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Isolation of Tonsillar Mononuclear Cells to Study Ex Vivo Innate Immune Responses in a Human Mucosal Lymphoid Tissue
07:38

Isolation of Tonsillar Mononuclear Cells to Study Ex Vivo Innate Immune Responses in a Human Mucosal Lymphoid Tissue

Published on: June 14, 2020

Bacterial penetration into tonsillar surface epithelium during infectious mononucleosis

L E Stenfors1, H M Bye, S Räisänen

  • 1Department of Otolaryngology, University of Tromsö, Tromsö, Norway. larseric@fagmed.uit.no

The Journal of Laryngology and Otology
|January 6, 2001
PubMed

Insights

Bacterial penetration into tonsillar epithelial cells was observed in patients with infectious mononucleosis. This suggests bacteria may proliferate inside cells, potentially leading to peritonsillar abscess.

Area of Science:

  • Microbiology
  • Pathology
  • Electron Microscopy

Background:

  • Infectious mononucleosis, caused by Epstein-Barr virus (EBV), can present with tonsillitis.
  • The role of bacterial co-infections in the pathogenesis of EBV-related tonsillar complications is not fully understood.

Purpose of the Study:

  • To investigate bacterial penetration and intracellular proliferation within tonsillar epithelial cells in patients with infectious mononucleosis and membranous tonsillitis.
  • To explore the potential link between bacterial invasion, EBV infection, and the development of peritonsillar abscess.

Main Methods:

  • Transmission electron microscopy (TEM) was used to examine epithelial cells scraped from the palatine tonsils of patients.
  • Samples were obtained from 14 patients diagnosed with infectious mononucleosis and concomitant membranous tonsillitis.

Main Results:

  • Bacteria were observed adhering to and penetrating tonsillar epithelial cells.
  • Some epithelial cells were found to be completely filled with bacteria, indicating intracellular proliferation.
  • Epstein-Barr virus, particularly with co-infection by beta-haemolytic streptococci, appears to facilitate bacterial penetration.

Conclusions:

  • Bacterial intracellular proliferation within tonsillar epithelial cells occurs during infectious mononucleosis with membranous tonsillitis.
  • This bacterial invasion mechanism, induced by EBV and potentially exacerbated by streptococcal co-infection, may contribute to the pathogenesis of peritonsillar abscess.

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