Live viral vaccine viruses
Our work is focused on:
- control testing of vaccines
- underpinning research and development projects
- biological standardisation
Viral vaccines prevent diseases caused by viruses. They work by inducing an immune response against the viruses in vaccinated people, imitating a natural infection without causing the illness. This helps the body’s immune system to fight off future infections by the natural, ‘wild’ viruses.
A number of viral vaccines types are currently approved for use in the UK, containing different components to build immunity against viral diseases:
- live, attenuated viruses
- inactivated or killed viruses
- fragments (subunits) of viruses
- genetic material (nucleic acids) of viruses
- vectors that deliver viral genes to build immunity
The focus of our group is on the first type – live, attenuated vaccine viruses – in particular vaccines against rotavirus, varicella zoster virus, measles, mumps and rubella(MMR)virusinfections, but we also study the other types of viral vaccines.
Standardisation
We prepare, validate and provide reference materials to standardise laboratory assays that detect viruses and anti-virus antibodies. We also perform long-term stability studies for reference materials and we organise collaborative studies to assess new references and methods.
Control testing
We independently test a number of viral vaccines, including vaccines against SARS-CoV-2, rotavirus, measles, mumps and rubella (MMR) and varicella zoster vaccines for UK batch release and for the World Health Organisation (WHO). We also carry out contract testing for other organisations on request and have the expertise to investigate problems with products as they arise. We perform tests to assess the integrity of anti-rubella antibody preparations.
The team runs the Virology cell laboratory and provides about 20 mammalian cell lines for the control, research and standardisation work in the division. This is done according to the requirements of ISO 9001.
Research and development
Vaccine manufacturers prepare live viral vaccines in specialised cell cultures which allow the viruses to be grown and produced in large quantities.
The vaccine viruses are attenuated. This means that they have been weakened by adaptation to the cell substrates, their virulent properties have been disabled and they are less dangerous than the naturally occurring viruses while still making recipients of the vaccine immune.
Producing live viral vaccines risks introducing unwanted mutations or adventitious agents during the growth of the viruses in the cells.
It is a mandatory regulatory requirement for manufacturers to test their products for contamination with unwanted viruses and for consistency of quality. We are developing next generation sequencing – NGS or deep sequencing – and reference materials to support the application of this novel tool for regulatory work and for research purposes.
PhD students play an important role in our team. As part of an Institute-funded PhD programme in partnership with Imperial College, we undertook fundamental research that helped us understand how mumps virus populations change during propagation. Another recent PhD project studied different cell-based models for mumps virus growth. In addition, we investigate public health issues associated with live viral vaccines.
We collaborate with other teams across the Institute on a number of research and development projects: