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Encapsulated Enterococcus faecalis: role of encapsulation in persistence in mouse peritoneum in absence of mouse
1Department of Medicine, Mount Sinai Hospital, New York, NY 10029, USA.
Abstract:
Two nonhemolytic, mucoid, encapsulated strains of Enterococcus faecalis lacked lethality for 23 white mice when inoculated (10(9) cells/mL) intraperitoneally. Bacteremia was short lived (2 to 3 days), but peritoneal cultures remained positive for 7 days postinoculation. Although encapsulation did not result in animal lethality, encapsulation may have delayed peritoneal clearance by interference with phagocytosis.
Insights
Encapsulated Enterococcus faecalis strains did not kill mice, despite persistent bacteria. Encapsulation may hinder phagocytosis, delaying bacterial clearance.
Area of Science:
- Microbiology
- Immunology
- Infectious Diseases
Background:
- Enterococcus faecalis is an opportunistic pathogen.
- Bacterial encapsulation is a virulence factor that can evade host immune responses.
Purpose of the Study:
- To investigate the virulence of encapsulated Enterococcus faecalis strains.
- To determine the effect of encapsulation on host immune response and bacterial clearance.
Main Methods:
- Inoculation of mice with encapsulated Enterococcus faecalis strains.
- Monitoring for lethality, bacteremia, and peritoneal bacterial load.
- Assessing the role of encapsulation in phagocytosis and clearance.
Main Results:
- Nonhemolytic, mucoid, encapsulated Enterococcus faecalis strains did not cause lethality in mice.
- Bacteremia was transient (2-3 days), but peritoneal cultures remained positive for 7 days.
- Encapsulation may have impeded phagocytosis, delaying peritoneal clearance.
Conclusions:
- Encapsulation in these Enterococcus faecalis strains did not confer lethality.
- Encapsulation might play a role in delaying bacterial clearance by interfering with phagocytosis.
