Osaka University researchers find rare immune cells in supercentenarians

Researchers from Osaka University, Kyoto University, and the Riken Institute have identified a unique immunological trait in supercentenarians, individuals living beyond 110 years. A study published in Cell Reports reveals that these individuals possess an exceptionally high proportion of a rare type of immune cell known as CD4 cytotoxic T cells (CD4 CTLs).

While these cells typically make up only about 4% of T cells in individuals aged 70 to 99, that figure rises to approximately 9.6% in centenarians and reaches a median of 17.6% in those aged 110 and older. Unlike standard CD4 cells that primarily regulate immune responses, these specific cells can directly attack and eliminate abnormal, damaged, or potentially cancerous cells.

Analysis suggests these cells do not show signs of exhaustion despite the advanced age of the subjects. Instead, they appear to adapt and multiply, with many being clones of a single original cell, indicating a robust and targeted response to recurring biological threats. While the study does not prove these cells are the direct cause of extreme longevity, they provide a significant clue into how some humans maintain health and avoid age-related diseases like cancer.