The murine limb bud in culture as an in vitro teratogenicity test system

There is widespread interest today in the use of in vitro methods to study normal and abnormal development. The limb is attractive in this context, since much is known about pattern formation during limb development. The murine limb bud culture technique described in this chapter was developed and refined in the 1970s. In this culture system, limb development mimics that in vivo, although the rate is slower. Growth and cartilage differentiation lead to the formation of proximal and distal structures with an "in vivo-like" 3D shape. Today, limb bud cultures are used to study the roles of genes during embryogenesis and the mechanisms by which chemicals interfere with critical signaling pathways. In this system, uniform developmental stages are selected for assessment, exposures are controlled precisely, and the confounding influences of maternal metabolism and transport are avoided.