Twenty years of Th17: A dialogue on immunological innovation and translation

In 2005, a new lineage of helper T cells was discovered—Th17 cells—as reported in Nature Immunology , a breakthrough that fundamentally transformed our understanding of immune regulation. This discovery challenged the then-dominant Th1/Th2 paradigm and unveiled an entirely new scenario of immune complexity, particularly in inflammation, host defense, and autoimmunity. Few findings in the past two decades have had such a broad and lasting impact on basic and translational immunology. Th17 has shaped how we understand cytokine networks, immune regulation, and autoimmunity. In October 2025, a dialogue entitled “Twenty Years of Th17: A Dialogue on Immunological Innovation and Translation” was held during the 2025 CSBMB Annual Symposium to commemorate this milestone. Professor Dong reflected on the origins and impact of Th17 research, its integration into the broader immune regulatory network, and his vision for the next two decades.