Recently, there have been many revelations defining ways that the gut microbiome, immune system, and nervous system interact in health and disease.

The Chiu lab focuses on how microbe-neuron-immune interactions relate to chronic pain and host-pathogen defense. Nociceptor somatosensory neurons are peripheral nerve cells that protect organisms from danger by detecting potentially harmful stimuli to elicit the sensation of pain. The Roman scholar Celsus defined pain as a cardinal sign of inflammation. However, centuries later, the molecular mechanisms of pain during inflammation remain mysterious. Our lab has two areas of investigation:

(1) Microbe interactions with the nervous system in pain and host defense
Pain is a component of pathogenic infections. We have found that bacteria produce pain by directly activating neurons through specific peptides and toxins. We are investigating how specific components of the gut microbiome regulate pain and gut motility. Another outstanding question in our lab is to determine whether pain-sensing neurons suppress the immune response against infection, or if they benefit host defense by driving protective immunity.

(2) Sensory neuron-immune interactions in pain and itch
Nociceptors encode the detection of different sensory modalities including pain and itch sensitivity at the molecular level. These neurons also respond to different types of immune cells. We are defining whether specific types of immune cells and their mediators (cytokines, lipids) contribute to pain or itch during inflammation. Defining these interactions could lead to new ways to treat chronic pain and itch.