Work on organoids that could replace the use of mice in some brain studies has won the UK’s major prize for non-animal methods in biomedical research. The award by the National Centre for the Replacement, Refinement and Reduction of Animals in Research (NC3Rs), sponsored by EARA member GSK, went to Dr Laura Pellegrini (pictured) from the MRC Laboratory of Molecular Biology (see video). The research is a major breakthrough as the MRC team developed brain organoids representative of the choroid plexus - the protective barrier between the blood and the cerebrospinal fluid (CSF), similar to the blood-brain barrier. Currently, rodents but sometimes macaques, are used in preclinical research to establish the ability of drugs to cross the choroid plexus and into the central nervous system. Introducing the human organoids as a screening platform could help to prevent ineffective compounds progressing to further studies. Diseases such as hydrocephalus (fluid in the brain) or choroid plexus cancers are also typically studied using CSF derived from mouse embryos.