Reacción a "Nobel Prize in Medicine or Physiology awarded to Mary E. Brunkow, Fred Ramsdell and Shimon Sakaguchi for understanding how the immune system is kept under control without attacking organs"

This news is yet another example of the importance of immunology in medical advances (2018: checkpoint inhibitors; 2023: mRNA vaccines; 2025: peripheral tolerance). The 2025 prize recognizes the importance of immune tolerance mechanisms for the control and homeostasis of the immune response. Just as important as the efficiency of effector mechanisms is the fact that the response has control mechanisms. Peripheral immune tolerance is fundamental to this, which is why they are awarding the prize. And essential to this tolerance are Treg (regulatory T) cells, first described in 1995 by Simon Sakaguchi, who characterized them phenotypically and in vitro with their functions. At the same time, the other award winners advanced the characterization of peripheral tolerance mechanisms around these cells with murine models of the scurfy mouse and the human disease IPEX (immune dysregulation with X-linked polyendocrinopathy).

All of this work has led to a better understanding of the role of immune tolerance mechanisms at the peripheral level, in tissues, and not only in primary lymphoid organs (such as bone marrow and thymus). In fact, these peripheral mechanisms are more important because they occur throughout life in a highly plastic immune response that must be regulated to maintain homeostasis. Failures in these mechanisms induce autoimmune diseases, among others. Furthermore, their induction and manipulation can become an excellent therapeutic tool not only in autoimmune diseases, but also in other immune-mediated diseases and in the field of transplantation.