Jacques Zimmer

Being interested in science and medicine since childhood, it was quite “normal” to undergo medical studies, although I progressively realized that being a clinician would not be the right option for me (among other reasons, I attached myself too much to many patients and had problems admitting that we lost them). My switch to science was the logical consequence, but my MD degree allowed me a different, patient-focused view on my research topics. Seeing pictures of skin ulcers and destroyed faces of HLA class I-deficient patients deeply impressed me, and my goal is always translational research with a human perspective, ultimately benefiting the patient. My current research on cancer and on infectious diseases completely fits into this approach. I started my academic career by studying Medicine in Strasbourg, France. Then, I worked for two years at the Emergency Department in Colmar, France. This very demanding job made me progressively realize that I would not become happy as a MD. Fortunately, I had always been interested in Science and had obtained an equivalent to a Bachelors’ degree in Biochemistry in parallel to my MD studies. This diploma allowed me to register for a “Diplôme d’Etudes Approfondies” (the ancestor of the Master) directed by Prof. Jules A. Hoffmann (future Nobel Prize laureate). My practical internship took place at the Blood Transfusion Centre Strasbourg, where I first “encountered” natural killer (NK) cells, in the context of HLA class I deficiency. I continued with a PhD in the same lab and went then as a postdoc to Prof. Werner Held at the high-rated Ludwig Cancer Centre in Lausanne, Switzerland. I was quite successful there and had famous predecessors (Jean-Laurent Casanova, Lorenzo and Alessandro Moretta, Gérard Eberl, etc). In 2003, I was offered a fixed researcher position at the CRP-Santé in Luxembourg (ancestor of the LIH), and I am working there since that time. My focus of interest are still NK cells, in the context of cancer and infectious diseases. In 2019, I was seriously sick and had to undergo heart surgery for a congenital disease. This experience completely shaped my view on things. I am happy to be back and to make further discoveries. − My MD thesis was a retrospective study of 201 cases of immune thrombocytopenic purpura (ITP) and the usefulness of danazol as a treatment for refractory or primary chronic cases. Compared with other approaches, danazol was quite efficient, which others confirmed. Nowadays rituximab and thrombopoietin receptor agonists are considered superior, but danazol has not disappeared from the literature. − In my PhD thesis, I investigated NK cells from transporter associated with antigen processing (TAP)-deficient patients, which were my long-time “specialty”. I described their phenotype and functions in this disease characterized by a very low cell surface expression of HLA class I molecules and contributed to the investigation of further cases. Natural killer cells are hyporesponsive at baseline but auto-aggressive upon activation, and I still do not completely understand why. − During my postdoc time, I worked on mouse NK cells and had a wide variety of transgenic and knock-out models available which brought me to the demonstration of the so-called “cis-trans model” of NK cell education, claiming that NK cell inhibitory receptors interact with their ligands on their own cell membranes and are therefore less available for “trans” interactions, leading to an optimal calibration of reactivity to “missing self”. − In Lausanne, I was involved in the supervision of and assistance to PhD and Master students. Since my return to Luxembourg, I have my group that I manage on my own. I monitored own projects through their lifetime and assisted my group members in writing and managing tasks. − I have guided five PhD students to the successful defence of their thesis (Natacha Ralainirina, Justyna Kmiecik, Aurélie Poli, Marwan Sleiman and Neha D. Patil, in chronological order). Four of them were financed by the FNR and have started nice careers with good publications. Aurélie Poli was hired as a research engineer but performed that well that I recommended her to undertake a PhD thesis. She is currently a scientist in the Oncology Department of the LIH. I am in charge, at the University of Luxembourg, of Immunology classes in the 6th Semester of the Bachelor of Life Sciences. Since September 2022, I am also "Médecin Coordinateur Académique (Coordinating Medical Doctor)" of Hematology-Immunology classes in the 5th Semester of the Bachelor of Medicine at the University of Luxembourg. I have organized two scientific meetings in Luxembourg, always with the support of the FNR (RESCOM). In 2012, it was a meeting about HLA class I and its deficiencies (around 100 participants), and in 2019, I had the honor and pleasure to organize the Meeting of the Society for Natural Immunity which brought together the entire worldwide NK cell research community.