Elucidating the mechanism of T cell depletion is expected to improve cancer immunotherapy

  In the latest research report published in the international journal “Immunity”, scientists at Emory University studied the “depleted” immune cells caused by chronic viral infections to provide information on how to improve cancer immunotherapy information. we. New clue; in this article, the researchers studied depleted CD8 T cells in mice. When viral infection or cancer persists, CD8 T cells will lose the ability to fight the disease and appear on its surface. Inhibitory checkpoint proteins (such as PD-1 and PD-1) may be targeted by cancer immunotherapeutics (such as pembrolizumab and nivolumab) to restore their ability to promote CD8 T cell attack and kill infections.

  Currently, these drugs have been approved by the FDA to treat many types of cancer, but some tumors do not respond to them. Studying depleted CD8 T cells may help you understand how to use your immune system to fight cancer. Chronic infection. In previous studies, researchers found that the depleted cells are not exactly the same, and the diversity of the depleted T cell pool may help explain the variability of the body's response to cancer immunotherapy. Find. In particular, the researchers observed that a kind of stem cell-like cells can continue to proliferate in response to PD-1 blocking drugs, while the more differentiated depleted cell population remains inactive. These stem cell-like cells can maintain depleted T cells. It can be grouped, but it cannot kill virus-infected cells or tumor cells. In this article, the researchers describe the transition phase between stem cell-like cells and truly depleted cells. The truly depleted cells are labeled with the CD101 molecule, cannot migrate to the site of infection, and have low levels. A special protein that can kill infected cells and tumor cells. Researcher Wilhudson said that transitional cells are not completely depleted, they can proliferate and act as cell killers, and they can promote virus control in experiments. Transitional cells lacking CD101 can be an excellent indicator of response to PD-1 blockers. By enhancing the proliferation or survival of these cells or inhibiting their transition to a long-term depleted state, it may help develop effective cancer treatments.

  The results of this article are expected to help researchers develop new strategies to improve cancer immunotherapy. In addition, researchers have systematically identified multiple markers of depleted CD8 T cells that are expected to promote effective resistance activity.