JUL 26, 2017 4:12 PM PDT

Immune Cells Compete Against Each Other for Survival

WRITTEN BY: Kara Marker

A study that was initially designed to simply study T cell homeostasis ended up yielding surprising results. A recently discovered cell type, innate lymphoid cells (ILCs), appeared to be better at securing proteins both ILCs and T cells need to survive. This finding is perplexing because while T cells are plentiful in the body, ILCs are extremely rare.

Innate lymphoid cells (ILCs, in gray) outcompete and exert a measurable control on the survival of the abundant T-cells (pink). This is possible because T cells decrease the number of IL-7 receptors (IL-7R, represented as butterfly nets) after binding IL-7, while ILCs do not. Credits: IBS, modified from freepiks.com

The study was a collaboration between the Institute for Basic Science, La Jolla Institute for Allergy and Immunology, and The Scripps Research Institute. Researchers are interested in understanding more about immune cell homeostasis, especially T cells and B cells, due to their vital role in vaccine effectiveness and in keeping the human body health even as it ages.

T cells need to bind a protein called interleukin-7 (IL-7) to survive, and they have an IL-7 receptor on their cell surface just for this purpose. In the past, scientists had trouble studying T cell homeostasis because it is difficult to measure levels of IL-7 in the lab. But in the current study, scientists found a way around this roadblock to study how the body regulates IL-7 production.

Starting with mice lacking any IL-7 receptors, researchers saw IL-7 proteins begin to accumulate in the mice models, since they had nothing to bind. Then, they reintroduced cells with IL-7 receptors and watched how the mice immune systems reacted. This is where they saw that T cells were not the only cell binding IL-7; ILCs were also binding IL-7 and binding it more effectively.

"To be honest, I was quite surprised that ILCs have such an effect in this model," said lead author, Christopher Martin. "Relative to T cells, there are very few ILCs in the tissues we study. So, when we were designing the initial experiments, we weren't optimistic that we would find anything interesting."

Now with ILCs in the picture, we have to wonder: Why isn’t there enough IL-7 for both these cells? Why do they need to compete? While these questions have yet to be answered, the study scientists do know why ILCs are better at binding IL-7. While T cells decrease the number of IL-7 receptors as they start to bind IL-7, ILC’s don’t, and they can continue binding IL-7 at a rate faster than T cells.

Creating healthy levels of both T cells and ILCs is important for fighting pathogens, making vaccines work, and preparing for good health in old age, when natural production of immune cells slowly diminishes. If scientists can understand why these two cell types have to compete for survival, perhaps they can find a way for both to flourish in harmony.

The present study was published in the journal Immunity.

 

Source: Institute for Basic Science

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
NOV 12, 2021
Health & Medicine
T-Cell Signature Distinguishes COVID-19 Immunity from Other Respiratory Infections
NOV 12, 2021
T-Cell Signature Distinguishes COVID-19 Immunity from Other Respiratory Infections
COVID-19 is a highly studied disease. It’s caused the most significant influx of research papers in a single year& ...
DEC 02, 2021
Cancer
A New Method to Enhance Immunotherapy in Mouse Tumors
DEC 02, 2021
A New Method to Enhance Immunotherapy in Mouse Tumors
Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer, accounting for about 90% of pancre ...
DEC 02, 2021
Microbiology
Antibodies Seem to Keep Gut Fungi in Check, Except in Crohn's Patients
DEC 02, 2021
Antibodies Seem to Keep Gut Fungi in Check, Except in Crohn's Patients
The bacteria that live in the gut microbiome have gotten a lot of attention, and for good reason; gut bacteria have been ...
DEC 09, 2021
Immunology
Stopping the Spread of COVID by Chewing Gum?
DEC 09, 2021
Stopping the Spread of COVID by Chewing Gum?
Scientists have developed a special chewing gum that could reduce the risk of spreading SARS-CoV-2. The technology was d ...
DEC 30, 2021
Clinical & Molecular DX
Treating Rheumatoid Arthritis: No More Trial and Error?
DEC 30, 2021
Treating Rheumatoid Arthritis: No More Trial and Error?
  Treating rheumatoid arthritis can be like throwing darts—doctors don’t always hit the bullseye. Trial ...
JAN 20, 2022
Immunology
Researchers Stumble Upon Cancer Drug While Studying Flesh-Eating Bacteria
JAN 20, 2022
Researchers Stumble Upon Cancer Drug While Studying Flesh-Eating Bacteria
  Scientists studying a neglected tropical disease have made a chance discovery—a promising therapeutic targe ...
Loading Comments...