CCL20 chemokine and other proinflammatory markers after Ad26.COV2.S vaccination

In highly stressed circumstances, such as COVID-19 pandemic, biomarkers of the vaccine-induced immunity could be especially convenient. The main aim of our study was to determine C-C motif ligand 20 (CCL20) concentration after Ad26.COV2.S vaccination in regard to more common proinflammatory molecules and its correlation with anti-SARS-CoV-2 antibody concentration. Secondly, we investigated inflammatory and immunologic profile differences between patients with and without arterial hypertension.

The study included 84 subjects vaccinated with Ad26.COV2.S vaccine. Concentration of CCL20, interleukin (IL) 6, C-reactive protein (CRP) was investigated before, 7 and 14 days after vaccination and concentration of anti-SARS-CoV-2 IgG antibody 7 and 14 days after vaccination. All the markers were measured by well-established laboratory methods.

There were no statistically significant changes of CCL20 and IL-6 concentration after the vaccination. The obtained results have shown statistically significant differences for CRP (P = 0.006) concentrations between 3 time points and SARS-CoV-2 IgG antibody (P < 0.001) concentrations between 2 time points. CCL20 did not correlate with IL-6, CRP or anti-SARS-CoV-2 IgG antibody concentration. Statistically significant difference for CRP (P = 0.025) concentration between 3 time points was observed in the subgroup of subjects with arterial hypertension.

Although our results did not show changes in CCL20 concentration after the vaccination, possibly due to the study timeframe, further investigations on chemokine profile post SARS-CoV-2 immunization could facilitate the recognition of specific patterns of response (supra- or sub-optimal) to the vaccine.