Team finds genetic link between immune and nerve systems

Sep 19, 2008

DURHAM, N.C. —Duke University Medical Center researchers have discovered genetic links between the nervous system and the immune system in a well-studied worm, and the findings could illuminate new approaches to human therapies.

For some time, researchers have theorized a direct link between the nervous and immune systems, such as stress messages that override the protective effects of antibodies, but the exact connection was unknown.

"This is the first time that a genetic approach has been used to demonstrate that specific neurons in the nervous system are capable of regulating immune response in distant cells," said Alejandro Aballay Ph.D., Assistant Professor in the Duke Department of Molecular Genetics and Microbiology.

They studied a neural circuit in the roundworm Caenorhabditis elegans.

"The study of neural-immune communications is quite challenging in mammals," Aballay said. "The simple, well-characterized nervous system of C. elegans and its recently discovered innate immune system make it a prime system for research. We can study the mechanisms and biological meaning of the cross-talk between the immune and nervous systems, and our studies should set the stage for a new field of research."

Pamela Marino, Ph.D., who oversees molecular immunology grants at the National Institute of General Medical Sciences of the National Institutes of Health, said, "Dr. Aballay has made use of the well defined genetics of the roundworm to reveal evidence of cross talk between the nervous system and the innate immune system. Beyond neuronal regulation of immunity, this work opens the door to understanding how neurons may affect other non-neural processes, such as fat storage and longevity."

The study, published in the Sept. 18 issue of Science, was funded by grants from the Whitehead Scholars Program and the National Institutes of Health.

The research team used two approaches to show the genetic connection between nerve cells and immune-response cells.

They found that NPR-1, a worm cell receptor linked to proteins that are similar to mammalian neuropeptide Y, functions to suppress the activity of specific neurons that block immune responses. They then studied worms with a mutated npr-1 gene that produced an NPR-1 receptor that didn't function. The scientists showed that when the flawed receptor didn't work, the neurons were able to block the immune response and the worms became more susceptible to infection by pathogens.

The three different neurons found to express the receptor NPR-1 are exposed to the body fluids of the roundworm – the equivalent of the bloodstream in humans. Signals from the neurons can travel and communicate with other tissues, such as intestinal tissue, which often directly contacts microbial pathogens, Aballay said.

They also performed a full-genome analysis on roundworms that had altered nerve-cell function because of a mutation in the npr-1 gene. This analysis showed the animals had poorly regulated expression of genes that encode markers of innate immune responses. In particular, they found that most of the immune marker genes were regulated by a P38 MAPK signaling pathway, which is required for immunity in animals from worms to humans.

"The complexity of the network involved in the communication between the neural system and the immune system expands the number of possible targets for therapeutic interventions," Aballay said. "The nervous system alone provides a large number of targets for novel approaches to boost innate immunity against different pathogens."

Source: Duke University Medical Center

Explore further: Growing a blood vessel in a week

add to favorites email to friend print save as pdf

Related Stories

Largest study of sponges sheds new light on animal evolution

Feb 04, 2014

Sponges are an important animal for marine and freshwater ecology and represent a rich animal diversity found throughout the world, from tropical climates to the arctic poles. For evolutionary biologists, they also present ...

Recommended for you

Growing a blood vessel in a week

Oct 24, 2014

The technology for creating new tissues from stem cells has taken a giant leap forward. Three tablespoons of blood are all that is needed to grow a brand new blood vessel in just seven days. This is shown ...

Testing time for stem cells

Oct 24, 2014

DefiniGEN is one of the first commercial opportunities to arise from Cambridge's expertise in stem cell research. Here, we look at some of the fundamental research that enables it to supply liver and pancreatic ...

Team finds key signaling pathway in cause of preeclampsia

Oct 23, 2014

A team of researchers led by a Wayne State University School of Medicine associate professor of obstetrics and gynecology has published findings that provide novel insight into the cause of preeclampsia, the leading cause ...

Rapid test to diagnose severe sepsis

Oct 23, 2014

A new test, developed by University of British Columbia researchers, could help physicians predict within an hour if a patient will develop severe sepsis so they can begin treatment immediately.

User comments : 0