The researchers report the results of modification applied to DNAse, already used as a treatment to thin mucus. Human DNAse has been modified through the addition of a polyethylene glycol (PEG) chain generating different conjugates, whose activity has been tested. After optimization of the conjugates synthesis and purification, the efficiency of the modified DNAse was measured with in vitro experiments by evaluating their ability to degrade DNA, thin the artificial mucus and maintain functionality in the presence of the actin, that acts as a natural DNAse inhibitor.
Several human DNAases were considered, including commercially available rhDNAse I (Pulmozyme by Roche), in addition to DNAse2b and DNAse1L2. Among the synthesized and characterized PEGhylated DNAses, DNase1L2 showed good fluidifying capacity on mucus and resistance to actin and the conjugate PEG20kDa-DNase is the most promising in reducing the viscosity of artificial mucus.