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Measuring Bacterial Load and Immune Responses in Mice Infected with Listeria monocytogenes
Published on: August 9, 2011
In vitro survival of Listeria monocytogenes in human amniotic fluid
C Altieri1, G Maruotti, C Natale
1Alimentar Productions and Preparations Institute, Agricultural Faculty, Foggia, Italy. ippalim.fgagr@isnet.it
Abstract:
A Listeria monocytogenes strain (CA01/93), haemolytic and virulent in mice, was inoculated in 16 samples of sterile human amniotic fluid to study the growth curves and to provide more information about the pathophysiology of the microorganism in pregnancy. A control test for every analysis was performed with an Escherichia coli strain (CN 02/95). Regardless of the amniotic fluid samples were taken at 34th-39th week of gestation, when it expresses maximum ability to inhibit growth of E. coli, the growth curves of L. monocytogenes do not show any bactericidal (only bacteriostatic) activity of the amniotic fluids against the tested strain. This gives an interesting result about the pathogenesis of the infection in pregnancy and about the potential environmental contamination due to long surviving times of the microorganism in-amniotic fluid.
Insights
Human amniotic fluid showed only bacteriostatic, not bactericidal, activity against Listeria monocytogenes. This suggests L. monocytogenes can survive in amniotic fluid, impacting pregnancy infection pathogenesis and environmental contamination potential.
Area of Science:
- Microbiology
- Infectious Diseases
- Obstetrics
Background:
- Listeria monocytogenes is a significant cause of pregnancy-associated infections.
- Understanding the interaction between L. monocytogenes and the intrauterine environment is crucial for managing infections during pregnancy.
Purpose of the Study:
- To investigate the growth kinetics of Listeria monocytogenes in human amniotic fluid.
- To determine the inhibitory activity of human amniotic fluid against L. monocytogenes during different gestational weeks.
Main Methods:
- Inoculation of sterile human amniotic fluid samples with Listeria monocytogenes (CA01/93).
- Monitoring bacterial growth curves over time.
- Control experiments using Escherichia coli (CN 02/95).
Main Results:
- Human amniotic fluid exhibited only bacteriostatic, not bactericidal, effects on Listeria monocytogenes growth.
- This inhibitory effect was observed irrespective of the gestational age (34th-39th week).
- Escherichia coli growth was inhibited by amniotic fluid, confirming its inhibitory capacity.
Conclusions:
- Amniotic fluid does not effectively kill Listeria monocytogenes, allowing for prolonged survival.
- This finding has implications for understanding the pathogenesis of Listeria monocytogenes infection during pregnancy.
- Prolonged survival in amniotic fluid may contribute to environmental contamination and persistent infection.
