Anne M. Stevens, MD, PhD, Seattle Children’s Hospital

"PDLI as a Marker of Disease Activity in Pediatric SLE"

2008 Michael Jon Barlin Pediatric Lupus Research Program

The immune system must turn on and off quickly to fight infections, then avoid tissue damage from inflammation. One immune system self control mechanism is to make proteins on the surfaces of white blood cells (WBC) that inhibit other WBC when they are no longer needed. One of these proteins, Programmed Cell Death Ligand-1 (PD-L1), is not made by patients with active lupus. Treated patients, with quiet lupus, can make and express the protein on the cell surface again. An in-clinic PD-L 1 test could warn of disease flare. Medications could mimic PD-L1, replacing the inhibitory activity necessary to control inflammation.