TNF and pulmonary arterial hypertension: For example, while TNF-α appears to be clearly implicated in the pathogenesis of RV failure, as well as of PAH, antagonizing this cytokine was not convincing with mixed pre-clinical results (Henriques-Coelho et al., 2008; Wang et al., 2013) and it is known to predispose patients to severe infectious complications such as tuberculosis.