Immune cell clearance of senescent cells not only improves blood sugar, but also extends the life span of terminally ill mice!

At present, aging is an inevitable process for human beings, along with aging comes not only changes in appearance but also health decline - aging is a great threat to health, most diseases are closely related to aging, whether it is cardiovascular disease or cancer, its occurrence and development are inseparable from aging.

The reason why aging has such a significant impact on health is multifaceted. One of them is that with aging the body produces a lot of senescent cells, these senescent cells just occupy the position not to work, but also affect the body's cell survival environment, causing various inflammatory diseases. Of course, under normal circumstances, the body's immune cells can remove senescent cells, but along with aging, the body's immune system will also continue to decline, resulting in the body can not remove immune cells. This is one of the major reasons why the body becomes ill after aging.

So if we rejuvenate the immune cells and clear the senescent cells again, can we help humans overcome some of the diseases brought about by aging? The answer is certainly yes. The latest issue published in Med, a sub-journal of Cell, brings us the achievement of immune cells clearing senescent cells and successfully reversing the many dangers of aging.

In a normal, young, healthy population, the body's immune cells are known to seek out and kill senescent cells, but in the case of aging, the immune cells seem to lose this function. So researchers set out to find immune cells that themselves can kill senescent cells in the human body, and to find other ways to activate them to get the immune cells back into fighting shape.

The researchers eventually zeroed in on one particular type of immune cell: invariant Natural Killer T Cells (iNK cells). We are more familiar with NK cells, but iNK cells have extremely different characteristics from NK cells. iNK cells have 2 main characteristics that have made them a favorite of researchers.

Firstly iNK cells have the same receptors and these receptors are different from those of other immune cells, thus allowing iNK cells to work without activating other immune cells and thus not having a relatively large impact on the overall immunity of the body.

Secondly, iNK cells have a natural negative feedback regulation in the human body, which means that the more active the iNK cells are, the more the human body will naturally suppress them, so when the iNK cells function for some time, they will return to a dormant state under the body's regulation, and thus will not be affected by the long-term activation of iNK cells.

These 2 points make this particular immune cell take up the burden of being awakened and killing senescent cells. To verify the role of iNK in killing senescent cells, the researchers pretreated mice. The results showed that when the iNK cells cleared the senescent cells from the mice, the mice that were obese because of their diet had a significant improvement in their blood glucose function - meaning that clearing senescent cells can help improve blood glucose regulation, and if this study can be validated in clinical research, it may be possible to provide a solution for those who it may be a boon to those who suffer from diabetes because of their diet.

To further study the effect of iNK cells on the body's function by removing senescent cells, researchers have turned their attention to another "terminal" disease that has a higher mortality rate than cancer - pulmonary fibrosis. Patients with pulmonary fibrosis have an average survival of only 2.8 years after diagnosis, and there is currently no optimal treatment.

Surprisingly, when researchers induced pulmonary fibrosis using bleomycin, which causes symptoms in the lungs of mice and then used iNK cells to remove the cells associated with the aging phenotype in the mouse model, the damaged cells in the mice were significantly reduced and the life span of the mice was significantly extended! It can be said that it provides a potential hope for those patients who can only replace their lungs after pulmonary fibrosis.

So for humans, can iNK cells act directly on senescent cells? Simply put, will activate iNK cells preferentially kill senescent cells (rather than normal cells), so researchers obtained peripheral blood cells from healthy people and isolated and cultured them - and found in the experiment that iNK cells preferentially kill senescent cells! This also laid the foundation for this therapy to go further into the clinic.

iNK cells destroy 100% of senescent cells when they are 18 years old

For aging, we still have no good means to curb it, but perhaps we can find the answer we want from the immune system. Similarly, as our understanding of the immune system grows, immunotherapy will be applied not only to cancer, but also to more areas of health, including the treatment of anti-aging, diabetes treatment, pulmonary fibrosis, and more.

What we need to do now is to protect our immune system before aging breaks down our immune cells.