Affinity profiling of antibody responses against SARS-CoV-2
Dr Vasilis Kosmoliaptsis
Samples and data
Institution or company
Cambridge University Hospital NHS Foundation Trust`
Detection and characterisation of antibodies in biological samples is a key requirement of clinical diagnostics and underpins risk assessment and clinical decision making in infectious diseases. Two fundamental properties of the antibody response to pathogens are its magnitude (antibody concentration) and its strength (affinity of antibody binding to its target protein). However, these properties are difficult to quantify directly using the currently available immunoassays for antibody detection. We have recently developed a novel immunoassay that enables measurement of antibody concentration and of affinity of binding directly in patient serum and under physiological conditions i.e. without the need for immobilisation of target proteins on artificial surfaces that can influence the measured signal. In a small pilot study, we found that patients infected with SARS-CoV-2 (the virus causing COVID-19) develop antibody responses that vary widely in their binding affinity to viral proteins. We now wish to use our immunoassay to profile antibody responses in a large cohort of patients with different COVID-19 disease severity (from asymptomatic to severe disease) and in healthy individuals that undergo vaccination against SARS-CoV-2. We anticipate that this study will increase our understanding of the nature and variability of immune responses against this virus in different individuals and provide important clues to help define the adequacy of immune protection after SARS-CoV-2 infection and after vaccination.