From the pathophysiological point of view, the spike protein in the morphology of COVID-19 bind to angiotensin-converting enzyme (ACE)-receptors on alveolar epithelial cell type 2 (AT2), primed by transmembrane protease serine 2 (TMPRSS2) to allow coronavirus entry (Marchetti et al., 2018; Li et al., 2019b; Wang et al., 2020b; Vallamkondu et al., 2020). Here, TMPRSS2 is linked to COVID-19.