Competition for Survival Signals Maintains Immune Balance Scarce innate lymphoid cells vie with T cells for a shared source of interleukin-7
July 24, 2017
LA JOLLA, CA July 24, 2017 An international team of scientists have learned that the recently discovered and relatively rare innate lymphoid cells (ILC) can exert measurable control over the survival of the mighty T cells. Led by Charles D. Surh, Director of the Academy of Immunology and Microbiology (AIM) at the Institute for Basic Science, the research drew on crucial discoveries from work started at The Scripps Research Institute (TSRI) and completed at La Jolla Institute for Allergy and Immunology and AIM.
Published this week in the journal Immunity, the new study reveals that as a minority population, the innate lymphoid cells possess a mechanism that enables them to outcompete the majority T cells for interleukin-7 (IL- 7), a shared resource needed for the survival of both. Through such a mechanism, innate lymphoid cells, which are involved in the resistance to pathogens, tissue remodeling and immune disorders, can be maintained in vivo to ensure the cellular and functional diversity of the immune system. These findings are not only of interest to the esoteric field of immune homeostasis, but also to the broad biological community because they reveal an instance of cell-to-cell communication that does not conform to the classical direct model (e.g. cell A expresses a product to influence the behavior of cell B), but rather to a more layered, indirect model (e.g. cell A influences cell B by limiting access to a product expressed by cell C).
IL-7's Mysterious Role in Immune Cell Survival
The study of the immune system has produced many life-saving discoveries, the greatest of which is arguably the concept of immunization and immunological memory. Vaccines protect us by providing specific stimulation of populations of B and T cells that are responsive to the components in the vaccine, thereby ensuring that these select cells are ready and waiting if we encounter the pathogen for which the vaccine was designed to prepare us.
The ingredients of the vaccine are relatively short-lived, and soon the cells that were specifically activated can no longer rely on direct stimulation from the vaccine for growth and survival. However, the protective effects of the vaccine can last for many decades because of a complex system of homeostatic factors that support the survival of the vaccine-specific cells during the period between stimulations by the vaccine and pathogen. The homeostatic survival of B and T cells is not only important after vaccination, but also in old age when production of B and T cells slows and we are heavily reliant on the long-term survival of the cells we created when we were young.
The cytokine IL-7 is the immune system's archetypal homeostatic factor. For T cells in particular, IL-7 is the primary survival signal during homeostasis. Moreover, observations from various human diseases and mouse models demonstrated that the availability of IL-7 was the key determinant of the size and naivet of the resting T cell pool. However, in spite of scientists' knowledge of IL-7's crucial role in dictating T cell homeostasis, it was unclear how the body regulates the availability of IL-7 in order to ensure T cell homeostasis. The question was compounded by the difficulty of measuring IL-7 levels in vivo: traditional methods of detection were woefully inadequate to even detect (let alone quantify) IL-7 in mouse tissues.
A New Contender for IL-7 Emerges
Dr. Chris Martin, a graduate of The Kellogg School of Science and Technology and first author of the study, along with fellow researchers made their initial breakthrough discovery thanks to the Surh Lab's success, cultivated over several decades, in characterizing the spontaneous homeostatic T cell proliferation in lymphopenic (i.e. T cell-depleted) mouse models, which occurs in response to elevated amounts of IL-7. In this new study, the researchers built upon the observation that IL-7 levels were deregulated in mice that cannot express the IL-7 2 receptor (IL-7R) because the gene has been knocked out (IL-7Rko mice).
In normal healthy mice, IL-7 is too scarce to provide the amount of stimulation that is required for T cells to undergo homeostatic proliferation. However, in the absence of IL-7R, IL-7 accumulates to supraphysiogical levels that are sufficient to drive T cell homeostatic proliferation. Using homeostatic proliferation as a method to detect excess IL-7, the group replaced various IL-7R-expressing cell types in IL-7Rko mice and monitored for a return of IL-7 homeostasis.
These experiments demonstrated that IL-7 homeostasis is maintained when IL-7R is expressed by cells of the that arise from stem cells in the bone marrow. This finding was consistent with the pre-existing idea that T cells (themselves of the bone marrow lineage) consume IL-7 and thereby decrease IL-7 availability for other T cells. However, the results clearly indicated that T cells were not the only consumers of IL-7. Martin and his colleagues probed further and identified the recently discovered and ultra-rare innate lymphoid cells as the other major IL- 7-consuming cell type.
To be honest, I was quite surprised that ILC have such an effect in this model, said Dr. Martin. Relative to T cells, there are very few ILC in the tissues we study. So, when we were designing the initial experiments, we weren't optimistic that we would find anything interesting.
The second pivotal set of discoveries were made possible by the unique facilities of the Academy of Immunology and Microbiology in Korea. The state-of-the-art germ-free mouse facility allowed Martin's team to eliminate the contribution of the commensal bacteria, which can induce proliferation in lymphopenic mice
Most recent headlines
11/12/2025
Dalet, a leading provider of cloud-native, end-to-end media workflow solutions, ...
06/12/2025
In a live broadcast from the Reagan National Defense Forum, L3Harris Chair and CEO Christopher Kubasik joined Morgan Brennan on CNBCs Closing Bell: Overtime. Ku...
06/12/2025
FORT LAUDERDALE, Fla. A new survey from Pixitmedia by Datacore revealed a major shift in the Media & Entertainment industry in media archiving, with 85% of resp...
06/12/2025
HACKENSACK, N.J. LiveU has announced that the national public broadcaster Czech Television has completed one of the largest LiveU live production deployments fo...
06/12/2025
NEW YORK The National Academy of Television Arts and Sciences (NATAS) presented the Excellence in Production Technology Emmy Award to NASA+ and Dr. Tom Leight...
05/12/2025
2025 Sports Broadcasting Hall of Fame: Curt Gowdy Jr. - Master Storyteller, Nati...
05/12/2025
SVG Sit-Down: Veritone's Sean King on the Power of Mining Video, Audio DataThe company's Data Refinery offers users total control and governance over da...
05/12/2025
Platinum White Paper: Inside the Nashville Predators' Unified, Flexible, Sca...
05/12/2025
Netflix Reaches Agreement To Acquire Warner Bros. Following Planned WBD SplitThe deal does not include WBDs sports assets like TNT Sports (US, UK, LatAm), Euros...
05/12/2025
FOX Sports Returns to Indianapolis for Primetime Broadcast of Big Ten Championsh...
05/12/2025
SVG Summit 2025 Preview: Digital Engagement & Monetization Workshop Tackles the ...
05/12/2025
Atlanta United Lights Up New Emory Healthcare Studio With First Live Broadcast f...
05/12/2025
As Messi Takes the Pitch, MLS, Apple, NEP Roll Out Largest MLS Cup Production Ev...
05/12/2025
ESPN Enters College Football's Most Intense Month With Elevated Workflows fo...
05/12/2025
It's about that time! Awards season is in full swing, and the Film Independe...
05/12/2025
Every year, Spotify Wrapped offers a personalized look back at the audio that defined your year. It's a snapshot of your listening habits, designed to tell ...
05/12/2025
In 2025, Spotify's EQUAL, GLOW, and RADAR programs celebrated women, LGBTQIA , and emerging artists who turned moments into milestones. From breaking record...
05/12/2025
In our latest blog, we explain how Wi-Fi 7 rollouts can drive consumer loyalty with value-add services such as consumer cybersecurity. We also explore how this ...
05/12/2025
LOS ANGELES Netflix announced it has entered into an agreement to acquire the assets of Warner Bros. for $82.7 billion....
05/12/2025
NEW YORK Nielsens Gracenote has launched Gracenote Content Connect, a new ad platform that provides agencies, brands, supply-side platforms (SSPs) and demand-si...
05/12/2025
NEW YORK In an most important update to the workings of deal-based programmatic advertising, IAB Tech Lab has released version 1.0 of its Deals API for public c...
05/12/2025
NEW YORK Pass the turkey. Pass the stuffing. Pass the cranberry sauce. All are common requests of Americans celebrating Thanksgiving Day with family and f...
05/12/2025
NEW YORK Iris, the new cloud-connected camera control platform, has officially launched with features that turn virtually any PTZ camera into a software-connect...
05/12/2025
HOLLYWOOD, Calif. Netflix announced today that it has entered into an agreement to acquire the assets of Warner Bros. for $82.7 billion....
05/12/2025
NEW YORK Iris, the new cloud-connected camera control platform, has officially launched with features that turn virtually any PTZ camera into a software-connect...
05/12/2025
WASHINGTON The Federal Communications Commission has approved AT&T's $1.02 billion acquisition of spectrum from UScellular in a decision that was issued sho...
05/12/2025
The Best Coldplay Songs: 21 Tracks That Shoot for the Stars From Yellow to Viva La Vida, Fix You to Paradise, this playlist goes back to the start.
December ...
05/12/2025
Zafris Lecture Series Brings Nabil Ayers to Berklee The 32nd annual James G. Zafris Distinguished Lecture series was held on Thursday, November 13, with guest...
05/12/2025
Introducing New Perks to Help You Get Even More from LinkedIn Premium Published on Dec 5, 2025 Categories: Company News, Product News
LinkedIn Corporate Co...
05/12/2025
Friday 5 December 2025
A new Game of Thrones Tale: Official trailer for Sky Exc...
05/12/2025
Back to All News
Don Lee, Lee Jin-uk, and Lalisa Manobal to Star in Netflix Act...
05/12/2025
Tis the season of giving once again and this year we've taken our Give Back Fridays' concept and turned it on its head.
In the autumn we were approach...
05/12/2025
Brayden Gogis doesn't remember a time when he wasn't completely fixated on games in all forms. In preschool, when they asked us to dress up as what we ...
05/12/2025
The Grinch steals the spotlight as the theme for The Late Late Toy Show 2025
Tune in tonight at 9:35pm on RT One and worldwide on RT Player
#LateLateToyShow...
05/12/2025
RT Announces New Presenters of Flagship News Programmes
New RT Six One News co-presenter Tommy Meskill
Sarah McInerney & Justin McCarthy join Morning Ir...
04/12/2025
ToolsOnAir Blackmagic Design HyperDeck Event Presets for just:in mac pro 2025 & ...
04/12/2025
ToolsOnAir AJA Ki Pro Event Presets for just:in mac pro 2025 & just:in linux
More Details:Starting with version 5.5, both just:in mac pro and just:in linux sol...
04/12/2025
Wangu Kanuri from Kenya and Godwin Asediba from Ghana are two of this years finalists for Thomsons Young Journalist of the Year Award. The pair are runners-up i...
04/12/2025
SVG Sit-Down: ProximaVision's Claudio Lisman on Why Tethered Drones Could Be...
04/12/2025
SVG Campus Shot Callers: Imry Halevi, Senior Associate Director of Athletics, Co...
04/12/2025
Platinum White Paper: LiveU Lightweight Sports Production: A Step Change in Spor...
04/12/2025
London to Riyadh: DAZN brings the boxing glamour to new production levels for Be...
04/12/2025
Analysis: Paramount bets on the battering ram' with Champions League play By Callum McCarthy, Editor-at-Large
Tuesday, December 2, 2025 - 10:12
Print ...
04/12/2025
Space City Home Network Launches SCHN DTC App for Astros and RocketsThe Rockets and Astros were previously the lone NBA and MLB teams without a DTC appBy Jason...
04/12/2025
SVG Summit 2025 Preview: Content Workflows Workshop Spotlights Evolution of Spor...
04/12/2025
New Sponsor Spotlight: Geotech's Patrick Wambold On the Unreal Engine Revolu...
04/12/2025
Curt Gowdy Jr. - Master Storyteller, Nationally and RegionallyBy Jason Dachman, Editorial Director, U.S.
Thursday, December 4, 2025 - 1:52 pm
Print This Sto...
04/12/2025
(L-R) Rebecca Lichtenfeld, Mohammadreza Eyni, Sara Khaki, and Judith Helfand att...
04/12/2025
SBS launches Future Frames initiative to support emerging First Nations video ed...
Competition for Survival Signals Maintains Immune Balance Scarce innate lymphoid cells vie with T cells for a shared source of interleukin-7 
