Serum biomarkers for nutritional status as predictors in COVID-19 patients before and after vaccination.

Abstract

The aim of this study was to characterize serum protein biomarkers for nutritional status that may be used as predictors for disease symptomatology in COVID-19 patients before and after vaccination. In pre-vaccine cohorts, proteomics analysis revealed significant differences between groups, with serum proteins alpha-1-acid glycoproteins (AGPs) 1 and 2, C-reactive protein (CRP) and retinol binding protein (RBP) increasing with COVID-19 severity, in contrast with serum albumin, transthyretin (TTR) and serotransferrin (TF) reduction as the symptomatology increased. Immunoassay reproduced and validated proteomics results of serum proteins albumin and RBP. In post-vaccine cohorts, the results showed the same pattern as in pre-vaccine cohorts for serum proteins AGPs, CRP, albumin and TTR. However, TF levels were similar between groups and RBP presented a slight reduction as COVID-19 symptomatology increased. In these cohorts, immunoassay validated proteomics results of serum proteins albumin, TTR and TF. Additionally, immune response to α-Gal in pre-vaccine cohorts varied in predominant immunoglobulin type profile, while post-vaccine groups presented mainly anti-α-Gal protective IgG antibodies. The study identified serum nutritional biomarkers that could potentially predict an accurate prognostic of COVID-19 disease to provide an appropriate nutritional care and guidance in non-vaccinated and vaccinated individuals against SARS-CoV-2. These results highlight the importance of designing personalized nutrition protocols to improve diet along with the application of prebiotics or probiotics for the control of COVID-19 and other infectious diseases.