NOV 03, 2016 06:54 PM PDT

Dendritic Cells Prevent Friendly Fire in the Immune System

WRITTEN BY: Kara Marker
An important part of a T cell’s immune journey is learning tolerance, which in the world of immunology means the knowledge to tell a pathogen from a host cell. This is vital for T cells patrolling the bloodstream looking for foreign particles to attack. Too strong of a response and innocent host cells are targeted, but too weak of an attack and not enough of the foreign cells are destroyed. Luckily, another player in the immune system teaches tolerance to the T cell population.
High-Resolution Electron Microscopy Image of a Dendritic Cell. Image credit: Donald Bliss, National Library of Medicine
Dendritic cells are antigen-presenting cells of the immune system that guide T cells in lessons of tolerance. A scientist from St. Louis University is particularly interested in the dendritic cell – T cell relationship, and his newest study led to a better understanding of how one T cell mechanism depends on the right signals from dendritic cells to practice tolerance.

“They are the music directors, telling other lymphocytes such as T cells what to do and how to do it. Their most important role is to govern immune responses,” Daniel Hawiger, MD, PhD, said about dendritic cells. When dendritic cells make a mistake and send the wrong signal, self-reactive T cells wouldn’t have the insight to leave alone the body’s own cells instead of attacking them as if they were foreign pathogens, either diminishing the immune response when an attack is needed or signaling for a battle when there’s nothing to fight.

“Perhaps we can harness these functions and learn to turn the volume up or down, in response to the needs of those with a variety of health concerns, and in particular, autoimmune diseases,” Hawiger said.

Last year, Hawiger published findings after discovering a previously unknown mechanism in T cells that they use to maintain tolerance. Now, he dives deeper into the relationship, learning more about how the newly discovered T cell mechanism depends upon signals from specialized dendritic cells to practice tolerance or attack targeted cells.

Hawiger found that when dendritic cells presented antigens to T cells under conditions whether there was no inflammation or infection, neither immunity or the induction of tolerance occurred. Instead, antigen presentation caused activation of T cells, but only temporarily.

Evidently tolerance can only be induced in T cells when antigens are acquired, antigens are presented to T cells by specially-designed dendritic cells, and those cells produce the right signals recognized by T cells as “tolerance” signals. The mechanism that Hawiger discovered in T cells last year is required for the induction of tolerance in this situation.

 “I hope this new information may help us more precisely regulate the immune response,” Hawiger said. “In the case of an illness like multiple sclerosis, where the immune response is causing damage, we may be able to develop a therapy that will dampen that response.”

The recent St. Louis study was published in the journal Immunity.
 


Source: St. Louis University
 
About the Author
  • I am a scientific journalist and enthusiast, especially in the realm of biomedicine. I am passionate about conveying the truth in scientific phenomena and subsequently improving health and public awareness. Sometimes scientific research needs a translator to effectively communicate the scientific jargon present in significant findings. I plan to be that translating communicator, and I hope to decrease the spread of misrepresented scientific phenomena! Check out my science blog: ScienceKara.com.
You May Also Like
SEP 15, 2019
Immunology
SEP 15, 2019
Measuring Up HIV
A research team that has identified a measurable indicator that could prove instrumental in the fight against HIV...
SEP 15, 2019
Health & Medicine
SEP 15, 2019
Bartonella henselae Infection Implicated in Pediatric Acute-Onset Neuropsychiatric Syndrome
Pediatric acute-onset neuropsychiatric syndrome (PANS) is a term used to describe every cause of acute-onset of obsessive-compulsive disorder including str...
SEP 15, 2019
Health & Medicine
SEP 15, 2019
Toxic Air is Shortening Children's Lifespans
According to the State of Global Air 2019 report, air pollution is currently shortening life expectancy by an average of 20 months worldwide. This means th...
SEP 15, 2019
Cannabis Sciences
SEP 15, 2019
Can you be Allergic to Cannabis?
Pollen allergies are very common. As cannabis flowers produce, it is also possible to be allergic to cannabis. Here's what to look out for....
SEP 15, 2019
Microbiology
SEP 15, 2019
The Right Cocktail of Gut Microbes may Prevent or Reverse Food Allergies
Food allergies are a growing public health concern. New work may help pave the way for a therapeutic that reduces or stops allergies....
SEP 15, 2019
Health & Medicine
SEP 15, 2019
Rare Bone Marrow Manifestation in Sarcoidosis
Sarcoidosis is an inflammatory disease with the hallmark diagnostic feature being non-caseating granulomas--clumps of immune cells including macr...
Loading Comments...