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 hp
Sign In
Advertise with Us
ZeptoMetrix an Antylia scientific company

Download Mobile App




Unique Barcoding System Tracks Pneumonia-Causing Bacteria as They Infect Blood Stream

By LabMedica International staff writers
Posted on 28 Feb 2025
Print article
Image: The unique barcoding system enables tracking of K. pneumoniae as it moves throughout the body (Photo courtesy of AdobeStock)
Image: The unique barcoding system enables tracking of K. pneumoniae as it moves throughout the body (Photo courtesy of AdobeStock)

Bacteremia, also known as blood poisoning, occurs when bacteria manage to overcome the body's immune defenses. This condition can progress into sepsis, a serious illness that is responsible for over a third of hospital-related deaths each year. While individuals are frequently exposed to bacteria from the environment, they often fight off these infections without experiencing this deadly progression. Scientists are working to understand how bacteria spread throughout the body to cause systemic infections, with the ultimate goal of halting this process before it escalates.

Researchers at U-M Medical School (Ann Arbor, MI, USA) have been investigating this issue, focusing on gram-negative bacteria such as Klebsiella pneumoniae, a common cause of pneumonia-related bacteremia. In their previous studies, they identified three stages in the spread of bacteria: initial infection at a site like the lungs, entry into the bloodstream, and replication while avoiding filtration by the liver and spleen. Traditionally, bacterial infections are analyzed by culturing tissue and counting the resulting bacteria. While it’s easy to measure the initial infection phase by observing how bacteria invade the lungs, and similarly, the third phase by assessing how bacteria survive in the liver and spleen, the transition from the lungs into the bloodstream has been difficult to track.

Using an innovative barcoding system, the researchers labeled bacteria with short DNA sequences in mouse models and employed computer analysis to track the movement of K. pneumoniae throughout the body. They initially hypothesized that the bacteria would replicate in the lungs until they overwhelmed the local immune defenses, eventually spilling into the bloodstream. This type of spread, which they called metastatic dissemination, was observed in some mice. However, they also uncovered an unexpected pattern. About half of the mice showed this metastatic pattern, while the other half exhibited a form of bacterial spread where the bacteria entered the bloodstream on their own without first replicating in large numbers, a process they termed direct dissemination.

The findings, published in Nature Communications, revealed that the metastatic pathway was associated with a more severe infection compared to the direct dissemination route. Moreover, over time, the infection tended to follow the metastatic pattern. The discovery of the direct route suggests that bacteria might be establishing low-level reservoirs in other parts of the body, which could offer new targets for treating blood infections. Additionally, the researchers introduced mutations in both the K. pneumoniae bacteria and the mice, which affected the mode of bacterial dissemination. This hinted that the interaction between the bacteria and the host’s immune system could play a key role in determining the course of the infection.

“The project began with a very basic question—how does bacteria leave the lungs—that we have now provided some insight into, closing a significant gap in our knowledge,” said Michael Bachman, M.D., Ph.D., clinical associate professor of pathology and microbiology and immunology at U-M Medical School.

Gold Member
Pharmacogenetics Panel
VeriDose Core Panel v2.0
Verification Panels for Assay Development & QC
Seroconversion Panels
New
TRAcP 5b Assay
TRAcP 5b (BoneTRAP) Assay
New
Hemoglobin/Haptoglobin Assay
IDK Hemoglobin/Haptoglobin Complex ELISA

Print article

Channels

Clinical Chemistry

view channel
Image: Professor Nicole Strittmatter (left) and first author Wei Chen stand in front of the mass spectrometer with a tissue sample (Photo courtesy of Robert Reich/TUM)

Mass Spectrometry Detects Bacteria Without Time-Consuming Isolation and Multiplication

Speed and accuracy are essential when diagnosing diseases. Traditionally, diagnosing bacterial infections involves the labor-intensive process of isolating pathogens and cultivating bacterial cultures,... Read more

Molecular Diagnostics

view channel
Image: Health Canada has approved SPINEstat, a first-in-class diagnostic blood test for axSpA, as a Class II medical device (Photo courtesy of Augurex)

First-in-Class Diagnostic Blood Test Detects Axial Spondyloarthritis

Axial spondyloarthritis (axSpA) is a chronic inflammatory autoimmune condition that typically affects individuals during their most productive years, with symptoms often emerging before the age of 45.... Read more

Immunology

view channel
Image: The cancer stem cell test can accurately choose more effective treatments (Photo courtesy of University of Cincinnati)

Stem Cell Test Predicts Treatment Outcome for Patients with Platinum-Resistant Ovarian Cancer

Epithelial ovarian cancer frequently responds to chemotherapy initially, but eventually, the tumor develops resistance to the therapy, leading to regrowth. This resistance is partially due to the activation... Read more

Technology

view channel
Image: The new algorithms can help predict which patients have undiagnosed cancer (Photo courtesy of Adobe Stock)

Advanced Predictive Algorithms Identify Patients Having Undiagnosed Cancer

Two newly developed advanced predictive algorithms leverage a person’s health conditions and basic blood test results to accurately predict the likelihood of having an undiagnosed cancer, including ch... Read more

Industry

view channel
Image: The collaboration aims to leverage Oxford Nanopore\'s sequencing platform and Cepheid\'s GeneXpert system to advance the field of sequencing for infectious diseases (Photo courtesy of Cepheid)

Cepheid and Oxford Nanopore Technologies Partner on Advancing Automated Sequencing-Based Solutions

Cepheid (Sunnyvale, CA, USA), a leading molecular diagnostics company, and Oxford Nanopore Technologies (Oxford, UK), the company behind a new generation of sequencing-based molecular analysis technologies,... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.