This project will use reverse genetics systems to study the role of genes involved in viruses responsible for causing endemic diseases in poultry. This will involve studying the role of the genes in the biology of the viruses, their transmission and in pathogenicity. The work will allow the rational development of molecularly defined vaccines and generation of diagnostic reagents. Other aspects of the work will involve the identification interactions between viral and host proteins to help understand their role in pathogenicity. The ultimate outcomes of the studies will provide information for the development of new generations of vaccines against avian viruses using novel approaches.

The entomology group will act as a focus for studying the interactions between arboviruses of international importance and their arthropod vectors. These studies will range from field-based investigations that define vector capacity of arthropods under known environmental conditions for horizon scanning purposes to laboratory experimentation that will provide a detailed and fundamental understanding of vector-arbovirus interactions. Primary areas of focus in the field will include studies of dispersal, diel periodicity, host location, seasonality and overwintering capability of adult vectors and habitat association investigations of immature stages. These studies will enable the construction of arbovirus transmission and dispersal models by the mathematical biology group at IAH and also contribute to wider global studies of vector-borne disease. In the laboratory there will be a focus on defining vector competence using standardised methodologies and integrating the work of other groups at IAH and beyond to understand the genetic and immunological basis of this parameter. Projects conducted will have a global focus in part driven by collaboration with the non-vesicular reference laboratory based at IAH, as well as generating data specifically designed to produce risk assessments of arbovirus incursion into the UK. While studies are currently primarily focussed upon Culicoides biting midges and the arboviruses they transmit (not least due to recent outbreaks of bluetongue virus and Schmallenberg virus in the UK), the entomology group will also widen its remit to include studies of other biological vectors such as mosquitoes and ticks. The group will also pursue an increased focus on mechanical vectors of arboviruses as a relatively neglected area of study.

We propose to use novel approaches for AI vaccination using recombinant herpesvirus of turkey (HVT) and avian infectious bronchitis virus (IBV) as vaccine vectors that express protective haemagglutinin (HA) and neuraminidase (NA) antigens of avian influenza virus. Since these vaccine constructs will express only selected AI antigen, vaccinated birds can be unambiguously differentiated from those infected with the field virus. These virus vectors have several distinct advantages: (1) they are extensively used as live virus vaccines. (2) they induce immunity following in ovo vaccine application. (3) it is relatively easy to generate new vaccines from the specific field isolates. Recombinant HVT and IBV vectors will be generated by cloning HA and NA genes (the multiple basic amino acids at the HA1 & HA2 cleavage sites will be deleted) from the HPAI viruses, [A/os/Italy 984/00 (H7N1) and A/ty/Turkey/1/05 (H5N1)], into the HVT and IBV genomes using in house derived reverse genetics systems. We plan to generate a panel of recombinant viruses (1) HVT/H7/N1 (2) HVT/H5/N1 (3) IBV/H7 (4) IBV/H5 (5) IBV/N1 for use as potential vaccine candidates. The recombinant viruses will be evaluated for expression of the AI-derived HA and NA genes in cell culture and in ovo. Selected viruses will be used in homologous virus challenge studies in chickens for comparison with commercially available inactivated vaccines. The protection parameters of the vaccines candidates will be assessed by comparing the immune responses, mortality rates, morbidity and shedding of AI virus from the challenged birds. The data obtained from these experiments will enable us to select the most effective vaccine candidate providing protection against challenge with HPAI AI virus and decrease in excretion of the AI virus. Ultimately, we anticipate that these novel AI vaccines will be used in the eradication of AI by the control of disease and reduction of viral load in the environment.

This project will investigate signalling cascades and transcriptional control using the chicken immune system as a model. Specifically, we will aim to investigate a) the role of Notch signalling within the avian immune system in health and after viral infection and b) the molecular mechanisms controlling cytosine modifying enzymes with an outlook to improve antibody diversity and viral protection in chicken B-cells.

Studentship; PB1-F2 is a 90 amino acid protein discovered in 2001 to be expressed from the second influenza genome segment in a +1 reading frame from the main protein PB1. Since then several different functions have been attributed to the protein including pro-apoptotic, interferon modulator, viral polymerase activity modulator and an inflammatory inducer. These functions have mostly been prescribed to the laboratory adapted influenza strain PR8 in mammalian cell lines. Recent work has shown that the PB1-F2 protein from other strains of influenza virus don’t behave in the same way. PB1-F2 is well conserved in avian influenza isolates in contrast to its frequent truncation or deletion in swine and human isolates. Therefore it stands that in the avian host PB1-F2 has an important function. Avian influenza makes frequent incursions into poultry populations resulting in economical and health burdens for farmers. In our fight to protect poultry populations from avian influenza it is important to understand any virulence factors in avian influenza strains so proper prevention and mitigation strategies can be developed. This PhD will look at several different aspects to do with PB1-F2 function in poultry to help shed some light on what it does and whether it is a virulence factor. The impact of PB1-F2 on viral replication kinetics and innate immune evasion will be investigated as well as trying to identify potentially new interactions that it may be involved in. Whilst investigating the question of PB1-F2 the PhD student will develop and use biologically relevant culture systems including immortalised chicken cell lines, primary mono-cultures, well differentiated respiratory and enteric tract cultures and ex vivo explants.