Transfection of primary leukocytes has traditionally been a challenging but much desired protocol. It allows not only the analysis of cells in a more natural state to a cell line system, it enables the direct comparison of, for e.g. transcriptional activity using luciferase reporters, in immune cells taken from genetically-altered mice. In addition, importantly it allows for "rescue experiments" in knockout cells & the ability to over-express or reconstitute wild-type and/or mutated constructs. - [Read Transfection of Bone Marrow-Derived Mast Cells for Transcription Factor Luciferase Reporter Assays]