TMPRSS2 and COVID-19: The distribution throughout the host body cells of SARS-CoV-2 receptors, angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2), immune-evasive and immuno-regulative viral properties are responsible for the organ-specific manifestations of COVID-19, proliferation and progression of the disease.