Therefore, we further determined the levels of 18 cytokines (IP-10, HGF, IL-7, IL-18, IL-31, MCP-1/CCL2, eotaxin/CCL11, BDNF, LIF, PIGF-1, PDGF-BB, MIP-1α/CCL3, MIP-1 β/CCL4, RANTES/CCL5, SDF-1α, SCF, VEGF-A, and VEGF-D) in the plasma of COVID-19 patients (N = 13), healthy (N = 20), and recovered (N = 5) subjects. This evidence concerns the gene BDNF and COVID-19.