Animal cell technology is a growing discipline of cell biology which aims not only to understand structures, functions and behaviors of differentiated animal cells but also to uncover their abilities for industrial and medical purposes. The goal of animal cell technology includes clonal expansion of differentiated cells with useful abilities, optimization of their culture conditions on the industrial scale, modulation of their ability in order efficiently to produce medically and pharmaceutically important proteins, and application of animal cells to gene therapy and formation of artificial organs. This Volume gives the readers a complete review of the present state of the art in Japan, a country where this field is well advanced, as well as in Asia, Europe and the United States. The Proceedings will be useful for cell biologists, biochemists, molecular biologists, biochemical engineers and those in other disciplines related to animal cell culture, working in academic environments as well as in the biotechnology and pharmaceutical industries.