Fig 4. Transfection efficiency in human bronchial epithelia cells—duration of protein production.

Lipoplexes were prepared in OptiMem. A fraction of the complexes was kept apart and used as a non-nebulised control. The rest of the solution was aerosolized for 5 minutes by employing a PARI Boy® Nebulizer and collected. 100 ng of IVT mRNA encoding Metridia luciferase were complexed with Lipofectamine (condition 1–1.2 μl; condition 2–1.8 μl) or DMRIE (condition 1–1.2 μl; condition 2–1.5 μl) and added per well. Nebulised and non-nebulised complexes were incubated with 16HBE cells for 2 h. Luciferase activity in 50 μl of supernatants was assayed every 24 h till the relative light units measured with a luminometer dropped below 100. The media were replaced daily after collecting samples for analysis. Enzyme activity is expressed in relative light units, n = 6.