The Fraunhofer EMB develops new bioreactors and reactor principles. The common methods for the expansion of adherent cells in bottles or on microcarriers in suspension are limited and achieve maximum multiplication factors of 10-100 per batch. This results in a considerable effort to produce biomedically or industrially relevant quantities of adherently growing cells. The AG relies on an increase of cells in hydrogels, in which cells can grow and proliferate three-dimensionally. The new methodology allows for a cyclical process in which each cycle produces about a ten-fold increase in the amount of cells. This allows very easily expansion factors beyond 105. Device development for such innovative reactor technologies is currently being pursued.