The discoverers of the immune system's 'policemen' win Nobel Prize in Medicine

BarcelonaAmerican researchers Mary E. Brunkow and Fred Ramsdell and Japanese Shimon Sakaguchi have been distinguished with the Nobel Prize in Medicine, awarded this Monday by the Royal Swedish Academy of Sciences, to describe how the immune system regulates itself to prevent us from harming ourselves. Specifically, their work established the concept of peripheral immune tolerance, a mechanism that controls our defenses so that they don't attack us as an external threat. This has allowed us to better understand how the immune system works and has opened the door to the development of new treatments for cancer and autoimmune diseases.

The winners identified for the first time regulatory T cells, which modulate the activity of the body's defenses and inhibit them when necessary, thus protecting the body from autoimmune diseases. They also delved into the mechanisms they use to perform their function. Without these cells, the immune system is "hyperactivated," increasing the risk of chronic inflammation, type 1 diabetes, or hypothyroidism, among other autoimmune diseases, according to Ramon Aleman, head of the immunotherapy group at the Catalan Institute of Oncology (ICO), who spoke to ARA. Sakaguchi, 74, a professor at Osaka University, was the first to isolate regulatory T cells and describe their role in the immune system. In 1995, the Japanese researcher went against the widespread belief that immune tolerance only developed due to the elimination of potentially harmful immune cells in the thymus (an organ in the lymphatic system), through a process called central tolerance. His research showed that the immune system is more complex and he discovered a previously unknown class of immune cells that protect the body from autoimmune diseases.

Later, in 2001, Americans Brunkow, 64, a researcher at the Institute for Systems Biology in Seattle, and Ramsdell, 64, a scientist at Sonoma Biotherapeutics in San Francisco, discovered why one species of mice was particularly vulnerable to the virus. Specifically, they observed in a study that these mice have a mutation in a gene they called Foxp3 and also showed that mutations in the human equivalent of that gene cause a serious autoimmune disease, IPEX. They ultimately concluded that this gene plays a determining role in the function of regulatory T cells.

Cancer Research

What these researchers achieved 25 years ago, which has now earned them a Nobel Prize, has improved our understanding of cancer and opened the door to new ways of fighting it. María Casanova, a researcher in the Cancer Immunity Group at the Spanish National Cancer Research Centre (CNIO), explains in the Science Media Centre that for many years, oncology research has attempted to modify regulatory T cells because tumors are capable of using them to escape our defenses. "Beyond their usefulness in research into lupus, psoriasis, and other autoimmune diseases, in solid tumors they are of vital importance because their elimination is responsible for immunotherapy being effective again," the expert maintains.

In 2018, the Karolinska Institute in Stockholm awarded the Nobel Prize in Medicine to the American James P. Allison and the Japanese Tasuku Honjo for their studies on cancer immunotherapy, and this year they are once again recognizing advances in immunology. Brunkow is the fourteenth woman to win the Nobel Prize in medicine since the first one was awarded to German Emil Adolf von Behring in 1901. In 1947, the Swedish jury recognized the first woman, Gerty Cori, alongside two men, but it wasn't until decades later, in 1982, that Barbara McClintock won it alone, without having to share it with any male researcher, something that has never been repeated. In fact, in most of the 116 editions, the prize has been awarded to two or three researchers.