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Cuvry, A.

Publications and source records attributed to Cuvry, A..

3 recordsLinked to original sources
bioRxiv2022

The dissemination of Rift Valley fever virus to the eye and sensory neurons of zebrafish larvae is stat1 dependent.

The Rift Valley fever virus (RVFV) is listed by the WHO as priority disease and causes haemorrhagic fever, encephalitis, and permanent blindness. To study RVFV pathogenesis and identify small-molecule antivirals, we established a novel in vivo model using zebrafish larvae. Pericardial injection of RVFV resulted in ~4 log10 viral RNA copies/larva, which was inhibited by antiviral 2'-fluoro-2'-deoxycytidine. The optical transparency of the larvae allowed detection of RVFVeGFP in the liver and sensory nervous system, including the optic tectum and retina, but not the brain or spinal cord. Thus, RVFV-induced blindness likely occurs due to direct damage to the eye and peripheral neurons, rather than the brain. Treatment with JAK-inhibitor ruxolitinib, as well as knockout of stat1a but not stat1b, enhanced RVFV replication to ~6 log10 viral RNA copies/larva and ultra-bright livers, although without dissemination to sensory neurons or the eye, hereby confirming the critical role of stat1 in RVFV pathogenesis.

microbiology↗
bioRxiv2022

Ex vivo midgut cultures of Aedes aegypti are efficiently infected by mosquito-borne alpha- and flaviviruses

Aedes aegypti mosquitoes can transmit several arboviruses, including chikungunya virus (CHIKV), dengue virus (DENV), and Zika virus (ZIKV). When blood-feeding on a virus-infected human, the mosquito ingests the virus into the midgut (stomach), where it replicates and must overcome the midgut barrier to disseminate to other organs and ultimately be transmitted via the saliva. Current tools to study mosquito-borne viruses (MBVs) include 2D-cell culture systems and in vivo mosquito infection models, which offer great advantages, yet have some limitations. Here, we describe a long-term ex vivo culture of Ae. aegypti midguts. Cultured midguts were metabolically active for 7 days in a 96-well plate at 28{degrees}C and were permissive to ZIKV, DENV, Ross River virus (RRV) and CHIKV. Ex vivo midguts from Culex pipiens mosquitoes were found to be permissive to Usutu virus (USUV). Immunofluorescence staining confirmed viral protein synthesis in CHIKV-infected midguts of Ae. aegypti. Furthermore, fluorescence microscopy revealed replication and spread of a reporter DENV in specific regions of the midgut. In addition, two known antiviral molecules, {beta}-D-N4-hydroxycytidine (NHC) and 7-deaza-2-C-methyladenosine (7DMA), were able to inhibit CHIKV and ZIKV replication, respectively, in the ex vivo model. Together, our results show that ex vivo midguts can be efficiently infected with mosquito-borne alpha- and flaviviruses and employed to evaluate antiviral drugs. Furthermore, the setup can be extended to other mosquito species. Ex vivo midgut cultures could thus be a new model to study MBVs, offering the advantage of reduced biosafety measures compared to infecting living mosquitoes. ImportanceMosquito-borne viruses (MBVs) are a significant global health threat since they can cause severe diseases in humans, such as hemorrhagic fever, encephalitis, and chronic arthritis. MBVs rely on the mosquito vector to infect new hosts and perpetuate virus transmission. No therapeutics are currently available. The study of arbovirus infection in the mosquito vector can greatly contribute to elucidating strategies for controlling arbovirus transmission. This work investigated the infection of midguts from Aedes aegypti mosquitoes in an ex vivo platform. We found several MBVs capable of replicating in the midgut tissue, including viruses of major health importance, such as dengue, chikungunya, and Zika viruses. Additionally, antiviral compounds reduced arbovirus infection in the cultured midgut tissue. Overall, the midgut model emerges as a useful tool for diverse applications such as studying tissue-specific responses to virus infection and screening potential anti-arboviral molecules.

molecular biology↗
bioRxiv2019

A robust human norovirus replication model in zebrafish larvae

Human noroviruses (HuNoVs) are an important cause of epidemic and endemic acute gastroenteritis worldwide; annually about 700 million people develop a HuNoV infection resulting in [~]219,000 deaths and a societal cost estimated at 60 billion US dollars 1. The lack of robust small animal models has significantly hindered the understanding of norovirus biology and the development of effective therapeutics against HuNoV. Here we report that HuNoV GI and GII replicate to high titers in zebrafish (Danio rerio) larvae; replication peaks at day 2 post infection and is detectable for at least 6 days. HuNoV is detected in cells of the hematopoietic lineage, the intestine, liver and pancreas. Antiviral treatment reduces HuNoV replication by >2 log10, showing that this model is suited for antiviral studies. Downregulation of fucosyltransferase 8 (fut8) in the larvae reduces HuNoV replication, highlighting a common feature with infection in humans. Zebrafish larvae constitute a simple and robust replication model that will largely facilitate studies of HuNoV biology and the development of antiviral strategies.

microbiology↗