Aim: To establish a method for optical sections of HepG2 human hepatoblastoma cells with confocal laser scanning microscope (CLSM) and to study the spatial structure of filamentous actin (F-actin) in HepG2 cells.
Methods: HepG2 cells were stained with FITC-phalloidin that specifically binds F-actin, with propidium iodide (PI) to the nucleus, and scanned with a CLSM to generate optically sectioned images. A series of optical sections taken successively at different focal levels in steps of 0.7 microm were reconstructed with the CLSM reconstruction program.
Results: CLSM images showed that the FITC-stained F-actin was abundant microfilament bundles parallel or netted through the whole cell and its processes. Most F-actin microfilaments extended through the cell from one part toward the other or run through the process. Some microfilaments were attached to the plasma membrane, or formed a structural bridge connecting to the neighboring cells.
Conclusion: A method for double labeling HepG2 human hepatoblastoma cells and CLSM imaging F-actin microfilaments and nuclei by image thin optical sections and spatial structure was developed. It provides a very useful way to study the spatial structure of F-actin.