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Definition of intracellular pathogens

Jeanne Orfila1

  • 1Laboratoire de Bactériologie---Immunologie Générale, Centre Hospitalier Régional d'Amiens, France.

Clinical Microbiology and Infection : the Official Publication of the European Society of Clinical Microbiology and Infectious Diseases
|March 1, 1996
PubMed

Insights

Host tissues typically destroy microorganisms via phagocytosis. However, this paper explores how certain pathogens, including viruses, bacteria, and protozoa, evade this process and replicate within macrophages.

Area of Science:

  • Immunology
  • Microbiology
  • Cell Biology

Background:

  • Host immune responses commonly eliminate invading microorganisms.
  • Phagocytosis and lysosomal disruption are key mechanisms of microbial destruction.
  • Some pathogens have evolved strategies to survive and replicate within host cells.

Purpose of the Study:

  • To describe the standard phagocytic process.
  • To elucidate mechanisms by which viruses, bacteria, and protozoa evade phagocytosis.
  • To detail the intracellular replication cycle of Chlamydia species.

Main Methods:

  • Review of established immunological and microbiological processes.
  • Analysis of pathogen survival strategies within macrophages.
  • Description of Chlamydia's intracellular replication cycle.

Main Results:

  • Macrophages engulf and destroy most microorganisms.
  • Certain viruses, bacteria, and protozoa evade macrophage-mediated destruction.
  • Chlamydia species exhibit a complex intracellular replication cycle within host cells.

Conclusions:

  • Pathogen evasion of host immune defenses is a critical factor in infectious disease.
  • Understanding intracellular replication mechanisms is vital for developing targeted therapies.
  • Chlamydia's survival highlights the diverse strategies employed by microbes to overcome host immunity.

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