The role of different cell types in the different stages of life is an interesting topic of research. In a new study on gene activity in part of the brains of mice, researchers found a high presence of immune cells in older mice. They believe that these rogue immune cells could have some sort of role in the aging process.
Killer T Cells in the Brain
The study was conducted by a team from Stanford University School of Medicine, including Anne Brunet and her colleagues. They set out to look at the subventricular zone of mice brains. This is where new nerve cells are formed. The researchers wanted to get a better understanding of which types of cells are present in that region by using gene activity information. The details of their study are available in Nature.
The researchers found a surprisingly higher presence of killer T cells in the mice brains than might be expected, particularly in older mice compared with younger mice. Killer T cells play a vital role in the body’s immune system. They help to fight pathogens and protect the rest of the body by attacking cells that are infected or damaged. They are not usually expected to be in the brain. Scientists now believe that these fighter cells are up to no good in the brain and may hinder the process of new nerve cell formation by stem cells in the subventricular zone.
This is not the first time that a study has found a relatively high presence of killer T cells in elderly brains. In a previous study involving postmortem human brains, results showed a relative abundance of these immune cells in the brains cells of people in the 79 to 93-year-old bracket compared with those in the 20 to 44-year-old group. All these findings point to the possibility of killer t cell infiltration in the brain having a role in the aging process.