The BSI was saddened to learn about the recent death of Professor Nicholas Avrion (Av) Mitchison FRS. He was a pioneering immunologist, valued colleague and mentor to many and made ground-breaking contributions within the field of immunology in understanding the role of T lymphocytes in immunological regulation and tolerance, and by crafting an environment to inspire and educate. He also played an integral role in the launch of the British Society for Immunology as one of our founding members.
His dedication to his field and his fellow scientists has meant that his legacy is felt today, through his practice of immunology, and those he trained and inspired to become the leading immunologists of the day and in the generations to come.
We invited our members, and his colleagues and peers to share their stories and recollections of Professor Mitchison. We have compiled those into this piece to remember and celebrate his life and legacy.
“In the current climate of high-tech big data science, it is difficult to conceive of immunology being performed without monoclonal antibodies, flow cytometry, genomic and proteomic analysis and engineered animal systems. Yet some major discoveries were made without these tools at a time where scientists had to rely upon their intellect and not only on technology to solve problems. This was Av Mitchison’s generation and without modern tools he showed that lymphocytes were the cells that were responsible for graft rejection, that tolerance could be induced with high or low doses of antigen, and he also helped to shape the concept of collaboration between T and B cells.
Many senior immunologists will remember a time where one’s prowess at debate, rather than the extent of data shown, carried the argument about how the immune system worked. This discourse and interaction with other scientists is something that Av cherished and is remembered fondly for by many of his past colleagues.
Imagine a salon (Av’s home) where individuals sat around eating and chatting about science simply for the sheer joy of doing so. This is something we should revive. Many will remember his booming voice and huge presence wherever he went. He wasn’t always serious and with a twinkle in his eye he showed a mischievous streak and used to occasionally tease squeamish individuals in the lab. This is counterbalanced with his extreme generosity to junior scientists; in short, he listened to what they had to say and encouraged rather than criticised.
His passing is a great loss to many to whom he was a role-model, mentor, colleague and friend. I was lucky to meet him when I was a junior postdoc and then interact with him as a colleague over coffee at UCL. Below you will find some reminiscences from individuals who knew him for longer and better than I did; I envy them. Finally, as a final word from myself to Av, thank you for your personal and intellectual generosity, you will be missed but not forgotten.
Foreword by Professor Arne Akbar, former BSI President and Professor of Immunology at University College London
Cultivating a community
During his pioneering career, Av regularly hosted his students and the most established minds in immunology in his own home and lab. Those who studied alongside him fondly recall the impact this environment and the connections made there had on them.
Professor Trevor Owens (University of Southern Denmark) was a postdoc with Av from 1981 to 1984: “My interactions with him included many pleasant and stimulating afternoons and evenings … meeting many wonderful and inspiring people around (his) basement kitchen table.”
Professor Sir Marc Feldmann (University of Oxford) was a PhD student in 1972 when he was offered a position in the ICRF Tumour Immunology Unit at UCL, which Av established. He recalled: “An exhilarating experience, for a PhD student to get taken seriously by a seminar room full of scientists – including Av, who as usual asked penetrating questions. The intellectual vibrancy was really stimulating.”
“Av's qualities extended well beyond science, he was a warm and generous human being … Thus, I was fortunate, like many others to benefit from Av's wisdom, both scientific and personal. Interacting with him changed my life.”
Professor Peter Beverley (Imperial College London) worked with Av for more than twenty years and was a member of the ICRF Tumour Immunology Unit: “Wherever he worked, Av attracted brilliant people to work alongside him or pass through the lab, so that those of us working with him knew every important immunologist.”
Professor Edward A Clark (University of Washington), student, colleague and friend of Av for over thirty years recalled: “I asked Av what he liked best during his long career. He replied without a hitch, ‘talking science with scientists’.”
“I learned from Av to follow Seneca’s dictate that ‘ideas belong to all mankind’ and when in doubt, to share data and plans stemming from them.”
Professor Luis Humberto Fabila-Castillo (Mexican Polytechnic, Instituto Politécnico Nacional, IPN) proudly recalled himself as Av’s first Mexican postdoc student and recollected that: “The experience in the lab was also incredible, especially for all the famous immunologists of the time from all over the world that I met there.”
Professor Nicolas Gascoigne (National University of Singapore), former student of Av’s said: “His great gift to us, his students, was to open our intellectual horizons. He introduced me to so many remarkable people: the grandees of immunology, but also the upcoming stars, and the greats in other fields too.”
Professors Sir David (Imperial College London) and Birgit Lane (A*STAR /Skin Research Institute of Singapore) were grateful they got to know Av well during their PhDs. Professor David Lane recalls the excitement of being his PhD student at UCL: "I remember many fun times, he engaged a lot with the students in the lectures and practicals of his undergraduate immunology lectures at UCL and it was hearing him teach that inspired me to become a scientist."
An enduring legacy
The environment Av fostered wherever he went cultivated a welcome, and excitingly rich intellectual arena for the many young scientists under his tutelage. The below words from his students, colleagues and friends are a testament to the impact Av had within the field of immunology and the respect his guidance and encouragement had to shape the careers of those who studied alongside him.
Professor Beverley said: “He was incredibly generous with his time, his support of colleagues and unlike many modern lab heads never thought of putting his name on papers unless he had really contributed directly to the work. Apart from his contributions to transplantation immunology, mechanisms of tolerance and collaboration of T and B cells, Av will surely be remembered for the stimulus his ideas gave to so many immunologists during his time at NIMR, UCL and later as director of the German Rheumatism Research Centre in Berlin.”
“Just being around him made one realise that this was a man who thought deeply about biology. It was a huge privilege to be exposed to his thinking and certainly influenced everything I did in immunology.”
Professor Lane looked back at his PhD: "He gave me a great project to work on, which was the autoantibody response to the liver antigen “F”. The work was fascinating and we now know that a single amino acid difference is the basis for self tolerance and the selective immunogenicity of the two F antigen alleles in mice. A classic case of T cell rather than B cell tolerance."
The result of Professor Feldmann’s work at the Tumour Immunology Unit, overseen by Av, had ground-breaking consequences in the care and treatment for patients with autoimmune diseases: “While at the TIU, I developed in 1983 new ideas about the mechanism of autoimmunity, and its cytokine dependence, which led to the eventual development of antiTNF therapy for rheumatoid arthritis and many other diseases, a significant medical breakthrough, and standard of care globally for millions.”
“So, I am convinced that, while we never published together, or worked closely together, my debt to Av is considerable: and I think this applies to a large number of other scientists; they were guided, mostly indirectly, by questions, environment and other suggestions to a productive path.”
The longevity and unyielding dedication Av had to his field, his students and the immunologists of the next generation is aptly expressed by Professor Francisco Javier Sánchez-García (Mexican Polytechnic, Instituto Politécnico Nacional, IPN). He was Av’s last postdoc at UCL before his retirement: “To this day and from time to time, Av’s example is listened to by students in my postgraduate course, in the line of: ‘Professor Av Mitchison was Head of Department, Editor-in-Chief of the European Journal of Immunology, served on the editorial board of a number of scientific journals, was the President of the Zoological Society of London, among other duties, and still, he had the time to perform experiments. There is no excuse for not doing some experimental work at any age, no matter how busy we think we are.’”
A great scientist whom we will all miss
We would like to conclude this piece with a few final quotes about Professor Mitchison in celebration of his life and legacy.
Professor Francisco Javier Sánchez-García and Professor Luis Humberto Fabila-Castillo treasure plenty of loving memories, and, to them, Av was “always kind and generous”. In particular, Professor Sánchez-García cherishes a “life-long friendship” which has remained “a life changing experience”.
In the words of Professor Owens, “Av was very generous with his time and ideas, and very good company”.
Professor Gascoigne recalls that, “it was Av that gave me a chance and set me on my way”.
The memories our members, and the peers and colleagues of Professor Mitchison have graciously shared with us showcase not only his skill and innovation as an immunologist, but his great value and kindness as a mentor and friend.
First and foremost, as a scientist, Av cultivated a community of learning which allowed for inspiring and lively discussion to be had. Through this premise he engaged with the brightest minds in his field and those outside of it, encouraging his students and peers to contribute, be inquisitive and learn. The experience of this personal touch and Av’s tendency to allow his students to forge their own paths has left an enduring legacy, shaping ground-breaking research and discoveries. From the recollections compiled in this piece what shines through just as brightly as Av’s pioneering and practical contribution to the future of immunology is his generosity and spirited character which has left many fondly calling upon their cherished memories of a great man. In the words of Professor Feldman, and certainly to many, Av was “a great scientist whom we will all miss”.
For more details about Professor Mitchison's life and career, you can watch a collection of interviews in this YouTube playlist from Web of Stories.
Sign up to attend a symposium to celebrate his life and contributions. 'Ideas in contemporary immunology' will take place on Monday 11 September at University College London. Find out more and book a free ticket here.
You can also read another obituary published in Nature Immunology.