Related Experiment Video
Updated: Jun 19, 2026
09:18
Assessing Bacterial Invasion of Cardiac Cells in Culture and Heart Colonization in Infected Mice Using Listeria monocytogenes
Published on: May 27, 2015
PATHOGENIC ORGANISMS OF THE GENUS LISTERELLA
1Department of Animal and Plant Pathology of The Rockefeller Institute for Medical Research, Princeton, N. J.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Researchers identified closely related Gram-positive organisms causing infections in humans and animals. These bacteria trigger a significant monocyte increase and target the heart muscle, leading to necrosis.
Area of Science:
- Veterinary Medicine
- Human Infectious Diseases
- Microbiology
Background:
- Gram-positive organisms have been isolated from various animal diseases, including encephalitis in cattle and sheep, and myocardial infection in fowl.
- Similar organisms have also been linked to meningitis in humans and generalized infections in rabbits.
Purpose of the Study:
- To describe the cultural and serological properties of these closely related Gram-positive organisms.
- To investigate the pathological effects and blood responses following experimental infection with these isolates.
Main Methods:
- Isolation and characterization of Gram-positive organisms from diverse clinical cases.
- In vivo studies involving intravenous injection into chickens, rabbits, and guinea pigs.
- Hematological analysis to observe blood responses, particularly monocyte counts.
- Histopathological examination to determine sites of organism localization and tissue damage.
Main Results:
- Closely related Gram-positive organisms were isolated from meningitis (humans), encephalitis (cattle, sheep), myocardial infection (fowl), and generalized infections (rabbits).
- Intravenous injection into experimental animals induced a marked increase in monocytes.
- The organisms demonstrated a tendency to localize within the myocardium, causing necrosis.
Conclusions:
- A group of related Gram-positive bacteria can cause significant disease across multiple species, including humans and various animals.
- These organisms elicit a distinct hematological response characterized by monocytosis.
- Myocardial localization and subsequent necrosis are key pathological features of infection with these bacteria.
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