We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
LGC Clinical Diagnostics

Download Mobile App




STAT3 Linked to Interferon-Induced Antiviral Response

By LabMedica International staff writers
Posted on 09 Feb 2017
Print article
Image: The crystal structure of STAT3 bound to DNA (Photo courtesy of Wikimedia Commons).
Image: The crystal structure of STAT3 bound to DNA (Photo courtesy of Wikimedia Commons).
A recent paper reported the discovery of a previously unknown anti-viral role for the STAT3 (signal transducer and activator of transcription 3) protein, which links it to the interferon-alpha (IFN-alpha) immune signaling pathway.

Interferon (IFN)-alpha induces a wide spectrum of anti-viral mediators, via the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. STAT1 and STAT2 have been well characterized and shown to upregulate IFN-stimulated gene (ISG) expression; but while STAT3 is also activated by IFN-alpha, its role in anti-viral ISG induction is unclear.

STAT3 is a member of the STAT protein family, which regulates many aspects of cell growth, survival, and differentiation. Malfunction of this signaling pathway is frequently observed in primary tumors and leads to increased angiogenesis and enhanced tumor survival. Knockout studies have provided evidence that STAT proteins are involved in the development and function of the immune system and play a role in maintaining immune tolerance and tumor surveillance. Constitutive STAT3 activation is associated with various human cancers and commonly suggests poor prognosis. It has anti-apoptotic as well as proliferative effects. Several viruses, including hepatitis C and mumps, reduce cellular STAT3 protein levels, via the promotion of ubiquitin-mediated proteasomal degradation. This viral immune evasion mechanism suggests an undiscovered anti-viral role for STAT3 in IFN-alpha signaling.

To investigate STAT3’s functional involvement in the Type I IFN pathway, investigators at Trinity College Dublin first analyzed its effect on the replication of two viruses, influenza and vaccinia. Viral plaque assays, using mouse wild type embryonic fibroblasts (MEFs) and MEFs that lacked STAT3, revealed that STAT3 was required for the inhibition of influenza and vaccinia replication. Furthermore, blocking STAT3 by short hairpin RNA (shRNA) inhibition also enhanced influenza replication and hindered induction of several, well characterized, anti-viral ISGs.

Senior author Dr. Nigel Stevenson, assistant professor of immunology at Trinity College Dublin, said, "For decades we have known that STAT3 is essential for healthy cell growth, but our new revelation identifies it for the first time as an essential anti-viral component in the interferon signaling pathway. In fact, we found that without STAT3, cells cannot fight the common flu virus or the pox vaccinia virus. We thought that since the interferon signaling pathway enhances the immune response against viruses so effectively, viruses might have evolved means to block it - such a reality would explain why several viruses are so troublesome to defeat."

"Of course a major goal of our ongoing work is to find solutions to the real-world problems faced by the thousands of people who cannot clear certain viruses after they have been infected," said Dr. Stevenson. "This discovery opens the door to new therapeutic options, which, we hope, will be able to help people restore their natural immunity against a host of problematic viruses."

The study was published in the December 17, 2016, online edition of the journal Cellular and Molecular Life Sciences.

Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Specimen Collection & Transport
POCT Fluorescent Immunoassay Analyzer
FIA Go
Gold Member
ADAMTS-13 Protease Activity Test
ATS-13 Activity Assay

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Molecular Diagnostics

view channel
Image: The study showed the blood-based cancer screening test detects 83% of people with colorectal cancer with specificity of 90% (Photo courtesy of Guardant Health)

Blood Test Shows 83% Accuracy for Detecting Colorectal Cancer

Colorectal cancer is the second biggest cause of cancer deaths among adults in the U.S., with forecasts suggesting 53,010 people might die from it in 2024. While fewer older adults are dying from this... Read more

Hematology

view channel
Image: The Gazelle Hb Variant Test (Photo courtesy of Hemex Health)

First Affordable and Rapid Test for Beta Thalassemia Demonstrates 99% Diagnostic Accuracy

Hemoglobin disorders rank as some of the most prevalent monogenic diseases globally. Among various hemoglobin disorders, beta thalassemia, a hereditary blood disorder, affects about 1.5% of the world's... Read more

Microbiology

view channel
Image: The new platform is designed to perform blood-based diagnoses of nontuberculosis mycobacteria (Photo courtesy of 123RF)

New Blood Test Cuts Diagnosis Time for Nontuberculous Mycobacteria Infections from Months to Hours

Breathing in nontuberculous mycobacteria (NTM) is a common experience for many people. These bacteria are present in water systems, soil, and dust all over the world and usually don't cause any problems.... Read more

Industry

view channel
Image: These new assays are being developed for use on the recently introduced DxI 9000 Immunoassay Analyzer (Photo courtesy of Beckman Coulter)

Beckman Coulter and Fujirebio Expand Partnership on Neurodegenerative Disease Diagnostics

Beckman Coulter Diagnostics (Brea, CA, USA) and Fujirebio Diagnostics (Tokyo, Japan) have expanded their partnership focused on the development, manufacturing and clinical adoption of neurodegenerative... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.