Researcher profile

 

Professor of Immunology Rhodri Ceredig



Introducing Rhodri Ceredig

Professor Rhodri Ceredig joined NUI, Galway as Professor of Immunology at REMEDI in September 2008. He moved to Galway after more than 10 years in France as a scientist with the Institut National de la Sante et de la Recherche Medical (INSERM), working as a full-time research. The position at REMEDI presented itself at an opportune time in his career.

"REMEDI and NUI Galway were looking to strengthen their immunology programme, and I saw an opportunity to put back into the field of immunology what I have been lucky enough to learn over the course of my career."

Ceredig's distinguished career

Ceredig's career spans over three decades, and he has collaborated with some of the very best minds working in immunology.

It didn't start smoothly.  When he was in medical school, Ceredig failed to find the inspiration his fellow students had for becoming a practising doctor. When a personal experience alerted him to our lack of understanding of how normal cells behave, he had found his calling.

He was taught immunology by one of the fathers of modern immunology, Philip Gell, author one of the first textbooks of immunology. At Gell's suggestion, he moved to Australia, where he completed a PhD in immunology at the Walter and Eliza Hall Institute for medical research Melbourne University,within the group of Don Metcalf, one of the fathers of modern experimental haematology. His studies convinced him that the immune system should be viewed as an integral part of hematopoiesis.

From there, it was on to Switzerland for a postdoctoral position with Dr. Rob McDonald, then a young scientist just setting up his first research group. They were one of the first groups to use flow cytometry and sorting to quantitate immune responses in vitro. Then, he was enticed back to the John Curtin School of Medical Research (JCSMR), Canberra, Australia to work with Peter Doherty, joint winner with Rolf Zinkernagel of the 1996 Nobel Prize in Physiology or Medicine for the discovery of how the immune system recognizes virus-infected cells. He ran his own small research group there, and he was also in charge of the flow cytometry facility at JCSMR. He brings with him his expertise in flow cytometry to Galway.

Publications

Ceredig and colleagues with whom he has been collaborating for some time, have just been published in Nature Reviews Immunology.  The hematopoietic system was the first cellular system in which a tissue-specific - cell was identified. That is, the different cell lineages of the hematopoietic system, namely, red cells, platelets, granulocytes and lymphocytes are all derived from a single cell type, called the hematopoietic stem cell (HSC). How the complex program of HSC development is orchestrated is not yet fully understood but has been the subject of intense investigation over the last forty years. Indeed, hematopoiesis has become the paradigm for investigating how mammalian cells chose between different lineage fates. Many models have been proposed to explain hematopoiesis, but none adequately explain recent findings. In particular, most models depict cells undergoing a series of binary choices, much like the branching of a tree.  In the article, Ceredig and his co-authors Dr Geoffrey Brown from the University of Birmingham, England and Prof Ton Rolink from the University of Basel, Switzerland are trying to force a change in the way we think about the way in which hematopoietic stem cells choose their fate. One key proposition is that cells can arrive at a particular destination by multiple routes and that the pathway they take is not necessarily unidirectional. "We hope the article will provoke new experiments that will help us to develop a more precise understanding of blood cell formation". Importantly, understanding how hematopoiesis works is crucial for to the treatment of blood cell disorders, such as leukaemias, and to bone marrow transplantation. Work in the  Regenerative Medicine Institute (REMEDI) at NUI Galway concerns cells of mesenchymal origin, namely fat, muscle, bone and cartilage-forming cells. Again, a mesenchymal - cell (MSC) has been proposed but exactly how MSC develop into the different lineages is unclear. Information gleaned from understanding HSC development may be applicable to MSC.

Collaboration

"Opportunities for scientific collaboration rarely take long to present themselves to new academic members. Not surprisingly, Ceredig has already formed promising collaborative relationships with the Department of Biochemistry. "We have a shared interest in DNA repair, something which lymphocytes do very well because in order to develop, they have to chop and change their DNA." Lymphocytes express receptor molecules encoded for by a gene whose sequence is the result of a complex gene rearrangement process.  Normally, if cells try to cut and rearrange their DNA, they die because this process activates the cell suicide pathway.  However, lymphocytes have acquired a way of surviving this dangerous step thereby rearranging their receptor genes.. DNA is also damaged and cut by irradiation. We have recently identified in mice a particular sub-population of early T cell progenitors that is relatively resistant to the lethal effects of irradiation. We wish to understand why these cells have such properties. If such a cell exists in man, this will be of considerable clinical relevance. Bone marrow transplantation is a frequently-used treatment modality and this is frequently preceded by giving patients large doses of irradiation in order to purge the hematopoietic system of HSC and their descendants The implications of this finding are quite profound because treatments like bone marrow transplantation because if we can identify this cell in man and manipulate its survival and development it could have a number of clinical applications. It's a long way off, but is an example of what can emerge from basic science."

Rhodri Ceredig