RESUMEN
Objective:To study the mechanisms of neutrophil elastase (NE) induced expression of respiratory mucin MUC5AC. Methods:Using gene recombination techniques,four luciferase reporter gene plasmids containing different length of human MUC5AC gene promoter were constructed.Site-directed mutagenesis technique was used to establish mutants of Sp-l and NF-?B site in MUC5AC gene promoter; the relative luciferase activities were detected in the transfected human pulmonary A549 cells. Results:Series of luciferase reporter gene containing different sequences of human MUC5AC promotor were constructed successfully.NE could increase the expression of luciferase reporter gene plasmid containing -1300bp,-689bp and-324bp version of MUC5AC promoter in the transfected A549 cells (P