A comprehensive immune profiling on moderate to severe COVID-19 patients suggested an overall increase in innate immune cells (monocytes, neutrophils, and eosinophils) while a reduction in T cell population.88,420 Subsequent functional analysis demonstrated decreased secretion of IFN-γ and elevated secretion of IL-17A, along with increased expression of PD-1, in peripheral γδ T cells of patients. This evidence concerns the gene IFNG and COVID-19.