PROS1 and COVID-19: Shedding of host proteins or SARS‐CoV‐2 S may also contribute to one of the pathological hallmarks in the lungs of COVID‐19 patients, i.e., the abnormal morphology of pneumocytes with frequent multinucleation, indicative of syncytia formation, which is assumed to occur through the fusion of cells expressing the S protein with cells expressing the S receptor ACE2 (Buchrieser et al, 2020; Bussani et al, 2020; Braga et al, 2021).