PSMD1 and acute respiratory distress syndrome: Furthermore, a positive correlation between IgG anti-S1 levels and the SpO2/FiO2 ratio was observed in moderate ARDS (R = 0.41, p < 0.05) and severe ARDS non-ICU (R = 0.53, p < 0.01) patients, which indicates a link between antibody response and respiratory function (Fig. 3B, middle left panel); however, no such correlation was found in severe ARDS UCI patients.