dornase alfa /dôr″nās/ , a natural enzyme that depolymerizes DNA molecules. Because as much as 70% of the solid matter of purulent material consists of viscous DNA derived from the nuclei of neutrophils, dornase is used in respiratory therapy of disease such as cystic fibrosis to help break down purulent secretions in the airways. Dornase is produced with recombinant DNA technology in Chinese hamster ovary cells.
