4th International Conference on Lymphocyte Engineering, gathered together the world’s innovators in immune-gene therapy in Munich, Germany on 12-14 September 2023. Professor Natalia Marek-Trzonkowska form ICCVS took part in this interesting scientific event. She had great opportunity to refresh friendships and cooperation networks. With Anke Fuchs (Technical University of Dresden) and Marc Martinez- Llordella (Quell Therapeutics)- three members of the “Action to Focus and Accelerate Cell-based Tolerance-inducing Therapies” (COST Action).