Senescent Cd8 T Effector Memory Cells Are Functionally Impaired, Enriched In Aging And Disease, And A Barrier To Immunotherapy
Our immune system relies on specialized cells to protect us from illness. Among these are CD8 T effector memory cells, which are like the seasoned veterans of our immune defense, remembering past threats and quickly responding to new ones. However, new research reveals a significant challenge: some of these crucial immune cells can become “senescent.”
Senescent cells are often referred to as “zombie cells” because they stop dividing but remain active, releasing substances that can harm surrounding healthy cells. This study found that when CD8 T effector memory cells become senescent, they lose their ability to perform their vital functions. They struggle to multiply, produce important signaling molecules called cytokines, and even fail to eliminate other harmful senescent cells in the body.
These dysfunctional senescent immune cells are not just a random occurrence; they accumulate as we age and are more prevalent in individuals with age-related diseases, cancer, and even in smokers. This accumulation suggests they play a role in the decline of immune function over time and in the progression of various illnesses.
Crucially, the research also highlights that this state of immune cell senescence is different from another known dysfunctional state called “exhaustion,” and it appears to be a dominant factor in limiting the effectiveness of immunotherapies. Immunotherapy is a type of treatment that harnesses the body’s own immune system to fight diseases like cancer. The presence of these senescent immune cells can hinder the success of such treatments.
Understanding these senescent immune cells and their impact opens new avenues for developing strategies to boost our immune system, combat age-related diseases, and improve the efficacy of immunotherapies.
Source: link to paper