Protein PD-L2 Found to Hide Senescent Cells; Blocking It Restores Their Clearance

U.S. researchers have identified a protein that hides senescent cells from the immune system, preventing their removal. The findings suggest that blocking the protein could potentially improve age-related health problems.

According to Cedars-Sinai Medical Center in the United States on the 12th local time, the research team found that a protein called PD-L2 allows senescent cells to evade detection by the immune system and accumulate in the body. The findings were published in the journal Cell Metabolism.

Senescent cells have been damaged and stopped dividing, but they do not die. Instead, they remain in tissues and release substances that cause inflammation. The accumulation of these cells is known to contribute to age-related diseases.

The research team reported that removing or blocking PD-L2 in mice reduced the number of senescent cells and levels of inflammatory substances. The mice also showed improved glucose handling and stronger grip strength.

Human senescent cells also produced more PD-L2 than young cells, and levels of the protein increased with age in some tissues.

Selim Chav, an assistant professor of medical research at Cedars-Sinai and the study’s first and co-corresponding author, said, “PD-L2 appears to help senescent cells that should normally be cleared by the immune system remain in the body.”

Senior author James Kirkland said, “If we can find a way to block this protein, we may be able to help the immune system eliminate these cells and improve health problems associated with aging.”

The research team plans to further study whether blocking PD-L2 can safely provide health benefits to human patients and what role the protein plays in age-related diseases.