Navigation Links
Signaling molecule identified as essential for maintaining a balanced immune response
Date:7/22/2011

(MEMPHIS, Tenn. July 22, 2011) St. Jude Children's Research Hospital investigators have identified a signaling molecule that functions like a factory supervisor to ensure that the right mix of specialized T cells is available to fight infections and guard against autoimmune disease.

The research also showed the molecule, phosphatase MKP-1, is an important regulator of immune balance. Working in laboratory cell lines and mice with specially engineered immune systems, scientists demonstrated that MKP-1 serves as a bridge between the innate immune response that is the body's first line of defense against infection and the more specialized adaptive immune response that follows. The results are published in the July 22 print edition of the scientific journal Immunity.

The results raise hopes that the MKP-1 pathway will lead to new tools for shaping the immune response, said Hongbo Chi, Ph.D., assistant member of the St. Jude Department of Immunology and the study's senior author. The co-first authors are Gonghua Huang, Ph.D., and Yanyan Wang, Ph.D., both postdoctoral fellows in Chi's laboratory.

The findings provide new details about how dendritic cells regulate the fate of nave or undifferentiated T cells. Dendritic cells are the sentinels of the innate immune response, patrolling the body and ready to respond at the first sign of infection.

Investigators were surprised that a single molecule regulated production of three out of the four major subsets of T cells, which each play different roles. MKP-1 is a negative regulator of the enzyme p38, which is part of the MAP kinase family of enzymes that control pathways involved in cell proliferation, differentiation and death.

Chi and his colleagues demonstrated that MKP-1 works in dendritic cells by altering production of protein messengers known as cytokines. Those cytokines determine which subset of specialized T cells the undifferentiated T cells are fated to become. In this study, scientists showed that MKP1 controls production of the cytokines that yield T helper 1 (Th1), T helper 17 (Th17) and regulatory T (Treg) cells. Th1 cells combat intracellular bacterial and viral infections. Th17 cells fight extracellular bacterial infections and fungi. Treg cells help with immune suppression, protecting against autoimmune diseases.

The study showed that suppression of p38 by MKP-1 promotes production of interleukin 12 (IL-12), which leads to an increase in Th1 cells. Rising IL-12 coincides with a drop in interleukin 6 (IL-6) and a corresponding dip in production of Th17. MKP-1 also inhibited the generation of Treg cells by down-regulating production of a third cytokine, TGF-beta.

Knocking out MKP-1 in mice disrupted production of IL-12 and IL-6 in dendritic cells as well as the anti-bacterial and anti-fungal immune response, researchers reported. MKP-1 deficiency also promoted T-cell driven inflammation in a mouse model of colitis, an inflammatory disease.

"MKP-1 is the first signaling molecule found in dendritic cells to program differentiation of these diverse T- cell subsets," Chi said.

Previous work by other scientists focused on T cell differentiation in response to stimulation by cytokines. "This research fills a gap in our understanding of dendritic cell-mediated control of T-cell lineage choices," Chi said. "T cells do not recognize pathogens directly, but dendritic cells do. T cells need dendritic cells to tell them what to do. In this study, we show that MKP-1 signaling in dendritic cells bridges the innate and adaptive immune responses by regulating cytokine production."


'/>"/>

Contact: Carrie Strehlau
carrie.strehlau@stjude.org
901-595-2295
St. Jude Children's Research Hospital
Source:Eurekalert

Related medicine news :

1. Defective signaling pathway sheds light on cystic fibrosis
2. Arsenic exposure activates an oncogenic signaling pathway; leads to increased cancer risk
3. New Cancer-Fighting Strategy Focuses On Signaling Molecules
4. Different signaling pathways of cholangiocarcinoma
5. A high-fat diet alters crucial aspects of brain dopamine signaling
6. Rheumatoid arthritis signaling protein reverses Alzheimers disease in mouse model
7. UCLA cancer researchers discover new signaling pathway that controls cell development and cancer
8. Researchers discover new signaling pathway linked to inflammatory disease
9. Link between signaling molecules could point way to therapies for epilepsy, stroke, other diseases
10. Researchers discover signaling pathway crucial to acute lung injury
11. Naturally occurring brain signaling chemical may be useful in understanding Parkinsons
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:10/13/2017)... ... 2017 , ... Lori R. Somekh, founder of the Law Office of ... elder law and special needs planning attorneys. “Membership in ElderCounsel helps our office remain ... to network with elder law attorneys nationwide,” said Somekh. , ElderCounsel ...
(Date:10/13/2017)... ... October 13, 2017 , ... Many families have long-term ... long-term care insurance companies have a waiver for care if the client has a ... when the family pays for care, is often waived, so the benefits from their ...
(Date:10/13/2017)... ... ... Ellevate Network, the leading network for professional women, brought together some of ... their inaugural Summit in New York City in June. The event was livestreamed with ... 3 million. To watch the Mobilize Women video, click here . , ...
(Date:10/13/2017)... ... October 13, 2017 , ... Yisrayl Hawkins, Pastor and Overseer at The ... the most popular and least understood books in the Holy Scriptures, Revelation. The Book ... have baffled scholars for centuries. Many have tossed it off as mere rubbish, but ...
(Date:10/13/2017)... ... October 13, 2017 , ... Coveros, ... Development, has been awarded a contract by the Center for Medicare and Medicaid ... to accelerate the enterprise use of Agile methodologies in a consistent and high ...
Breaking Medicine News(10 mins):
(Date:10/4/2017)... 2017  South Korean-based healthcare product Development Company I.M. ... on Kickstarter. The device will educate the user about ... better efficiency compared to the dated and pricey CPR ... efficacy of the compression for a more informed CPR ... to raise $5,000. ...
(Date:10/2/2017)... Mich. , Oct. 2, 2017 Diplomat ... 8th Day Software and Consulting, LLC , and ... 8th Day Software, based in Tennessee ... LLC. 8th Day expands EnvoyHealth,s service offerings for health ... development. "In an ...
(Date:10/2/2017)... 2017 Halo Labs announces the European launch of their ... HORIZON at MIBio 2017 in Cambridge, U.K ... matter in biopharmaceutical samples with unprecedented speed and sensitivity while using ... Backgrounded Membrane Imaging. ... subvisible particle analysis system ...
Breaking Medicine Technology: