TLR7 and COVID-19: Since TLR7 and IFN‐y signaling are two of the three signaling pathways required for DN2 B‐cell development (Jenks et al, 2018), although the involvement of IL‐21 in the COVID‐19 cytokine storm has yet to be studied, viral infection may provide an environment conducive for the generation of DN2 B cells.