Baby One More Time

Herpes simplex virus (HSV) is not a “one and done” disease. It hides in the body, waiting to strike again. This process is known as reactivation – typically associated with periods of stress, illness, or sunburn – and, left untreated, can result in blindness. But what exactly causes this reactivation? The answer: neuronal hyperexcitation. Researchers at the University of Virginia School of Medicine have discovered that the virus hijacks an important immune response: when exposed to prolonged periods of inflammation or stress, the immune system releases interleukin 1 beta (IL-1β), a cytokine present in epithelial cells of the skin and eye and released when those cells are damaged by ultraviolet light. IL-1β increases affected neurons’ excitability, setting the stage for HSV reactivation. Though further studies are needed to fully understand these factors – and establish how they can be used to develop potential therapeutics – the team hope their insights will shed new light on the immune system and, ultimately, help prevent HSV outbreaks.