Specific TLR activation on PASMCs leads to the production of chemokines, such as the X-X-C-motif chemokine ligand 8 (CXCL8 or interleukin (IL)-8) and CXCL10 (IP-10), and endothelin-1, which may participate in PAH pathogenesis [11]. The gene discussed is CXCL8; the disease is pulmonary arterial hypertension.