TNF and acute respiratory distress syndrome: Indeed, intravenous and intratracheal injection of blood EVs from lipopolysaccharide (LPS)-treated rats to naïve rats induces ARDS [16] LPS-treatment causes a significant increase in myeloperoxidase, tumor necrosis factor alpha (TNF-α), interleukin-1β, in both bronchoalveolar lavage (BAL) fluid as well as plasma of naïve rats [16].