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Updated: Oct 14, 2026
Isolation, Processing and Analysis of Murine Gingival Cells
Published on: July 2, 2013
[Effects of a controlled Staphylococcus aureus infection on the renewal of endoalveolar cells]
Abstract:
We have studied, in rats, the influence of the intratracheal injection of 30 X 10(6) Staphylococcus aureus upon the differential count and renewal of the cell populations extracted by pulmonary lavage. In vivo labelling of alveolar macrophages was performed by intratracheal injection of 125I iododeoxyuridine, and the evolution of the labelled population was quantitatively followed up after scheduled sacrifice. Dividing cells were also identified at all times in the lavage population, after incorporation of (3H)-thymidine in vitro and autoradiography. The injection of Staphylococcus aureus induced an acute inflammatory process followed by the migration of polymorphonuclears, lymphocytes and macrophages mainly during the first 24 hours. Later on, no viable bacteria were observed and the cell populations returned to control values. Kinetic parameters were found varying as a function of the cell type. The early increase of macrophages was mainly produced by the migration of monocytes, which exhibited a shorter lifespan in alveolus than did resident macrophages. The inflammatory reaction observed, whilst inducing a considerable modification of the cell distributions, did not significantly modify the lifespan of macrophages located within alveolus before the aggression.
Insights
Staphylococcus aureus infection in rats triggers an acute inflammatory response in the lungs, altering immune cell populations. Resident macrophages maintain their lifespan despite the inflammatory challenge.
Area of Science:
- Pulmonary immunology
- Bacterial infection research
- Cellular kinetics
Context:
- Investigating the lung's immune response to bacterial pathogens.
- Understanding the dynamics of immune cells in the alveoli following infection.
- Utilizing rat models to study host-pathogen interactions.
Purpose:
- To analyze the impact of Staphylococcus aureus on lung lavage cell populations in rats.
- To quantify the renewal and lifespan of alveolar macrophages after bacterial challenge.
- To differentiate the origins and kinetics of immune cell infiltration.
Summary:
- Intratracheal injection of Staphylococcus aureus induced acute lung inflammation with polymorphonuclear, lymphocyte, and macrophage migration within 24 hours.
- In vivo labeling and in vitro studies tracked alveolar macrophage populations and cell division.
- While monocytes contributed to early macrophage increase with shorter lifespans, resident macrophages' longevity remained unaffected.
Impact:
- Provides insights into the transient nature of acute bacterial pneumonia-induced inflammation.
- Differentiates the behavior of newly arrived monocytes versus resident macrophages.
- Highlights the resilience of resident alveolar macrophages to acute Staphylococcus aureus infection.
