Introduction: Intense immunological dysregulation including immune cell lesions have been characteristically observed in severe cases of Coronavirus Disease-2019 (COVID-19), for which molecular mechanisms are least understood. A study of physiological expressions of SARS-CoV-2 host cell entry related factors in immune system components may help explain molecular mechanisms involved in COVID-19 immunopathology. Materials and Methods: Transcriptomic and proteomic expression metadata for SARS-CoV-2 host cell entry receptor ACE2 and entry associated proteases (TMPRSS2, CTSL, and FURIN) were analysed in silico across immune system components including blood lineage cells. Results: ACE2 was not-detected in any of the studied immune cell components, however, varying transcriptomic and proteomic expressions were observed, for TMPRSS2, CTSL, and FURIN. Conclusions: Non-detectable expressions of SARS-CoV-2 host cell entry receptor ACE2 in immune system components or blood lineage cells indicate it doesn’t mediate immune cell lesions in COVID-19. Alternative mechanisms need to be explored for COVID-19 immuno-pathogenesis.