COVID-19 Cellular Immunity Test; Ver 1.0 [COVID-19]
Research type
Research Study
Full title
Development and Validation of a Simple Cellular Immunity Test (SCIT) for SARS-CoV-2 (COVID-19)
IRAS ID
286991
Contact name
Maria Oliver
Contact email
Sponsor organisation
IndoorBiotech
Duration of Study in the UK
3 years, 0 months, 1 days
Research summary
Research Summary
New screening tools that determine who has been infected with the SARS-CoV-2 virus are urgently required to enable the economy to return to normal. This includes identifying individuals who have already been infected without realising it, or have pre-existing immunity. \n\nIn order to gain immunity to SARS-CoV-2, an individual must generate an adequate immune response that protects from future infection. This can be measured by looking for antibodies found in blood samples that bind specifically to the virus. However, as widely reported, these tests exhibit questionable reliability. We propose a different type of immunity test, utilising existing laboratory techniques.\n\nLong-term protection against viruses not only comes from antibodies, but from cells of the immune system called ’T cells’, which play a critical role in controlling and eradicating viral infections. From a single tube of blood, we can identify the presence of T cells that respond to the SARS-CoV-2 virus in a laboratory test called a ’Simple Cellular Immunity Test’ (SCIT). This approach is potentially more sensitive at determining immunity than antibody testing, but this needs verifying on individuals that have recovered from COVID-19. \n\nWe will advertise locally for research participants to provide a small blood sample and details of their prior COVID-19 test results. We will use the blood to determine whether our laboratory test for the presence of these T cells is a feasible alternative to the antibody test for identifying individuals who have been infected with the virus and generated immunity to it. In addition, when a vaccine does become available, results from the test developed here will yield critical additional information as to whether an adequate immune response that protects individuals from SARS-CoV-2 infection has been generated.
Summary of Results
T cell immunity to natural SARS-CoV-2 infection may be more robust and longer lived than antibody responses. Accurate assessment of T cell responses is critical for understanding the magnitude and longevity of immunity across patient cohorts, and against emerging variants.
By establishing a simple, accurate and rapid whole blood test, natural and vaccine-induced SARS-CoV-2 immunity was determined.
Cytokine release in whole blood stimulated with peptides specific for SARS-CoV-2 was measured in donors with previous PCR-confirmed infection, suspected infection or with no exposure history; and in donors pre- and post-vaccination. Longitudinal assessment of T cell responses following initial vaccination was also conducted. Cytokines were measured by ELISA and multiplex array.
IL-2 and IFN-γ were highly elevated in PCR-confirmed donors compared to history negative controls, with median levels ~33-fold and ~48-fold higher, respectively. Receiver operating curves showed IL-2 as the superior biomarker. Following vaccination, all donors demonstrated a positive IL-2 response. Median IL-2 levels increased ~32-fold from pre-vaccination to post-vaccination in uninfected individuals. Longitudinal assessment revealed T cell responses were stable up to 6 months post-vaccination. No significant differences in cytokine production were observed between stimulations with Wuhan, Delta or Omicron peptides.
This rapid, whole blood-based test can be utilised to make comparable longitudinal assessments of vaccine-induced T cell immunity across multiple cohorts and against variants of concern, thus aiding decisions on public health policies.REC name
Wales REC 5
REC reference
20/WA/0217
Date of REC Opinion
17 Jul 2020
REC opinion
Favourable Opinion