MicroRNA-155 is a main part of proinflammatory puzzle during severe coronavirus disease 2019 (COVID-19).

Genetic and epigenetic parameters play critical roles in determining the outcomes of the severe acute respiratory syndrome coronavirus type 19 (SARS-CoV-2) infection. MicroRNAs (miRNAs) are an important part of the epigenetic factors that regulate several functions of the immune cells and also viruses. Accordingly, the molecules can regulate expression of the immune cell proteins and virus in the host cells. Among the miRNAs, miRNA-155 (miR-155) is well-studied in patients suffering from severe coronavirus disease 2019 (COVID-19). It has been reported that the SARS-CoV-2 infected patients may be directed to induce a cytokine storm or severe proinflammatory responses. This review article discusses the pathological roles of miR-155 during COVID-19 infection.