By: 6 August 2015
Findings identify receptors modulating macrophages response to spinal cord injury

Findings identify receptors modulating macrophage responses to spinal cord injury

“When it comes to spinal cord injury, macrophages are a ‘double-edged sword’, providing both neural repair-promoting properties and pathological functions that destroy neuronal tissue. New research has conducted investigations to explore the mechanisms governing the positive and negative processes that occur in macrophages following spinal cord injury. “We know from previous research that macrophages are versatile, and signals at the injury site can stimulate repair or destruction – or, confusingly, both!” said lead author John Gensel, assistant professor of physiology in the Spinal Cord and Brain Injury Research Center at the University of Kentucky. “But the mechanisms through which these signals stimulate the good and/or bad functions in macrophages are not known.” Gensel teamed up with Phillip Popovich, director of the Center for Brain and Spinal Cord Repair at The Ohio State University to explore the mechanisms governing the positive and negative processes that occur in macrophages following spinal cord injury. Gensel and Popovich looked at more than 50 animals with spinal cord injury to try to identify which macrophage receptors promoted neuronal repair and which directed the destructive process. “On the cellular level, the body’s response to spinal cord injury is similar to the immune response to attacks by bacteria or viruses,” Gensel said. “The functions that macrophages adopt in response to these stimuli were the focus of our study. We found that activating bacterial receptors boosted the macrophage response and limited damage to the spinal cord following injury, while activating fungal receptors actually contributed to pathology.” While this study oversimplifies the complex process by which macrophages promote repair and destruction of neuronal tissues, it nonetheless sheds light on opportunities to modulate macrophage responses after spinal cord injury, potentially reducing – or even reversing – damage and the resulting side-effects. “The implications are exciting: we now can look for treatments targeted to the receptors that jump-start the macrophage’s restorative effects without activating the receptors that modulate the destructive processes in that same cell.”

Source: Eurekalert


Gensel, J.C., Wang, Y., Guan, Z., et al. (2015) Toll-like receptors and Dectin-1, a C-type lectin receptor, trigger divergent functions in CNS macrophages. J. Neurosci. 35(27), 9966–9976. doi: 10.1523/JNEUROSCI.0337-15.2015