IL17A and acute respiratory distress syndrome: When these same correlation analyses were only conducted in patients with severe ARDS, these correlations remained intact, with particularly strong correlations between the expression of TM9SF1 and IFN-γ (r = 0.821, P < 0.001), TNF-α (r = 0.640, P < 0.001), and IL-17A (r = 0.613, P < 0.001).