Time-Lapse Imaging of Chick Cardiac Precursor Cells

The chick embryo is easily accessible and has therefore been widely used in developmental biology studies. In particular, the early embryo can be removed from the egg and cultured, which allows real-time observations and imaging. Here, we describe ex vivo electroporation followed by long-term time-lapse microscopy, image capture, and processing. We have applied this approach to characterise the migration route of cardiac progenitor cells (CPCs) in live embryos. The heart is the first organ to function during vertebrate development and it is essential for the continued growth and survival of the embryo. In the chick, cardiac progenitors have been mapped to the anterior and mid-primitive streak at Hamburger–Hamilton stage 3. However, until recently it was not possible to observe cell migration trajectories directly. Furthermore, we used grafting of beads or cell pellets or electroporation of expression plasmids to show that Wnt3a acts as a repulsive signal to guide the movement of cardiac progenitors.