Macrophage-derived extracellular vesicles mediate a long-lasting innate immune response against hepatitis C virus

2016 ◽  
Vol 54 (12) ◽  
pp. 1343-1404
Author(s):  
C Cai ◽  
B Koch ◽  
S Akhras ◽  
E Hildt ◽  
S Zeuzem ◽  
...  
Cells ◽  
2018 ◽  
Vol 7 (11) ◽  
pp. 191
Author(s):  
Emmanuelle Blanchard ◽  
Philippe Roingeard

Host cell membrane rearrangements induced by the hepatitis C virus (HCV) have been exclusively studied in vitro. These studies have shown that HCV induces double-membrane vesicles (DMVs), which probably serve to separate replication sites from the cytoplasmic sensors of the innate immune response. We report for the first time the observation of HCV-induced membrane rearrangements in liver biopsy specimens from patients chronically infected with HCV. Unlike observations performed in vitro, the membranous web detected in liver tissue seems essentially made of clusters of single-membrane vesicles derived from the endoplasmic reticulum and close to lipid droplets. This suggests that the DMVs could be a hallmark of laboratory-adapted HCV strains, possibly due to their ability to achieve a high level of replication. Alternatively, the concealment of viral RNA in DMVs may be part of innate immune response mechanisms particularly developed in hepatoma cell lines cultured in vitro. In any case, this constitutes the first report showing the differences in the membranous web established by HCV in vitro and in vivo.


Hepatology ◽  
2011 ◽  
Vol 53 (2) ◽  
pp. 406-414 ◽  
Author(s):  
Shubham Shrivastava ◽  
Amit Raychoudhuri ◽  
Robert Steele ◽  
Ranjit Ray ◽  
Ratna B. Ray

Vaccines ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 313
Author(s):  
Daniel Sepulveda-Crespo ◽  
Salvador Resino ◽  
Isidoro Martinez

Despite successful treatments, hepatitis C virus (HCV) infections continue to be a significant world health problem. High treatment costs, the high number of undiagnosed individuals, and the difficulty to access to treatment, particularly in marginalized susceptible populations, make it improbable to achieve the global control of the virus in the absence of an effective preventive vaccine. Current vaccine development is mostly focused on weakly immunogenic subunits, such as surface glycoproteins or non-structural proteins, in the case of HCV. Adjuvants are critical components of vaccine formulations that increase immunogenic performance. As we learn more information about how adjuvants work, it is becoming clear that proper stimulation of innate immunity is crucial to achieving a successful immunization. Several hepatic cell types participate in the early innate immune response and the subsequent inflammation and activation of the adaptive response, principally hepatocytes, and antigen-presenting cells (Kupffer cells, and dendritic cells). Innate pattern recognition receptors on these cells, mainly toll-like receptors, are targets for new promising adjuvants. Moreover, complex adjuvants that stimulate different components of the innate immunity are showing encouraging results and are being incorporated in current vaccines. Recent studies on HCV-vaccine adjuvants have shown that the induction of a strong T- and B-cell immune response might be enhanced by choosing the right adjuvant.


Hepatology ◽  
2014 ◽  
Vol 60 (4) ◽  
pp. 1170-1179 ◽  
Author(s):  
Benjamin Israelow ◽  
Christopher M. Narbus ◽  
Marion Sourisseau ◽  
Matthew J. Evans

2016 ◽  
Vol 291 (23) ◽  
pp. 12294-12309 ◽  
Author(s):  
Dahai Wei ◽  
Nan L. Li ◽  
Yanli Zeng ◽  
Baoming Liu ◽  
Kattareeya Kumthip ◽  
...  

2015 ◽  
Vol 90 (3) ◽  
pp. 1387-1396 ◽  
Author(s):  
Shubham Shrivastava ◽  
Pradip Devhare ◽  
Nanthiya Sujijantarat ◽  
Robert Steele ◽  
Young-Chan Kwon ◽  
...  

ABSTRACTHepatitis C virus (HCV) is a major cause of chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma in humans. We showed previously that HCV induces autophagy for viral persistence by preventing the innate immune response. Knockdown of autophagy reduces extracellular HCV release, although the precise mechanism remains unknown. In this study, we observed that knockdown of autophagy genes enhances intracellular HCV RNA and accumulates infectious virus particles in cells. Since HCV release is linked with the exosomal pathway, we examined whether autophagy proteins associate with exosomes in HCV-infected cells. We observed an association between HCV and the exosomal marker CD63 in autophagy knockdown cells. Subsequently, we observed that levels of extracellular infectious HCV were significantly lower in exosomes released from autophagy knockdown cells. To understand the mechanism for reduced extracellular infectious HCV in the exosome, we observed that an interferon (IFN)-stimulated BST-2 gene is upregulated in autophagy knockdown cells and associated with the exosome marker CD63, which may inhibit HCV assembly or release. Taken together, our results suggest a novel mechanism involving autophagy and exosome-mediated HCV release from infected hepatocytes.IMPORTANCEAutophagy plays an important role in HCV pathogenesis. Autophagy suppresses the innate immune response and promotes survival of virus-infected hepatocytes. The present study examined the role of autophagy in secretion of infectious HCV from hepatocytes. Autophagy promoted HCV trafficking from late endosomes to lysosomes, thus providing a link with the exosome. Inhibition of HCV-induced autophagy could be used as a strategy to block exosome-mediated virus transmission.


Sign in / Sign up

Export Citation Format

Share Document