# Immune cell research on supercentenarian longevity

> Live situation record from CLSTR: https://clstr.news/situations/immune-cell-research-on-supercentenarian-longevity
> Updated: 2026-08-21T21:12:44.000Z. Sources: 20. Developments: 2.

Researchers from the University of Osaka, Keio University, and RIKEN have identified a specific immunological characteristic in supercentenarians, defined as individuals living beyond 110 years. A study published in ‘Cell Reports’ indicates that these individuals possess a significantly higher proportion of rare immune cells known as CD4 cytotoxic T lymphocytes (CD4 CTLs).

While CD4 cells typically act as coordinators, CD4 CTLs function as hybrid cells capable of directly attacking abnormal or infected cells, such as tumors. Data shows these cells represent approximately 4% of T lymphocytes in the 70–90 age group, rising to 9.6% in those aged 100–109, and reaching roughly 17.6% to 18% in supercentenarians.

Lead author Kosuke Hashimoto noted that this increase is an “active adaptive response” involving clonal expansion rather than a passive result of aging. This suggests the immune system can undergo selective remodeling to maintain defenses against cancer and infections even at extreme ages, as these cells do not show signs of immune exhaustion. This finding challenges traditional views of immune senescence as a simple process of decline, suggesting instead that specific T-cell clones multiply to respond to persistent biological threats.

## Claims

- Researchers from Osaka University identified a mechanism for extreme longevity in supercentenarians. (corroborated by 2 sources)
- Supercentenarians over 110 years old undergo an immune system remodeling that expands specific immune cell networks. (corroborated by 2 sources)
- The presence of CD4 cytotoxic T lymphocytes increases significantly with extreme age. (corroborated by 2 sources)
- CD4 T cells represent a median of 4% in participants aged 70-99, 9.6% in those aged 100-109, and 17.6% in those over 110. (corroborated by 2 sources)
- Superagers are adults over 80 with episodic memory comparable to people aged 50 or 60. (single source)
- A specific type of neuron may be responsible for the cognitive resilience seen in superagers. (single source)

## Timeline

### 2026-08-21: Longevity research explores immune advantages of supercentenarians

As Ethel Caterham celebrates her 117th birthday, scientific studies suggest supercentenarians may possess a unique immunological advantage involving highly functional CD4 cytotoxic T lymphocytes.

4 sources. https://clstr.news/cluster/longevity-research-explores-immune-advantages-of-supercentenarians

### 2026-08-19: Osaka University researchers find immune secret to supercentenarian longevity

A study by Japanese researchers reveals that supercentenarians over 110 possess a unique immune adaptation: a high concentration of CD4 cytotoxic T cells that actively fight cancer and infections.

16 sources. https://clstr.news/cluster/osaka-university-researchers-link-cd4-ctl-cells-to-extreme-longevity

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Cite as: Immune cell research on supercentenarian longevity. CLSTR, https://clstr.news/situations/immune-cell-research-on-supercentenarian-longevity