Researchers identify key player in the genesis of human intestinal immunity

June 20, 2013

The trillions of harmful bacteria that populate the human gut represent a continuous threat to our health. Proper intestinal immune function creates a protective barrier between us and the extensive microbial ecosystem in our intestines. Now, researchers at the University of North Carolina School of Medicine have identified the structures that serve as the foundation for the development of the human intestinal immune system.

Specialized immune structures in the intestines, referred to as gut-associated lymphoid tissues, or GALT, are critical components of intestinal immune function. When viruses such as HIV or autoimmune disorders such as inflammatory bowel diseases damage the GALT, intestinal immune function is compromised. The millions of people suffering from such diseases would benefit from therapies that repair damaged GALT. Developing such strategies requires a fundamental understanding of human GALT development.

In mice, specialized aggregates of cells called cryptopatches are the site of GALT development. The presence of similar cell aggregates in human intestines has been controversial. The researchers used humanized mice to demonstrate that cryptopatches serve as the foundation for human GALT formation.

To make this discovery, the researchers bioengineered human immune systems into two very closely related that differed only in their ability to develop cryptopatches. Human GALT structures only developed when cryptopatches were present. In mice where human GALT developed, additional studies revealed that the human GALT facilitated intestinal immune function, including the production of antibodies specifically found in the .

"Our model defines a novel aspect of human GALT development and demonstrates the stepwise process of the intestinal ," said Paul Denton, PhD, research instructor at UNC and an author of the study. "We found evidence that cryptopatches likely work the same way in people and mice."

The study confirms the faithful nature by which the human immune system in these human-mouse chimeric animals recapitulates a normal human immune system.

"This represents a significant advance that will facilitate the study of numerous conditions that affect the gastrointestinal tract," said J. Victor Garcia, PhD, professor of medicine and senior author of the study. "The next step," Garcia said, "is to utilize this model to test regenerative therapies to repair damaged human GALT."

The research was supported by the National Institutes of Health. The article appears in the June 20 issue of the open access journal Cell Reports.

Explore further: Innate immune system can kill HIV when a viral gene is deactivated

Related Stories

Recommended for you

How the tuberculosis vaccine may protect against other diseases

December 6, 2016

The tuberculosis vaccine is well known to help protect against other infectious diseases, as well as cancer, but the exact mechanisms have not been clear. A study published December 6 in Cell Reports now shows that the broad-spectrum ...

Protecting babies from eczema with low-cost Vaseline

December 5, 2016

What if it was possible to prevent your child from getting eczema—a costly, inflammatory skin disorder—just by applying something as inexpensive as petroleum jelly every day for the first six months of his or her life?

How do white blood cells move so fast?

November 22, 2016

If you fall and scrape a knee, it's the job of white blood cells called neutrophils to rush to the site of infection and chase down invading bacteria.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.