Oxford, UK-based Oxford Immunotec’s T-Spot Discovery SARS-CoV-2 kit will be used for T cell testing in the UK Com-COV trial. The company is collaborating with the Oxford Vaccine Group, part of the team that developed the Oxford-AstraZeneca vaccine, who is leading the Com-COV trial.
The trial will help understanding of the effects on the immune response when different combinations of approved covid-19 vaccines are administered for the first and second immunization doses. This study is funded by the UK Vaccine Task Force and the National Institute for Health Research (NIHR).
The Com-COV trial aims to understand how well people’s immune systems respond when they are primed with one type of vaccine, then boosted with another and to see how effective the response is when the second dose is separated from the first dose by different periods of time. The study will also examine how common vaccine reactions, such as fever, are after such “mixed” schedules. The first stage of this program has already recruited 830 participants, but has recently been expanded to include a second stage recruiting an additional 1,050, aged over 50, who will have a complete analysis of their immune response to vaccination carried out (including T cells). Combining vaccines might give broader, longer-lasting immunity against the virus and new variants of it.
The study will also give useful information about extending the gap between prime and boost as well as a better understanding of whether combining different vaccines creates a more flexible immunization program, potentially allowing more people to be immunized more quickly. The vaccines being examined in the study are AstraZeneca ChadOx1 nCoV-19, Pfizer BioNTech BNT162b2, the Moderna mRNA vaccine, and the protein adjuvant vaccine produced by Novavax.
The custom version of the company’s T-Spot Discovery SARS-CoV-2 kit (for research use only) will be used to assess if the vaccination combinations induce a T cell response in study subjects. The kit uses the T-Spot technology platform, a commercialized, standardized ELISPOT platform, which allows for the reproducible measurement of T cells reactive to SARS-CoV-2. Testing for an immune response using T cells may offer several advantages over conventional antibody testing due to the limitations reported with antibody testing. Of particular importance is that T cells have been shown to be long lived, whereas antibodies can wane over time. This could give an added importance to longer-term T cell testing well after initial infection. The T-Spot Discovery SARS-CoV-2 test has also demonstrated in previous studies that a high SARS-CoV-2 specific T cell response may be associated with protection from infection.
“We are proud to be partnering with the Oxford Vaccine Group on this critical clinical trial,” says Peter Wrighton-Smith, PhD, CEO of Oxford Immunotec. “Measuring the T cell response in a standardized way is vital for a complete understanding of the immune response to vaccines and will help drive the understanding of the most effective immunization program.”
Featured image: T-Spot Discovery SARS-CoV-2 kit, for research use only. (Courtesy: Oxford Immunotec)