TNF and acute respiratory distress syndrome: ARDS patients randomized to prolonged methylprednisolone treatment, contrary to placebo, demonstrated a sustained reduction in plasma and/or BAL levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6 (1), IL-8, soluble intercellular adhesion molecule-1 (1), procollagen aminoterminal propeptide type I and III (1), indices of alveolar-capillary membrane permeability (BAL albumin, total protein, and percentage neutrophils) (26), and an increase in IL-10 (1), protein C (27), and surfactant (28).