Related Experiment Video
Updated: May 8, 2026
09:40
Teasing Out the Interplay Between Natural Killer Cells and Nociceptor Neurons
Published on: June 30, 2022
Bacteria activate sensory neurons that modulate pain and inflammation
Isaac M Chiu1, Balthasar A Heesters, Nader Ghasemlou
1Kirby Neurobiology Center, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA.
Nature
|August 23, 2013
Summary
Bacteria directly activate pain-sensing neurons, causing pain during infections. This pain sensation is independent of the immune response, revealing a direct nervous system role in host-pathogen interactions.
Area of Science:
- Neuroscience
- Immunology
- Microbiology
Background:
- Nociceptor neurons detect harmful stimuli, initiating pain and defensive behaviors.
- Bacterial infections cause pain through poorly understood mechanisms, often assumed to be immune-mediated.
Purpose of the Study:
- To investigate the direct mechanisms by which bacteria activate nociceptors and induce pain.
- To determine the role of the immune system in bacterial infection-induced pain.
Main Methods:
- Utilized mouse models of Staphylococcus aureus infection.
- Assessed mechanical and thermal hyperalgesia.
- Investigated neuronal activation via calcium imaging and electrophysiology.
- Examined the role of specific bacterial components (N-formylated peptides, α-haemolysin).
- Used genetic ablation of Nav1.8-lineage neurons.
Main Results:
- Bacterial infection-induced pain in mice is independent of TLR2, MyD88, T cells, B cells, neutrophils, and monocytes.
- Pain and hyperalgesia correlated with live bacterial load, not swelling or immune markers.
- Bacteria directly induced calcium flux and action potentials in nociceptors via N-formylated peptides and α-haemolysin.
- Ablation of Nav1.8 neurons reduced pain but increased local immune infiltration and lymphadenopathy.
Conclusions:
- Bacteria directly activate nociceptors, initiating pain during infection.
- Sensory neurons play an unsuspected role in modulating inflammation during host-pathogen interactions.
- Nervous system activation by pathogens is a key component of the host response.
Related Concept Videos
01:44Nociception
Nociception—the ability to feel pain—is essential for an organism’s survival and overall well-being. Noxious stimuli such as piercing pain from a sharp object, heat from an open flame, or contact with corrosive chemicals are first detected by sensory receptors, called nociceptors, located on nerve endings. Nociceptors express ion channels that convert noxious stimuli into electrical signals. When these signals reach the brain via sensory neurons, they are perceived as pain. Thus, pain helps the...
01:20Pain
Pain serves as a critical warning signal that alerts the body to potential or actual harm. When mechanical pressure on the skin is intense, such as from a sharp pinch, the sensation transitions from touch to pain. Similarly, extreme temperatures, like a hot pot handle, convert the sensation of heat into pain. Pain can also result from overstimulation of other senses, such as blinding light, loud noise, or the intense heat from habañero peppers. This ability to sense pain is essential for...
01:25Analgesia and Pain Management
Pain is critical to various clinical pathologies, provoking an urgent need for effective management. Pain, whether acute or chronic, is a complex neurochemical process. Its alleviation depends on the type, with nonopioid analgesics effective for mild to moderate pain, such as musculoskeletal or inflammatory pain, while neuropathic pain responds best to anticonvulsants, tricyclic antidepressants, or serotonin/norepinephrine reuptake inhibitors. For severe acute or chronic pain, opioids may be...
01:27Tactile and Chemical Senses
Tactile senses encompass touch, temperature, and pain, each mediated by specific receptors. Touch receptors detect mechanical energy or pressure against the skin. Sensory fibers from these receptors enter the spinal cord and relay information to the brain stem. Here, most fibers cross over to the opposite side of the brain. The touch information then moves to the thalamus, which projects a map of the body's surface onto the somatosensory areas of the parietal lobes in the cerebral cortex. This...
01:28Inflammatory Response
An inflammatory response is a localized, nonspecific immune reaction that occurs when a tissue is injured. It is characterized by redness, swelling, heat, and pain, which are commonly called the cardinal signs and symptoms of inflammation. Inflammation can sometimes result in a loss of function.
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
01:38Inflammation
Overview