Antibody production without animals.

Research always depended on animals or directly on human beings for the generation of antibodies with new specificities. With the opportunity to clone the human antibody repertoire, it is now also feasible to tap the human immune system and to search for new antibody specificities in antibody gene libraries [1, 2]. Phage display technology has fostered these approaches as it allows even rare specificities to be identified in libraries of a complexity of 10(8) to 10(10) [3, 4]. While most of the work in this field is still based on immune libraries, that is, B-cells derived from immunised animals or human individuals, more recent approaches allow even the necessity for immunisation to be by-passed. Synthetic antibody libraries exist of a complexity comparable to the natural immune system of mammals, so that theoretically every imaginable antibody may be detected and then used either for diagnostic or therapeutic purposes [5-7]. Thus, these new gene technology approaches make it possible to generate antibodies completely independently of animals. It may be that animals will only be used in the future to study the immune system of the animal.