Promising use of immune cell-derived exosomes in the treatment of SARS-CoV-2 infections

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is persistently threatening the lives of thousands of individuals globally. It triggers pulmonary oedema, driving to dyspnoea and lung failure. Viral infectivity of coronavirus disease 2019 (COVID-19) is a genuine challenge due to the mutagenic genome and mysterious immune-pathophysiology. Early reports highlighted that extracellular vesicles (exosomes, Exos) work to enhance COVID-19 progression by mediating viral transmission, replication and mutations. Furthermore, recent studies revealed that Exos derived from immune cells play an essential role in the promotion of immune cell exhaustion by transferring regulatory lncRNAs and miRNAs from exhausted cells to the active cells. Fortunately, there are great chances to modulate the immune functions of Exos towards a sustained repression of COVID-19. Engineered Exos hold promising immunotherapeutic opportunities for remodelling cytotoxic T cells’ function. Immune cell-derived Exos may trigger a stable epigenetic repression of viral infectivity, restore functional cytokine-producing T cells and rebalance immune response in severe infections by inducing functional T regulatory cells (Tregs). Researchers from the University of Nizwa introduce a view on the current outcomes of immunopathology, and immunotherapeutic applications of immune cell-derived Exos in COVID-19, besides new perspectives to develop novel patterns of engineered Exos triggering novel anti-SARS-CoV-2 immune responses.

Schematic diagram presents the role of Exos in severe acute
respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission

SARS-CoV-2 particles use furin to induce spike proteins (SPs) cleavage and bind the S1 subunit to the angiotensin-converting enzyme 2 (ACE2) binding unit to mediate cell entry. SARS-CoV-2 begins to replicate after entry, utilizing ribosomes and endoplasmic reticulum to construct virus units. Exos cargo, which includes completed virus units, viral RNA polymerase and uncombined units, is released extracellularly and transmits cargo to healthy cells.