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Separation of Immune Cell Subpopulations in Peripheral Blood Samples from Children with Infectious Mononucleosis
08:44

Separation of Immune Cell Subpopulations in Peripheral Blood Samples from Children with Infectious Mononucleosis

Published on: September 7, 2022

Causes for massive bacterial colonization on mucosal membranes during infectious mononucleosis: implications for

Lars-Eric Stenfors1, Helga-Marie Bye, Simo Räisänen

  • 1Department of Otolaryngology, Institute of Clinical Medicine, University of Tromsø, N-9037, Tromso, Norway. larseric@fagmed.uit.no

International Journal of Pediatric Otorhinolaryngology
|September 21, 2002
PubMed
Abstract

Insights

Infectious mononucleosis (IM) reduces protective immunoglobulin G (IgG) and S-IgA coating on bacteria, increasing colonization. Bacteria also penetrated epithelial cells, potentially worsening nasopharyngeal infections.

Area of Science:

  • Immunology
  • Microbiology
  • Otolaryngology

Background:

  • Virus-induced upper respiratory tract infections commonly lead to bacterial acute otitis media.
  • Increased nasopharyngeal bacterial colonization often accompanies these viral infections.

Purpose of the Study:

  • To investigate the causes of increased bacterial colonization during infectious mononucleosis (IM).
  • To evaluate bacterial coating with lysozyme, lactoferrin, and immunoglobulins (IgG, S-IgA, IgM).
  • To assess bacterial penetration into epithelial cells in IM patients.

Main Methods:

  • Collected oropharyngeal samples from 21 IM patients.
  • Utilized immunocytochemical assays with gold-labelled antiserum.
  • Employed transmission electron microscopy for bacterial and epithelial cell analysis.

Main Results:

  • Observed significantly reduced bacterial coating with IgG and S-IgA.
  • Noted a significant increase in bacterial coating with lactoferrin and IgM.
  • Found bacterial penetration into epithelial cells, especially in patients with beta-haemolytic streptococci.

Conclusions:

  • Reduced IgG and S-IgA coating on bacteria may contribute to increased colonization.
  • Bacterial penetration into epithelial cells could exacerbate oropharyngeal mucosal infections during IM.

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