September 2, 2020

expert reaction to study looking at T cell responses in people who have had COVID-19

A study, published in Nature Immunology, looked at T cell responses in people who have had COVID-19.

Prof Eleanor Riley, Professor of Immunology and Infectious Disease, University of Edinburgh, said:

“This is a well-designed and comprehensive study in which antibody responses were assessed among a large number of individuals up to 120 days after documented exposure to SARS-CoV-2.  The data show that antibody concentrations are highest in the first few weeks after infection but then decline to a lower level that is maintained for many weeks.  This sustained antibody response will result from continual, low level secretion of antibodies from long-lived antibody-producing cells.  Importantly, these antibody-producing cells continue to evolve for several weeks after initial exposure to the virus, so it is likely that the antibodies produced by these long-lived cells are qualitatively superior to the antibodies produced early on.  As the overall effectiveness of the antibody response depends both on the amount of antibody and the effectiveness of individual antibody molecules, a reduction in antibody concentration can be offset by an increase in the quality of the response over time.

“Unfortunately this study does not directly assess antibody function, for example by testing whether the antibodies effectively neutralise the virus.  So whilst the kinetics of the antibody response described here are exactly as we would expect – which is reassuring – we don’t yet know whether these antibodies are protective.  Functional analysis of the samples collected for this study would begin to provide answers to this very important question.”

‘Humoral Immune Response to SARS-CoV-2 in Iceland’ by Daniel F. Gudbjartsson et al. was published in the NEJM on Tuesday 1 September 2020. 

DOI: 10.1056/NEJMoa2026116

https://www.nejm.org/doi/full/10.1056/NEJMoa2026116

All our previous output on this subject can be seen at this weblink: 

www.sciencemediacentre.org/tag/covid-19 

Declared interests 

Prof Eleanor Riley: “No Conflicts of Interest to declare.”