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Laudatio uitgesproken door prof. dr. Elisabeth Hooghe-Peters

Laudatio voor prof. dr. Martin Raff
Uitgesproken door prof. dr. Elisabeth Hooghe-Peters

Excellencies,
Colleagues,
Ladies and Gentlemen,

It will take me very little time to convince you that Martin Raff, from University College London, is an exceptional person and that our University feels most privileged to have had him as a lecturer in 1987 and now to have him as a Doctor Honoris Causa.

Described as one of the world’s most original biologists, Martin Raff has made seminal contributions to almost every area of modern biology, including immunology, neurobiology and developmental biology.
Even if you are not a scientist, you have heard about AIDS patients suffering from consequences of white blood cell depletion. The senior immunologists in the audience, like our rector Dr Van Camp, still remember Raff’s papers in Nature, a leading journal in science, analyzing a brain-thymus antigen, theta, or Thy-1 which became a much used marker for the thymus-derived lymphocytes or T-cells. T-cells are depleted in the blood of AIDS patients and it is therefore right to state that Martin Raff provided a tool for investigating AIDS even before AIDS was recognized as a disease.

There are two kinds of lymphocytes, T cells – that I just mentioned – and B cells. Not only did Martin Raff contribute to the characterization of T cells, he was also involved in the characterization of B cells by showing that B cells, but not T cells carry antibodies at their surface. This too was of critical importance: indeed, cell surface antibodies act as receptor for the antigen. Binding of antigen to the receptor triggers the immune response that protects us against infection but that also can lead to allergic diseases.

Antibodies to Thy-1 or to cell surface antibodies could be made fluorescent. It so became possible to study cell physiology by watching the fate of fluorescent molecules on the surface of living cells. These fluorescent molecules are initially dispersed at random over the cell surface but, within minutes, they will cluster in patches and then move to one pole of the cell demonstrating the fluid nature of the cell membrane. All this has changed our understanding of cell membranes in normal and cancer cells.
The contribution of Martin Raff to immunology would largely justify the award of a Honorary degree.

The antibodies against Thy-1 or against cell surface antibodies could be used to purify cell populations that carry these molecules. Martin Raff next postulated that the same strategy used to characterize blood cells would allow the characterization and purification of other cell types, in particular cells from the nervous system.
Hard work resulted in the identification of several antigens each one specific for a given cell population. With these tools in hand, Martin Raff then studied the differentiation of nerve cells in culture. Oligodendrocyte precursor cells, which give rise to the cells that make myelin in the central nervous system, can proliferate indefinitely in culture and – most importantly – can revert to nervous system stem cells if given the appropriate extracellular signals. Martin Raff identified an intracellular timing mechanism that helps oligodendrocyte precursor cells to stop dividing and differentiate at the appropriate time in development. Obviously, these studies are of critical relevance for our understanding of multiple sclerosis and degenerative diseases of the central nervous system. They also provide a strong basis for studying repair and regeneration in the brain.
More recently, Martin Raff has been studying how cells from the embryo decide whether to survive or die, grow or stop growing, proliferate or stop proliferating, or differentiate into one cell type rather than another. He has found that all of these decisions depend on a combination of cell-cell interactions and cell-intrinsic programs. He showed, for example, that the survival of mammalian cells requires continuous signalling from other cells, without which the cells activate a suicide program and die by apoptosis. His results have increased our understanding of how the size of an organ or an entire animal is determined.
As a cell biologist, or as a neurobiologist, Martin Raff again largely deserves a honorary degree.

From the eighties on, students and teachers of biology are very grateful to Martin Raff for his input into the wonderful textbook Molecular Biology of the Cell. This book has largely contributed to the education of a new generation of scientists. Believe me, one of his great strengths is the clarity he brings to any issue and he is the best person to talk science with, though he will prefer being challenged and arguing about scientific – but also political – issues!
Martin Raff always wanted to bring science into the public eye. This was the reason for writing about science for newspapers and talking about biology in TV shows! Finally, I would like to draw particular attention to the merits of a noble mind. Martin Raff is known for his immense generosity. Colleagues and students agree that he is an exceptionally helpful person. He is committed to the belief that a free exchange of ideas is essential to an active scientific community. He is passionate about science and has always helped people who like to do science. To friends and colleagues, he is known as Magic Martin.
Today, he is passionate about two important problems : autism, on one hand and euthanasia, on the other hand, as he believes that society is barbaric in the way it treats end of life issues by removing the right to die from individuals. Also war is barbaric and from the time of the Vietnam war until now Martin Raff kept demonstrating that he is a peace lover.

Martin Raff is a modest person and will insist, in a somewhat self-deprecatory, Woody Allen-like way, that many of his discoveries were due to sheer luck and to the generosity of colleagues. Indeed, he had some luck. Indeed, he was fortunate to meet people like Av Mitchison and to start his research career in places where exciting research was going on. But today, we feel lucky, and happy, and fortunate to have him here, at Brussels Free University.