Related Experiment Video

Updated: Jan 20, 2026

Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production
08:32

Dissecting Innate Immune Signaling in Viral Evasion of Cytokine Production

Published on: March 2, 2014

10.9K

Microbial Exposure Enhances Immunity to Pathogens Recognized by TLR2 but Increases Susceptibility to Cytokine Storm

Matthew A Huggins1, Frances V Sjaastad2, Mark Pierson1

  • 1Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN, USA.

Cell Reports
|August 15, 2019
PubMed

Insights

Microbial exposures alter immune cell populations and cytokine levels. This altered immune state enhances protection against Listeria monocytogenes but increases susceptibility to sepsis, highlighting a dual impact of microbiome on host defense.

Area of Science:

  • Immunology
  • Microbiology
  • Infectious Disease

Background:

  • Microbial exposures shape an individual's basal immune status.
  • Cohousing specific pathogen-free (SPF) mice with pet store mice induces systemic immune alterations, including increased phagocytes and inflammatory cytokines.

Purpose of the Study:

  • To investigate how altered basal immune states from microbial exposure influence the acute response to systemic infections.
  • To determine the differential impact of microbial exposure on responses to Listeria monocytogenes and polymicrobial sepsis.

Main Methods:

  • Cohousing SPF mice with pet store mice to establish distinct microbial exposures.
  • Challenging cohoused and control mice with virulent Listeria monocytogenes (LM) and polymicrobial sepsis models.
  • Analyzing immune cell populations (TLR2+, TLR4+ phagocytes) and cytokine profiles.

Main Results:

  • Cohoused mice showed enhanced protection against LM infection but increased morbidity and mortality in sepsis.
  • Increased Toll-like receptor 2 (TLR2) and TLR4 expressing phagocytes were observed in cohoused mice.
  • A muted response to TLR2 ligand and an amplified response to TLR4 ligand were noted in cohoused mice.

Conclusions:

  • Microbial exposure can prime the immune system for enhanced responses to certain pathogens like LM.
  • Altered immune states due to microbial exposure can increase susceptibility to severe infections like sepsis, leading to immunopathology.
  • Differential TLR responses mediate distinct outcomes in response to varied microbial challenges.
Keywords:
Listeria monocytogenesToll-like receptorsinfectionmicrobiomephysiological microbial exposurepolymicrobial sepsis

More Related Videos

Developing a Salivary Antibody Multiplex Immunoassay to Measure Human Exposure to Environmental Pathogens09:08

Developing a Salivary Antibody Multiplex Immunoassay to Measure Human Exposure to Environmental Pathogens

Published on: September 12, 2016

9.1K
Test Samples for Optimizing STORM Super-Resolution Microscopy16:52

Test Samples for Optimizing STORM Super-Resolution Microscopy

Published on: September 6, 2013

31.6K

Related Concept Videos

Humoral Immune Responses01:36

Humoral Immune Responses

Overview
83.4K
Immune Response Against Viral Pathogens01:29

Immune Response Against Viral Pathogens

The immune system's response to viral infections is a complex and coordinated process involving natural killer (NK) cells, T cell-mediated responses, and antibody-mediated responses.
NK Cells
NK cells are a crucial part of our innate immune system, acting as the first line of defense against viral infections. These cells can recognize and kill infected cells without prior exposure to the virus, effectively slowing down the spread of infection. Additionally, NK cells produce proinflammatory...
1.8K
Magnetic Susceptibility and Permeability01:31

Magnetic Susceptibility and Permeability

In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
2.3K
What is the Immune System?01:38

What is the Immune System?

Overview
127.0K
Increased Body Temperature01:25

Increased Body Temperature

A body temperature above  38°C  (100.4 °F) is known as fever or pyrexia, and a person with fever is termed 'febrile.' Typically, the hypothalamus, a part of the brain that acts as the body's thermostat, regulates body temperature through a thermoregulatory setpoint. It receives signals from cold and warm thermal receptors throughout the body and adjusts the body's temperature accordingly. Fever occurs when this hypothalamic setpoint is altered, usually in...
6.4K
Increased pulse rate01:17

Increased pulse rate

Tachycardia is a condition marked by an abnormally fast or irregular heart rate, surpassing the typical resting rate. In adults, tachycardia is characterized by a pulse rate ranging from 100 to 180 beats per minute. The increased heart rate can result in inadequate blood flow to various body parts, ultimately diminishing the oxygen supply to organs and tissues.
Many factors can elevate the risk of developing tachycardia. These include advanced age, a family history of arrhythmias, and an...
1.1K