TMPRSS2 and COVID-19: Abbreviations: ACE2: Angiotensin-converting enzyme 2; COVID-19: coronavirus disease 2019; CRP: C-reactive protein; ESR: erythrocyte sedimentation rate; HIV: human immunodeficiency virus; IRB, Institutional Review Board; ISH, in situ hybridisation; RT-PCR: reverse transcriptase-PCR; SARS-CoV-2, severe acute respiratory syndrome coronavirus-2; TMPRSS2: transmembrane protease, serine 2; WBC: white blood cell