Serum C reactive protein predicts humoral response after BNT162b2 booster administration

Background: We explored here the impact that baseline inflammation on post-vaccine anti-SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) antibodies response after BNT162b2 vaccine booster administration. Materials: and Methods: The population consisted of 78 healthcare workers of Pederzoli Hospital in Peschiera del Garda (Italy), who received a booster dose of BNT162b2 vaccine 8 months after completing homologous primary vaccination cycle. Serum levels of anti-SARS-CoV-2 spike trimeric IgG were measured pre- and post-booster, whilst serum C reactive protein (CRP) was measured on pre-booster samples. Results: : BNT162b2 vaccine booster increased anti-SARS-CoV-2 spike trimeric IgG by nearly 40-fold (median increase, 38-fold; IQR, 20-78 folds). A highly significant correlation was found between pre-booster serum CRP concentration and post-booster anti-SARS-COV-2 spike trimeric RBD IgG antibodies variation (r= 0.36; 95%CI, 0.15-0.54; p=0.001). The median post-booster increase of anti-SARS-COV-2 spike trimeric RBD IgG antibodies was significantly higher in patients with serum CRP >3 mg/L compared to those with serum CRP <3 mg/L (54 vs. 37 folds; p=0.025). Conclusions: : Evidence emerged from this study suggest that baseline CRP values could be used as valuable information for personalizing COVID-19 vaccines booster administration.