{"id":743621,"date":"2026-08-20T03:28:20","date_gmt":"2026-08-20T03:28:20","guid":{"rendered":"https:\/\/www.newsbeep.com\/uk\/743621\/"},"modified":"2026-08-20T03:28:20","modified_gmt":"2026-08-20T03:28:20","slug":"people-who-live-past-100-have-a-surprising-abundance-of-cancer-killing-immune-cells-sciencealert","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/uk\/743621\/","title":{"rendered":"People Who Live Past 100 Have a Surprising Abundance of Cancer-Killing Immune Cells : ScienceAlert"},"content":{"rendered":"

Today, the average human lives for about 71 years<\/a>.<\/p>\n

A rare few people will see their 100th birthday, earning the title of centenarian, and even fewer will live past 110.<\/p>\n

We call these folks supercentenarians.<\/p>\n

New research published in Cell Press<\/a> reveals one possible explanation for how these superagers might be dodging the mounting risk of cancer<\/a> and illness as the years progress.<\/p>\n

At around 100 years, a rare form of T helper cells seems to proliferate in these lucky people, expanding and adapting as time marches on.<\/p>\n

“These cells exhibit stepwise differentiation and cytokine plasticity, suggesting adaptive responses to persistent antigens during healthy aging,” the study’s authors write<\/a>.<\/p>\n

\"RareThe new research suggests that special immune cells, which transform from helper T cells into a rare type of killer T cell, could be helping people who live past 100 handle immune threats. (Hashimoto et al., Cell Reports, 2026)<\/p>\n

We all have T helper cells <\/a>(aka CD4 cells) as part of our adaptive immune system.<\/p>\n

There are many different kinds of CD4 cells, some rarer than others. Cytotoxic CD4 T cells (CD4 CTLs), for instance, are usually quite infrequent in the human body. <\/p>\n

These T cells are killers rather than helpers: their job is to patrol the body looking for infected, damaged, or cancerous cells to destroy before further damage is done.<\/p>\n

However, as people age into their 90s and beyond, these usually rare CD4 CTLs seem to become increasingly prolific.<\/p>\n

This statistically significant<\/a> pattern appeared in blood samples from a group of 28 Japanese participants (which, admittedly, is a very small sample size, and with citizens of just one country, not necessarily representative of the global human population).<\/p>\n

In the samples from eight people in their 70s, 80s, and 90s, the median proportion of CD4 CTLs was 4 percent. <\/p>\n

Among the 10 centenarians in the study, the median was 9.6 percent \u2013 and in supercentenarians, it was 17.6 percent.<\/p>\n

\"YouTube frameborder=”0\u2033 allow=”accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share” referrerpolicy=”strict-origin-when-cross-origin” allowfullscreen><\/p>\n

But even in this small sample, there were outliers: one participant who had yet to turn 100 actually had the highest proportion of these cells in their blood.<\/p>\n

These cells were active, showing no signs of exhaustion. <\/p>\n

“Immune aging is not simply a process of decline,” says<\/a> immunologist Kosuke Hashimoto, of the University of Osaka in Japan.<\/p>\n

“The selective expansion of certain T cells suggests that, even in extreme old age, the immune system may continue to adapt to age-related challenges.”<\/p>\n

By examining proteins on the surface of the cells, the researchers found that these CD4 CTLs emerged when helper cells lost the protein CD27<\/a>, and then CD28<\/a>. <\/p>\n

Killer T cells<\/a> are known to clone themselves in response to an immune attack, to form a microscopic army.<\/p>\n

This is exactly what the researchers saw in the older adults’ blood samples. <\/p>\n

\"Subscribe<\/a><\/p>\n

On average, around 33 percent of the CD4 CTLs in their blood were clones of just one original cell.<\/p>\n

In a sample from one centenarian, about half of their CD4 CTLs were copies of the same cell.<\/p>\n

This suggests that past a certain age, the human body is faced with increasing immune threats. An abundance of CD4 CTLs could be helping supercentenarians (at least, those living in Japan) survive them.<\/p>\n

Related: The Blood of Centenarians Reveals 37 Proteins Linked With Slower Aging<\/a><\/p>\n

“As we age, abnormal cells, including senescent and cancerous cells, become more common,” Hashimoto says<\/a>. <\/p>\n

“Our findings suggest that immune adaptation to these changes may contribute to exceptional longevity.”<\/p>\n

The research was published in Cell Press<\/a>. <\/p>\n

This article was fact-checked by Clare Watson<\/a> and edited by Clare Watson<\/a>. While we pride ourselves on our process, we are only human. If you spot a mistake, please let us know<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Today, the average human lives for about 71 years. A rare few people will see their 100th birthday,…\n","protected":false},"author":2,"featured_media":743622,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[10],"tags":[59,102,249,56,54,55],"class_list":["post-743621","post","type-post","status-publish","format-standard","has-post-thumbnail","category-health","tag-gb","tag-health","tag-msft-content","tag-uk","tag-united-kingdom","tag-unitedkingdom"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/743621","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=743621"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/743621\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/743622"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=743621"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=743621"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=743621"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}