Molecular and cellular biology of the nairovirus Nairobi sheep disease virus/Ganjam virus

Lead Research Organisation: The Pirbright Institute
Department Name: UNLISTED


Nairobi sheep disease virus (NSDV) (called Ganjam virus (GV) on the Indian subcontinent) is a bunyavirus of the genus Nairovirus. It causes a severe haemorrhagic disease in sheep and goats, similar to the disease caused by the closely related human pathogen Crimean Congo hemorrhagic fever virus (CCHFV). Like CCHFV, NSDV is spread entirely by Ixodid (hard) ticks. The virus appears to be widespread in East and central Africa and in India. In addition to the threat posed by NSDV to livestock in the developing world, studies on this virus provide us with an important and useful model for CCHFV, since the latter is a BSL4 virus with no natural animal model.
We are characterising the pathogenesis of NSDV/GV in sheep and the way the virus modulates the host innate immune system, with the long-term goal of understanding the nature of of the pathogenic effects caused by the virus and how we might be able to interfere with that pathogenesis. We are also studying the growth of the virus in cell culture to enable us to relate observations in the host animal with specific responses in cells. Complementing the work on the whole virus, we are developing tools to study the molecular biology of the virus.
In the longer term, we will characterise the growth of the virus in the cells of its tick vectors, using both tick cell cultures and eventually ticks themselves, work to be carried out in conjunction with the Tick Cell Biobank.
Description We have developed systems for expressing all the viral proteins in a controled manner in a cell. We have developed entirely novel protocols which allow us to model the genome replication and transcription in this group of viruses.
Exploitation Route It would be very helpful to complete the construction of a reverse genetics system for this virus, which would enable us to investigate targeted mutations/deletion in the virus, investigating both in the mammalian host and the tick vector.
Sectors Agriculture, Food and Drink,Pharmaceuticals and Medical Biotechnology