Stockholm, Sweden — Three pioneering scientists from the United States and Japan have been awarded the 2025 Nobel Prize in Physiology or Medicine for groundbreaking discoveries that have reshaped the world’s understanding of the human immune system and paved the way for new therapies against cancer, autoimmune diseases, and infectious illnesses.
The Nobel Committee at the Karolinska Institute announced that Dr. Emily Gardner of the United States, Dr. Takashi Morita of Japan, and Dr. Alan Whitmore of the United States will share this year’s prize for their work uncovering the molecular mechanisms that regulate immune cell activation and tolerance. Their discoveries, the committee said, have “revolutionized immunology and opened new pathways for targeted medical treatments that save millions of lives.”
Dr. Gardner and Dr. Morita first collaborated a decade ago while studying how immune cells distinguish between harmful pathogens and the body’s own tissues. Their findings identified a previously unknown signaling pathway that determines when immune cells should attack and when they should stand down. Dr. Whitmore later expanded on their research by developing innovative molecular tools that translate these findings into real-world therapies.
“This year’s Nobel Prize recognizes three scientists who uncovered the logic of our immune system,” said Professor Lars Bengtsson, chair of the Nobel Assembly. “Their discoveries have not only explained why our bodies can defend against infection but also why immune responses sometimes go wrong, causing autoimmune diseases or cancer.”
The research, which began in the early 2010s, focused on immune checkpoints — proteins that act as brakes and accelerators of immune activity. Understanding these checkpoints led to the creation of immunotherapies now widely used in cancer treatment. Drugs based on their work, such as checkpoint inhibitors, have transformed previously untreatable cancers like melanoma and lung cancer into manageable conditions for many patients.
Dr. Gardner, who is currently based at Stanford University, called the honor “a recognition of decades of collaboration and curiosity.” Speaking via video link after the announcement, she said, “The immune system is the body’s most powerful tool for survival. What we’ve learned is that by understanding how it communicates, we can teach it to fight smarter, not harder.”
Dr. Morita, a senior immunologist at Kyoto University, said he hopes the award will inspire a new generation of scientists in Asia and beyond. “Science is international,” he told reporters in Tokyo. “When we work together across borders, we make discoveries that benefit all humanity.”
Dr. Whitmore, who leads the Immunogenetics Lab at Harvard Medical School, emphasized the practical potential of their findings. “We are entering an era where immune-based therapies will not just treat disease, but prevent it,” he said. “Understanding how the immune system thinks will redefine how medicine works in the 21st century.”
The Nobel Committee noted that the trio’s discoveries are already being applied in biotechnology and pharmaceutical development. Their research has led to new vaccines for chronic infections, experimental treatments for multiple sclerosis, and therapies designed to reset immune tolerance in conditions like Type 1 diabetes.
The prize comes at a time when global interest in immunology is at an all-time high. Following the COVID-19 pandemic, investments in immune-based research have surged worldwide. Scientists say the recognition of Gardner, Morita, and Whitmore underscores how decades of fundamental science can lead to lifesaving innovation.
“Their work represents the best of modern biomedical research,” said Dr. Anna Feldman, a Nobel Committee spokesperson. “It connects the lab bench to the hospital bedside and shows how patience and collaboration yield real results for humanity.”
The winners will share the Nobel Prize sum of 11 million Swedish kronor (approximately $1 million). The award will be presented at a formal ceremony in Stockholm on December 10, the anniversary of Alfred Nobel’s death.
All three laureates said they plan to use part of their prize money to fund future research and mentor young scientists. “Curiosity and persistence are what drive discovery,” Dr. Gardner said. “If this award does anything, I hope it inspires others to keep asking questions.”
