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
PURITAN MEDICAL

Download Mobile App




Activating the Innate Immune System Cures Rotavirus Infection in Mouse Model

By LabMedica International staff writers
Posted on 24 Nov 2014
Print article
Image: Transmission electron micrograph of multiple rotavirus particles in the feces of an infected child. Each one is about 70 nanometers in diameter (Photo courtesy of Wikimedia Commons).
Image: Transmission electron micrograph of multiple rotavirus particles in the feces of an infected child. Each one is about 70 nanometers in diameter (Photo courtesy of Wikimedia Commons).
Stimulation of the innate immune system, either indirectly with bacterial flagellin or directly with interleukins IL-18 and IL-22, cured Rotavirus infection in a mouse model of the disease.

Investigators at Georgia State University (Atlanta, USA) initially treated Rotavirus infected mice with flagellin, which binds to toll-like receptor 5 (TLR5).

Toll-like receptors (TLRs) are a class of proteins that play a key role in the innate immune system. They are single, membrane-spanning, noncatalytic receptors usually expressed in sentinel cells such as macrophages and dendritic cells, that recognize structurally conserved molecules derived from microbes. Once these microbes have breached physical barriers such as the skin or intestinal tract mucosa, they are recognized by TLRs, which activate immune cell responses. TLR5 recognizes flagellin, the protein monomer that makes up the filament of bacterial flagella, which is found on nearly all motile bacteria. There are highly conserved regions in the flagellin protein among all bacteria, facilitating the recognition of flagellin by a germ-line encoded receptor such as TLR5.

The investigators reported in the November 14, 2014, issue of the journal Science that administration of flagellin to Rotavirus-infected mice induced activation of TLR5 on the animals' dendritic cells, which elicited production of the cytokine interleukin-22 (IL-22). Then, IL-22 induced a protective gene expression program in intestinal epithelial cells. IL-22 is a member of a group of cytokines called the IL-10 superfamily, a class of potent mediators of cellular inflammatory responses. IL-22 is produced by activated DC and T cells and initiates innate immune responses against bacterial pathogens especially in epithelial cells such as respiratory and gut epithelial cells.

Flagellin also induced NOD-like receptor C4 (NLRC4)-dependent production of IL-18 in the infected animals. IL-18 is a cytokine that belongs to the IL-1 superfamily and is produced by macrophages and other cells. IL-18 works by binding to the interleukin-18 receptor, and together with IL-12 it induces cell-mediated immunity following infection with microbial products like lipopolysaccharide (LPS). After stimulation with IL-18, natural killer (NK) cells and certain T-cells release interferon-gamma (IFN-gamma) or type II interferon that plays an important role in activating the macrophages or other cells. In the current study, administration of IL-18 led to immediate elimination of Rotavirus-infected cells.

"What we have done is to broadly activate the innate immune system in a manner that will likely impede a wide range of viruses,” said senior author Dr. Andrew Gewirtz, professor of biology at Georgia State University. “We have described a completely novel way to combat a viral infection by use of a bacterial-derived activator of the immune system. It is analogous to equipping an NFL defense with baseball bats. Blatant violation of all the rules but yet, at least in this case, very effective."

Related Links:

Georgia State University


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
One Step HbA1c Measuring System
GREENCARE A1c
Anti-Cyclic Citrullinated Peptide Test
GPP-100 Anti-CCP Kit
New
Gold Member
Plasma Control
Plasma Control Level 1

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 cobas Malaria test is the first FDA-approved molecular test to screen U.S. blood donors for malaria (Photo courtesy of Roche)

First FDA-Approved Molecular Test to Screen Blood Donors for Malaria Could Improve Patient Safety

Malaria, a serious illness that often leads to death, is spread by a specific mosquito species that infect humans with a parasite. Other transmission modes include blood transfusions, organ transplants,... Read more

Hematology

view channel
Image: The low-cost portable device rapidly identifies chemotherapy patients at risk of sepsis (Photo courtesy of 52North Health)

POC Finger-Prick Blood Test Determines Risk of Neutropenic Sepsis in Patients Undergoing Chemotherapy

Neutropenia, a decrease in neutrophils (a type of white blood cell crucial for fighting infections), is a frequent side effect of certain cancer treatments. This condition elevates the risk of infections,... Read more

Pathology

view channel
Image: The medical office procedure detects the key biomarker in Parkinson’s and related neurodegenerative diseases (Photo courtesy of BIDMC)

Simple Skin Biopsy Test Detects Parkinson’s and Related Neurodegenerative Diseases

Parkinson's disease and a group of related neurodegenerative disorders known as synucleinopathies impact millions globally. These conditions, including Parkinson’s disease (PD), dementia with Lewy bodies... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.