Alveolar macrophage endosomal-lysosomal system: Potential therapeutic targets for COVID-19

Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19) induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Alveolar macrophage (AM), which is known to play a key role in COVID-19 immunopathogenesis, is likely the first immune system cells to encounter SARS-CoV-2 during infection and thus profoundly shape the outcome of the host-virus interaction. Results of previous studies have suggested that coronavirus replication and progeny virus egress occur via the AM-associated endosomal-lysosomal pathway, which is known to play a vital role in the multiplication of respiratory viruses. In this review, we summarize experimental evidence demonstrating a correlation between the AMs' endosomal-lysosomal system and SARS-CoV-2 replication, then discuss prospects for future development of drugs that alter AMs' endosomal-lysosomal function for use as anti-SARS-CoV-2 agents.