Neutrophils are specialized immune cells that becomes activated in response to foreign particles or microorganisms. Think of them like security guards in your body. As they travel through the blood, their job is to detect and get rid of invading microorganisms. They also help spark inflammation responses to infections. For these reasons, they are known to help maintain homeostasis in the body, but they can also play roles in disease by increasing inflammation responses if they hang around too long or there are too many of them around. At the end of their life cycle, neutrophils are broken down by a process called apoptosis. When they break down, they release toxic chemicals that can further activate inflammation responses and recruit more neutrophils to the area. The debris left behind when neutrophils are broken down is cleaned up by other immune cells, called macrophages, which triggers an anti-inflammatory response. Delaying the breakdown of neutrophils can therefore change how long immune responses are activated and how big those responses are.
Horses are known to develop a condition called systemic inflammatory response syndrome (SIRS). One of the main reasons this happens is due to issues in the gastrointestinal tract that make it leaky and allow toxic chemicals from bacteria in the gut to get into the circulation. A new study published in the American Journal of Physiology – Lung Cellular and Molecular Physiology, explored ways to prevent the delay in neutrophil breakdown using an anti-inflammatory medication. By supporting the breakdown of neutrophils, the researchers are hoping to help treat diseases that are caused by activation as well as accumulation of these immune cells, such as SIRS in horses.
C Rosales. Neutrophil: A cell with many roles in inflammation or several cell types? Frontiers in Physiology. 9:113, 2018.
SL Anderson, T Duke-Novakovski, AR Robinson, HGG Townsend, B Singh. Depletion of pulmonary intravascular macrophages rescues inflammation-induced delayed neutrophil apoptosis in horses. American Journal of Physiology – Lung Cellular and Molecular Physiology. 320(1): L126-L136, 2021.
Categories: Illnesses and Injuries