Lupus patients' neutrophils cannot sense bacterial lactate

Researchers at the University of Tennessee have found a problem with how immune cells function in patients with lupus. The study, led by Research Associate Ashley Wise, focused on neutrophils, which are the most common type of immune cell. Neutrophils usually detect infections by sensing substances released by bacteria. In this research, they specifically looked at how neutrophils use mitochondria to sense lactate from bacteria like Staphylococcus aureus. Assistant Professor Andrew Monteith explained that, instead of just being energy producers, the mitochondria in neutrophils help trigger a process called NETosis. This process helps kill bacteria inside the cells. However, in lupus patients, neutrophils have difficulty detecting this lactate because their mitochondria do not function properly. This failure means that these patients are more prone to serious bacterial infections, as their immune response is weakened. The findings were published in the March 12 issue of Cell Host & Microbe. Monteith, who has researched lupus since joining UT in 2023, hopes that these discoveries will lead to better understanding and treatment options for patients. The collaboration with colleagues, including a rheumatologist at UTMC, has been fruitful. Monteith plans to continue researching how neutrophils in lupus patients might contribute to inflammation and how other health issues, like diabetes and obesity, may also be linked to neutrophil function.