TY  - JOUR
A1  - Sanyal, Anirban
A1  - Wallaschek, Nina
A1  - Glass, Mandy
A1  - Flamand, Louis
A1  - Wight, Darren J.
A1  - Kaufer, Benedikt B.
T1  - The ND10 Complex Represses Lytic Human Herpesvirus 6A Replication and Promotes Silencing of the Viral Genome
JF  - Viruses
N2  - Human herpesvirus 6A (HHV-6A) replicates in peripheral blood mononuclear cells (PBMCs) and various T-cell lines in vitro. Intriguingly, the virus can also establish latency in these cells, but it remains unknown what influences the decision between lytic replication and the latency of the virus. Incoming virus genomes are confronted with the nuclear domain 10 (ND10) complex as part of an intrinsic antiviral response. Most herpesviruses can efficiently subvert ND10, but its role in HHV-6A infection remains poorly understood. In this study, we investigated if the ND10 complex affects HHV-6A replication and contributes to the silencing of the virus genome during latency. We could demonstrate that ND10 complex was not dissociated upon infection, while the number of ND10 bodies was reduced in lytically infected cells. Virus replication was significantly enhanced upon knock down of the ND10 complex using shRNAs against its major constituents promyelocytic leukemia protein (PML), hDaxx, and Sp100. In addition, we could demonstrate that viral genes are more efficiently silenced in the presence of a functional ND10 complex. Our data thereby provides the first evidence that the cellular ND10 complex plays an important role in suppressing HHV-6A lytic replication and the silencing of the virus genome in latently infected cells.
KW  - human herpesvirus 6
KW  - ND10 complex
KW  - PML
KW  - lytic replication
KW  - latency
KW  - PML nuclear-bodies
KW  - gene-expression
KW  - virus-infection
KW  - in-vitro
KW  - DNA
Y1  - 2018
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-227337
VL  - 10
IS  - 8
ER  - 
TY  - JOUR
A1  - Wallaschek, Nina
A1  - Reuter, Saskia
A1  - Silkenat, Sabrina
A1  - Wolf, Katharina
A1  - Niklas, Carolin
A1  - Özge, Kayisoglu
A1  - Aguilar, Carmen
A1  - Wiegering, Armin
A1  - Germer, Christoph-Thomas
A1  - Kircher, Stefan
A1  - Rosenwald, Andreas
A1  - Shannon-Lowe, Claire
A1  - Bartfeld, Sina
T1  - Ephrin receptor A2, the epithelial receptor for Epstein-Barr virus entry, is not available for efficient infection in human gastric organoids
JF  - PLoS Pathogens
N2  - Epstein-Barr virus (EBV) is best known for infection of B cells, in which it usually establishes an asymptomatic lifelong infection, but is also associated with the development of multiple B cell lymphomas. EBV also infects epithelial cells and is associated with all cases of undifferentiated nasopharyngeal carcinoma (NPC). EBV is etiologically linked with at least 8% of gastric cancer (EBVaGC) that comprises a genetically and epigenetically distinct subset of GC. Although we have a very good understanding of B cell entry and lymphomagenesis, the sequence of events leading to EBVaGC remains poorly understood. Recently, ephrin receptor A2 (EPHA2) was proposed as the epithelial cell receptor on human cancer cell lines. Although we confirm some of these results, we demonstrate that EBV does not infect healthy adult stem cell-derived gastric organoids. In matched pairs of normal and cancer-derived organoids from the same patient, EBV only reproducibly infected the cancer organoids. While there was no clear pattern of differential expression between normal and cancer organoids for EPHA2 at the RNA and protein level, the subcellular location of the protein differed markedly. Confocal microscopy showed EPHA2 localization at the cell-cell junctions in primary cells, but not in cancer cell lines. Furthermore, histologic analysis of patient tissue revealed the absence of EBV in healthy epithelium and presence of EBV in epithelial cells from inflamed tissue. These data suggest that the EPHA2 receptor is not accessible to EBV on healthy gastric epithelial cells with intact cell-cell contacts, but either this or another, yet to be identified receptor may become accessible following cellular changes induced by inflammation or transformation, rendering changes in the cellular architecture an essential prerequisite to EBV infection.
KW  - Organoids
KW  - ephitelial cells
KW  - gastrointestinal infections
KW  - cancers and neoplasms
KW  - Epstein-Barr virus
KW  - flow cytometry
KW  - epithelium
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259206
VL  - 17
IS  - 2
ER  -