Regarding chemokines, the spike-specific IgG/IgM were associated positively with C-X-C motif ligand (CXCL) 5 but negatively with C-C motif ligand (CCL) 4, CXCL9, CXCL10, and CXCL11, which were reportedly upregulated in severe COVID-19 [17]. The gene discussed is CXCL11; the disease is COVID-19.