Sir Gregory Paul Winter (born 14 April 1951) is a Nobel Prize-winning British biochemist best known for his work on the therapeutic use of monoclonal antibodies. His research career has been based almost entirely at the MRC Laboratory of Molecular Biology and the MRC Centre for Protein Engineering, in Cambridge, England. He is credited with invented techniques to both humanise (1986) and, later, to fully humanise using phage display, antibodies for therapeutic uses. Previously, antibodies had been derived from mice, which made them difficult to use in human therapeutics because the human immune system had anti-mouse reactions to them. For these developments Winter was awarded the 2018 Nobel Prize in Chemistry along with George Smith and Frances Arnold.He is a Fellow of Trinity College, Cambridge and was appointed Master of Trinity College, Cambridge on 2 October 2012. From 2006 to 2011, he was Deputy Director of the Laboratory of Molecular Biology, Medical Research Council, acting Director from 2007 to 2008 and Head of the Division of Protein and Nucleic Acids Chemistry from 1994 to 2006. He was also Deputy Director of the MRC Centre for Protein Engineering from 1990 to its closure in 2010.