Montreal Heart Institute Research Centre 2 articles published in JoVE Biology Determination of the Relative Cell Surface and Total Expression of Recombinant Ion Channels Using Flow Cytometry Benoîte Bourdin1, Emilie Segura1, Marie-Philippe Tétreault1, Sylvie Lesage2, Lucie Parent1 1Département de Physiologie Moléculaire et Intégrative, Montreal Heart Institute Research Centre, 2Département de Microbiologie, Infectiologie, Immunologie, Centre de recherche de l'Hôpital Maisonneuve-Rosemont Inherited cardiac arrhythmias are often caused by mutations that alter the surface delivery of one or more ion channels. Here, we adapt flow cytometry assays to provide a quantification of the relative total and cell surface protein expression of recombinant ion channels expressed in tsA-201 cells. Bioengineering Permeabilization of Adhered Cells Using an Inert Gas Jet Scott Cooper1, Paul Jonak1, Guillaume Chouinard-Pelletier1, Sylvain Coulombe1, Elizabeth Jones1, Richard L. Leask1,2 1Chemical Engineering, McGill University, 2Montreal Heart Institute This protocol describes a method for the temporary permeabilization of adherent cells using an inert gas jet. This technique facilitates the transfer of genetic material and biomolecules into adherent mammalian cells by the utilization of mechanical forces to disrupt the plasma membrane.