Margaret Thatcher, as Prime Minister, criticised Milstein and the MRC’s failure to apply for a patent. Whilst it was the scientific potential of the discovery that interested him most, Milstein also wanted to see the commercial and clinical potential realised. He was extremely loyal to the Medical Research Council and had submitted the manuscript for commercial consideration. He felt that the criticism was groundless and that he had been let down by “the bureaucracy”. (At that time the National Research Development Corporation had a monopoly over MRC inventions.) Notwithstanding the many subsequent honours and public recognition of his service, he hoped that one day a correct account of this history would be written.Monoclonal antibodies have revolutionised the way in which biologists view living systems.

Used as research tools, they allow biological systems to be analysed and dissected with exquisite specificity But they have become much more than research reagents. In hospital laboratories and in home pregnancy kits, for example, monoclonals are used as diagnostics to measure blood levels of hormones and proteins. Labelled with radio-isotopes, monoclonals can image and localise cancers and, coupled to drugs or isotopes, they can be used as “magic bullets” to deliver a lethal dose specifically to cancer cells. Herceptin, recently recommended for the treatment of breast cancer in the NHS, is a monoclonal antibody; other monoclonals are used to treat rheumatoid arthritis and to prevent viral infections.That invention became one cornerstone of the biotechnology industry.

(The other was recombinant DNA technology.) Milstein took a close interest in the development of his invention from laboratory to billion-dollar industry and he helped many biotechnology companies. He also collaborated freely with other scientists on the application of the invention to scientific research and to medicine. But his real interest lay in understanding how the immune system works and in particular how each individual is able to make millions of different antibodies. It was this that had led him to discover monoclonal antibodies and it was to this that he successfully returned in the 1990s when the distractions of the post-Nobel euphoria had subsided.In addition to the Nobel Prize, he was awarded a host of international prizes and honours; he was elected a Fellow of the Royal Society in 1975 and appointed a Companion of Honour in 1995. He was a Fellow of Darwin College, Cambridge, and an Honorary Fellow of Fitzwilliam College, where he had studied as a research student.After “retirement” in 1995, Milstein continued to pursue his research with vigour, publishing more than 25 scientific articles and working in the laboratory until the last. In July 2000 the MRC organised a conference in London to celebrate the 25th anniversary of the discovery of monoclonals.