MUC5AC and chronic obstructive pulmonary disease: In the differentiated HBECs from COPD patients, as well as in the NCI-H292 cells, we confirmed the inhibitory effect of pannexin channel inhibitor (CBX), non-selective P2R antagonist (suramin) and non-selective P2X7 antagonist (BBG), but not the selective P2X7 antagonist (A438079), on the poly(I:C)-potentiated MUC5AC expression.