Highly efficient transfection of human THP-1 macrophages by nucleofection.

Macrophages, as key players of the innate immune response, are at the focus of research dealing with tissue homeostasis or various pathologies. Transfection with siRNA and plasmid DNA is an efficient tool for studying their function, but transfection of macrophages is not a trivial matter. Although many different approaches for transfection of eukaryotic cells are available, only few allow reliable and efficient transfection of macrophages, but reduced cell vitality and severely altered cell behavior like diminished capability for differentiation or polarization are frequently observed.

Reduced PMA enhances the responsiveness of transfected THP-1 macrophages to polarizing stimuli.

Macrophages are versatile cells of the immune system which react to various external stimuli through different polarization patterns which adjust the cells to the required function whether it is removal of pathogens or necrotic cells, tissue repair or propagation of inflammation. As much of macrophage behavior is determined by their polarization, appropriate models to study macrophage polarization are required. Previously we have published a protocol for transfection of THP-1 macrophages, which in brief pre-differentiates THP-1 monocytes for 48h using 100ng/ml PMA, followed by detachment of the cells and eletroporation using Lonza nucleofector technology and finally includes further 48h of differentiation with 100ng/ml PMA.

Transduction of proteins into leishmania tarentolae by formation of non-covalent complexes with cell-penetrating peptides.

Cell-penetrating peptides (CPPs) are used to transport peptides, proteins, different types of ribonucleic acids (or mimics of these molecules), and DNA into live cells, both plant and mammalian. Leishmania belongs to the class of protozoa having, in comparison to mammalian cells, a different lipid composition of the membrane, proteoglycans on the surface, and signal pathways. We investigated the uptake of two different and easily detectable proteins into the non-pathogenic strain Leishmania tarentolae.