IL6 and pulmonary arterial hypertension: IL-6, a centralinflammatory cytokine produced by vascular and non-vascular cells, isquantitatively associated with PAH outcomes [295], and forced overexpression ofits receptor IL6R causes vascular remodeling in animal models of PH [150].Tocilizumab, a humanized monoclonal antibody targeting IL6R and approved for usein certain diseases such as cytokine release syndrome, has shown efficacy atreversing disease pathology in preclinical models.