Microinjection and Micropipette-Controlled Phagocytosis Methods for Neutrophils

The ability to microinject substances into the cytosol of living neutrophils opens the possibility of manipulating the chemistry within the cell and also of monitoring changes using indicators which otherwise cannot be introduced into the cell. However, neutrophils cannot be microinjected by the conventional glass pipette insertion method. Here we outline two techniques which work well with neutrophils, namely, SLAM (Simple Lipid-Assisted Microinjection) and electromicroinjection. As these methods utilize micropipettes, we also include a simple method which uses a micropipette to deliver a phagocytic stimulus to a specific cell at a defined time, enable detailed study of the phagocytic process from particle contact to particle internalization.