Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is characterized by a huge range of clinical manifestations. Many pathogenetic pathways and virulence mechanisms are still unknown. Nevertheless, it is known that the host’s immune system plays a key role (Blanco-Melo et al., 2020). Notably, age, comorbidities (e.g. diabetes mellitus, obesity), smoking habits and male sex (Rod et al., 2020; Wu et al., 2020) are the fundamental independent risk factors for death from coronavirus disease-19 (COVID-19) (Zhou et al., 2020).