TLR4 and pulmonary arterial hypertension: Identical genomic approaches in subjects with ARDS and pulmonary hypertension (10–13) identified extracellular nicotinamide phosphoribosyl transferase (eNAMPT) as a damage-associated molecular pattern protein (DAMP) and master regulator of innate immunity pathways via ligation of the Toll-Like receptor 4 (TLR4) and subsequent NF-κB activation (14), processes directly implicated involvement in organ fibrosis (15, 16).