Can we identify specific features of a patient’s immune response to COVID-19 from symptom-onset to recovery?

Bottom Line:

Specific types of immune cells and antibodies were elevated in a patient’s blood before the resolution of their symptoms from COVID-19. Following further evaluation, these immune parameters can potentially be used to predict disease outcome or evaluate efficacy of new interventions.

Reference:

Thevarajan, I. et al. Breadth of concomitant immune responses prior to patient recovery: a case report of non-severe COVID-19. Nature Medicine (2020). https://doi.org/10.1038/s41591-020-0819-2

Date Published:

16 March 2020

Synopsis:

Authors used a variety of biochemical and imaging approaches to evaluate the features of one patient’s immune response to symptomatic but non-severe COVID-19. Viral load was evaluated from nasopharyngeal, sputum, and fecal samples. Whole blood samples were evaluated for the frequency of different immune cell populations and elevation of different classes of antibodies. In this patient, the authors report that the cellular immune response was characterized by an increase in antibody secreting cells, T-follicular helper cells, and activated effector T cells (both CD4+ and CD8+) prior to resolution. The number of natural killer cells in the patient’s blood did not change appreciably over the course of disease, though there was a slight decrease in the number of circulating monocytes. Prior to disease resolution, the patient’s serum was also characterized as having elevated levels of IgG and IgM antibodies, but minimal amounts of the pro-inflammatory molecules (cytokines and chemokines) that are typical of other respiratory viral illnesses including certain strains of the flu.

Summary by: Sivakami Mylvaganam