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bioRxiv · 10.1101/2020.09.01.277517

Negeviruses reduce replication of alphaviruses during co-infection

Patterson, E. I.·Kautz, T. F.·Contreras-Gutierrez, M. A.·Guzman, H.·Tesh, R. B.·Hughes, G. L.·Forrester, N. L.
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Abstract

Negeviruses are a group of insect-specific virus (ISV) that have been found in many arthropods. Their presence in important vector species led us to examine their interactions with arboviruses during co-infections. Wild-type negeviruses reduced the replication of Venezuelan equine encephalitis virus (VEEV) and chikungunya virus (CHIKV) during co-infections in mosquito cells. Negev virus (NEGV) isolates were also used to express GFP and anti-CHIKV antibody fragments during co-infections with CHIKV. NEGV expressing anti-CHIKV antibody fragments was able to further reduce replication of CHIKV during co-infections, while reductions of CHIKV with NEGV expressing GFP were similar to titers with wild-type NEGV alone. These results are the first to show that negeviruses induce superinfection exclusion of arboviruses, and to demonstrate a novel approach to deliver anti-viral antibody fragments with paratransgenic ISVs. The ability to inhibit arbovirus replication and express exogenous proteins in mosquito cells make negeviruses a promising platform for control of arthropod-borne pathogens.

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Patterson, E. I., Kautz, T. F., Contreras-Gutierrez, M. A., Guzman, H., Tesh, R. B., Hughes, G. L., Forrester, N. L.. 2020-09-01. Negeviruses reduce replication of alphaviruses during co-infection. https://doi.org/10.1101/2020.09.01.277517

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