human interferon-inducible protein IFI16 is an important antiviral factor that binds nuclear viral DNA and promotes antiviral responses. Here, we define IFI16 dynamics in space and time and its distinct functions from the DNA sensor cyclic dinucleotide GMP-AMP synthase (cGAS). Live-cell imaging reveals a multiphasic IFI16 redistribution, first to viral entry sites at the nuclear periphery and then to nucleoplasmic puncta upon herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV) infections. Optogenetics and live-cell microscopy establish the IFI16 pyrin domain as required for nuclear periphery localization and oligomerization. Furthermore, using proteomics, we define the signature protein interactions of the IFI16 pyrin and HIN200 domains and demonstrate the necessity of pyrin for IFI16 interactions with antiviral proteins PML and cGAS. We probe signaling pathways engaged by IFI16, cGAS, and PML using clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated knockouts in primary fibroblasts. While IFI16 induces cytokines, only cGAS activates STING/TBK-1/IRF3 and apoptotic responses upon HSV-1 and HCMV infections. cGAS-dependent apoptosis upon DNA stimulation requires both the enzymatic production of cyclic dinucleotides and STING. We show that IFI16, not cGAS or PML, represses HSV-1 gene expression, reducing virus titers. This indicates that regulation of viral gene expression may function as a greater barrier to viral replication than the induction of antiviral cytokines. Altogether, our findings establish coordinated and distinct antiviral functions for IFI16 and cGAS against herpesviruses.IMPORTANCEHow mammalian cells detect and respond to DNA viruses that replicate in the nucleus is poorly understood. Here, we decipher the distinct functions of two viral DNA sensors, IFI16 and cGAS, during active immune signaling upon infection with two herpesviruses, herpes simplex virus 1 (HSV-1) and human cytomegalovirus (HCMV). We show that IFI16 rapidly oligomerizes at incoming herpesvirus genomes at the nuclear periphery to transcriptionally repress viral gene expression and limit viral replicative capacity. We further demonstrate that IFI16 does not initiate upstream activation of the canonical STING/TBK-1/IRF3 signaling pathway but is required for downstream antiviral cytokine expression. In contrast, we find that, upon DNA sensing during herpesvirus infection, cGAS triggers apoptosis in a STING-dependent manner. Our live-cell imaging, mass spectrometry-based proteomics, CRISPR-based cellular assays, and optogenetics underscore the value of integrative approaches to uncover complex cellular responses against pathogens.

scholarly journals Chromatin Modulation of Herpesvirus Lytic Gene Expression: Managing Nucleosome Density and Heterochromatic Histone Modifications

mBio ◽  
2016 ◽  
Vol 7 (1) ◽  
Author(s):  
Thomas M. Kristie
Keyword(s):  
Gene Expression ◽  
Histone Modifications ◽  
Viral Gene Expression ◽  
Virus Genome ◽  
Early Gene ◽  
Productive Infection ◽  
Viral Gene ◽  
Early Protein ◽  
Protein Icp0 ◽  
Simplex Virus

ABSTRACT Like their cellular hosts, herpesviruses are subject to the regulatory impacts of chromatin assembled on their genomes. Upon infection, these viruses are assembled into domains of chromatin with heterochromatic signatures that suppress viral gene expression or euchromatic characteristics that promote gene expression. The organization and modulation of these chromatin domains appear to be intimately linked to the coordinated expression of the different classes of viral genes and thus ultimately play an important role in the progression of productive infection or the establishment and maintenance of viral latency. A recent report from the Knipe laboratory (J. S. Lee, P. Raja, and D. M. Knipe, mBio 7:e02007-15, 2016) contributes to the understanding of the dynamic modulation of chromatin assembled on the herpes simplex virus genome by monitoring the levels of characteristic heterochromatic histone modifications (histone H3 lysine 9 and 27 methylation) associated with a model viral early gene during the progression of lytic infection. Additionally, this study builds upon previous observations that the viral immediate-early protein ICP0 plays a role in reducing the levels of heterochromatin associated with the early genes.

scholarly journals Epigenetic Repression of Herpes Simplex Virus Infection by the Nucleosome Remodeler CHD3

mBio ◽  
2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Jesse H. Arbuckle ◽  
Thomas M. Kristie
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Infection ◽  
Host Cell ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Histone Marks ◽  
Viral Genomes ◽  
Simplex Virus

ABSTRACTUpon infection, the genome of herpes simplex virus is rapidly incorporated into nucleosomes displaying histone modifications characteristic of heterochromatic structures. The initiation of infection requires complex viral-cellular interactions that ultimately circumvent this repression by utilizing host cell enzymes to remove repressive histone marks and install those that promote viral gene expression. The reversion of repression and activation of viral gene expression is mediated by the cellular coactivator HCF-1 in association with histone demethylases and methyltransferases. However, the mechanisms and the components that are involved in the initial repression remain unclear. In this study, the chromatin remodeler chromodomain helicase DNA binding (CHD3) protein is identified as an important component of the initial repression of the herpesvirus genome. CHD3 localizes to early viral foci and suppresses viral gene expression. Depletion of CHD3 results in enhanced viral immediate early gene expression and an increase in the number of transcriptionally active viral genomes in the cell. Importantly, CHD3 can recognize the repressive histone marks that have been detected in the chromatin associated with the viral genome and this remodeler is important for ultimately reducing the levels of accessible viral genomes. A model is presented in which CHD3 represses viral infection in opposition to the actions of the HCF-1 coactivator complex. This dynamic, at least in part, determines the initiation of viral infection.IMPORTANCEChromatin modulation of herpesvirus infection is a dynamic process involving regulatory components that mediate suppression and those that promote viral gene expression and the progression of infection. The mechanisms by which the host cell employs the assembly and modulation of chromatin as an antiviral defense strategy against an invading herpesvirus remain unclear. This study defines a critical cellular component that mediates the initial repression of infecting HSV genomes and contributes to understanding the dynamics of this complex interplay between host cell and viral pathogen.

scholarly journals The Nuclear DNA Sensor IFI16 Acts as a Restriction Factor for Human Papillomavirus Replication through Epigenetic Modifications of the Viral Promoters

2015 ◽  
Vol 89 (15) ◽  
pp. 7506-7520 ◽  
Author(s):  
Irene Lo Cigno ◽  
Marco De Andrea ◽  
Cinzia Borgogna ◽  
Silvia Albertini ◽  
Manuela M. Landini ◽  
...  
Keyword(s):  
Gene Expression ◽  
Herpes Simplex ◽  
Viral Gene Expression ◽  
Restriction Factor ◽  
Viral Gene ◽  
Viral Dna ◽  
Herpes Simplex Virus 1 ◽  
Hpv Dna ◽  
U2os Cells ◽  
Simplex Virus

ABSTRACTThe human interferon-inducible IFI16 protein, an innate immune sensor of intracellular DNA, was recently demonstrated to act as a restriction factor for human cytomegalovirus (HCMV) and herpes simplex virus 1 (HSV-1) infection by inhibiting both viral-DNA replication and transcription. Through the use of two distinct cellular models, this study provides strong evidence in support of the notion that IFI16 can also restrict human papillomavirus 18 (HPV18) replication. In the first model, an immortalized keratinocyte cell line (NIKS) was used, in which the IFI16 protein was knocked down through the use of small interfering RNA (siRNA) technology and overexpressed following transduction with the adenovirus IFI16 (AdVIFI16) vector. The second model consisted of U2OS cells transfected by electroporation with HPV18 minicircles. In differentiated IFI16-silenced NIKS-HPV18 cells, viral-load values were significantly increased compared with differentiated control cells. Consistent with this, IFI16 overexpression severely impaired HPV18 replication in both NIKS and U2OS cells, thus confirming its antiviral restriction activity. In addition to the inhibition of viral replication, IFI16 was also able to reduce viral transcription, as demonstrated by viral-gene expression analysis in U2OS cells carrying episomal HPV18 minicircles and HeLa cells. We also provide evidence that IFI16 promotes the addition of heterochromatin marks and the reduction of euchromatin marks on viral chromatin at both early and late promoters, thus reducing both viral replication and transcription. Altogether, these results argue that IFI16 restricts chromatinized HPV DNA through epigenetic modifications and plays a broad surveillance role against viral DNA in the nucleus that is not restricted to herpesviruses.IMPORTANCEIntrinsic immunity is mediated by cellular restriction factors that are constitutively expressed and active even before a pathogen enters the cell. The host nuclear factor IFI16 acts as a sensor of foreign DNA and an antiviral restriction factor, as recently demonstrated by our group for human cytomegalovirus (HCMV) and herpes simplex virus 1 (HSV-1). Here, we provide the first evidence that IFI16 inhibits HPV18 replication by repressing viral-gene expression and replication. This antiviral restriction activity was observed in immortalized keratinocytes transfected with the religated genomes and in U2OS cells transfected with HPV18 minicircles, suggesting that it is not cell type specific. We also show that IFI16 promotes the assembly of heterochromatin on HPV DNA. These changes in viral chromatin structure lead to the generation of a repressive state at both early and late HPV18 promoters, thus implicating the protein in the epigenetic regulation of HPV gene expression and replication.

scholarly journals Regulation of viral gene expression by the herpes simplex virus 1 UL24 protein (HSV-1 UL24 inhibits accumulation of viral transcripts)

Virology ◽  
2016 ◽  
Vol 495 ◽  
pp. 148-160 ◽  
Author(s):  
Carolina Sanabria-Solano ◽  
Carmen Elena Gonzalez ◽  
Nicolas Richerioux ◽  
Luc Bertrand ◽  
Slimane Dridi ◽  
...  
Keyword(s):  
Gene Expression ◽  
Herpes Simplex Virus ◽  
Herpes Simplex ◽  
Viral Gene Expression ◽  
Viral Gene ◽  
Herpes Simplex Virus 1 ◽  
Simplex Virus ◽  
Hsv 1
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