Working with Immortalized Hepatic Stellate Cell Lines

Hepatic stellate cells (HSCs) are the major cellular source of extracellular matrix production in the liver. Therefore, this cell population has received considerable attention in studies investigating fundamental features of hepatic fibrosis. However, the limited supply and ever-increasing demand for these cells, combined with the additional tightening of formal standards in animal welfare policy, make working with these primary cells increasingly difficult. Moreover, researchers working in biomedical research are challenged to implement the 3R principle of "replacement," "reduction," and "refinement" in their work. This principle, originally proposed in 1959 by William M. S. Russell and Rex L. Burch, is now widely endorsed by legislators and regulatory bodies in many countries as a roadmap to tackle the ethical dilemma associated with animal experimentation. As such, working with immortalized HSC lines is a good alternative to limit the number of animals and their suffering in biomedical research. This article summarizes issues that need to be considered when working with established HSC cell lines and provides general guidelines for the maintenance and storage of HSC lines from mouse, rat, and humans.