Editing Shimon Sakaguchi (section)

=== The Birth of Regulatory T Cells ===
While studying autoimmune-prone mice, Sakaguchi discovered that removing a specific subset of T cells triggered uncontrolled inflammation and tissue damage.

He named these cells '''“regulatory T cells” (T-regs)''' because they acted as a '''brake system''' within the immune response. ''(source: Nature)''

Over the next two decades, Sakaguchi and his team meticulously characterized these cells, showing that they express a unique surface marker (CD25) and depend on a crucial transcription factor — later identified as the '''FOXP3 gene''', discovered independently by Brunkow and Ramsdell in 2001.

This collaborative understanding of '''T-regs + FOXP3''' unveiled the core mechanism of '''immune tolerance''', explaining why the immune system normally spares healthy tissue.
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