IL7 and COVID-19: The COVID-19 is associated with the stimulation of a cytokine storm that leads to elevation in inflammatory cytokines like interleukin (IL)-6, IL-2, IL-7, granulocyte colony-stimulating factor (GCSF), tumor necrosis factor-α (TNF-α) and monocyte chemoattractant protein 1 (MCP-1) in severely ill COVID-19 patients [124].